<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> </head> <body bgcolor="#ffffff" text="#000000"> Hi Christopher Putting a 7 foot Seiler in the context of your first post, along with your comments about Steinway instruments, I have to wonder if a less talked about (on this list at any rate) form of falsness is more accurately the diagnosis you should be after rather then horizontal frequencies. Tho to be sure I dont see the problem to be limited to S&S A-M's.... or Steinways and Seilers in general for that matter. First, problems relating to horizontal modes are nearly exclusively related to the lower region of the piano and as Bernhard pointed out they have to do with a near coincidence of the lowest horizontal partial(s) with very high transverse.  More rare is when a horizontal nearly coincides with a soundboard resonanant frequency. I'm not sure I'd describe either as a <blockquote>"shimmery sound about 4 octaves above the fundamental and it "appears" shortly after attack"  that  "decays along with the rest of the sound." </blockquote> tho. That description to my mind better fits a string that has either some kind of string noise present such as can occur from the speaking length front of the agraffes / capo when either of these are not functioning as they were designed to, or a string that has a falseness not characterized by the classic consistant period false beat. This falseness is often a wavery phase like with no distinct period, can either occur immediately at the attack moment or become apparent in the first bit afterwards and is very unsteady.  Careful string mating and voicing may help if indeed the problem is phasing that is impact induced but otherwise you wont get rid of the sound completely unless you increase stability at the terminations. I'm less then convinced we really know the mechanisms behind this falseness and the more talked about classic false beat, but I believe them to be closely related and have primarily to do with the bridge/bridge pin compound clamp termination / support and may even include the soundboard area immediately adjacent to the bridge at the affected area.  Ultimately, it is the soundboard that produces the airborn wave lengths that we hear, and therefore any out of phase behavior between the strings input at the bridge and this output sound will have high potential to create falseness, be they false beats with a distinct period, or this kind of unsteady shaky shimmering I am prompted to think of reading your description.  The only thing I know of that seems to have a positive affect on this are various schemes that essentially increase the massiness of the wood at the bridge pin. This can include the construction of the bridge itself, or the addition of stiffeners underneath or the addition of either CA or epoxy to the bridge pin holes. The cleanest and most precisely defined possible termination for the string also is a big plus in this regard. Bending the string around the bridge pin, as is often recommended has the opposite affect as it simply weakens the bridgepin / bridge compound support and introduces the potential for any small part of this compound termination to become springy in character. At some point that springyness will result in some form of falseness. The same can be said (and often is) for any aggressive string seating procedures. Much of this has been discussed back and forth many times through the last 100 or so years, and the persistence of widely varied opinion underscores our lack of a real understanding on the subject.  We do know however that a few things seem to have a positive long lasting affect. So while a deeper understanding may be desirable, it is not strictly speaking needed to effect significant improvements. Cheers Richard Brekne <blockquote> Hello list,     Many thanks to Berhard, Ron, Richard, and David-- all great suggestions and diagnostic routines.  I'll likely do very careful tests as the piano is a >10 year pristine 7' Seiler and I got in  quite deep with this person a few years back (acoustically isolating  the action rails.. it worked but neither of us were terribly  satisfied with the experience).   Also the sound is at the very edge  of my perception what with age and all.   Great things to try where  as before I had none.     On the vein: ever since the first reading on longitudinal waves in  the PTG journal several years back,  I've wondered if there are,  occasionally,  rather pronounced problems in S&S models M through A   in the octave below mC.  These unwelcome sounds have been more  distinguishable and in the same four 8va above fundamental range.   I've always wondered why the owner/players have not complained...   I've never pointed it out to same.  Comments? Christopher Glattly </blockquote> </body> </html>