Looking for sage advice re: bass piano strings. I recently purchased a Schimmel 7' piano which had been idle since it was built (2004-5). The bass, especially at the cross-over, is "twangy". It sounds like a string problem to me, but there are no visible signs (loose windings, corrosion, etc). My technician wants to replace the hammers (they are hard and won't stay voiced) and if that doesn't solve the problem, replace the bass strings.

I am concerned that the problem may lie with the piano itself and therefore cannot be solved by throwing money at it. Any suggestions re: string replacement etc.? Anyone have similar experiences?

First thing that I do in a situation like that is try to get an idea of what the offending strings sound like without the influence of the hammer. Just lift the damper by depressing the key and pluck the string as close to the strike point as you can with a guitar pick - compare the tone with hammer blow and do not focus on the attack. If no twang then it is likely a hammer voicing issue.
The tech should try all of the simple things first: mating hammer to string, shaping the hammer, regulating, tuning - can the strings be tuned beatless? - be certain that damper felt is not touching the string.
A 5 year old Shimmel that has been idle should have some resiliance remaining in the hammers.

All of the above has been done and at first it seemed that the voicing was in fact the problem, but the hammers re-harden in a matter of days it it's difficult to remember how it sounded at first.

Any hammer suggestions? Piano Tech apparently has a new hammer made for them by Abel which is supposed to be excellent. Natural, untreated wool on a core which has a little more give. We were able to get a hold of one (a C 2octaves above middle C) and it seems good but with only one note, and a high one at that, it is hard to tell.

The original hammers should be completely workable.
I agree with Gene regarding the approach to this issue....
Voicing is a craft and a skill which requires dedication and application. Your tech might see these issues regularly i.e. hard european hammers etc but the techniques to get them resilient and workable can take time...shoulder needling especially can be a hard job if you don't do it often.
I've no doubt your tech is a splendid fellow...but you might ask him if he's done any classes with Schimmel/Renner/Abel at convention to learn these processes...hard to get it from a book or a mentor.

Hope that helps...

You received several responses on your other thread. You seem determined to get new hammers when several of us have suggested this is not necessary. A set of hammers frequently lasts 25+ years in home use.

I believe your problem stems from incorrect regulation and/or voicing. Twangy sounds in the bass are often associated with hammers not hitting both bichords at the same instant. Also the alignment of the hammers under the strings is extremely important. As far as not holding a voicing...that would lead me to believe that the tech isn't really doing a "deep" (i.e. deep down into the shoulders of the hammer) voicing. Unless you've exhausted all your other options I wouldn't even think of replacing the hammers on a piano that has had so little use. Perhaps another technician (one who comes recommended by Yamaha or Steinway) might be in order.