Author Topic: Homemade electric piano (Seeking help regarding pickup wiring!)  (Read 2707 times)

Offline gotkovsky

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Re: Homemade electric piano (Seeking help regarding pickup wiring!)
« Reply #30 on: November 23, 2021, 02:09:36 PM »
Hello dear people of ep-forum,

I haven't had much time to work on the piano for a few months, which is a pity for me, but the nice thing about this is that I've had lots of occasions to play the piano as it is (without dampers), and I think I'm now able to tell precisely a few things that could be fixed-up before I can call it done.

First, I absolutely need to stiffen-up the feet or just remake them differently. Right now they are just too precarious, and as the piano is quite heavy, the keybed sags by a few millimeters. The sagging isn't a big problem per se as the actions can be regulated accordingly, but as the feet are not stiff enough, everytime I move it or just bump into the feet the sagging changes a little bit, and so does the regulation, and the pickups positioning… so I need to work on that.

The second problem is the bass section sound. There's just way too much overtones, it sounds like a village bell and it's hard to tell what's the fundamental of the note, no matter how I position the pickups in relation to the reeds. It basically makes the lowest octave unusable, so I'd like to fix that. A musician friend found the solution by telling me how he would love his Rhodes to have two outputs, one for the bass tines and one for the rest, so that he could use a bass amp in conjonction with a guitar amp in live situations.

I want to do that for my piano. One output for the first 15 reeds, and another for the rest of the reeds, with two separate volume knobs, so that I'll be able to record the piano and treat the two sections independently (and probably low-pass the bass section). I know I'll use this piano primarly in my studio, so it's okay if I don't have a single summing output. The bass section is really unusable as it is so I don't think I'll ever want to do that. And I even have a Roland JC-40 which has a stereo input anyway. Sean, if you read this, I found your great thread and your Rhodes pickup wiring modification, which was also an inspiration, so thanks for that!

I read the few pages I've saved on pickup wiring again, but I still can't wrap my head around how the pickups wiring really works… so I'm again asking for help on how to wire the whole thing in order to get the maximum output/noise ratio and consistent volume across the middle section. Consistency in volume between the bass section and the middle/treble section doesn't matter so much as I'd like to have to separate volume controls.

So if anyone has the time to help on this, give a few clues, or even better suggest a schematic, I'd be super grateful… here's an empty drawing of the wiring in case it helps:



Hope someone can help, and I'll continue to feed this thread as soon as I have the time to get back to the piano, which should be quite soon  :)

Cheers

Offline sean

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Re: Homemade electric piano (Seeking help regarding pickup wiring!)
« Reply #31 on: November 23, 2021, 03:46:51 PM »

Kevin,

Splitting the harp will not get rid of the overtones, it will only allow you to EQ them differently - that is your intent, right?  That might be a good last resort.

I think the overtones can be reduced by changing the impact location of the hammer tip against those longer tines.  On a Rhodes, we call that adjusting the strike line.  I suspect that your hammers are hitting the tines too close to the base (anchored end) of the tine.  You want to induce a swing of the tine, not a standing wave along the length of the tine.  Are you able to move the strike point until you find the sweet spot? 

You did show your friend my split mod instructions at https://ep-forum.com/smf/index.php?topic=4730.msg52770#msg52770 right?

Sean




Offline gotkovsky

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Re: Homemade electric piano (Seeking help regarding pickup wiring!)
« Reply #32 on: November 24, 2021, 01:42:00 AM »
Sean,

Thanks for your reply. Yes I showed your thread to my friend  :)

My goal by splitting the harp in two outputs is indeed to be able to eq them differently, sorry if this wasn’t clear in the first place.

I  tried everything to try to overcome the bass overtones problem at the source. Strike point, several hammer tip materials, solder pyramid shape, action regulation, etc. I also tried to remake a few reeds as close as possible to the shape of the Wurly’s, but that didn’t make any difference. Actually the undesired overtones of a specific bass note does not seem to change much between two reeds tuned to the same note, which is surprising. It might be related to the steel that I’m using for the reeds,  the harp design or more likely the geometrical inconsistency of my handmade reeds.

So that’s why I’d like to go with the two outputs solution, I don’t know if this will be the best solution, but I can always remake it differently if it appears to be less than ideal  ;)

Offline Whalerman

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Re: Homemade electric piano (Seeking help regarding pickup wiring!)
« Reply #33 on: November 30, 2021, 04:24:44 PM »
I can not speak from personal experience, as I've only wound, but not finished, my own pickups for a bass guitar - but my question is would it make sense for you to dip your pickups in wax or some other material?   I know that older pickups were done in wax - I think the idea was to prevent the wire from coming loose with all of the vibration and shock.   
I think you have built something you will always cherish.   My 100% congratulations to you on sticking with it.   Fantastic work.   And I know why you did it...   Because you were able to rationalize purchasing even MORE tools.......  :-)  :-)
- Paul