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Listen here to some public service announcements featuring Lorne Greene, and some nice Rhodes playing.

You can take a look at the EIA code on  the power transformer to get a very general idea. I have 2 later 200A's with the Wurlitzer logo's on the back, one transformer stamped 9th week of '81, the other is stamped 29th week of '79.   Of course Wurlitzer probably used whatever stock they had lying around, so while it is not a very accurate way to date, at least you can determine that it was produced after a certain week/year. 

Also same idea with the EIA code the back of the Vib pot.   

http://www.triodeel.com/eiacode.htm

  I have a service note that we all might find helpful in keeping the 100 series alive. Here is the complete text:

E.P. Note No. 17                                                                                       August 17, 1964

                                    ELECTRONIC PIANO REED INTERCHANGABILITY

The left hand column below lists groups of E.P. reed numbers. The right hand column lists the E.P. models in which the reeds are interchangable.

               Reed Numbers                                            E.P. Models
       
                  1 thru 64                                           140A, 145A, 720A

                  1 thru 64                                           140, 145, 720

                  1 thru 64                                           120, 700

                  1 thru 64                                           110, 111, 112, 112A,

                  21 thru 64                                         120, 140, 145, 700, 720
                                                                         
                  52 thru 64                                         110, 111, 112, 112A
                                                                         120, 140, 145, 700,
                                                                         720

PLEASE NOTE that the model 140A, 145A, and 720A reeds are NOT interchangable with any other models.

PLEASE NOTE that the same reeds are used on the models 120 and 700 as on the models 140, 145, and 720 WITH THE EXCEPTION OF THE FIRST 20.

PLEASE NOTE that all models EXCEPT the 140A, 145A and 720A use the same reeds for number 52 thru 64.

With the following stock of E.P. reeds, every model Wurlitzer Electronic Piano can be serviced:

                                 Model 140A  - One complete set  (64)
                                 Model 112    - One complete set  (64)
                                 Model 120    - Numbers 1 thru 51
                                 Model 140    - Numbers 1 thru 20

  No mention of the 100, but I have seen an official picture of one. I currently own a 110 (which looks just like the 100 in said picture) and  a 111 (which is essentially a 112 in the darker finish, with the 110's amplifier)

Hope this helps!

[722728]

I know of a few members here with home pianos:
Polyvoks (Purchased from Harold Rhodes Jr.!)
tom z (seemed to have two at the time he posted)
myself
Speechless
hammondking

We also know of Ms. Carol Rhodes-Rice's: http://ep-forum.com/smf/index.php?topic=1038.msg14289#msg14289
And she mentions one that her brother Dave has in a later post: http://ep-forum.com/smf/index.php?topic=1038.msg14431#msg14431


I've previously posted my serial number 722728 and date stamps 4077/4473
And we got one from an ebay auction: 722879





If you'd all care to share your date stamps and serials, it would be interesting to see what we can learn.

Bjammerz has a good theory on the serial numbers, let's see if we can find corroborating detail:

Well the problem i've been seeing with serial numbers on the later stamp-era is that they don't completely correlate.  My guess is that the stamp was applied to the wood first, then coated, then sent out for pickup installation.

When they returned from installation of course was in no particular order.  So my guess would be that the serials are relatively close but could be a few hundred or more apart.  maybe not!

I expect Olivier's to be an "outlier" since we know more about the provenance, so I would not expect the serial number to be in sequence at all.

I'm also curious if we can determine that the serial numbers range on the harps includes any known suitcase or stage or other models.

Home piano owners, sound off!

[Apologies to basically everyone]

This one goes to eleven! Get your limited edition Mark XI vintage electric piano now!

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That's only the beginning: Each Mark XI is set up to our exacting specifications, then placed in a sealed "clean room" along with a Roland/Rhodes model 660, which is thoroughly destroyed at the molecular level in a painstaking proprietary process to remove negative vibe. ISO9001 certification on this process is pending ratification.

Mark XI is available in the two models: "classic!" and "super-classic!" Neither offers MIDI support, however the "super-classic!" has a custom, proprietary electronics package, created to actually obliterate all MIDI signals within 15 meters, creating a vintage "bubble" in which no keyboard technology invented after 1984 will operate. (Super-classic! model coming soon!)

Stevie Wonder's stage manager's amp tech's brother played a mockup of a prototype Mark XI and said:

Unbelievable tone! If Art Tatum, Leonardo DaVinci, and Bootsy Collins collaborated on an electric piano, it wouldn't sound half as good as this thing!

George Duke's barber looked at pre-production sketches of the Mark XI and said:

That right there is some FONK!

Jeff Lorber's attorney reviewed a Mark XI press kit we sent and said:

My client has no comment on this insanely awesome vintage gear that everyone should immediately order.

Robert Glasper's old roommate described the Mark XI:

Killin'. Just killin'.

Sergio Mendez's personal assistant answered a phone call from our factory while he was at the airport and said:

I'll probably order eight or ten of these!

Mark XI features:

• incrementally improved action
• 3 bold new colors
• platinum-plated RCA jack on the harp
• patented MIDI jamming capability (available on "Super-classic!" model only)
• color-matching accessories (sold separately)
• entirely new, revolutionary tine technology based on equipment we found in the basement of a Tibetan monastery
• Volume control that goes to XI
• Dual mono output (unbalanced)
• Each Mark XI precisely calibrated to fit in a 1967 VW Beetle (Beetle sold separately)

To pre-order your Mark XI, simply send us your non-refundable deposit ($650 discount if you provide your own sacrificial Model 660!), which will secure your place at or near the top of our waiting list. Mark XI pianos are individually handcrafted, and shipped in the order that they are built by our staff of expert technicians at our factory in an undisclosed location in the Sonoran desert. Shipping to Europe not available at this time. Supplies of vintage bomber parts are incredibly limited, place your order today! Now you can finally own tomorrow's classic built today from yesterday's classic!


















Apologies to basically everyone

Just some price data for the community.

I recently sold my 206A in excellent condition for $350, which was my asking price. It went within a day of listing it on Craigslist. Buyer didn't argue with me at all on price. The guy had a 207 with the display board, so he knew what he was getting.

http://www.youtube.com/watch?v=_JQMvidVo5Y
http://www.youtube.com/watch?v=zdCNGgUmg-I

These got taken down and are back for now, so watch em while you can.

I have been using a cheap Behringer mixer (MX802E) for a while just for convenience. I have two inputs at my sound card, so having the ability to leave all my keyboards and a mic or two hooked up permanently is a major workflow improvement.

What I had missed until recently was the EQ on each channel. when I was doing the phase shifter shootout I wanted the mixer to not color the tone, and prior to that I kind of ignored it. But when I was done I noticed an amazing detail:



The midrange control is actually a very close match for the treble on a suitcase pre in terms of frequency range affected. But on steroids when you consider the range and noise. The high at 12k in this case is really more of a presence thing (it makes damper kiss sound obnoxious if you crank it) so the mid knob really becomes treble for a Rhodes channel.

Now to me, 2.5kHz is pretty far north of midrange (hello, it's Eb7, the second highest note on a seventy-three), but what do I know, I'm just a piano player.

Anyways, I just realized that this cheap (I paid 40 bucks for mine used and got four mics and cords in the deal) box that I was considering a utility device is also a very valid effect processor. It also gives me an effects loop and level controls for the channel inserts so that I can use a phase shifter (or whatever effect) in a manner other than 100% wet. And manipulating the levels sent to the stomp boxes (or other processors) can affect the tone you get as a result.

So anyhow, keep an eye out for a cheapie mixer with a treble or midrange control that you can take advantage of. My opinion is that clean gain with wide-range modern EQ applied to a direct harp signal can whoop the pants off the signal you are getting off the preamp. I'll upload some samples shortly to back that opinion up. My latest recording is being done this way and I'm stoked about the results.

By the way, I'm aware that this is in no way equivalent to a proper mixing console channel strip. I'm not saying that, I'm saying it's superior to the 1970s peterson preamp design. You guys aren't going to find a Neve console at a garage sale, but you can probably grab one of these gizmos.

[today]

This thread made me think about this. We all know that the sacred scriptures say that the pickup wiring pattern was changed to groups of three from groups of six in the early part of the 70's, in order to get a hotter signal. So it is written.

But Jim's comment

in my experience it's less noisy in sixes.

really raises an important point, and a technology issue.

Namely: the decision of parallel threes made good sense in 1971 or whenever, under the effective limitations of technology at that time. But how about 2010? Don't we have access to preamps that beat the socks off the 1971 stuff? (hint: yes we do) Would it possibly make more sense today to go back to parallel six configuration?

Well, this should be measurable. Assuming my esteemed colleague from Oz is correct, we should be able to measure an improvement. And it can be pretty easily arranged in a reversible way with some croc clips and wire. I have a feeling he's right, but seeing the numbers is a must.

So I propose a Rhodesological experiment: temporarily reverse the wiring mod described in the service manual by means of croc clips and short wires, then measure the change in noise floor that results. Assuming there's a benefit, then proceed to investigate the other tone changes that come about.

But then the thought occurred to me, why does it need to be all sixes or all threes? If it's beneficial, why not bridge some of the gaps and leave others open, say to get a free bass boost or whatever tone-shaping effect you want?

[Test setup:]

The old phaser thread was one of the top viewed pages on the forum (#10 as I write this). And it doesn't even have any info for the guy who wants to make a direct comparison. So wouldn't it be cool to have a proper shootout? Oh yeah.

Today we'll be squaring off the modified MXR Phase 90 (my assumption is you'd not want to use the unmodded one at all, it sounds poor) versus the unmodded EHX Small Stone nano edition. I have not modded or even considered modding the EHX because out of the box it comes as true bypass, and it uses all surface-mount construction to frustrate the budding modders out there.



Both pedals are of similar size and basic construction--the nano series EHX pedals use a "bud box" housing like the MXR pedals, although it's not as heavy, and not painted. Both are "one-knob" control designs, with only a rate knob and bypass, but the EHX has a "color" switch to give you two different depth settings.

I am using the down position of the color switch throughout. The up position is not a setting I consider useful other than for special effects.

Test setup:
To make the shootout as fair as I could, I ran my piano's direct-from-harp signal into the phaser input, then the phaser output into my mixer using a channel set up for no EQ, and just enough gain using the channel input trim to get reasonable levels for recording (I get a great signal-to-noise ratio this way as well). I'm going to present a lot of measurements in this post and hopefully the setup description will help you understand how I got them and why they are interesting. I use Reaper as my digital audio workstation (DAW), and several of its included tools were handy in making various measurements.

Noise:
Neither device will be a noise-free unit. I measured my noise floor with no phaser (no signal coming from Rhodes, measured signal level at the DAW channel) at -69.6dB for my test setup signal chain as described above. That number accounts for everything in the path, the mixer, patch cords, all of it. I normally experience about -59dB when I record off the preamp into my typical chain for what that's worth. So this is a quieter setup.

I measured the noise floor as above with the effect switched on and with it off for both units:

	on	off
EHX	-67.5dB	-69.6dB
MXR	-68.1dB	-69.5dB

Switching noise:
Both units generate a significant noise when they are switched in or out. It varies, but the spikes are in the neighborhood of -51dB for MXR, and -35 to -48 dB for the EHX, which varied considerably more. Both are going to be audible in a recording, or cause audible clicking though your stage rig. Probably limited to annoyance level either way, not eardrum-breaking.

Level drop:
I pressed my Kaossilator into service as a quick and dirty test tone generator. I sent a constant amplitude tone into each phaser, then measured the level drop for switching the phaser in. Here's the first real differentiator between the units: the EHX is designed specifically not to drop your levels when it's on (this is particular to the nano version from what I've read online).

EHX level dropped by 0.2 dB switching in the effect, while MXR level dropped by 4.9dB, a noticeable amount. Measurements were made RMS with a 300ms window.

Tone:
Here I'll let the recordings tell the story. You are gonna like what you like. There's no overwhelming technical advantage to either unit, so go with the sound you dig. All are either 100% wet or 100% dry. No other FX or even EQ are used.

In this test you hear the dry sound then the phaser switched in.
MXR: http://shup.com/Shup/434901/phaser-shootout1.mp3
EHX: http://shup.com/Shup/434902/phaser-shootout2.mp3

These are with the phaser on throughout, but I level matched the two clips (raised the MXR clip 4.9 dB to compensate)
MXR: http://shup.com/Shup/434911/phaser-shootout3.mp3
EHX: http://shup.com/Shup/434912/phaser-shootout4.mp3

Again level matched:
MXR: http://shup.com/Shup/434920/phaser-shootout5.mp3
EHX: http://shup.com/Shup/434921/phaser-shootout6.mp3

Again level matched:
MXR: http://shup.com/Shup/434928/phaser-shootout7.mp3
EHX: http://shup.com/Shup/434929/phaser-shootout8.mp3
Here's why I don't use the up color position:
http://shup.com/Shup/434930/phaser-shootout8A.mp3

Here's a sweep of the rate knob from bottom to top on both. I think the knob on the EHX has unusable settings at both extremes. MXR knob is unusable at the low end, with useful settings starting at around 10 o'clock. both start to sound interesting at around 12 o'clock.
MXR: http://shup.com/Shup/434935/phaser-shootout9.mp3
EHX: http://shup.com/Shup/434936/phaser-shootout10.mp3

And from the pure self-indulgence perspective, it is interesting that how the thing sounds affects your conception of tone and articulation and you adjust to the thing. Here's a couple clips where I just played in a short loop on the Kaossilator and played along. You can kind of hear how the tone thing affects what I do, or maybe not, who knows. These are just a bit longer clips, still just about 2-3 MB though. Reverb and EQ helps these clips out some.
MXR: http://shup.com/Shup/434940/phaser-shootout11.mp3
EHX: http://shup.com/Shup/434941/phaser-shootout12.mp3

Just a data point:
on my local craigslist there's a nice looking suitcase 73. It was first listed for 875USD two weeks ago, then it's currently been listed at 800 for about a week. It has not yet sold at that price.

I think a couple years back it would not have lasted long at 800.

[Rhodes buyers guide]

Rhodes buyers guide

Background: "Is this Rhodes worth the asking price?" "How much should I offer the guy?" If you've asked these questions, this guide is intended to help you through the buying process. A few basic assumptions apply to the use of this guide:
•   You are considering buying a Rhodes Mark I or Mark II. Other models are more specialized and possibly of interest mainly to collectors, so if you are after a sparkle top or a Mark V, student, home or other specialty model, the guide is going to assume you already have a decent reason to go after one of those models instead of the mainstream Mark I and Mark II.
•   You will get the chance before purchasing to inspect the piano in person, and "test-drive" it. Obviously that won't be true if it's an ebay purchase.
The two basic models you will run into are Stage and Suitcase. The main difference is the Suitcase includes an amplifier and active preamp, while the Stage is a passive piano requiring external amplification. Both were offered in 73- and 88-key flavors, and a 54 key stage Mark II also briefly available.

The Rhodes pianos we're discussing here were produced between 1970 and 1981 for the most part. The Mark II designation was introduced around 1980. So in reality, there are more differences among Mark I pianos than between a late Mark I and a Mark II. Here's the basic "eras" of Rhodes production, as best we understand them, simplified somewhat for our purposes here:
•   Early Mark I pianos (1970-1974) are considered desirable by some people due to differences in the tines. Be aware you may not get all original tines. Early pianos have none of the action improvements that later pianos got, so pay extra attention to how the piano feels. Early pianos were subject to problems with dampers and double striking hammers. The key pedestals have felt on them. Hammers are a plastic/wood hybrid. The easiest way to spot a piano in this era is the inclusion of the word "Fender" in the logo badges.
•   Middle Mark I pianos (1975-1977) came about as a result of a change to the action. The hammers became all plastic. The pedestals became bare wood and the felt was placed on the hammers.
•   Late Mark I pianos (1977-1979) the next step in evolution was a bump placed on the key pedestal, in conjunction with the return of felt to the key pedestal. Late Mark I suitcase pianos also featured a new, more powerful amp design, easily spotted by the five pin cable used to connect the suitcase bottom.
•   Mark II pianos (1980-1981) came in two varieties: wooden key models and plastic key models. Plastic was used later to avoid problems with wood parts warping, and to reduce weight. The pins holding the plastic keys are difficult to repair if they break, and somewhat more subject to breakage than the metal pins in all the older designs. For that reason, some consider a plastic key Mark II to be less desirable. Other than the obvious "Mark II" labeling, a Mark II will have a flat top instead of the curved top on a Mark I.
The date stamps found on the harp will help if you have trouble determining which bucket your piano falls into. Look for a stamped, four digit number in the upper right corner of the harp. The last two digits are the year that manufacture started. Consult the EP forum for more detailed info on dating.

Checking out the condition
There is very little that can go wrong with a Rhodes that can't be repaired—at a cost. So when you check out your prospective new piano, look for the things that will be costly to replace or repair, and use those things as negotiating points with the seller. Especially if the seller represents the piano as in playing condition, pointing out the repairs needed can help you get a better price. Plus you can avoid buying a piano that will ultimately only be good for parts.
1.   Check all the keys for correct travel, stuck notes, stiffness or other problems.
2.   Look for broken tines. These can be replaced at a cost of around 25 USD per tine.
3.   Check that the dampers correctly stop each note from ringing and note any problems. Replacement damper felts are readily available and simple to install.
4.   Note any missing hammer tips. Replacement tips are usually sold in complete sets.
5.   Look for stiff or cracked grommets on the tonebar assemblies. Grommets are a fairly simple refurbishment to do, but time consuming.
6.   For suitcase pianos, check for the preamp cord and make sure it works. Newer pianos had a five-pin cable, older ones a four-pin.  Replacements are available for both, but will cost in excess of 60 USD typically.
7.   Examine the electronics package. Note any aftermarket modifications made. Many mods don't hold up well at all and will need replacing or restoration. Factory original tone controls and preamps held up well generally, but preamp rebuild kits are available if you need one. The amplifiers in older (4-pin) suitcase models use transistors that are expensive to replace.
8.   Check the operation of the sustain pedal and damper release bar. The pedal rod presses up on a wooden dowel which moves the damper release bar, allowing all tines to ring freely. There are pivot points at both ends of the damper release bar; inspect these for free travel and to make sure they are seated in the holes in the harp support blocks.
9.   Turn all pots and check for noise and static. Pots can be cleaned but may need to be replaced. Original replacement knobs for older styles are nearly impossible to obtain, notably the concentric-knob preamp.
10.   Stage pianos should have a set of four legs, two braces and a knob in order to be considered complete. There was a vinyl bag for the legs, but it is not used other than for storage. The knob is a standard 1/4-20 thread, so don't get tempted to buy a spendy replacement off ebay; just hit the hardware store.
11.   Suitcase pianos have an amplifier as their base. Check that this powers on; if not take a look at the circuit breaker or fuse. Power cords are easily replaced. The older ones use a standard extension cord; newer ones use a cord with a standard IEC connector like a computer or monitor uses.
12.   Check the pickup wiring for breaks in continuity. There is a repeating pattern of connections, and some breaks in the wiring are normal and expected. Check the manual for some diagrams of how this should look. Any dead notes may be caused by failed pickups. Test a pickup by lightly tapping with a metal screwdriver. No noise means dead pickup (or break in the wiring).
13.   Remove the four screws that hold the harp down (two on each end). Raise the harp and look at the hammers, checking for broken or missing hammers. Lift the hammers up and look at the key pedestals. Note any missing felts or other problems. These are usually easy things to correct.

The right Rhodes
If you find a piano that you enjoy playing, you should buy it. You can make a significant difference to the way it sounds by means of adjustments later. The thing that's' harder (but still possible) to correct after you buy it is the feel. Most Rhodes pianos are not in a well-adjusted condition at this point in their lives. Some never were. But with some attention and patience, you can set up most any Rhodes to sound quite good. Some problems that are really hard to correct, and may be better left to the professionals/collectors/techs:
•   Double strike problems that seem to be more common on the early action design.
•   Warped keys or warped keybed
•   Water damage
By no means is this a complete list of serious problems. But stay away from anything like these unless you are confident in your ability to do a restoration (in which case you probably don't really need this guide).

The Rhodes market
At the time that velocity-sensitive keyboards like the DX7 first became popular, Rhodes pianos were considered to have very low value. And it was all down to weight, with just a little help from the idea of having the latest sound available. But given the choice between taking a 100-pound plus Rhodes to the gig or a 30-pound DX7, most people went the light direction. So there was a time when Rhodes pianos were almost free.
Those days are clearly gone. The last few years have seen a resurgence of popularity as people gained a new appreciation for the unique sound of a classic Rhodes piano. And prices had been steadily on the rise for all kinds of retro gear, no less the Rhodes. But the great thing is that this was an instrument that was manufactured and sold in large numbers over a period longer than a decade. Many schools bought them. So they are in no way rare, other than the models at the top that I specifically said weren't covered by this guide.
Your location will influence the selling price greatly, mostly due to the supply of pianos compared to the demand. Outside the US, prices are markedly higher. Inside the US market, pianos will bring more in larger metropolitan areas than in smaller cities. So if you post in the forums asking if you are getting a good deal, it helps a lot to know where you are, because a great bargain in Denmark may be a premium price in Des Moines.
In the US market, almost any Rhodes will bring a minimum price of 350-400 USD regardless of condition, just due to its parts value. There's a lot of fluctuation in what people are willing to pay for a Rhodes in excellent or mint condition. Not as many pianos survive in that condition, so it's harder to be definite with the price, but an excellent condition suitcase could bring 1200 USD almost anywhere, and an excellent stage 1000 USD. Few Rhodes pianos are truly mint.
Generally speaking, refurbishment does not detract from the value of a Rhodes piano. Many parts were designed to be field-replaceable, so repairs and refurbishments are more the rule than the exception. Mods can add somewhat to the value of a piano, but only if done well and in operating condition. A lot of mods are poorly-executed or poorly thought out, and can detract from the value, since you'll potentially have to spend additional money to restore a function of your piano. Sticking with stock is a safer bet for the first time buyer.

[Prep:]

This has come up from time to time as a question, what's the best product and technique for painting a Wurli top?

I've consistently recommended using Vinyl Dye, so today I am prepared to put my proverbial money where my mouth is and show you why.

The Wurli manual specifies that the top is made of ABS plastic, and I have had excellent results using vinyl dyes on ABS. Vinyl dyes are sold in your auto painting store, including in some places like Wal-Mart, so this is not hard stuff to obtain at all. You should look for a rattlecan with the word "Vinyl" in the product name. Plastikote and Dupli-color both make an excellent product that I've used in many projects with great success. There are many other brands too.

Prep:
The best part of using Vinyl Dye is that lack of the need to sand your workpiece. It's great because you'll retain the original texture of the piece, and do less work along the way. Just clean all dirt and grease off, I like to use isopropanol for this. Due to the texture, using a brush is good to get the lower parts clean.  I taped off the metal trim and hinges. In my case, the metal name badge removed itself, but for most cases I'd recommend you mask that too--removing the old adhesive was no fun at all.


Product:
I am using Dupli-color Vinyl and Fabric Color. Your can may not look exactly like this one I had around (it's old, but still good).You put it on like spray paint, but unlike regular paint, it is very thin, dries quickly, and won't build up or cover the texture of the workpiece.


Technique:
You want to stay well back from the workpiece, at least 12 inches, and spray a lot of very light coats. It's hard to get the sense of what I mean by a light coat, but if you look at the cardboard beneath, that should let you see that I'm talking about very sparse application. It's really easy to get a great result with these products.

Spray outside only--the fumes from this stuff are noxious.

Okay, enough blab, let's look at the results. Here's the before and after view:


and a couple more showoff shots:



and just a couple more:


I'm not saying this is the only way to go, but I think the results above are fairly compelling. One can of this stuff would do several piano tops. I spent less than five bucks and about one hour to get the results shown.


Edit: updated product link
Edit: flickr is dead to me--moved pix to dropbox and super-sized

I could use a bit of coaching on this one from my fellow forum members. I want to remove the action from my 200 (not A) in order to lube the action centers. I have all the classic sluggishness that makes this maintenance a necessity. There's a great video up on youtube on doing the actual procedure, but it quickly blows past the removal from the case.

I've gone as far as pulling the amp rail out, but in my piano the power cable socket in the back corner is hardwired to the amp assembly, so I don't see how that's gonna come out as a unit. (I could put in a connector, but I'm in all original condition at the moment, so I'm mildly hesitant, although I note the ground pin is absent from my power cable).

I'm thinking there's a solution here that avoids removing the amp rail at all, but I still need to figure out the power cable. It's zip tied to the harp supports and there's very little slack to work with. As a last resort I can unsolder the power leads from the socket.

And while I have your attention, any thoughts on alternative lubricants versus the silicone thinned with naphtha that is recommended in the manual? I have some Teflon suspension that I could use, but I'd have to buy the silicone (I have naphtha in my shop).

[Concise version]

The cheerful little orange box. I used to have one back in the late 70's, long since gone.

I'm posting cause I bought one today for a little bit of nothing. If you poke around the web at all, you'll find plans for modifying the more recent versions of this to improve a certain degree of midrange clipping/harshness/distortion in the modern version of the design. You can also choose to pay big bucks for a vintage "script logo" version (before Dunlop took over and screwed it up I guess), or a current one that is a reissue attempting to recreate the old school vibe.

For me, cheapness is a serious virtue, so I grabbed up a vanilla recent version of this pedal used and set out to carry out the "R23 mod." I also recorded a bit of before, during, and after for your listening enjoyment.

With the stock circuit, I agree that this pedal basically is unusable. The harshness you get in the upper mids is truly nasty. Here's an audio clip that kind of shows it at its worst disadvantage:
http://shup.com/Shup/374771/phase-90-1.mp3

So the first step is to remove the feedback resistor R23. This second clip represents the sound after that change:
http://shup.com/Shup/374773/phase-90-2.mp3

The second step is to remove the two capacitors C11 and C12. this is optional, but it can improve the tone further. I decided that I couldn't stand the thing distorting so badly, so out they came. Here's the improvement:
http://shup.com/Shup/374782/phase-90-3.mp3

And a short musical selection using the fully modded Phase 90:
http://shup.com/Shup/374785/phase-90-4.mp3

I think it's a vastly improved sound. As good as the vintage pedal? I can't really say. I have used exclusively software phase shifters for recording since I got my suitcase, but this pedal modded is likely to find a semi-permanent place in my rig.

Drawbacks:
- There's no wet/dry control on this pedal, so you have to either put it in an FX return to get that mix control, or live with the lack of it. There's a trim pot inside that you can tweak the wet/dry mix with, but that's not really satisfactory. Mine's in the loop on my mixer, and it really livens it up to mix in a bit of dry sound with the phased sound.
- No feedback control either. Deal with it.
- It's mono. Maybe that doesn't bum you out, but I like the stereo phaser sound.
- Recently made ones use surface-mount components, making  then slightly harder to mod. Mine was through-hole and dead easy to modify with nothing more than wire cutters.

Upside:
+ There are ten zillion of these out there, so you can almost definitely find one cheap.
+ The frequency response is such that it actually improves my noise floor slightly, believe it or not. The 120Hz power supply buzz gets damped pretty well by mine (not eliminated or anything).
+ Cheap!
+ Easy to mod.
+ Cheap!

So if you have a Phase 90, and you think it sucks, go here to find out how to do the R23 mod:
http://www.erikhansen.net/pedal-mods/mxr-phase-90-mods
Concise version: clip out the three marked components in this pic:
http://www.erikhansen.net/diy/phase90scriptmod.jpg
You'll get a much more usable pedal.

If you don't have one, go get one. Phase 90 + Rhodes go together like hot fudge and vanilla ice cream. Don't get suckered in on the upmarket ones (like the 74 handwire or the EVH version), buy the low end one and get after it yourself.

Is the bestest phaser ever? Nope. Too few knobs to even be in the running. But it's a nice addition to the signal chain.

Too many pill spammers eh?

This is one I haven't seen much discussion on around here. Back in the 70's I played a Rhodes in a music store where the guy had modded this pedal into the namerail (very cool) along with the phase 90. I tend to associate this pretty strongly with the 70s.

Today I just happened to buy one of these little gems (vintage, naturally) off CL.

This is a simple auto-wah effect (sometimes called triggered wah or t-wah), with a filter that has all its parameters fixed other than the center frequency, which moves in response to the amplitude of the input signal. There are threshold and attack knobs that govern what level will trigger the wah, and how fast it sweeps, respectively. So it does what a wah pedal does, but with no need to rock your foot back and forth.

The threshold knob allows you to dial in a setting that gives you some control of the effect (in that it will trigger when you play harder). I have mine connected in the fx loop of my suitcase, and the level is enough to trigger it effectively at my normal playing volumes with the threshold control at 12:00.



audio samples to follow shortly...

I saw Stevie Wonder last night and I thought you guys may be interested in the equipment he used.

Stevie had a back line with two percussionists, two guitars, two keyboardists, drummer and bass, sax, trumpet, plus four backup vocalists.

Stevie's rig was a Yamaha C7 grand, which he played about 50% of the time, a Motif XS8 that he played about 35% of the time, and a D6 clavinet that was modded with an FX loop and a balanced out, which he only played a little (Superstition, Higher Ground). There was an electric drum kit set up in front, but no one played it.

First Backup keyboardist had a Motif XS8 and a Fantom of some type. Second one had a Motif XS8 plus a D6 clav. I couldn't see any rack equipment on anyone's setup, but that doesn't mean there wasn't any (I kind of doubt it though from what I heard).

The notable thing for us: no Rhodes piano (new or old) in sight anywhere. They played a faux Rhodes sound on the Motifs about 80% of the time, sometimes with some over-the-top effects, sometimes using the pitch bender quite a bit (not Stevie with the pitch bend).

He did quite a bit of his show for Michael Jackson, played several of his tunes, and did a pretty amazing talkbox "sermon" playing the Motif through the talkbox as kind of an extended solo where he talked about Michael. He only played harmonica a very little, but he did on Chick Corea's "Spain," in which everyone in the band got to take two choruses.

I couldn't get a really good detailed pic of the stage due to security, sorry. Here's a crappy one:

Not my ad:

http://kansascity.craigslist.org/msg/1184246302.html

Wurlitzer 1956 Electric Piano Model 112 - $850 (Lincoln, NE)
Reply to:sale-tr86m-1184246302@craigslist.org [Errors when replying to ads?]
Date: 2009-05-22, 4:38PM CDT


Complete right down to the lid, music rack, pedal and bench, as well as the original manual. The TUBE amp (later models like the 200 were unfortunately solid state) is in perfect working order, original speaker is in great shape, and this thing breaks up just like you want a Wurli to when you turn up the volume. The action is decent; completely playable as is.

1956 Wurlitzer 112 electronic piano, the very first model made by Wurlitzer, and exactly the sort used by Ray Charles on his hit song "What'd I Say." This machine is all original in funky mottled beige/brown paint, and its overall condition, considering the fact that it's 53 years old and portable, is pretty close to mint. A bit of paint is worn off around the edges, but it's a very pretty instrument. I've had it about seven years, and bought it from the original owner; it's been well taken care of.

Now on to the couple of issues it has...as you can see in the second picture, the gold beauty ring around the top of one of the bench legs is missing. The rings aren't glued on, and so it unfortunately disappeared sometime in the past five decades. The other problem is that the reeds on keys #25 and #30 are broken. It is unavoidable to break reeds on these things unless you play incredibly gently...kind of a paradox, as playing a little bit hard is a big part of where you get the magical Wurlitzer tone. At any rate, reeds can be ordered at a couple different places online such as vintagevibe dot com. If you're at all mechanically inclined, this is a tedious-yet-doable proposition...I have replaced about three reeds over the years, but just haven't had time to replace the two that are out right now. A person would be smart to keep spare reeds for the middle keys, and maybe purchase vintagevibe's kit for molding the lead tuning weights onto reed blanks. By the way, this comes with a couple spare reeds (unfortunately not the ones that need replaced).

Be forewarned: you must come pick this up...I am not willing to crate it up and let it receive a bunch of damage in transit.

Included: The piano; The bench and music rack; The lid; The sustain pedal; The original owner's manual; Power cord; spare reeds.

A superb Wurlitzer at a price far below online vintage shops. Add this sweet antique to your collection.

http://www.youtube.com/watch?v=SqtTmUZDoKM

He hits a quick riff at about 4:16 on a nice sounding mark I stage. What's this guys's name?

This is a complete rundown on the Home Piano I bought last summer. Say hello:



Pretty much this is a mid-seventies seventy-three piano in a walnut veneer case, with a mono amp and a couple other odd features that we'll see up close shortly. Inside the case what you find is a regular Rhodes action that you could drop into a suitcase case and play.



The tone controls are neither the standard suitcase nor stage setup. This is a completely different electronics package. The piano is actively amplified, and has a mono active preamp that's different to the suitcase design.



Take a look at that namerail profile--this is the Mark II extrusion, but it's powdercoated in a chocolate brown color. This piano was made in 1977, so this may be a hint about the origin of the Mark II namerail profile. Anyone have one they can date earlier than 1977?




Very clearly readable datestamps, showing dates consistent with the action features we'll see later.




Same tone mechanism as any Rhodes of the era.



One of the unanswered question: what's that left pedal do? Now we know: it is a swell pedal, essentially a volume pot in parallel with the main volume pot on the namerail, controlled by the pedal. However you have the namerail volume set, including full off, this pedal makes that louder when you press it. As far as I can tell, this is a completely useless feature. We'll see some pics of the guts in the base that make it work later on.



Also unique to this model as far as I know: a headphone jack and power switch in the left cheek block. So my statement above about dropping it in to a suitcase is a little bit misleading.



You can see the side profile of the case here, it's the same as earlier design student models. It's a particle board case with a fairly thick walnut veneer on it, and it's stupidly heavy. My flash makes the nicks in the veneer here look a lot worse than they do in real life.



Back of the cabinet will remind you a lot of the student models. Same interesting brown grill cloth at least. Notice that the bottom  rail in his cabinet is not veneered--it's pine with a stain attempting to match the rest of the cabinet.



Closeup on the amp panel--you can't quite read it here but it says 200 Watts on the nameplate, and it is insanely loud, far too loud for indoor use at top volume. Standard fuse holder in case you need to change it out, but no line out connections at all, sad to say.



Unique construction to this model on the top of the cabinet: the lid is hinged at the back with a piano hinge (appropriately) and has a support on one side that locks it upright much like a blanket chest would have. Also note the small stop screwed to the inside to support the lid when it's shut. There's tiny felt buttons on the top edge to cushion the lid.



Filling hte gap above the namerail and below the front edge of the lid there's a veneered panel that is removable. It's held in place on each end by these latches, which you only see with the lid raised.



Here's another shot of the piano hinge on the lid (don't say I'm stingy with the pictures...)



The corners of the namerail extrusion are rounded, but the cut is concave rather than convex like you sometimes see on later Mark IIs. Possibly unique to this model.



The holes in the back panel are filled with a sort of plastic bushing, that has unfortunately not withstood the rigors of time. These are both disintegrating. But after unscrewing the back panel, you pull here to remove it from the case. There are no speakers in the back panel, which seems perfectly sensible for a piano intended for home use. But also there's no access from the front.



With the back panel removed, we see the single 12" speaker.



The power supply unit is housed in an enclosure with an open top. Not a particularly good choice in my opinion. Perhaps mine is just missing the cover, but I looked for evidence of that and I do not think that's the case. Eagle eyed readers will note one of my PSU caps has been replaced, that was done by the guy I bought this from, who is a tech. Notice the additional fuse only accessible from within. This PSU is also supplying power to the tape deck that's built-in, which we'll see later.



The amplifier is fully enclosed in metal, for reasons that ought to be obvious. Note there's yet another fuse, or at least a holder. Safety first!

While we're here, note the sustain pedal mechanism, which is the same as a suitcase. The upright is a chunk of wood with a bolt threaded in to the top.



This wiring harness is for the tape deck. This makes it easy (or at least possible) to remove the deck for separate service. Mine has the tape deck, and it works. Playback is through the cabinet or headphones.



this is a genuine mystery: this shot shows the underside of the top of the speaker cabinet. I am looking upward in this shot. Why does this have a hole? Why is there a grill cloth over the hole?

My theory is that they used leftover stuff from other amp cabinets where they could for cost savings. Maybe this was destined to be a front panel but the shop manager wasn't happy enough with it for some reason (cutout is the right size for a speaker, but kind of dodgy looking) and had the cabinet guy use it as the top instead. Who knows?



Another power supply shot. All the wiring to the various units is modular, with connectors making it removable for service.

to be continued......

http://youtube.com/watch?v=yCJY6AEGL2s

Unbelievable

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=320335882931

http://www.youtube.com/watch?v=PaIfbt7gYCk&fmt=18

Much better audio quality than other similar videos. He demos a Mark II through a few different amp setups: Fender ProReverb, Roland JazzChorus, TRamp.

Worth watching, very well done.

Yesterday a 206A added itself to my studio.

This is the nicest Wurli I've ever come across. The action is fantastic. It's very clean on the outside, just short of mint condition. It's been modified to take AC power, and the mod is super crude, just a lamp cord electrical taped into the internal wiring.

Sustain pedal needs to be fixed, i haven't opened it up yet to see what it needs. all notes sound except one dull one near the top.

It is badged "Musitronic" instead of Wurlitzer.  Pics to follow shortly.

Master

Model FR7220
Serial 344-060
Logo old Fender Rhodes

Having just changed a tine under duress, here's my thoughts on what would be needed to effectively service your piano when caught away from the shop.

Minimal:

• #1 phillips screwdriver (for removing/replacing the harp screws)
  
• ratchet with 5/16" socket (for r/r tine mounting screws)
  
• lineman's pliers (for trimming tine to length)
  
• 3/8" open-end wrench (for gripping the tine mounting block when replacing)
  
• 1 or 2 extra tines with tuning springs
  
• extra tine mounting screw (in case you drop one and it gets away)
  

Nice to have:

• little flashlight
  
• retractable magnetic grabber (for getting broken tine ends out of the key bed)
  
• #2 philips screwdriver
  
• unopened tube super glue (no way would I carry it opened)
  
• extra hammer tips
  
• extra damper felts
  

Anyone else want to add on to the kit?

Not my auction. Kind of a shame someone is parting out a Mark V, but you dudes need to know about it.

http://shop.ebay.com/merchant/starkontology

http://www.youtube.com/watch?v=UVfOMy_vBbI (1 of 4)
http://www.youtube.com/watch?v=6BGn7olcJQo (2 of 4)
http://www.youtube.com/watch?v=dfh36yldmvY (3 of 4)
http://www.youtube.com/watch?v=1EHsZdPkU8c (4 of 4)


Zawinul's going topless--seems to be the done thing in that era. About 5:30 of part 2 is when the piano soloing starts in for real, but only lasts less than a minute. It's kind of interesting that the video editor found shots of the guy whacking shoes together so much more visually compelling than Zawinul playing piano. At 6:50 of part 3 you get a little longer Rhodes solo.

The mystery box on top of the Rhodes seems to say OBERHEIM across the top, and it's pretty clearly patched into the effects loop of the suitcase, but I have no idea what it could be (sounds like overdrive). Wikithingama seems to think Oberheim the company was founded in 73, which would be 2 years after this session if the date is accurate. Since it's a broadcast, I expect the date to be pretty accurate. Wiki, not so much. :roll:

These two tunes are both on Zawinul's 1971 solo album. Interestingly, Wayne didn't play on that, it was Earl Turbinton. So I guess this is proper Weather Report.

A friend of mine is looking for this, anyone here have an online source?

A whole mess of good video tech tips:
http://www.youtube.com/profile_videos?user=vintagevibekeyboards

What the HELL are you feeding that cat?

http://www.youtube.com/watch?v=ZbjDCZFdEk8

http://www.youtube.com/watch?v=I5-ORooCaTI

Is it just me or is this guy's tremolo not even?

http://kansascity.craigslist.org/msg/770024582.html

I'd never heard of it until I saw this CL listing.

Links to get the pics cached here:

There's a local CP-70B up for sale, although the seller doesn't describe it as such (this is good). Edit: they've got it described correctly now.

What are current opinions of value on these beasts? I haven't gone to see it myself but it looks to be in very good condition.

I really don't want it but I may be able to steal it.

http://www.youtube.com/watch?v=sX2eyX4iSfA

Two Rhodes players in this one. Adam Holzman and Robert Irving.

[on topic]

http://www.youtube.com/watch?v=838NRZ1m8wU

I'm not really all that sure how useful this is, but it's on topic!

Executive Summary: if it hums, change the power supply caps.(bonus tip: don't lose your screws)

[not]

Compression in this context does not mean taking an audio file and making it less obnoxiously large while simultaneously degrading the sound. Compression in this case means using a device (hardware or software) to manipulate signal gain in order to effect the dynamics envelope of a sound.

Think about the Rhodes tone as having two separate components--an attack transient and a decay component. Compression will allow you to determine the balance between these, which in turn can allow "sculpting" your tone into anything you may want it to be.

A compressor is a difficult effect to describe--it can wear many hats. There are no presets, because its effects are heavily dependent on the program material (the signal you're messing around with). To keep things easy, I have recorded a single note in mono that will be our test signal. If you read any of my "dimensions of tone" articles, you will remember that the Rhodes decay profile resembles an exponential decay over time in terms of its general shape. This is precisely what you'd expect out of a physical tone generation system.

I then proceeded to run that test signal through a software compressor, with various settings. I'll present a few visualizations of the resultant waveforms, and then we can have a meaningful discussion about what this tool can do to your tone.

MP3 of the test signal and the processed versions can be played or downloaded here:
http://www.divshare.com/download/4185952-665

Here's an Audacity screenshot showing all the results with linear amplitude scaling. All the graphs below are 8 second sections from this:
http://stashbox.org/99717/10836134047-My-Desktop.png

And another with log (dB) amplitude scaling:
http://stashbox.org/99713/1083613360-My-Desktop.png


Results and discussion


Signal in the top lane is "clean" which is the single test note recorded direct in mono, no effects. Note the nearly exponential decay envelope, which in log scaling looks like a straight line.



So in the first processing example (second lane), I set out to "warm up" my tone or give it more "body" by slowing down the decay.  I chose a mild amount of compression, with a ratio of 3:1 above a threshold of -15dB. Makeup gain is turned on. So two things occur: The parts of the signal above -15dB (you can see from the Audacity screenshot that is around the first 3 seconds of the tone) are lowered in gain according to the 3:1 ratio, and then the makeup gain setting raises the level back up so that the peak level is the same as it was before the reduction. This makes the first three seconds of the tone "fatter" or fuller, or just plain louder really. It's a perceptible amount of effect when applied to music, but it's not real extreme. You won't hear a lot of difference playing the mildly compressed single note next to the clean test signal.

Note that none of the settings are absolutes. -15dB just happens to be 3 seconds in on this waveform, but when playing music it may be 1 second or 15 milliseconds or whatever. So as noted, there are no presets or cookbook recipes.



The second example (third lane) applies the exact same concept, but takes the amount of compression further. The ratio is set to 10:1. Now you can definitely see the point in the decay envelope at 3 seconds where the original signal crosses below the -15dB threshold and the compressor quits working.



The third example (fourth lane) uses an even more extreme compression ratio at 50:1, but I turned off the makeup gain. It's like someone slamming the fader down very quickly on a mixer. How fast the slam happens is governed by an attack setting on most compressors. Fiddling with this setting is how you determine whether the compressor operates on the attack or decay portion of your tone or both. In this example, the compressor slams down hard so fast that you just get a tick of the transient attack.



The fourth example (fifth lane) is an example of limiting. It's like hard compression taken even farther. In hardware, there are specialized devices for limiting applications, and there are software limiters as well. But a compressor  with a high ratio and a fast attack is generally said to be in a limiter configuration. Like this example. This gets done by mastering engineers to entire mixes to raise the apparent loudness of a mix by making the average level (which is what we perceive as loudness) higher in relation to the peak level.



The fifth example (bottom lane) is a transient shaping setup. I decided that I wanted to emphasize the attack, so I set up a 25 ms attack time and a high compression ratio (20:1). now the guy slamming that fader down has to wait until after we are done with the attack portion of the tone before he can do what he did in the third example above. And the slamdown is less extreme. But now you start to see how you can literally design your own tone quality with this equipment.

These are actually simple examples of the application of compression. The things are so flexible it's unbelievable. In a studio, you can send a signal to a compressor and mix the compressed and uncompressed versions down to get a new thing. you can trigger the compressor from some signal other than the signal fed to its input.  You can arrange compressors in series to do different things (like knock down transients with one, then raise the average level with the next one). You can divide the signal up into distinct frequency bands and manipulate each separately with its own compressor (multiband compression)

What happens when you apply these things to music depends a lot on the nature of the program material. You can't really "cookbook" compressor settings. you can set p a ratio that is intended to accomplish the result you want, but then you need to lower the threshold until you hear the amount of the effect being "correct" to your ear. The settings all interact, so it can be difficult to get started using these tools. However, once you open the door to manipulating dynamics, you won't want to go back. And if you want to know how your favorite player got some magic sound on that album: this is certainly how.


References:
http://en.wikipedia.org/wiki/Dynamic_range_compression

Anyone have the part number handy? I have the concentric knob preamp, and I can't determine from the drawing on the site what the part number is. I'm making an electronics order and I want to get some to have on hand.

Edit: I know the ORP61 number is on the drawing, but is there a modern meaningful cross reference?

Edit2: sorry, ORP61 is the LDR, I still need the bulb reference please.

Christopher Ross's post about suitcase trouble opened my eyes to something that I had been unaware of previously. Maybe I'm the only one who was clueless, but here we go nonetheless.

Those connections on the suitcase bottom are every bit as useful as inputs as they are as outputs. So if your preamp is fritzed, or oyu're missing the magic cord, get yourself some kind of stereo FX box with some input gain (I have a Lexicon MPX100, it has input and output gain, WOO!), hook up the harp output to the input of your box (by the FX send works just fine) and run the stereo outs to the pair of in/outs in the suitcase bottom, and you've routed around your preamp! No modding needed at all.

And for further amusement, a Mark II name rail has a slot pre cut that's not quite wide enough to take in a 19" rack box (mine are mostly 17" in the chassis) , unless maybe you mounted it from the back side.

Damn, before I paid someone 60 bucks for a magic suitcase preamp cable, I'd definitely entertain the notion of bypassing the whole preamp package by installing a used reverb unit for the same bucks (I paid 30 bucks for my box).

I just watched the last two minutes of an ebay auction where a mint 200A went from 1425 to a final sale price of $1,762.99.

Unbelieveable.

http://cgi.ebay.com/19-NOS-Fender-Rhodes-Piano-Tines-5-3-4-Inches-Very-Rare_W0QQitemZ270214709173QQihZ017QQcategoryZ16220QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Can someone explain that to me? How would an end user mount these? Just beat it into the hole?

http://cgi.ebay.com/MASSIVE-Lot-of-Vintage-Fender-Rhodes-TINES-65_W0QQitemZ130196512622QQihZ003QQcategoryZ1289QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

No bids, shocking.

Maybe he'd have better luck if he included a tine stretcher with the package.  :roll:

anyone done this? I started to get a sound like frying bacon today. I've traced it to my volume pot. I'm wondering if a cleaning may alleviate the issue or am I better off replacing? Any experience you'd care to share would be appreciated, thank you.

Okay, there's one local to me, I'm thinking about it, what is the group's opinion of value on this rare beast? It's similar in concept to a CP80, acoustic piano with pickups instead of soundboard.

Plus side:
it's supposed to sound pretty good versus a CP80, I haven't played this one yet.
Has MIDI out (if it's got all the cables)

Minus side:
330 pounds (holy crap!)
probably impossible to source parts
will need tuning
might need regulating
330 pounds!

In no case would I pay more than 1000. One sold recently on ebay for 400, hard to know about the condition though. Any of you cats own one of these? Any of you tech types ever serviced one (I'm looking at you steveo)?

http://youtube.com/watch?v=npXO6QE2l0g

heads up:
http://cgi.ebay.com/LOT-Fender-RHODES-Piano-Brochures-Svc-Info-Mark-II-V-EP_W0QQitemZ330182977375QQihZ014QQcategoryZ38071QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

[Edit: updated title]

I'm getting one for a little bit of nothing later today.

Not being dissatisfied with my clean tone, I'm curious what if anything this box can do to improve on it.

I'll do some sound checks and post results here of course.

Edit: updated title

[input]

If you haven't already, please have a look at dimensions of tone in which I explain the background of what is going on here.

In part three, we'll try to measure the precise effect of the tone controls on a suitcase (sorry stage owners--it's what I have on hand).

To accomplish this, I recorded a test signal: a .wav file with 10 seconds of pink noise. Pink noise is widely used as a test signal since it has 1/f power distribution. You can translate this into a useful musical term--every octave contains the same amount of energy. I played the test file out of my audio interface and into the effect loop return of the suitcase preamp (and hence through the amp and modified speakers). I measured the response with a  Behringer ECM8000 reference microphone, which has a reasonably flat response curve (you can look up the specs if you like, but it is "flat enough" within 20Hz-20kHz). That signal was sampled back in my Edirol UA-25 at 48kHz and 24 bit sample size (as previous measurements). The graphs were produced with Audacity.

First let's examine the spectrum of the input signal. On a log-log scale, you'd expect 1/f to be a straight line.


Looking good. That's a 3dB/octave slope. Now let's have a peek at the output spectrum with the tone controls set flat:


I overlaid this and the others on the input curve for easy comparison. What can we observe?

• bass response falls off rapidly below 45Hz. Lowest note on a seventy-three is about 41 Hz.
  
• From say 100Hz to 3kHz, the response tracks 1/f pretty well overall.
  
• There are a couple very prominent notches in the spectrum at 359Hz (F4) and 1423Hz (F6)
  
• Above 5kHz things roll off quite a bit more steeply than 3dB/octave. Yours will roll off even faster since I modified mine.
  

So the suitcase bottom colors the sound substantially. We knew that already, but this gives us a way to visualize it. The bass is boosted somewhat even though the tone controls are set flat.

Next I pegged the bass tone control. I was a little surprised at the resulting response:


You get a 6dB hump centered at around 91 Hz that's a couple octaves wide. What surprised me was the apparent cut in treble that came along for the ride. You wouldn't expect that from a graphic equalizer--I never considered that the bass boost may also cut treble.

Next I pegged the treble.


This seemed to take effect in the octave between 3kHz and 6kHz entirely. The EQ may actually have a wider band, but the rolloff of the speakers is swamping any effect that would have. And look at that, a corresponding bass cut (look at 95Hz--we lost 6db compared to the flat curve). Very interesting.

And then I pegged both bass and treble:


Interestingly, but not surprisingly now that we've seen each control separately, this results in something a lot like the flat curve, but with the middle dropped out a bit. I don't view this as a practical setting, I just threw it in for interest.

I'm working on getting you a good sound file to listen to the coloration (music, not pink noise). Bear with me while I work out mic placement issues.

Let me know if this kind of article is useful.

I have to blame dnarkosis for this--he asked me some questions that got me thinking along these lines, and several of our discussions lead to the same conclusion. Here I'll develop the concept behind the project.

Imagine an "ideal" system: an arrangement of speakers capable of producing the full tonal range and dynamic range of the Rhodes at realistic modern stage volumes without contributing its own color to the sound. It would be driven by an arrangement of amplifiers that can deliver the full dynamic range of a Rhodes at realistic stage volumes with high fidelity without coloring the sound. All real systems involve compromises that make them deviate from this ideal.

The classic suitcase bottom has 4 12" speakers driven by 2 40W or 50W amps. It has a frequency response that is limited by the choice of drivers. I'm working on an analysis of the limitations of the amp design. In either case, I have just obtained the equipment necessary to measure the frequency response of the suitcase bottom, so stay tuned for a thread where I describe in detail how it deviates from the above described ideal.

Here I'll stop and point out that my view is that intentional coloration of the sound should be accomplished before the signal is presented to the amplifier. I've encountered those who don't share that view, and I don't necessarily care to argue the point. I'm not considering whether or not a coloration due to the design of the classic suitcase is desirable or appealing, just that it is non-ideal.

I arrived at this point of view suddenly when I had the chance to listen to a direct recording of my suitcase. At that point, the degree to which the suitcase bottom colors the sound was revealed to me. I'll post some files later to help you all perceive the difference.

Anyhow, the design I have in mind takes shape as follows:

• Active crossover (Linkwitz-Riley design probably)
  
• two bi-amped channels (to support the stereo tremolo feature fully), totalling 4 channels at 60W
  
• eight 10" drivers
  
• four compression drivers
  
• same form factor as the classic suitcase bottom
  

Some of the "why" behind these choices:
Why biamp? I think that the main defect in the classic suitcase bottom is an indistinct lower midrange. Close voicings sound bad in the area south of middle C or so. This is less prominent on direct recordings, so I conclude it's coloration from the suitcase. I aim to measure the effects, but for now, I'm working on the assumption that there's intermodulation distortion which I can alleviate by a biamp strategy. Active crossover of the signal is required to biamp effectively. I will attempt to measure intermodulation distortion of the classic suitcase bottom, so stay tuned (plus I'll explain it along the way).

Why 10" drivers? I worked with bass players who convinced me that 10" drivers are the way to go. drivers with response down to 44Hz are available, so I won't have to sacrifice low end, yet the lighter mass of a 10" will make it more responsive in the mids. I feel like this supports a flat response close to the above ideal.

Why 60Wx4? Headroom. End of story. No actually, that's not the end. I think the dynamic range is being curtailed by a classic suitcase. I don't like playing loud, but I do like my dynamic range. I want to be able to peak loud for transients without clipping under all reasonable stage conditions.

Why compression drivers? Where's your treble knob set right now?

This is the beginning of the discussion. I have a lot of measurements in mind before I finalize any of the design. It's all up for grabs. But the basic premise is that excellent design + modern components + correct goals + attention to performance details should result in a superior system that gives an extraordinary electric piano sound.