Author Topic: 1973 MK1 Suitcase 88 - Notes Dampen early / halfway through key release  (Read 165 times)

Offline spacecho

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Hello All,

I have a lovely 1973 Suitcase 88 (Hybrid Hammers).
It has had extensive work done over the years - miracle mod, VV backchecks, grommets, felts.

The piano sounds amazing, but there are a few issues i'd like to resolve:

An issue i have had with it is that the dampers come up early - when the key is only halfway through being released (to resting position)
This makes the piano feel choked as the notes dampen before my fingers have even left the keys.
My notes don't all dampen on / off cleanly either.

I compared this to a friends MK7 and found that on his modern rhodes, the note is dampened very cleanly within the last 1-2mm of the key being released to starting / rest position - much nicer.

On observing the bridle straps - i see that they look quite firm tight - no slack at all - don't know if they have been adjusted by the tech i bought the piano from many years ago.

Here are some details of the setup:

The bass side is shimmed with a melamine (3mm) strip, in addition to the 1mm black shims at each end.
Key dip is a smaller than normal (8mm or so)
Tone bars are at standard 3/8".

I'm wondering whether tight bridle straps would cause this condition / or is it loose straps that do this.
I suspect that my dampener arms might have lost tension also.
Not sure if the backchecks interact in any way also?
The rhodes had lots of key bounce before i put the backchecks in.
It is fairly heavy to play as well.

Hoping to make improvements to this wonderful instrument, and am looking forward to hearing your suggestions!

Thank you all!




Offline David Aubke

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Usually bridle straps have a very small amount of slack when the hammer is at rest. But an overly-tight bridle strap would only pull the damper arm further away from the tine. It wouldn't cause it to return prematurely.

Most likely, you just need to bend the damper arms a little bit. Try to bend them at the point where the bridle strap attaches. Pull them away from the tines. You're looking to strike a balance between the tine's freedom to vibrate and the felt's ability to stop it. It sounds like yours currently favors the felt too much.
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Offline David Aubke

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Tight bridle straps may contribute to key bounce as they'll retain energy better than a strap that's allowed to go slack at rest.
Unfortunately, I know of no way to adjust bridle straps. They can only be replaced.

Heavy action is a hallmark of hybrid-hammer pianos. Even with the Miracle Mod, that curved hammer cam provides a less pleasing feel at the keys than the angled cam of the later design. Least that's my view. Some folks do prefer it.
Dave Aubke
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Offline Ben Bove

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David's right on about the bridle straps.  When you told me they dampen prematurely, I immediately went to loose, slacking bridle straps at rest.  It's actually very common on those vintages.

A video of course would be great if possible, you can upload it to a site and link it here.  You can also experiment on a note that has the premature dampening - slightly bend the felt tip downwards (use two hands as not to create any bends beyond where the bridle strap connects to the damper arm).  By bending the felt downward, you'll allow the arm to raise up a little more and ultimately use up more of the bridle strap slack.
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Offline spacecho

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Thanks for the suggestions!

The bridle straps are definitely taught.

Having given it more thought, i suspect that the angle of the dampeners is wrong? I'll check that they hit the tines flat (by pressing the tine assembly down with the dampener up one by one).

Perhaps my dampeners are weak through too much adjustment over the years. I was thinking of trying to strengthen the end part of the dampener (after the bridle strap) by reinforcing it with something / or creasing that half.

I have 16 NOS dampener arms here, so perhaps i'll try and re do an octave and see if new dampeners help.

Will report back in a week or two when i get a full afternoon to work on the piano.

Thanks again!


Offline David Aubke

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Fatigued damper arms is not something I've ever seen.

To me it seems like you're overthinking things. Do you have any pictures of the situation?

Don't spend too much effort trying to get the felts to hit parallel to the tines. You certainly want more contact than just the leading edge but absolutely parallel is unnecessary.

It could very well be your arms are way out of whack. Several pianos that have come through my shop had arms that a previous owner had bent way out of shape trying to compensate for other structural problems. If you don't know what they're supposed to look like, you might not realize how bad they are.
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Offline Ben Bove

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If the bridle straps are taught, then behavior should be normal.  The only things I would start looking at is if the damper arms are bent at the base where they're screwed into the action rail.  I'd have to see a video at this point to see what's going on...

Does this only happen in the bass / bass-mid section?
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