Author Topic: Advice and help with piano bass restoration  (Read 175 times)

Offline mvanmanen

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Advice and help with piano bass restoration
« on: September 08, 2017, 09:50:58 AM »
I have just started restoring a 1960s Fender Rhodes piano bass. It was in pretty rough shape when I brought it home with half of the keys sticking but after a really good clean, easing of brushing, adjustment of a couple guide pins, removal of deformed damper felts, etc. the action is even and playable. My questions going forward:

- About half of the felt hammer tips are quite grooved yet at least do not seem to get stuck on the tines, the others are really in fine condition. Should I replace these? And if so where does one find these triangular wedges of felt? I know vintage vibe has some bass hammers but I imagine I can just replace the felt? (https://www.vintagevibe.com/collections/fender-rhodes-authentic-1960s-parts/products/fender-rhodes-1966-bass-hammers?variant=899469463). I know my piano tech's will lightly sand/shave felt hammers for voicing on a piano but to remove the groove I fear I would remove too much felt and also wonder if this is appropriate.

- I get great volume directly off the RCA plug but very diminished volume off the name rail. I have tried multiple amps to see whether this is an impedance issue but so far it is consistent across all amps. I have never had such issues with the output off my other rhodes but also have never owned a 1960s rhodes before. I have cleaned the pots and checked the soldering connections. Any other ideas before I start replacing parts?

- The action while even is not as lovely as my other rhodes that I have tweaked. I have never owned a 1960s rhodes before. Should I adjust my expectations?

thanks so much,

Michael
Wurlitzer 200a
Wurlitzer 145
Fender Rhodes (1971, 1975, 1980)
Hohner Clavinet Pianet Duo
Hohner Clavinet D6s
Hohner Pianet T
Hohner Pianet N
Hammond B3

Yamaha CP4
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Offline sean

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Re: Advice and help with piano bass restoration
« Reply #1 on: September 08, 2017, 06:26:32 PM »

Michael,

How could you do this to us?   No pictures?  This is something we gotta see.  We will drool over it even in crusty and dusty condition.  Please.

In addition to the standard glamour shots, I would really like to see a photo of the circuit that is on the back of the name rail (volume and tone).  Can you read or measure the component values?

Thanks,

Sean


Offline mvanmanen

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Re: Advice and help with piano bass restoration
« Reply #2 on: September 08, 2017, 08:47:44 PM »
By pots it dates to 1966....it's sitting in front of my Fender Showman and cabinet for size and style.
Need to measure values still
Wurlitzer 200a
Wurlitzer 145
Fender Rhodes (1971, 1975, 1980)
Hohner Clavinet Pianet Duo
Hohner Clavinet D6s
Hohner Pianet T
Hohner Pianet N
Hammond B3

Yamaha CP4
Hammond SK1

Offline mvanmanen

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Re: Advice and help with piano bass restoration
« Reply #3 on: September 09, 2017, 07:15:06 PM »
Is this normal...when I plug the piano bass into an amp off the RCA I get good volume...yet when I plug a second rhodes into the second input of the same amp while the bass bass remains connected instant major volume loss of the piano bass yet the other rhodes maintains its volume.

If this is not normal...what might the problem be?

thanks so much,

Michael

Wurlitzer 200a
Wurlitzer 145
Fender Rhodes (1971, 1975, 1980)
Hohner Clavinet Pianet Duo
Hohner Clavinet D6s
Hohner Pianet T
Hohner Pianet N
Hammond B3

Yamaha CP4
Hammond SK1

Offline sean

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Re: Advice and help with piano bass restoration
« Reply #4 on: September 11, 2017, 12:29:57 PM »


This is "normal" for a Fender Showman (and lots of amps that have a resistor divider as the "mixer" before the first input tube.  It works okay for high-impedance sources, but sucks for low-impedance sources.

Since your piano bass pickup rail has a total resistance between 600 and 700 Ohms, you have a problem.

You might get inaudibly better results by plugging the Piano Bass into input #2 instead of input #1, but I doubt that fixes the problem (because a Rhodes 73 in input #1 still provides less than 1500 Ohms). 

You should have no problem if you plug one instrument into the normal input and the other into the vibrato input (because they would be going into totally separate tubes).

The other solution is to put a buffer stage between the Piano Bass and the amp.  MXR Micro Amp or similar would be fine.  You don't need the gain, you just need the isolation and high output impedance.

If you plug the two instruments into a little desktop mixer (cheap or otherwise), you will find that the problem goes away.

Sean



Offline sean

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Re: Advice and help with piano bass restoration
« Reply #5 on: September 11, 2017, 12:41:56 PM »

Oh, I forgot to say:

The Piano Bass looks a lot nicer than your original post led me to suspect.  You did a good job cleaning it up.

The hammer felts don't look so bad (but it is not a high-res closeup photo).  If VV doesn't make replacements, maybe you can buy the stock felt and rig up a razor-blade guillotine.  No wait!  I have a better idea: use a deli-meat slicer to cut the felts.  No wait!  I have an even better idea:  beg VV to cut custom felts for you.  Hire a hypnotist to convince Chris to do it.

Sean

Offline mvanmanen

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Re: Advice and help with piano bass restoration
« Reply #6 on: September 11, 2017, 01:06:34 PM »
Thanks Sean. Yeah. I have already spent quite a bit of time cleaning it up. Everything is working great coming off the harp recognizing I need to be sensitive to where I am plugging it.  I think the only thing at this point it really needs is whatever is going on with the name rail fixed and new damper felts for a few notes although I am inclined to just replace all the damper felts. I sent VV an email so will see what they say.

BTW working a piano bass is so much easier than a full 73 or 88. Fewer tines to clean, tune, and voice, less weight to lift and surface area to clean, etc....
Wurlitzer 200a
Wurlitzer 145
Fender Rhodes (1971, 1975, 1980)
Hohner Clavinet Pianet Duo
Hohner Clavinet D6s
Hohner Pianet T
Hohner Pianet N
Hammond B3

Yamaha CP4
Hammond SK1

Offline mvanmanen

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Re: Advice and help with piano bass restoration
« Reply #7 on: September 11, 2017, 10:47:29 PM »
For the name rail both pots are 250K and the three caps are all 100nF. The name rail seems to pass the signal from other audio fine so perhaps all is just the way it is supposed to be?
I am just amazed at volume loss when the piano bass itself goes through the name rail in advance of the amp. It's like there is an impedance mismatch between the harp and the name rail.
Wurlitzer 200a
Wurlitzer 145
Fender Rhodes (1971, 1975, 1980)
Hohner Clavinet Pianet Duo
Hohner Clavinet D6s
Hohner Pianet T
Hohner Pianet N
Hammond B3

Yamaha CP4
Hammond SK1

Offline mvanmanen

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Re: Advice and help with piano bass restoration
« Reply #8 on: September 13, 2017, 02:36:09 AM »
Problem solved...I measured the resistance of all the pickups and one was way off. The wires are corroded. Anyone have an extra green 1960s pickup I can buy off them? I only need one ;)
Wurlitzer 200a
Wurlitzer 145
Fender Rhodes (1971, 1975, 1980)
Hohner Clavinet Pianet Duo
Hohner Clavinet D6s
Hohner Pianet T
Hohner Pianet N
Hammond B3

Yamaha CP4
Hammond SK1

Offline pianotuner steveo

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Re: Advice and help with piano bass restoration
« Reply #9 on: September 16, 2017, 06:45:51 AM »
@Sean, where would you buy the felt to use? Do you know of a place to get it? Hammer felt is not the same as other piano felt. It is very dense, hard, etc. It is not like soft damper felt.
1960 Wurlitzer model 700 EP
1968 Gibson G101 Combo organ
1975 Rhodes Piano Bass
1979 Wurlitzer 206A EP
1980 Wurlitzer 200A EP
1980 Wurlitzer 270 Butterfly Grand
2000 Yamaha acoustic piano
2004 Hammond XK3
2009 73A Rhodes Mark 7
2009 Korg SV-1 73
....and a few guitars...

Offline sean

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Re: Advice and help with piano bass restoration
« Reply #10 on: September 16, 2017, 12:11:58 PM »


Doesn't VandaKing sell to the unwashed public?

Sean