M-3 Bass Pedal Misbehavior

[David Anderson]

I'm looking at an M-3 where the lowest C pedal works normally, but all the pedals above it sound like a mixture of notes. I don't work on that many spinets, so I was hoping a spinet expert might chime in as to what specific problem with the mechanism I should be looking for. I last worked on this spinet in 2014, and it did not have this problem at that time. Since then, it has been moved twice.

[muckelroy]

Check that all wires are connected. If so, it's likely a mechanical problem with the pedal contacts.

There are two sets of contacts, a "pedal contact" and a "pedal keying contact". The "pedal contact" opens when a note is pressed, and "pedal keying contact" closes.

When you release the note, a latch holds the "pedal contact" open.

You probably have to drop the pedal keyboard down and inspect it. I can't recall the precise symptom which I had with my M2 pedal board, but I did have to replace a broken phenolic pedal pusher. They look like this:

[Jaim]

The bass pedal tone wheel pickups have a separate ground. Check the black wire which runs from the 2 resistors mounted on the terminal tab on the back of the TWG to the soft/normal tab.

Jim

[enor]

If everything above the lowest C sounds like 2 notes together, that means that either the C pedal contact sticks open, or there's a break in the wire going from the lowest pedal up to the generator.

This is a very common phenomenon if the organ is standing on a thick carpet.

[Sweet Pete]

Carpet is not a good choice for the surface an M3 sits on.Or any other spinet for that matter.
This happened to the M111 a few moves ago.Since then all spinets ride plywood to protect legs and pedals.
Stairs are a real PITA with a spinet compared to a console,the extra weight is WAY easier to handle than bad
ergonomics.
Stood the M111 on the treble end and had a good look.Got away with two anchors holding the genny....
There it was,a stuck return spring.something lodged.And.....the other two anchors of course.
Popped it back out and voila,fixed.
A few years back there was a garage band I sat in with that had an M3/147.We put plywood under it for this very reason
When played it would make loud non musical sounds,flat five can work....not usually together .....level flat smooth is preferred.
The pedals sound just fine,legato is sure nice.String bass add on's were modeled after it's 'decay'.
That went into the first M's and RT's.In '49 this was ground breaking tech! ;>)
Mounting the on/off to the expression pedal was so 1940's and really works too!

[David Anderson]

Thanks for the responses. The spinet is on a carpet, and I've passed the information on to the owner.