Piano World Home Page Forums Our Most Popular Forums Piano Forum Why is long sustain a good thing?

As I've said before, it's less the counting of seconds in sustain than it's about the decay rate right after the attack. Sustain doesn't help you when the particular note goes 'Poooof' right after the attack.

We?

Does a piano even have a sustain phase to the sound? I thought it was essentially sharp attack followed by decay until the dampers come in.

It would probably be more meaningful to talk about how long a piano note takes to decay to say 50% of perceived loudness so we all know what we are talking about.

Yes, I talked about "useful sustain" on around three posts on this thread already which is I guess the same thing you are saying. But that seems quite different from what you said in the part I quoted. So can I assume you mean that a long sustain a barely audible levels with a fast decay rate after the attack is not useful/relevant or a good way to measure sustain but a good useful sustain(which I think you mean by a not too fast decay rate) is important?

I think much of the confusion/debate on this thread is because people are using "sustain" to mean different things. Some posters want to use it to mean the time it takes for a note to completely die out. I and some others think that's meaningless because only the useful portion of the sustain is relevant. When a note is just barely audible it will be of no practical use in contributing towards a melodic line and will also be totally drowned out by any other notes played after it.

So yes, I agree that the quality of the sustain should be evaluated by how long it takes to decay to some level of loudness relative to the initial sound. I don't know if it's a good idea to try to put a percentage figure on that level or what a good percentage figure would be. I basically just use my ears and make a judgement. For example, in the recently posted example there was at least one note that clearly had very poor)almost zero) sustain. How good the sustain was on the other notes would be more a matter of judgement but their sustain was clearly better than the note with very poor sustain.

I have been moving my rebuilding shop this week, so I am a bit late to the game.

From my vantage point, I think that Keith is showing the fullest understanding of what is happening, and sees the complexity of a note first sounding to the point where it dies out completely. Too many posters see sustain as a singular event. This is oversimplified. Keith also bridges the technical to their place in giving value in the act of making music.

If we are going to most fully grasp what is going on in this very complex system, we must isolate the soundboard from the hammers, as well as listen to the piano as an integrated system.

The part that we identify as the attack I speak of as the onset tone and also as a saturation burst of partials. Almost always, we can identify the attack as distinct from the following sustain event. The onset tone can come from nothing to fullest volume very quickly or more slowly. How loud it will get can vary. The onset tone can have a shape that is more or less distinct, and having a longer or shorter duration. It can be a beautiful distinct pearl, or something more rounded and amorphous.

I use the term saturation burst because I see the attack phase as being a chaos of disorganized partials that eventually settle into what we think of as harmonic organization. In this process, the tone comes to fullest volume. Does it stay there as it settles into the sustain event, or does it lose volume? How quickly does this harmonic organization take place? Does it regain volume after the transition? We begin with a finite amount of energy coming from the hammers. We spend energy during the attack phase that is no longer available as we transition into the sustain. Is there a way to achieve more consistency and efficiency in the attack phase?
As Keith has suggested, we want the volume not to diminish as it transitions into the sustain phase. Ideally, this will also be a seamless transition.

Here is my list of ideal want to haves in the sustain phase: The note stays at full volume as long as possible wherein the volume gradually fades to nothing. The line is felt as a steady pulse of energy. The note has settled into an orderly harmonic structure that lingers through the duration, and this consistency remains as one steps up and down in loudness. Pitch is highly accurate and does not vary throughout the duration. I believe that all of these things are of musical value.

How much control do the rebuilder, technician and tuner have over these events?

How long is a piece of string? Imagine there is some obstruction or foreign object contacting the soundboard and therefore causing the sound to decay quickly ( or to have little sustain for those of us who are uncomfortable describing sound envelopes in the standard attack/decay/sustain/release terminology) . Just removing said foreign object would then have a huge impact on the sound decay rate giving a much longer sound and more musicality, on the other hand if the piano is already performing to its design there is unlikely to be any improvement possible without significant rebuild/redesign.

Yes, gwing, I agree about the foreign bodies and other such things that affect the sound of a piano.

My question was how much variation a rebuilder, technician or tuner can bring to the attack and ensuing sound when the instrument is already up to scratch. Although you say none, I had Keith Kerman's comment earlier in this thread in mind. I hope he and others can go one better.

My reasoning was about the character of the envelope. if the sustain decay is long then the sustain swell is also longer.

-chris

A sufficiently skilled rebuilder and technician can radically alter the attack and decay depending on your budget and their skill and experience.

A lot of what I am about to describe do not come from common skill sets.

A technician can dramatically alter the attack with voicing of the hammer. The hammer can be made softer for a ( surprise...wait for it ) softer attack. The hammer can be made harder for a more percussive attack. The hammer's shape can be changed which also changes the attack. It can be made pointier. It can be made rounder.

The hammer can be lightened. The hammer can be made heavier. Depending on how much you do, the sound can be altered in a subtle or more obvious manner.

The strike point can be changed. This is the where the hammer actually strikes the string. It can be moved further in or further out.

The density of the hammer can be changed in different areas. The shoulders of the hammer can be hardened or softened. Same with the crown.

The hammers themselves can be changed.

The regulation itself changes the sound. And more importantly the perception of the sound.

All of these approaches will change the attack and subsequent decay and balance of fundamental to partials for better or for worse.

PianoCraft may actually voice the soundboard. This is more common with string instruments, which is where we got the idea. We may strategically take a bit of material off the sound board if we think the soundboard itself is too stiff in that area or too impeded. We may stiffen the board up if we think it is too flexible. We may add weight if we think it will help. These approaches are extremely uncommon and not taught. This is all after the piano itself is completely together.

When rebuilding a piano with a new belly system you have endless options to affect the rate of decay. Every choice you make affects it. Type of soundboard wood. Type of rib material. Shape and placement of ribs. Bridge material. Bridge height. I could go on and on. Everything does something.

There are lots of basics that affect the rate of decay as well and of course this is always the starting point. How is the connection between the strings and the bridge? Are the strings level? Is the hammer fitted to the strings? Is the regulation good. Is the tuning good.

The tuning itself affects the decay/sustain. One can alter the tuning depending on the goal. There are tuners who strongly believe that a "dirty" tuning with one unison slightly out creates a kind of phasing effect that makes for a kind of re energizing of the struck note within the decay.

Everything has a small or large effect.

Don't get me started on room acoustics!

However, if the design of the piano is the primary reason for a fast decay or a big drop off in sound after the attack, without major surgery, you are probably only going to be able to improve it slightly and/or camouflage the problem.

YMMV!!!

PL.

It's somewhat valuable in evaluating the integrity of the belly.

Great post Keith.

A good voicer can also increase or decrease the time that the hammer is in contact with the string. This creates greater or lesser deflection of the string.

Thank you Keith, one, two, three better ... here again is the result:

As a musician I am very happy with about 3-4 seconds of "good" sustain in the melody section. I feel it is ideal when the note holds (hangs) at the level I played it at for a couple of seconds, and then slowly begins to decay. I can play a beautiful melody with a piano that sings like this. Less than this and I feel disappointed, more than this and I would not know what to do with it.

When I rebuild a piano I do my best to achieve this kind of result. Often I can...but not always.

Peter Grey Piano Doctor

This is the correct and realistic way to think about sustain IMO. The OP's idea of why 10 second sustain is not inferior to 20 second sustain made no sense because even 10 seconds of good or usable sustain is completely unrealistic.

Surely a good usable sustain is when the attack decays gradually and as long as possible. I think one can aim for 15 to 18 seconds in the upper treble of gradual decay .What is unpleasant even in such a long decay is if the sound suddenly collapses. ( I am not sure if I am counting my seconds correctly either )

Well perhaps he does !

a good sustain provides an unconscious imitation of sounding violin instruments on a piano. The piano is a percussion musical instrument, and the sustain provides its indirect affinity with sounding violin and a viola, I think.

Sorry, but your figures are just completely wrong. Just listen to your piano or to any piano. Play a single note without pedal.

Even if you measure the time to complete silence(which is MUCH longer than any useful sustain) it will not be anywhere near 15-18 seconds in the upper treble, say around the 6th octave. And, in the higest treble, there are not even any dampers because the sustain is so short they are not needed. What you described is more like the time to complete silence(again much longer than any usable sustain)in the bass.