[pianotech] Board: trash or keep protocol

[David Andersen]

Thanks for the clarifying challenge. "if necessary" in this case  
simply means if it doesn't pass the pluck test, nothing else IS  
necessary. Of course if it passes, you measure crown and bearing.  
Sorry to be unclear.

Totally agree with smackin' the piano hard, fff, in all sections, to  
detect what you call attack distortion (I've always called it  
distortion or overdrive.) Always a part of my full evaluation...
Better?
DA


On Apr 6, 2009, at 8:38 PM, Ron Nossaman wrote:

> David Andersen wrote:
>> 1. Pluck strings in all sections of the piano; listen to bloom and  
>> sustain appropriate to each section. If it sounds good---if there's  
>> a definite increase in sound pressure and amplitude, a "bloom,"  
>> within a second or so of the pluck in the tenor and treble (it  
>> takes longer after the pluck for the bloom to appear lower down in  
>> the piano) and then almost a coupling or strengthening of the  
>> fundamental tone and the first two partials as the tone decays---it  
>> is good. If not, and if there's any question or less than strong  
>> feeling, we replace the board.
>> 2. Measure bearing across bridges (if necessary.)
>> 3. Determine crown through the various methods talked about here ad  
>> infinitum (if necessary.)
>> The ears (and the bod they're attached to) are the first and the  
>> final arbiters of everything to do with pianos.
>> DA
>
> Disagree big time. Both crown and bearing will tell you something  
> about whether what you are hearing today is likely to still be there  
> tomorrow, or next year, so that's first. Second is the sound, and  
> that needs to be assessed at high attack levels as well as plucking  
> and blooming, particularly in the killer octave. Listen for the  
> Bwwaaarrgggghhhhh attack distortion, and know that it will only get  
> worse. Putting a rebuild on top of a wonderful sounding (at pluck  
> volume levels) board that is on the ragged edge of crapping out  
> structurally isn't something you want to figure out after the fact  
> when you get *the call* next year. If it passes the structure test,  
> *then* if it passes the sound test, *then* it's a go for keeping the  
> board.
>
> Ron N
>