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No I thought you were referencing the intro to "Butterfly" from a particular Herbie Hancock bootleg, but I guess it's the album "Flood" instead of the bootleg I was quoting from.

a few seconds from around 4:57 to 5:08 or so, you do a really nice run getting out of the chord.

Nice, I'm curious what you used for the strings sounds? Sounds quite like the 70s.

A little bit may rub off on you...



Added: ooh, just got to the susb9 chord, very nice.

I wonder if it's worth having a UK specific section on these forums, at least for buying / selling.  Not sure how many UK Rhodes players are on here, but getting parts is a real pain so sharing what we have & combining postage etc would be useful.

I think it's a great idea myself.

OK, I will have to post the writeup later, but I have a lot of stuff done with those files, thanks.

The answer seems to be harmonic content alone.

Or am I just overthinking this.

I kind of started down a path that leads where you are heading. Here's some threads to look at:
http://ep-forum.com/smf/index.php?topic=3263.0
http://ep-forum.com/smf/index.php?topic=3264.0
http://ep-forum.com/smf/index.php?topic=3288.0

I didn't really get around to trying to measure the "bark dimension" but the same kind of things could apply.

I think your hypothesis is pretty good--the pickups are linear to a point, and beyond that point are nonlinearities, the desirable effect of which is known as "bark." This agrees with the shared experience of the enthusiast community, but I don't know that any of us have accounted for the mechanism very precisely. It would be interesting to see measurements (waveforms and spectrograms) from "non-barking" and "barking" signals and look for the differences. I expect it will show as more harmonic content, but the higher order stuff probably decays fast, so something that can generate a waterfall plot would probably visualize it best.

I would chip in but I am unfortunately backlogged with a bunch of work that I have to get done. If someone can post up "barkful" and "barkless" examples of the same note, I can do the signal analysis, I just can't set up to go collecting the sounds myself right now.

The term is "class compliant" if it will just work with the PC.  The manual should answer this, but I am having problems reading it.

Most external audio interfaces have a midi port, I was referring to that as opposed to some onboard audio chip.

What I wasn't clear on, and I can't download the manual right now, is will the Privia connect straight in via USB. So I sort of assumed that's what he original poster wanted to accomplish, then offered my "use an interface" as a workaround, since it moves the problem to "get an interface with a driver for your flavor of operating system" instead of "can't get a 32-bit Privia driver."

Welcome aboard--it should be possible to get a midi interface of your choice installed. You'll need to pick one with support for your operating system. But then, since MIDI is a standard interconnect, your Privia can connect to your PC using a 5-pin DIN cable, and it won't need a driver of any sort.

We had a fairly technical thread going about impedance matching I'll try to search that up.

I think that the pickup configuration is sort of a compromise, and I think that one of the goals of the compromise was in fact to address "why (WHY??) would Fender design an instrument that wouldn't work with their amplifiers?" The service manual refers to the change in pickup configuration as producing a hotter output signal. I'm working out a way to test if there are other preferable characteristics to the old wiring scheme (parallel groups of six--the later harps are wired as parallel groups of three).

I don't fool with guitar amps in my signal chain, and accordingly I am used to really high input impedance, so I haven't seen the kind of tone- and level-sucking effects that a lot of people describe when they wire up to a guitar amp with a low(ish) input impedance.

But won't this suffer from the same problem as my tube amp, namely, that the volume control will essentially short out those 4 Mohm resistors across the preamp input to ground?

The point of it is to act as a buffer. Being a JFET it will have a really high input impedance, which is desirable specifically so it doesn't load the pickups. At higher impedance it will draw less current, so you're losing less energy heating up components in the signal path.

To the extent that I'm anyone, no.

Here's a really low-cost solution (DIY):
http://scotthelmke.com/Mint-box-buffer.html

I guess I'll offer that if it will fit in the hole it should be good. Those fuses are a standard size.  3AG size is 1-1/4" x 1/4".

You may also be able to get that locally at an auto parts store. Generically it's a panel mount fuse holder for 3AG fuses.

Another source:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=071-510

I don't have a Mark II suitcase, does this look about right?
http://www.allelectronics.com/make-a-store/item/FHPM-31/3AG-PANEL-MOUNT-FUSE-HOLDER/1.html

That 4-pin cable can be a pain. Possibly you didn't get it seated the first time.

The cable from preamp to suitcase can be a failure too. Check it for continuity with a multimeter--it is wired straight-through.

Moved at the poster's request...

I have a completely different approach. I have the old version of this passive direct box, which allows you to get from speaker level to line level cleanly, quietly, and without modifying the piano.

What wah pedal are you using there?

My boss (guitar player, how's that for irony) was considering buying it.

http://kansascity.craigslist.org/msg/2945189662.html

I have a Wurlitzer 111 electric piano. It powers up and plays, but has 1 key that doesn't sound (d3), and two that you have to play hard to hear (f1 & g4). Other than that it powers up and plays as expected. It is an old tube amplified system with a speaker in the back. The volume knob has static when it's turned. I've cleaned it up some since these pictures were taken. I blew all the dust out of the inside and between the keys and dusted it off overall. This would make a good project for someone who wants the old wurli sound or an investment to rebuild and sell for quite a bit of money. Vintagevibe.com sells all the stuff you need to fix it up. Price is negotiable, cash and local only.

I have a D6 clav on top of mine, I'd say that's well in excess of 50lb.

Works just fine.

However, your gain structure may be a little different than what you posted. The FX loop is before the preamp, so you don't really get a substantial gain boost from that pedal, you get an increase in harmonic content of the signal due to the distortion it adds. So you will very likely need to use comparable preamp gain to what you use without the pedal.

I have a morley wah with a boost knob, and that's a little different, it does add gain, so I have to carefully stage gain through the signal chain. I like to use pedals like that in the FX loop of my mixer, which makes it harder to shoot yourself in the foot.

I'd be really interested if there's any perceptible difference to using a super low cost DIY preamp with a JFET like this one:
http://www.buildmyelectricguitar.com/electric-guitar/misc-electric-guitar/piezo-jfet-preamplifier-mpf102.html


Asking my question another way, does the DI box have any intrinsic goodness, or is it really just the impedance matching that allows the inherent goodness of the Rhodes tone generator to come through?


I have my suspicions, but it would be interesting to experimentally confirm.

Your design for power will be a variation on the reference design shown here on page 12:

http://www.fairchildsemi.com/ds/LM/LM7915.pdf

What they don't show is that you get your input voltage from a center tapped transformer with the proper current rating, and rectifiers to get from AC to DC.

If you haven't built a DC power supply before, I'd suggest getting familiar with it by doing a test project (they aren't expensive).

The basics will be the same, but please get your mistakes out of the way on a dry run before hooking up your Rhodes preamp.

The transformer will turn line AC into a lower AC voltage. Center tapped transformer gives you two AC waveforms with opposite polarity referenced to a common ground (the center tap).

Rectifiers turn that AC into DC with a large ripple.

Filter capacitors turn that into DC with a smaller ripple.

That DC with a manageably small ripple is what you feed to your IC regulators as shown in the PDF datasheet I linked. All in all you are talking about ten bucks worth of parts or so.

Selecting your filter caps is a matter of tradeoff between the required "flatness" of your DC waveform and stress on the transformer and rectifier due to the large inrrush current possible when you start up the supply. Bigger capacitance values are good, because they give you lower ripple out, but bad because they take more energy to charge, whcih makes the startup current of your supply big (and you wind up buying bigger components to accomodate it, or replacing them when they burn out). So pick caps that are "big enough" but not bigger.

It sure helps if you have a scope to look at the voltage waveform, but you can do it without. Choosing the filter caps is the only really fiddly part of it.

Other forum members may choose to add to (or throw rocks at) my explanation.

Most people don't properly account for confirmation bias when they do comparative listening. It's not all that easy, but there are tools to help.

http://www.homebrewedmusic.com/2009/04/22/abx-testing-and-a-new-audio-interface/
http://www.hydrogenaudio.org/forums/index.php?showtopic=16295

DJ Steveo

Did she mention what she paid for the piano? I'm curious about market value on these.

The market for entry level is so much larger than the market for advanced level.

I tend to prefer a mixer for this trick. I heard Herbie playing this setup on a bootleg (the Omaha one) and went out to recreate it. He did a typical clav lick, but with the left hand part on Rhodes, while both were routed trough the same wah. I call it the sixteen funkiest measures ever. I'll try to post a clip later.

But anyway, having the ability to mix dry and wet makes it sooo much better, so I think a mixer is the best way to go after this. A little dry clav in with the wah clav makes it a lot more punchy.

Before a certain date (I'll get corrected for sure if I guess at it, but early 70's) you didn't have an FX loop on the name rail. So if you wanted to drive your FX with a signal before attenuation by the volume knob, you had to pull right off the harp.

Way back when I wrote up some blab about frequency response of the suitcase bottom:

http://ep-forum.com/smf/index.php?topic=3288.0

Synopsis: the suitcase bottom colors tone substantially.

I've got some better analysis tools now, I may revisit this topic.

I doubt you'll find much similarity in tone actually. I'm not personally a huge tube distortion fan, but many people swear by that. You'll really have to just try and see what meets your musical needs best. The purchase of the twin probably isn't a horrible mistake--it's a sought after piece of gear that ought to hold value well even if you don't end up needing it for your rig.

So at worst it's a detour, not a mistake.

Here's a handy LED calculator for this exact purpose: http://led.linear1.org/1led.wiz

In a 200, I typically wire the positive leg of indicator LED to the 44V supply at the positive end of C6 (the big 1000mF one all the way on the right side of the board) or the nearby diode that is at the same junction.  The negative side of the LED can go to any convenient ground point.

So, in this example the supply voltage is 44V, the LED forward voltage is 2V, and the forward current is 25mA.  Plug it all into the calculator and you will see you need a 1.8 kOhm, 2W resistor in series with your chosen LED. (there is an actual formula you can learn for this, if you want to do all the math yourself.  It's not very complicated but the calculator simplifies things for those who don't want to get into the math)

A 2kOhm resistor would also work fine if it's easier to acquire.  The wattage rating is important as it is dissipating the excess current.  If you put a 1/4W resistor in there it's going to fry.

Also useful info: you can add the power ratings for resistors in parallel (but not the resistance). So two 1W 3.7kohm in parallel could be easier to find than the single 2W.

Thanks for the report. Sometimes, you just gotta try it yourself and see if the magic happens. Glad it worked out for you.

If you have a piece of recording software, it is probably the VST host you need to run these (Audacity doesn't support the VST standard edit: looks like newer versions do support VST). VST instruments are loadable only if you have a VST host, but once you do, there's about a zillion and a half things to play with, many of which are excellent and free.

I was worried this was going to be a senior citizen hookup thread. 

I wouldn't consider an escapement adjustment as maintenance really, it's more setup. So I wouldn't make a change unless you had a specific goal in mind for that change. Players will have vastly differing preferences in terms of action, and as long as your preference doesn't change, I say the setup is to tailor the feel to the individual player.

Having said that, if you're breaking tines, you ought to increase your escapement. I find myself in that position right now; I need to go back and redo my setup since I've had about 5 tine failures (I'm not breaking them, just making them go irreparably flat) over the last year. That's too expensive not to do something about it.

Just about anything can be worth USD 200-400 as a parts dog these days.

Well, I replaced them with parts I bought on ebay.

But generally, I'd look at it like a dentist:
* remove the decay (cig burns)
* fill the resulting gap with matching black resin
* let it cure and set up
* level out the repair
* finish up with sandpaper, rubbing compound, buffing compound, then polish

I had mine (a 462) "permanently" wired into mine for a while.

http://ep-forum.com/smf/index.php?topic=3454.msg14681#msg14681 (includes demo)

I decided I liked the lower noise I got without it--maybe the pedal would be preferable to the rack since it's DC powered. I'd buy the pedal, but I wouldn't pay the new price, I'd look for a used one.

Tuning will remove low mid mud better, and it's more or less free.

I'd probably clean it with a light detergent first, and then use that product to dress it if it still lacked enough gloss for you. To me it doesn't look right shiny, and I would not want to get that stuff on my hands.

Just my opinion though--that stuff won't hurt the tolex.

Moved.

I'd personally try making the bending/creasing jig out of a 2x4 scrap with a groove routed in it. But that's because I have that stuff lying around in my shop (those aren't intrinsically superior tools). I don't think it needs to be highly complex.

Welcome aboard, Ben. Nice having you in the community.

Actually an FX loop on the namerail is on front of the preamp, these jacks are behind it, but yeah.

I've often said that I don't really feel I truly own a vintage keyboard until I've had it in pieces all over my basement. 

Rob's corollary to Alan's theorem:
You'll be reliably able to spot a parts dog after you buy a parts dog.

So the jacks on the cabinet labeled "Preamp Output" are actually inputs? The labels would be saying "This is where you plug in the output of the preamp." I can see how a "Preamp Input" label would be just as confusing (implying that you would be plugging in to a hypothetical preamp inside of the cabinet).

They are both inputs and outputs.

You have the same thing on suitcase bottoms after a certain date as well. I have used them as signal to record stereo direct. You can also send audio to the amps by connecting a signal to them, so they function as both.

Here's a detailed signal chain for stage versus suitcase (or satellite-equipped stage with preamp) for your reference.

Stage piano harp ----> passive tone controls on namerail ----> your external amp (which includes a preamp stage almost certainly, and probably tone controls)

Suitcase piano harp ----> active preamp on namerail ----> stereo out to suitcase amp (2 channels) via the 4-pin cable

The preamp is not just a gain stage. It performs an important function in terms of impedance matching the piano to the amplifiers it's connected to. Tone can be affected if the piano is connected to a low input impedance amp, and the preamp corrects that issue (which is far less of an issue with modern amps than is was when Rhodes pianos were prevalent). You also get active tone controls (which can boost, not just cut) and the stereo tremolo from the stock preamp.  Guitar amps have preamp stages built into them for pretty much the same reason.

1) that connector is 4-pin DIN, yes it's equivalent to suitcases of that same era. Cinch-Jones was used on earlier suitcases.

2) cable is just 4 wires, straight through. Hardest part is sourcing the DIN plugs. You probably want a right-angle one for the piano side--this however assumes you have a preamp in the top-- power to the preamp is provided by the master (slave is the same cabinet minus the 4-pin DIN jack and hence the preamp power supply)

3) You can drive this cabinet from your stage by connecting a guitar cord to either of the preamp outputs, as counter-intuitive as that seems--they are just normalled jacks in parallel with the connection from each preamp out.

4) which you didn't ask, the slave output is just the second channel from the preamp line-level signal to drive a second satellite cabinet (master or slave). It takes two to get the full stereo effect of the preamp's vibrato/tremolo.

The buyer's guide link in my signature should be helpful, although I'm not as comfortable with pricing in the UK market as I am in the US. The maintenance and checkout info should help you though.

Cheers Electroharmony, I put your post in a sticky thread, this is a big help.

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