Messages

Hi :-)

Remember that you will allways need some force to lift up the damper arm. The damper arm is spring-loaded, so maybe you could reduce the tension there a bit. The drawback of this is that the damping itself will be not that instand / accurate as before.

Jenzz

Hi :-)

There are some interresting pics from the inside Mk8 at NAMM on the german 'Musikerboard'...


https://www.musiker-board.de/threads/namm-2023-the-transition.740533/post-9502871



Jenzz

Hi :-)

You have to cut the sustain dovel down to lenghts of that of a stage piano, then insert this guide cup:

https://www.vintagevibe.com/products/fender-rhodes-sustain-guide-cup


Now you can use the normal stage pedal...


A hotfix will be to drill a hole to the bottom of the dovel to fit the size of the pushrod.



Jenzz

Hi :-)

VV felts are harder / more compressed than the originals, you did nothing wrong....

Jenzz

Hi .-)

Looking at the pics, it seems that the leads of the diodes have melt into the housing of silver caps, probably touching the inside foil?

Jenzz

Why not using the old / original screws?


Are they the thick ones (4,2mm) or the thin ones (3,45mm) diameter below the head?


Jenzz

Hi :-)

You should change these fuses to the standard 5x20mm + holder. You can use 1,6A (which is the nearest type in EU) slow-blo. Since the voltages are not high, voltage rating doesn't matter here.

Jenzz

.... i figured it sounded very much like my behringer vp which is a clone of the small stone, really need to buy the real deal at some point,

Hi :-)

I would give the VP an try...

Look for the the Moot Booxle video on YT where he compares the VP and a V3 Small Stone. I think the VP sounds 'spot on'.

Jenzz

Hi :-)

Sounds pretty much like a vintage EHX Small Stone Phaser with color switch in 'Up'-Position... And some volume tweaking...

Jenzz

Hi :-)

This problem in very common. You need a Line-Iso-Box.

The Wurlitzer's signal ground is tied to the pianos earth connection (3-prong connector).
Mostly all tube amps do the same, signal ground is tied to earth (for saftey reasons / High-Voltage).

If you connect a Wurlitzer to a tube amp, you will close the ground loop via the shield of the audio cable.

So, you need someting to 'isolate' the signal path's ground. This can be done by a line iso-box (1:1 audio transformer)... Palmer PLI-01, PLI-05

Jenzz

Hi :-)

The diodes have to handle the current of the power amp, so i would recommend something like the 1N5401 - 1N5407.

Jenzz

Hi + welcome :-)

Keep two things in mind:

The 5 hignest notes have no dampers, so there will always be some kind of 'faint ringing' when notes are struck.

When the pedal is released, all reeds are bend a bit downwards due to the tension of the sustain / damper arm mechanism. When you hit the pedal hard, the releasing damper felts will pull away from the reeds, causing them to ring because of their own bending tension.

The, this phenomenon is kind of normal to some degree.

Do you have a sound file?

Jenzz .-)

Pre-tuned doesn't mean 'exact'.

This is why i allways sale pre-tuned reeds a bit too low.

The machining seems to be more precise on the older models up to the 200... The worst machining is on the german models 201 / 300... It seems to me that the B-Stock parts were sent over here ;-)

It's the experience from over the years and what i see / measured here in the workshop... Maybe different from yours.


regards, Jenzz

Hi :-)

This is common due to the age of the piano. The pedestal felts and/or the key rest felt will be compressed to some degree over +45 years. I personally would leave this as it is...

The miracle mod doesn't adress this issue, it changes more of the overall feel of the action.



Jenzz

It would appear my balance rail is tilted back quite a few degrees. I'm not sure what to do about that. Any help would be greatly appreciated.

Hi :-)

This is pretty normal and the way its supposed to be.

See this pic from the manual:

You cannot view this attachment.

Jenzz

Another German related subject I'd like to discuss, is about those, almost original, T/M/Duo pads Mr. Werner Bothe was producing, but not anymore. I'd like, for future reference, to be able to produce/get my owns too as i have easy access to labs and small factories with CNCs, Laser cutters/3d printers,plastic molding machines etc. Seems it's a kind of silicone rubber square profile but i guess special attention and experiment is required to find the exact one with appropriate similar sticky properties.
 

Hi :-)

The pads fron Werner Bothe (he is just 30km from me) were made of the original casting compund. But for some reason, he made the pads bigger than the originals (more depth).

This causes them to stick not as good as the originals because of the slight bending of the reed, so they won't touch the reed at the same pressure with their entire surface.

Jenzz

Hi .-)

Since the treble reeds are very stiff, chances are that the hammer levers are bend in that area. The material is relatively soft to allow bending / adjustment.

BTW: I remmoned a re-cap job on the wholw instrument. Esp. the 'golden' Siemens caps are prone to leakage after nearly +45 years. Also keep in mind that the power amp chips are very hard to find.

(...last Pianet M i had in for service had a blown power amp chip + the speaker was fried due to a defective cap)

Jenzz

Hi :-)

Did you check this with dampers or with dampers complete off?

Since there are 32 reeds on every aluminum cast, there is always a chance that there are some reeds in harmonical conjuction with the 'main' note (octaves, quarts, fifths), swinging out-of-phase with all dampers off. This will remove energy from the 'main' note and shortens sustain, too.

Reed screw... Be sure that it is thight to a certain amount, not just snug. Otherwise the spring-action of the washer will not work as supposed. This can reduce sustain.


Jenzz

The new Roland JC-40 has a complete stereo signal path...

Jenzz

Roland JC 120H

Jenzz

Hi :-)

The Dyno filter has a kind of two-way signal path. 'Normal' mixes the unaffected signal to the output.

The other path runs into a fixed mid-cut, then into a passive Fender-style Bass/Treble network. Because of this, the volume can got to 0 when kompletely turned CCW. Anonthe buffer takes the signal to the output mix.

The stereo tremolo might give some impression of pitch shift / vibrato, because the signal source 'moves' in the stereo field.

Jenzz

Hi .-)

Keep in mind that the top e hammerflange is not part of a 12-piece hammer flange. To achieve the 73th note, this is a single flange with its own screw. Since this piece is cut from a former 12-piece flange, the securing pins at the bottom are only on one side. This will cause the flange to have a lot of side-play if the screw is not tight.

Jenzz

Hi .-)

As Peter suggests, the easy way will be to move the string.

The hard way is to loosen the PUs nuts, then they can be moved side-to-side slightly due to the oval / long hole. But then you have to be secure that there is no string over any of all gaps. For even results, check both lower and upper PU.

Jenzz

Hi .-)

Yes, i know that the edge is a machined part, but i have seen these tolerances here over 30 years. There are a lot of inaccurate machined casts out there...

Jenzz

Hi .-)

The idea is great, but doesn't work in real live, or is kind of 'random'.

After doing over 100 Wurlitzers, i can say: The distance from the reed-bolt thread inside the aluminum casting to the corner where the reed 'leaves' the supporting edge differs from cast to cast by roundabout +/-1,5mm.

So, tuning with another fixture than the 'real' cast (where the reed will be mounted to) will be only a approx. in tuning in most cases.

Jenzz

Hi:

Is it a 100W or a 80W Peterson model? Note that the Peterson preamp has a 5kHz lowpass filter in the signal path, so you won't get that much 'sparkle' anyway...

Do you have a sample of the actual sound?

Jenzz

Hi .-)

Is it a 73 or 88?

Are you checking directly from the harp or incl. preamp / cabinet?



Jenzz

Hi .-)

Due to dry-out, the wood of the case will bend towards the keys. This is more likely in the middle.

Jenzz

Hi .-)

Maybe the pickups magnet is reversed.

Nomally, all Rhodes pickups have the south pole towards the tine. (There was a short time at an erarly stage when they used north pole towards, the tine).

Maybe the magnet was reversed accidently during production. Having a south-front and north-front pickup side by side will cancel the fundametals, leaving you with a thin tone...

Another thing is the shape of the tine's tip. Be sure that it is propperly grinded to a plane surface. Avoid a 'fizzy', blurry tip from impropper cutting.

Jenzz

Hi .-)

If your Fender amp has a a high / low input option (like on a TwinReverb / ProReverb), allways choos the 'low' input. VV and the RetroFlyer are operating at line level at the outputs (if turned up full), so chances are you will overdrive the input stages of the amp when using the 'high' input, regardless of the volume setting at the Amp. This is because of the inner signal flow (input --> first gain stage --> EQ --> Volume --> 2nd gain stage -->....

Jenzz

Hi .-)

This red VV was once owned by board member 'Nitrofunk'... Looks like it is in good shape since 2013 :-)

Jenzz

Hi .-)

These are 2 different things:

There is nothing said about these damper arm / lever springs in the manual, so i came up with my own solution: I use a spring-balance to pull the damper arms up and bend these spings slightly so that the damper arms will not move up before reaching 40-50 gramms force / weight.

Refer to Fig. 2 from the manual... The damper regulating srew is the one that goes through to grommet. With key at rest, there should be an minimal play of 0,8mm between the top of the grommet and the bottom of the screw head.

To keep this measure is important esp. on the bass side. If the gap is to wide, the dampers will come down too close to the reed when the pedal is pressed. (Play and hold low A, then press the pedal and watch the damper arm moving, then you will understand...)

If you press a key, the whip pulls down the damper actuating rod / regulating screw combo. Therefore, the tension of the damper lever spring will alter key resistance.

If the lever spring is loose, the key will play light, if the lever spring is tight, the keys will play stiffer.

Jenzz

Hi .-)

Maybe the damper arm springs are too loose. The tension of these will add to the key resistance.
Also check for propper adjusment of the damper regulating screws. The gap to the grommet should be around 1mm max.

Jenzz

Hi :-)

What about the Rhodes-direct-to-Amp lovers? Do you consider an all-passive version?

regards, Jens :-)

Hi .-)

The 2 jacks on the front panel are the effects loop (top = send, bottom = return), not the outputs.

The 'external amp' jacks located on the cabinet can be used as outputs.

Jenzz

Hi .-)

Regarding hiss: The voltage regulator chip (723) is often noisy, because this chip was intended for industrial use, not esp. for audio. In most cases a 100nF film cap across R54 will reduce hiss audibly.

How is your audio measurement setup? It seems there is a ground loop between the piano and your setup, because you have some values even when the piano is off... This can only happen if a ground loop is present.

Jenzz

Hi .-)

In most cases, shielding is an issue... There are internal ground loops... The conductive paint inside the case bottom can loose connection to ground... Allways use shielded power cables inside the piano.

When the hood is open, the speakers see no air volumina to work on. If you close the hood, the air volimina inside the piano acts as in a closed speaker box. This will increase volume and bass, so the hum gets louder when the hood ist closed.

Jenzz 

Hi .-)

Yes, ols vactrols are prone to failiure when getting older... In most cases, the LDR element will drift out of spec.

The original vactrol seems to be not available anymore... I've used the VTL5C3 with good results.


Jenzz

Hi .-)

Allways use a Line-iso box to connect a Wurlitzer to an Amp, regardless of using the AUX or the Phones jack, otherwise grounding problems can occur. It is essential to have Amp ground an Piano ground separated (via the transformer inside the Line-iso box)

Palmer PLI-01 is a good example

Please note that the ground / sleeve contact of the Phones jack is not identical to the piano ground !
There is a 470 ohm resistor between ground and the sleeve contact for current limiting.
When using a line-iso box, this resistror doesn't matter.

Jenzz

Hi .-)

Just plug a plain TS plug into the Phones jack. This cuts off the internal speakers and automatically connects an internal load resistor to the amp's output (see schematic or open the piano, the resistor is located on a small soldering post directly at the Phones jack).

Jenzz

Hi .-)

14,5V is ok !

What about the value of the Tremolo Pot (50k) ? Is it wired correctly? What happens when you diconnect the wiper wire from TP5?

If TP5 is disconnected, the Tremolo pot should do nothing....

Jenzz

Hi .-)

This is not normal.... Did you check the 15V comimg from the regulator (TP 19 on the PCB)? There should be from 13,5 to roundabout 15,5 volts. If this voltage is low due to a bad regulator chip, signal headroom is decreased and distortion occurs...

Jenzz

Hi .-)

There are two trimpots on the 200A PCB...

One locatetd on the left front edge (max. volume adjustment), this one can be left as-is.

The second one (red dial mostly) on the left side in the back, right before the heat sink.  This is to adjust the average volume change / gain when tremolo is dialed in.

Jenzz

Hi .-)

The cap mod was published in german music magazine 'Fachblatt' back in the 70s (attachment)...

Adding the cap forms a resonant circuit, which enhances a certain frequency. If the cap value is propperly chosen, it can enhance the 'bell' attack tone or add some bite to the mids.

Jenzz

Yesss man! .-)

Jenzz

Maybe JD73 can tell us more about that? ;-)

Jenzz

Hi .-)

Janus / Haigler (5-Pin XLR connector cabinet): 4 Ohms (2x 8 ohms parallel) per channel

Peterson (4-Pin DIN / or Chinch-Jones connector cabinet): 16 Ohms (2x 32 ohms parallel or 2x 8 ohms in series) per channel


Jenzz

Current amp has some nasty crossover distortion, my tech couldn't find the problem so it's still there.

Hi .-)

Always check for proper bias. If its too low, you will get this crossover distortion.

Jenzz

Hi :-)

Ulf is always fiddling around with tremolo and sound 'per se', so he came up with some ideas and had some of the mods done himself.

3 jacks on the far left:

top: insert point between Vol pot and EQ
mid + bottom: preamp outputs

XLR: power supply only

Acc 1 + 2: Effects loop as usual

Ulf has the second version of the preamp (with the 'faint tremolo'). We corrected this by changing the switch to a DPDT... Cutting the depth pot + stopping the Vactrol LEDs (like on the 1st version).

Things near right of the panel:

Push/push switch for adding an additional set of caps to C8 and C20 for slower/smoother ramp curves.

Pot below the swich: This one is wired as an expression pedal / remote and connected to the jack on the far right of the panel. This is used to have the speed control of the Moog Phaser 'at hand' while playing.

Pot with the curve / line marking: Additional possibility of altering the tremolo curve: This is R17 of the schematics 'as a pot' (C11 cut out), so the curve can be altered from slice-type square to near triangle.

Jenzz

Hi .-)

TODAY !!

Ulf live with HR BigBand !

https://www.youtube.com/watch?v=t8fM4LG51G4


Jenzz