Treble Resonator

[Bill Ballard]

At 10:13 PM +0200 7/5/03, Richard Brekne wrote:
>Just recieved a shipment from Pianotek which included a Treble Resonator
>turnbuckle... and I was wondering if any of you have any experience with
>them and perhaps have a tip or two as for a most sucessfull
>installation.  The directions were marketing plugs then real
>directions... but I get the idea of what goes where.

On the other list, Chris S and Robert Grijalva (the inventor) were 
saying that on a B, you'd need a right-angle drill (the small 
cordless Makita), and that even for a D, your drill bit would have to 
be a 10" one. I'd guess there'd be nothing wrong with temporarily 
removing the bell and the wooden anchor block for the second 
hitch-pin web tie-down bolt, simply to swing them out of the way. One 
at a time, and re-attaching each as soon as you've drilled the holes 
they were obstructing. If you think that the web is going to bulge 
upwards immediately and disastrously, you can set a dial indicator 
(mag base on the plate, probe on the bridge) to monitor the 
situation. This will also tell where to return things to, should 
there be any actual motion.

>Just how is it this is supposed to improve the sound anyways... does
>putting tension between the belly rail and the rim somehow increase
>support for the crown in this area ??... or what ?

Robert's notes are pretty clear on what it does. In coupling the 
belly rail to the rim at that point, it is stiffening the structure, 
and lessening the chance that that part of the board perimeter will 
be and area where the board energy can be damped. Del and Ron were 
pretty clear last spring, that it shouldn't be expected to restore 
crown in that region. This is not a M&H tension resonator.

Robert says that when the treble bell was added in 1885, it was 
necessary to remove a rim beam, creating the weakness in the rim/rail 
system which Robert's turn-buckle coupler addresses. That would be 
literally every 6' and larger Steinway grand in the last 120 years. 
There is also a report from the field of one M whose treble sustain 
picked up noticeably when the turn-buckle applied tension.

I've bought one. I installed it first in a grey market Yamaha C7 
(which actually had the beam missing in Steinways), and moved it next 
to an 1892 Stwy B at a summer chamber music program. On my one day a 
week up there, the pianists are busy enough and I'm busy enough 
(covering two Saturday night concerts at two separate chamber music 
programs), that we haven't had the "miracle session". (The one where 
you start at neutral, crank in 1/8 turn, play & listen, and repeat 
steps 2 and 3, until everybody's light bulb goes one)

They played the first concert with 1/2" of tension, and the second in 
neutral, with no "Oh what did you do to our piano, please set it 
back". My jury is still out. But I'm sticking with Del's observation 
that nothing is going to put additional energy into the board after 
the hammer. All we can do is change the balance between loudness and 
sustain.

At 11:57 AM +0200 7/6/03, Richard Brekne wrote:
>Is that device in picture two next to the "bell" similiar to these 
>newer treble resonators sold by pianotech ?

I guess you haven't opened the box yet... <g>

Bill Ballard RPT
NH Chapter, P.T.G.

"No one builds the *perfect* piano, you can only remove the obstacles 
to that perfection during the building."
     ...........LaRoy Edwards, Yamaha International Corp
+++++++++++++++++++++