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Hello! I'm in the process of getting a Hohner Electra-Piano T to work properly for a customer. I thought I'd share some info on it here, also to get some suggestions perhaps; mainly on what materials to use for the dampers! Originally it looks like the reeds were dampened by some kind of clay pieces - or at least it has turned to clay.

Has anyone found a good replacement material for these dampers in terms of sound and durability?

The other thing that seems to need replacement is the little foam cushions that the hammer assemblies land on; these have become brittle.

Here are some pictures:









A lot of the damper blocks had already fallen off; I took all of them off except the lowest



The light brown foam piece that's brittle and squashed

Hi all,

A discerning customer just pointed me to this page detailing some interesting low noise mods for a Wurli 200A:

https://illdigger.wordpress.com/2016/07/03/wurlitzer-200a-piano-repair-and-low-noise-mod/

Have these been discussed here before? I couldn't find anything about it through searching. Also, has anyone tried these? Any opinions? Is there any more information available on which parts are required exactly, like the low-noise transistors?

Or perhaps the maker Johnny Illdigger would be available to offer some more info? Looking forward!

Hi all,

I'm restoring a Pianet N for a customer, and I could use some help on how to tackle the issue of it producing mainly a *lot* of noise and little tone - although there is some, faintly in the background.

The preamp is the version with the AC125 & AC107 germanium transistors, which I suspect might be the culprits... I've replaced all the capacitors already, to no avail.

The +400 volts indicated in the schematic is only 325 volts measured, perhaps this is an indication of a defective power transformer or bridge rectifier, and the reason for the low signal-to-noise ratio further down the line?

Can anyone tell me what the AC voltage at the transformer should be?

Any tips greatly appreciated!

Hi guys,

I'm optimizing a D6 for a friend and have hit a challenge with its overall frequency response; I usually work on Rhodes pianos so I could use some help with this.

The thing is that this clav has a significantly reduced high end, which has become apparent to me now that I have a second D6 next to it that sounds way brighter in comparison. They also differ in that the brighter one has the preamp board directly attached to the rocker switch panel; the darker one has the separate board screwed to the case floor.

Some time ago I did the upgrade mods to the darker one found here: http://clavinet.com/d6upgrade.htm - this was before I had noticed the overall darkness; I did test the sound difference after each individual mod and only heard (some) noise reduction, no drastic EQ changes.

Also I compared individual EQ bands between the dark & bright D6's I have here - it really does sound like there's an overall EQ difference, not related to the individual bands.

So before I launch into a more involved investigation of this particular preamp, does this issue ring a bell to anyone? Perhaps something typical like a transformer at the end of its life or something?

Thanks!

I was fitting an extra pair of line inputs to a 4-pin suitcase (using this really simple passive mixer schematic based on 10k resistors), which worked - but then disaster struck: during testing there was a short circuit on the power switch, which made the circuit breaker of my home wiring kick in.

The piece of foam that normally prevents the power switch contacts to touch the metal plate above it turned out to be missing... I hadn't noticed that. At the moment the amp isn't working, so I thought maybe someone here could give me some info before I take it to my buddy who is a proper electronics engineer but doesn't have special expertise on this amp.

Some observations:
- the pilot light still comes on;
- apart from some charring on the power switch contacts (on the inside the unit) there is no visible damage to any of the parts or wires;
- when I measure the voltage on the power module connectors, I get 24V and +/- 44V, the latter of which seems a bit high;
- the pre-amp outputs are still working, so the pre-amp is OK it seems.

Has anyone been in the same situation? Any pointers on how to approach/what to test would be greatly appreciated, thanks.