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Greetings all, for a long time I've been thinking about fabricating a back panel for my 720 (non-A/B - it has a 145/720 tube amp and the nameplate says only "720")

However I have never been able to find any image of any model 720 variant with a back panel in place.

Of course it's an assumption that it was even provided with a rear panel to begin with, but there are screw holes in places that make me suspect it was the case. As well, in my ancient digital copy of a xerox of the 700 service manual, there are a couple of grainy B&W photos which show there is indeed a back panel on that one. Those can be found on pages 700-4 and 700-5, where the procedure for removing the top cover is explained.

In all the digital copies of the 140/720 service manual I have seen, there is no mention of this component nor any photos.

My interest in this is both for the sake of keeping dust out of the action and reedbar area, possible enhancement of EMI shielding, as well as the possible changes in frequency response that come from having a more fully-enclosed speaker cabinet. My 720 has a 12" speaker, FWIW. Of course, port size and geometry can have an effect, and I'm not sure whether or not Wurlitzer would have concerned themselves with this or not.

I am guessing any full-size rear panel has to have some cutouts for hand-holds underneath each end of the dividing panel between the speaker/amp area and the action/reedbar area. As well as a cutaway for access to the amplifier. These together would provide some airflow for cooling of the amplifier, and I'm wondering if there were other features such as additional ventilation or access cutouts.

I could design something from scratch using these common sense notions but I am interested in seeing what the original design actually looked like. I also assume it was probably made from masonite paneling, 3-6mm thick, in keeping with the typical conventions of the era for back panels of audio electronics cabinetry, but being able to confirm any of this would be great.

Greetings all, been a long time since I posted.

I sort of took a break away from doing Wurlitzer repair but recently started taking on a few projects again, and trying to make progress on a few old ones.

I have a model 700 in for the typical damper felt replacement, along with a cleaning, action lube, and general setup work

When I went to reinstall the reed bar after working on the dampers, I noticed the two small braces that go from the front to the back were cracked. Either the casting had internal stresses that eventually fatigued (or it was dropped, or the reed bar screws were mis-adjusted and twisting it at some point in its life)

It seems to have less sustain than another 700 I used to own, and several 120s that I've worked on, although none of those pianos ever seemed to have a remarkable amount of sustain compared to the later models. Still working on setting up the action so maybe that could change, as the let-off is still way out of adjustment.

I'm inclined not to worry about fixing it (not a primary instrument or major studio piece for the client) but curious to know if anyone's ever encountered this or attempted a repair.

My guess is it could be carefully TIG welded (I am a welder), but I have no idea what the alloy is, and am concerned the casting might be somewhat porous leading to difficult welding. Dirt/oxidation is the enemy of a good Alu weld.

Physical distortion might also be introduced during the heating and cooling cycles, and the last thing I'd want is to warp the reed bar even further.

Has anyone tried the new sticky pads from Ken Rich yet?  I've just acquired a Pianet N that I think will need to have all the pads replaced.  I've seen the clavinet.com pads and they look like a new take on the construction & chemical composition, vs. the Ken Rich pads which seem at first glance to be faithful  recreations of the original design.

My understanding is that the original design is flawed since the foam in the middle of the "sandwich" will degrade over time, so it seems the Ken Rich pads are at risk of eventual failure in the same manner.  But I have also read that the clavinet.com pads are tricky to dial in, with some folks having to do a lot of keyshaft adjusting, or even adding a different kind of grease to get them to work right and sound good.

Anyone got any experience with both, or a well-informed opinion they'd like to share?

I have this crazy idea to electrify an old Jaymar toy piano.   I've seen people stick a transducer element on the soundboard, but I want to try a magnetic pickup system.  Different tone, and less feedback to deal with at higher volumes.

The tone generators in it are steel rods that are struck with a plastic hammer, so I think it will work with some creative pickup mounting.  There is room at the end of each rod for a pickup to be placed in much the same manner as you see on a Rhodes.

It's a 2-octave piano, so I would need 25 pickups all told.  That could get expensive, so I want to try just one first and see if it can generate a musical tone when amplified.  I would just use a guitar pickup as a test but I think the Rhodes pickup form-factor is ideal, being a single pole piece with an adjustable bracket for dialing in the response and voicing etc.

Anybody wanna huck me a single pickup for cheap so I can do some testing?  This will be the coolest Jaymar ever if it works out.

I just picked up another 140B that I'll be restoring, complete with the legs, sustain pedal, and fall cover - only thing is the latch pins for the fall cover are missing.  Anyone got a spare set they wanna let go?  Or at least some detailed photos and measurements so I can fabricate my own?

Also the knobs are a bit dinged up, anyone got a spare set in good shape or know where to get some?

I have three different Wurlitzers, and they all to some degree have worn/grooved hammer tips.  I am fine with the playability and sound of them as they are but I realize there could be some improvement to be gained here.

Vintage Vibe seems to advocate for reshaping with a dremel sander and then re-regulating.

In the 200/200A Service Manual, section 5D on the regulation procedure mentions reshaping hammers with a sandpaper file (similar to dremel, just done by hand), but also mentions "puffing" up the hammer crowns with a 75% methyl alcohol solution.

Has anyone tried this?  Haven't seen any info out there with regard to this technique.  I have dug through VV's youtube videos pretty extensively and never see them mention using alcohol on the hammers.

Just wondering because it seems less laborious than reshaping the felt and re-regulating the blow distance, let-off, etc. but I would love to hear others' thoughts before experimenting on my pianos.

Just saw this come up today:

http://www.ebay.com/itm/WURLITZER-ELECTRIC-VINTAGE-PIANO-KEYBOARD-MODEL-110-SUSTAIN-PEDAL-/190590494102

With the fall cover, music rack, sustain pedal (with instructions!), service manual.  Not sure if it has legs/power cord.  Local pickup only.  Anyone live out that way?  Wonder what it will go for.

Thought I would share a mod I made to my 200 after overhauling the amp.

R32 is the main resistor which sets the vibrato rate.  Normally the value is selected at the factory to set the rate around 5.75Hz.  Mine had an 18k resistor, at the low end of the range on the schematic.

I played around with some parts and found that for my amp, a 15k 1/2w resistor in series with a 25k linear taper pot worked pretty well as a rate control.  The adjustment range is not huge but definitely usable and musical.

One has to be careful selecting component values as the oscillator will stop working if there is too little or too much resistance at R32.

There was a little bit of thump at the slow end of the rate knob, which pretty much disappeared when I got around to replacing the three .12uF caps with new ones.  Tweaking the value of C39 a little might help solve this problem too.

After I was satisfied with my component arrangement, I soldered in two leads to where R32 was on the board, custom-made a bracket for the rate pot, and installed a 3-knob faceplate from Ken Rich Sounds, normally sold with their custom 200 amp and vibrato unit.  They were able to sell me the faceplate for the same price as a 2-knob version.  I had an extra 200-style knob laying around, so it looks very seamless.  Will try to put up photos of this at some point.

Also, R32 could also be replaced with a trimmer or internal pot, if you don't want to mod your case but still want to be able to control the vibrato rate, say for a specific recording, etc.

The whole mod cost less than $50, and most of that was for the new faceplate.  The speed range available is not as impressive as the Warneck VariVib or Vintage Vibe's new custom amp, but for the low cost and ease of installation, I think it is pretty good.

Hello, my first post!  I'm an EP/vintage keyboard enthusiast and tinkerer.  I have a day job as a machinist and technician for a science museum.

Recently I did some repair work on a 200 for a friend who is a touring artist, and he gave me a 700 he wasn't using in return. I'm somewhat familiar with the 120, but have never owned one.  I know it's not the most desirable model, but I hope to learn some things from working on it so I can build my skill set.

From what I can tell, this 700 could be a very early example.  The speaker is a Jensen P12R from late 1957.  The transformer codes are from Sept/Oct 1958 or so.  Several things about this piano differ from what I have seen in photos of other 700 models.

In particular, the volume knob is on the name rail, and the pilot lamp jewel and headphone jack are on the lower front panel below the bass end of the keyboard.  I think these are typically located on the bass side cheek block, correct?

I also noticed in the service manual, it mentions that the procedure for removing the top is slightly different in very early production examples - on my 700 the screws are underneath, behind the back panel.  The top is secured in front by means of angled cleats.

Supposedly these were made as early as 1959 (sometimes I see '58 mentioned), but has anyone ever encountered one of these with the features I mentioned above?  The finish on this piano is not in very good shape, and all of the damper felts are gone (they were replaced long ago by open-cell foam weatherstripping, which has fully disintegrated).  So it is not going to be a collector/museum piece, but I am still curious about the manufacture date.

Also, if anyone has a spare #19 Eb reed for the 120/700, I would love to buy one from you.  Vintage Vibe is currently out of stock on those.  I could also make do with a #18 D and just tune it sharp.