Duplex muting

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Openwood
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Duplex muting

Post by Openwood »

A while back I was asking about ways of getting rid of nasty zings on the first few notes of the capo bar of a Yam C7. I had a Steinway-trained tech come and look at it and he basically put felt around the front duplex strings of notes 51-56 (B-E) which has helped. A few people here have pointed-out that note 51 in where the agraffes stop and the capo bar starts on a C7 and that it is farly common for the tone of these notes to be unsatisfactory.

Interestingly, I was playing my Yam C3 yesterday and noticed a really nasty zing/harmonic on note 55 (Eb). I checked that the noise wasn't coming from outside the piano and then tried muting each of the three front duplex strings in turn to see which one was the culprit. It was immediately clear that the first string was generating the unpleasant noise. I muted it by the very low-tech method of cutting a piece off an eraser and wedging it between the frame and the string; it does the job (well, to the extent that the string isn't vibrating anymore).

It was only when I'd finished my eraser trick that I noticed that note 55 is exactly where the agraffes stop and the capo bar starts on a C3!

If these notes are rubbish why don't they do something about it!!???
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chrisvenables
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Re: Duplex muting

Post by chrisvenables »

You're absolutely right - as I suggested to you in an earlier thread regarding the zing sound on your C7 at school.

Steinway invented the duplex system over 100 years ago and it's been a pain for technicians and for pianists with such a discerning ear as yours ever since. Whereas mother nature has no problem in the seamless transition from night to day, unfortunately piano makers have a massive problem in the transition from mid-range to treble, where top harmonics are vital to produce that ingredient X which separates the men from the boys. Yes, I suppose they could design the capo so that it had a more gradual changeover, (as, for example, Yamaha do with their final damper only damping 2 strings instead of 3 in the top treble) but it would be such a cumbersome job in frame design and so few people would appreciate it, that I guess they don't consider it worth the additional expense.

Easier and cheaper for the manufacturer to get the customer to pay a technician to do it on site for a few pounds,as you may very well do in due course. That's big business for you!

Most top concert artists are aware of it, along with plenty of other snags in such a complex piece of aparatus, and they just adapt to the vagaries of the instrument on which they are performing.
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Openwood
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Re: Duplex muting

Post by Openwood »

You're absolutely right - as I suggested to you in an earlier thread regarding the zing sound on your C7 at school.
Curses, I was hoping to get the credit for that idea and I would have gotten away with it if it weren't for you pesky kids :wink:
Steinway invented the duplex system over 100 years ago and it's been a pain for technicians and for pianists with such a discerning ear as yours ever since.
Why, Mr D'Arcy, methinks you are too kind (girlish giggle and much fluttering of a fan) - a simple country girl such as I can only blush at such a compliment, however unearned from a fine gentleman as yourself. But yawr fookin' right luv, me ear is fookin great, innit.

:shock: OOOH, but I have had a nasty thought. I've just moved into a new place with central heating and the piano is in a big open plan lounge/kitchen area. These couldn't be the first signs of an environment that's too dry, could they??? :shock:
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Re: Duplex muting

Post by chrisvenables »

Openwood wrote:


But yawr fookin' right luv, me ear is fookin great, innit.
Your ear may be great, it's just a shame about the rest of your body.
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Re: Duplex muting

Post by joseph »

Don't listen to him openwood, I'm sure it's a great body.. . .

Yeah that Duplex thing is a pain in the neck, and when the piano goes out of tune it whines. Bluthner don't have it, but then, they aren't so good at filling the hall.

The thing about pianos is, much as we love them, they are inadequate. The sound dies as soon as it begins, so you can't manipulate the note as other instrumentalists and singers can. They are never really in tune, and to my ears, even after they have been tuned they start to slip, they improve with age and just at the point you learn to love your piano, it's needing rebuilt ;-).

Can someone tell me, I know that soundboards wear out, but some techs and tuners have told me that for a while, they improve with age and a piano that is 10 years old, providing it has been well serviced, is better than a new one. I haven't found a 10 year old piano that has been particularly well serviced right enough,,,,, there seems to be a lack of good technician in this area.
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Re: Duplex muting

Post by chrisvenables »

The piano is King!

Re the sound dying - you should be able to get up to 45 secs of sustain, dying admittedly, but it's what nature intended. I agree about note manipulation, but singers can't hold a note for ever, nor most other instruments except violin and organ. Don't composers for piano 'arrange' their music with those inadequacies in mind? (Arps, trills and other such 'fill ins')

Re Tuning - I agree, it drives me mad, but as any tuned piano scale is a compromise anyway (equal temperament and all that) it's never in tune to start with. A concert pianist once told me he just 'shuts out' the phasing of bad notes otherwise he'd never enjoy the performance and 99% of the audience aren't aware of small amounts of string slip anyway.

Re soundboards - hammer heads influence the tone more than soundboard movement/maturity. I'm not a believer in getting bogged down in science but I believe the 'maturity' to which you refer is something to do with what 'they' call wood 'creep.' Studies on the tonewood in violins subjected to large humidity fluctation show that certain expansion and contraction improve the sensitivity and amplification of the string. However, on a piano with a massive loadbearing, I think it's safer to keep the piano soundboard in the state in which it left the factory. So yes, there is a slight improvement to the soundboard in the short term, but the long term trend is for a steady deterioration.
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Re: Duplex muting

Post by joseph »

Well I know that it would be rare to hold a note for 45 seconds! I agree that the piano is king, and we love its inadequacies. Schumann wrote as if these inadequacies didn't exist, and his pianos had far inferior sustain to what our pianos have today, although oddly these old fortepianos can have a more dramatic sound even if they don't sing as well.

I thought that was the case with soundboards. I know of the odd rare piano that is 70 years old or so, and has a beautiful sustained and singing tone, with the original board. However these are the exception and usually old pianos sound tired out.

I know some rebuilders replace the soundboards, and I have played some very nice pianos with replaced boards - particularly the ones in Steinways that have been rebuilt by Steinway. Mind you, they cost almost as much as a new Steinway.

Generally I prefer new pianos, and I guess thats the reason why. Even old pianos that have been restrung can still sound naff.
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Re: Duplex muting

Post by Barrie Heaton »

Duplex is not the problem, its the capo scaling which tend to be a pain if the piano (no matter the make) has been played hard. Then restringing the top improves the piano no end, as the string do get tired. This shows up in the capo area first S&S quite often restring the top after 2 years on model Ds in the concert stock for this reason.



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chrisvenables
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Re: Duplex muting

Post by chrisvenables »

joseph wrote:
Generally I prefer new pianos, and I guess thats the reason why. Even old pianos that have been restrung can still sound naff.
Joseph, I like you. Your ears aren't so bad after all..
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Re: Duplex muting

Post by joseph »

:D gee thanks! Openwood will get jealous though :wink:

My ears aren't so bad, although they are prone to infection. Must be the snotty kids and that RANCID collection of pianos we have at school.

Still, at least they are looking into the false economy of buying a Yamaha grand from the early 70s, when the designs weren't so good and half of its musical life has been used up. It will be slightly better than the old Bluthner that has been restrung but has cracks in the soundboard the size of the grand canyon, and a patent action that has never been regulated.
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Re: Duplex muting

Post by Openwood »

Well, I'm steaming at the ears about this problem yet again. The tech I got to look at the nasty tone on these notes put a small strip of felt under the middle of each set of three strings (i.e. one strip per note) in front of the capo bar (is that the CAPO SCALE rather than the DUPLEX SCALE? Maybe I have got my scales mixed-up here?) Anyway, it's definitely the strings nearest the capo bar at the keyboard end of the mother. The piece of felt presumably dampens the middle of the three strings only? It spreads out on either side underneath the middle string so maybe it effects the other two strings too? God, I don't know.

Anyway, it sorts out the problem at quieter volumes but one of my pieces is the Bach Chromatic Fantasia in D minor which ends with a fortissimo trill on C-sharp to D-natural above middle C; the two worst sounding notes! I just HATE the metallic background to these two notes more than I can say :evil:

Is there some kind of rubber tool (vicar) or heavy duty concrete that I can get to completely mute these capo/duplex/whatever the hell they're called strings? I just want them out of my life, I don't care if the resulting sound is dull; f*ck it.
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Re: Duplex muting

Post by Openwood »

I've been looking online at how I can mute these capo scale strings (or duplex scale strings - whatever the set nearest the keyboard end is called; I've got completely confused over the terminology). Bearing in mind that the notes I want to mute are: the B above middle-C and the neighbouring, C, C-sharp, D and D sharp, and obviously there are three strings to each note, what do you guys reckon is the best way for an amateur bonehead like me to do it? I've looked at felt wedges, rubber wedges and a rubber gang wedge. Apologies if this is making all you pros out there wince at the sheer stupidity of my question. It's just that I've tried explaining the problem to tuners until I'm blue in the face and finally it's come down to two options:

Option 1) Try and sort it out one last time
Option 2) Destroy the piano
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Re: Duplex muting

Post by mindbender »

Whether it's duplex or capo isn't the point, although it's capo at the front. Lots of pianists become irritated by sounds others don't hear - I can't believe, after reading previous posts from you that none of these technicians can cure it. All pianos with capo bars do it. Speak to your tech, not to the forum.
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Re: Duplex muting

Post by Openwood »

Mindbender: It's nice you can't believe none of the techs I've tried have been able to fix it; good for you. Maybe you'd like to have a go? It could be like excalibur - all the techs in England can have a go until someone manages to do the thing I've asked and paid them to do.
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Re: Duplex muting

Post by chrisvenables »

I really do sympathise with your dilemma and it's a tricky one, as I have only what you have said in your posts to go on. It's safer for me not to respond to your question, and I am leaving myself open to serious abuse in what I am about to suggest, but I do want to help if I can, albeit from a remote position which makes it even more than tricky.

I've had many customers who hear things on their pianos which I don't hear and, to be frank, in the end, rather than 'humour' the customer by saying 'yes there's something not right but I don't know what,' (what tuners call 'tuning the customer, not the piano') I just have to say what I feel, ie ' Sorry I don't think there's anything wrong with your piano.' Have other pianists noticed the same zing that you hear? When your technicians have attempted to cure the zing, have they made any comments to you? If you've paid them to identify and fix a problem and they haven't, then get then to come back and fix it for good. You say you experience similar problems on your C3 at home - The capo does produce some nasty harmonics when played ff at times. My recommendation would be firstly play some other pianos with the capo bar sytem, (eg Steinways) EXACTLY as you play your C3 and C7 for a substantial time and be as critical as you can be. You will probably hear the same zing. You MAY find it is commonplace. It is highly unusual for a Yamaha C series to have a real fault in its tonal quality - for TWO Yamahas in one small location to have the same fault is extraordinary. Often, on a large grand and a powerful one such as a C7, the pianist hears imperfections which the audience doesn't. - Just a thought- please don't take it personally.
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Openwood
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Re: Duplex muting

Post by Openwood »

It is highly unusual for a Yamaha C series to have a real fault in its tonal quality - for TWO Yamahas in one small location to have the same fault is extraordinary. Often, on a large grand and a powerful one such as a C7, the pianist hears imperfections which the audience doesn't. - Just a thought- please don't take it personally.
Fair point! I think the C3 may be just a tuning/voicing issue - I used a DIY rubber wedge on the first capo string just to shut the bloody thing up and I'm sure it can be fixed when I next get a tech across. The C7 is more of a headache because other people have noticed it too. I think muting the capo scale around those notes may be the least worst option in the long run. I'll ask for this to take place at the next tuning visit. And then I will leave this obsession alone for the rest of eternity! I do accept that I must sound like a nutter over this issue, but I do like to have everything 'just so'!
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Re: Duplex muting

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that zing problem is well known and very common in Steinway grand pianos. Barie mentioned that Steinway restrings the top of 2 years old pianos quite often. Do they? I have never heard about that. I am in doubt that the strings are the culprits, I believe it´s the hammer and therefore a voicing problem. A collegue of mine had a Steinway seminar for a few days and after that seminar a Steinway technician came in his area to maintain a S&S grand, so my collegue asked if he could watch him working. He could. He told me that this zing can be voiced away. No idea if this is allways the case or if it was true only for that particular grand. Anyway, I think it´s a challenge to get that voiced away. I guess one needs a very special voicing technique for that. Or, better said, a special knowledge as to where to needle the hammer. To be honest: I don´t feel competent enough to do that. That´s why I mute the strings with felt, too :cry:

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Re: Duplex muting

Post by chrisvenables »

Gregor wrote:that zing problem is well known and very common in Steinway grand pianos. Barie mentioned that Steinway restrings the top of 2 years old pianos quite often. Do they? I have never heard about that. I am in doubt that the strings are the culprits, I believe it´s the hammer and therefore a voicing problem. A collegue of mine had a Steinway seminar for a few days and after that seminar a Steinway technician came in his area to maintain a S&S grand, so my collegue asked if he could watch him working. He could. He told me that this zing can be voiced away. No idea if this is allways the case or if it was true only for that particular grand. Anyway, I think it´s a challenge to get that voiced away. I guess one needs a very special voicing technique for that. Or, better said, a special knowledge as to where to needle the hammer. To be honest: I don´t feel competent enough to do that. That´s why I mute the strings with felt, too :cry:

Gregor
How long before a restring of the top two sections can depend on how many times the piano has been tuned, as more tuning increases the chance of string breakage and grooving on the underside of the capo bar. And concert pianos can get a lot of tuning! It is the length of string between the tuning pin and the capo bar which creates the harmonic, which sometimes produces the 'zing' Softening or toning the hammers reduces the zing to an acceptable level, whereas muting that string section with felt or a wedge or super glue kills the harmonic completely and, usually kills the tone. I would agree with you that you should only voice a hammer if you know exactly which spot(s) to attack.
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Re: Duplex muting

Post by Openwood »

whereas muting that string section with felt or a wedge or super glue kills the harmonic completely and, usually kills the tone.
I think I read on the forum earlier that Bluthners don't have duplex scaling - I used to play a 2005 Bluthner Model 4 which I disliked intensely all for all sorts of reasons, but I wouldn't have said the tone was dull (certainly not bright, granted, but not dull either). How come they manage without duplex?

I'll ask for the strings on the C7 to be muted with felt rather than super-glue; the glue option sounds irreversible! I'd like to leave the piano so that someone with different tastes could have it sounding as they wanted.
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Re: Duplex muting

Post by chrisvenables »

Openwood wrote:
I think I read on the forum earlier that Bluthners don't have duplex scaling - I used to play a 2005 Bluthner Model 4 which I disliked intensely all for all sorts of reasons, but I wouldn't have said the tone was dull (certainly not bright, granted, but not dull either). How come they manage without duplex?
In a way, you answered the question within your question - (you disliked it intensely) They use the aliquot system where a 4th string is suspended above the trichords which vibrates in sympathy with the sound of the strings being struck. It can produce a very sweet sound. In addition, and most manufacturers who don't have duplex or aliquot simply leave the section of the treble strings between the tuning pin and capo (if they have one) and the area between the wooden bridge and the hitch pin unfelted. In other words they have an 'unscaled' duplex. (more crude)

It's a bit chicken and egg, but pianos with capo bars and duplex are designed to sound as lively and bright in the sections before reaching the capo bar, so muting of the capo would unbalance the tone. Your tech could try just muting 2 of the 3 strings, so you still have some harmonic, but I believe careful toning is the best method.
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Re: Duplex muting

Post by Openwood »

Closure is a great thing! I bought the new Stephen Hough in Recital CD this week and the Steinway he uses zings away like a pig on crack from start to finish. It's mostly the second D above middle C that sticks out but generally the whole tritone from the B-natural upwards has that metallic edge. I'm reassured from this and also from the comments here that I've somehow 'homed-in' on a sound the piano makes naturally and allowed it to drive me up the wall.

In other words the piano's fine but my OCD is off the scale :piano;

But you knew that already 8)
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Re: Duplex muting

Post by Gill the Piano »

Openwood wrote: the piano's fine but my OCD is off the scale
If you're up at 4:13 worrying about it, you need help, poppet... :shock: :D
I play for my own amazement... :piano;
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Re: Duplex muting

Post by Openwood »

If you're up at 4:13 worrying about it, you need help, poppet...
Oh, where to start, Gill; where to start... 8)
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