Acoustic to Electric Piano Conversion

[Patrick Poulson]

Good day to you all: I have a customer who has a pretty but generic baby grand that is unfortunately completely worn out, and is interested in having it converted to being an electric piano by way of installing a electric keyboard and amplifier. If you have done this before, I would be grateful to hear about how you did this, and what keyboard you installed.

Thanks,

Patrick Poulson, RPT

[Ron Nossaman]

First, ask the owner how piano-like the finished thing needs to be.
Xylophone, Clavinova, or something more convincing? That'll narrow the
responses.
Ron N

[Joseph Garrett]

Patrick,

Yes, I have done that. In a Square Grand.<G> I used a Kawai 7? note keyboard, because the square grand was an 85 noter, that didn't have room for an 88 set of keys. It was not an easy job. Most keyboards have a built in amplifier, albeit somewhat puny. I took they original speakers and built small bass reflex speaker boxes that fit inside under the soundboard aimed at the slot where the hammers went through to hit the strings. The control panel was relocated to where the damper tray used to be. (btw, there were no strings on the sucker because the entire case was made out of sugar pine and was prone to bend under pressure. "cheek lift" in a major way. Hence the reason for the retrofit.<G>) The main key board was modified so that it could be slid out just like a regular grand action. That was held in place by screws through the key bed.

The pedals that came with the keyboard were mounted upside down and activated by a spring board off of the pedal rods. Since both came with only two pedals that worked quit well.

The cheek blocks and name board had the on/off switch and head phones in them. I made a long brass plunger type thing that allowed the on/off switch to be mounted to the back of the cheek block for easy service.

Bottom line: it took a lot of brainstorming and imagination to make it all work, but was really worth the time. (I was paid, btw.<G>) Customers were happy to have their "family hair loom" back.<G>

Since neither one played very well, it was a vast improvement for them.

Best,

Joe

-----Original Message-----
From: Patrick Poulson
Sent: Sep 23, 2015 2:56 PM
To: Pianotech Google
Subject: [pianotech] Acoustic to Electric Piano Conversion

Good day to you all: I have a customer who has a pretty but generic baby grand that is unfortunately completely worn out, and is interested in having it converted to being an electric piano by way of installing a electric keyboard and amplifier. If you have done this before, I would be grateful to hear about how you did this, and what keyboard you installed.

Thanks,

Patrick Poulson, RPT

Captain of the Tool Police
Squares R I
gpianoworks.com

[Patrick C. Poulson]

Thanks for the response, Joe. I think that I would just run a line out to a combo amp, something with enough range to handle the bass. I like the idea of using the existing pedals, if I can work up a way of having them acuate the keyboard pedals.

There's always something new in this biz!

Patrick C. Poulson
Registered Piano Technician
530-265-1983

[Joseph Garrett]

Patrick,

In my case, I have a full blown woodworking shop, so I can make/modify as I go. The project took a lot of measuring and such. One of the two biggies is overall width in relation to the overall cavity width. The other is the height from key bed to the under side of the stretcher/pinblock. Just so's ya know. A lot of the job was trying to make the square still look like a square. In your case it'd have to still look like a real grand, (until someone tried to play it w/o "turning it on" first.<G>

Best,

Joe

-----Original Message-----
From: "Patrick C. Poulson"
Sent: Sep 23, 2015 6:49 PM
To: pian...@googlegroups.com
Subject: Re: [pianotech] Acoustic to Electric Piano Conversion



[Joe DeFazio]

Patrick Poulson wrote:

Good day to you all: I have a customer who has a pretty but generic baby grand that is unfortunately completely worn out, and is interested in having it converted to being an electric piano by way of installing a electric keyboard and amplifier. If you have done this before, I would be grateful to hear about how you did this, and what keyboard you installed. 

HI Patrick,

I did it to two (ex-)pianos, though I did not install speakers and an amp (external sound components were already available).  Though I generally hate to see an instrument meet its demise, in the case of these pianos, it was practically unavoidable, for reasons I won't go into here.  

It's a lot of work, and not even remotely cheap if you get paid for your time (as you should).  You might be able do a pinblock, epoxy-wash the board, restring, and put on new hammers for not that much more (especially if they are going to spring for a good keyboard and sound system, which they should do).  I'd much rather see you twist their arm into going the keep-it-a-piano route.

But if you decide to forge ahead, here are some observations:

If you like solving problems creatively, it could be a good experience for you.  If not, walk away.  Joe G alluded to some of the problems; I concur with his assessment in general.  

The first, possibly biggest problem is that the height of a digital keyboard, from the bottom of the (presumably metal) case to the top of the naturals, is much greater than the height a real piano action from the bottom of the keyframe to the top of the naturals.  If you put it on the keybed, the keys will be too high, and the fallboard won't be even remotely close to useable.  My solution to that problem was to (carefully) cut out most of the front of the keybed.  I routed rabbets into the underside of the remainder of the keybed (the part that was mostly under the rim), into which I installed substantial steel plates which jutted out an inch or so into the newly vacated area that was the front of the keybed.  These two plates became a ledge that the bottom of the keyboard case could sit on.  So, the player's knees, if they were to lift them (or be tall), would bump against the bottom of the keyboard case.  I was able to work this out so that the digital keytops sat in almost exactly the same plane and front-back position as the former real piano keytops.  That allowed: 1) a normal amount of room for the player's knees 2) a practically normal looking keyslip area (the keyboard front resembled that area of a real piano enough that non-technician's didn't notice the difference) 3) use of the original fallboard.  I made matching holes in the steel ledge plates and the "wings" of the keyboard case bottom, and fabricated new wooden cheek blocks.  A knob with a 1/4-20 stud protruding was fed up from under the piano through the holes in the steel plates and keyboard case bottom and into a threaded insert in the new cheek blocks.  That locked the action firmly in place yet allowed easy access for removal of the keyboard (about like normal action removal). 

I took very few pictures during the process, unfortunately, but I attached one picture of the keyboard with its side removed (but before removing its soon-to-be-discarded plastic cheek block).  I used Yamah keyboards, P-90 series, because they are professional quality, durable, fairly easy to fix, and Yamaha is good about keeping parts around (why go through all of this trouble and then have an un-replaceable keyboard part render the whole thing into furniture?).  In this (bench) picture, you can see the bottom of the keyboard case, which later sat on the steel wings screwed into the bottom of the keybed remainder.

A second problem was relocating the inputs jacks for the pedals, audio outputs , MIDI ports, etc.  You might have to disassemble and reconfigure the keyboard's case in order to avoid interference with the fallboard and/or cheek blocks.  I chose the Yamaha model in part because on it, all of those connectors were clusted in the bass-side endcap.  I took off that endcap and mounted it to the back of the case.  That got it out of the way.  Here is a picture of some of the parts dissassembled (unfortunately).  The picture shows the rear side of the bass area of the disassembled keyboard case (if it were assembled, the backs of the sharps would be jutting up aginst the blue tape at the top of the picture, and the keys would be protruding out of the top of the picture).

As for the pedals, it was easy.  I built a box on the underside of the keyed terminating about where the pedal rods come up at the rear of the lyre.  I put a standard keyboard sustain pedal in the box, upside down (something like this: https://on-stage.com/products/view/ksp100), with the bottom of the pedal assembly against the bottom of the keybed.  I drilled a hole in the middle of the pedal so that the pedal rod (which had a pin protruding from the top) pushed up on and was captured by the pedal.  It was invisible unless you crawled underneath, and felt very normal to the player.  You could probably get by with one pedal in your circumstance, though doing two wouldn't be hard.

I had many other site-, piano- and keyboard-specific challenges, but I won't get into them here.  In the end, both pianos worked successfully, looked normal to a non-technician, and the pedals and fallboards worked fairly normally (though the fallboards didn't quite close against the keyslip, they came reasonably close).  In fact, more than one (non-classical) professional musician played a show on one of them without realizing that it wasn't an acoustic piano.  Although I've avoided similar propositions in the years since, in this case it had to be done, so I did it successfully.  I hope that your client's piano can be salvaged, but, if not, I hope that this helps.

Good luck with it,

Joe DeFazio

Pittsburgh