The only way to effectively get rid of these annoying longitudinal modes is to redesign the bass strings. The only maker I know who can do this is:

http://www.pianostrings.com/

I believe he has a way of tuning the longitudinal modes that effectively changes the pitch of the mode to something more pleasant.

Also, I forgot. As an Wapin installer, I can say authoritatively, that Wapin has no effect on the longitudinal modes.

Hi Michael,

James is the one who is working on the strings. He and Jim Ellis did the spectal analysis and James Arledge is going to tweak the windings.

I'm curious, have you actually measured a before and after on a piano with a prominant LM? Since the effective length can end at the bridge but doesn't always, it seems like it might have an effect. I suspect the phoenix system might have more though.

Todd

Todd,

I haven't paid much attention to the area of the piano you are talking about. I always felt like the bottom octave of the piano was the least of my concerns, rather I spent all my efforts trying to get better sound everywhere else. Do a search on Harold Conklin - Longitudinal Modes and you ought to come up with something. My own piano has some of these artifacts (it is a Wapin Baldwin C (6'3"). Every once and a while I think about replacing the strings to eliviate the problem. They were replaced and the scale redesigned by David Sanderson about 8 years ago. I think I could improve on it somewhat. It's just money right now and I'm working to get my kids through college. Ughhh.

Yeah, James Arledge is the way to go for the bass strings, which is where my problem is. But LM issues often crop up in the unwounds too. I have Jim Ellis's book and read a few of Harold Conklin's articles as well as some stuff done at MIT. A lot of it is tuner speak, but the physics is very cool.

I think you should measure to see if your design changes LM's in unwound strings because if it affects them it might me the only cure.

Todd

I have used Arledge almost exclusively since he started making bass strings (at least that I was aware of). He does good work. There have been a couple of rough patches, but for the most part I have been pleased. Arledge did the bass strings on my Steinway O, and they sound really good. Sometimes I fear that he will become too popular, and the quality will slide. It seems like alot of people use him now.

He supplies the strings to M&H now, so he's not a small scale shop.

I spoke to him about my piano and sent Jim Ellis's spectral analysis traces along with 2 strings.

I'll be interested to see if they can resolve the out of tune Longitudinal 13th partial.

I have notice the if Richard re-seats the string, the LM is gone for a few minutes. That was the first thing that made me wonder if a different bridge or an aggaff system might have an effect on LM's. In bass strings, it's a relatively ammenable problem, but not in unwounds. I figured Wapin might have a big selling point if their design had an effect. Sounds like a no go.

Is it gauche to ask approximately what it costs to do this install (parts and labor)? I have a 1918 M&H CCD (9') which was partially rebuilt about 15 years ago. I love it, but have been toying with installing new hammers, having action work done, etc. Don't think I need new strings, though, so the job would be as described by CC2. Thanks for the info

I had Arledge bass strings on my rebuilt M&H 1925 RBB, and for some unknown reason, they did not sound good....they had a thin, hollow sound, and none of the great bass that the BB is famous for. I don't know why the Arledge set did not do well...perhaps there was a mistake in the scaling for my BB, or some manufacturing glitch?

My re-builder did nothing but switch to Ari Isaacs's bass strings, per my request, http://www.isaacpiano.com/bass.htm and the transformation was incredible, night and day difference. The tone is now rich, full, and deep. with the appropriate bass growl that the BB is known for. As soon as I get this piano home from the re-builder, I will make some Zoom H4 recordings so everyone can hear what I am talking about.

First of all, the Wapin Co. does not dictate to it's installer what to charge. We all pay a license fee for each particular piano we convert. The cost of materials isn't much. The main cost is labor. So, I would imagine that the cost could vary quite a bit depending on who is doing the work, and what part of the country you are in. When doing an installation with the strings already off, or when recapping a bridge, it goes pretty quickly. When doing a retrofit job on a piano when the strings are not being replaced, I plan on several days. It doesn't always take that long. Some of the installers say that they can do a complete retrofit in a day (with two people). I believe them, but have never been able to do it that quickly. On Dan's piano, it took two of us three days. We did some extra work, replacing some of the rear pins as well. Some of the pins were extremely tough to get out. His bridges had been recapped recently, and the pins were really tight. We had to improvise. On an older piano, the pins usually pull out much more easily. So, it varies.

I usually qoute in the neighborhood of $2k. This includes converting the bridge, pulling it back up to pitch, leveling strings, and tuning. To travel to Mass., I would have to charge twice that to account for travel.

You would be better off finding somebody local. Tim Peng, RPT, is in Boston. He helped me do an installation at Interlochen last summer, and I'm sure he could do a good job for you. Tim was one of the "apprentices" there. He did a really nice job at anything we asked him to do. Tim was a North Bennett Street product, and I was really impressed how advanced he was for someone who just got out of school. He does very careful work. If you are in Massachusetts, I would call him.