What is “warmth” and how do you get it?

Hi guys - great posts. @Kijanki - thanks for the jitter discussion. And yes, timbres of instruments are extremely complex. It makes for fascinating reading; the book I mentioned before is a great place to start - non-musicians would have no problem with any of the terminology, from what I remember of it.

@Kirkus - thanks for the great post! I had a girlfriend in college who was doing alot of composing in the electronic music studio, and was actually quite frustrated by the bewildering array of options. It was a very overwhelming experience for her. To be honest, I'm really not very enthusiastic about any form of electronic music - while I appreciate it, I just don't care for the timbres. But you are probably right that that would be a good source of info.

About your last paragraph on poor tone production affecting tuning - what you say is basically correct, and it does go for brass instruments as well. An unfocused sound will also not necessarily be flat - the pitch actually fluctuates quite a bit, and can be sharp just as well as flat, which is a very interesting phenomena. Uncentered might be a better description of what I mean specifically here - the pitch is wandering out of the player's control, and it doesn't just move in only one direction when this happens. Pitch tends to raise, for instance, particularly when the player is straining. Overall, though, the timbre of a very unfocused sound will be dull (which is why it often sounds flat even when it may actually be sharp in pitch), weaker, and often airy in the case of wind instruments. There will also be lots of "fuzz" on the edge of the sound. Some jazz musicians cultivate this type of sound for expressive purposes, and bend the pitch quite a bit. This is where the old tuning joke "close enough for jazz" originates. Another example would be of a brass player with alot of "edge" to the sound - they may sound very loud up close, but "edge" will not carry out into the hall very well on it's own - there must be a good core to the sound.

As Mr. Tennis brings up, though, how all this relates to what audiophiles call "warmth" is another question. Even if "warmth" is called a "coloration", I think Bryon is right in asking is this a bad thing? In the case of an orchestral recording, equipment that makes the sound "warmer" is almost certainly also making it more lifelike, or as Bryon would put it, faithful to the original event. I for one don't care how a piece of equipment measures, or if it is "neutral." For me, equipment that is usually described as "warm" almost always sounds better than equipment specifically described as "neutral." And then there is the recording and how (and where) it was done. To me, these are still huge factors in the perception of "warmth," despite my education I have here received on electronics, and my realization that they do manipulate harmonics quite a bit more than I understood.

The definition of warmth in audio as defined by the person who introduced the word to the lexicon of audiophiles is in this thread; see J. Gordon Holt. I suggest the following: it has been used for decades. If the definition is clear, then there is little reason to tinker with it. If we need new words to describe something similar, let's find new words, and not confuse them with existing terminology. If the existing definition doesn't agree with ones interpertation, too bad, find a new word for what your trying to convey, no reason to muddy the waters with more confusion. If the definition is unclear, that's something else.

02-21-11: Almarg
…the system can certainly, as I see it, CREATE a harmonic, as a distortion product of the fundamental frequency of the note, irrespective of the existence of that harmonic in the original signal.

02-22-11: Kijanki
Harmonic distortion measurement is done by feeding pure fundamental with no overtones (sinewave) and subtracting the same fundamental from the output. Whatever remains are harmonics introduced by electronics that weren't in the original (source) signal.

The comments above are what I had in mind when, on 2/12, I wrote:

If the warmth is on the recording, and you hear it at the listening position, then the playback system is accurate with respect to warmth. Hence it is not an ADDITION. If, however, warmth is not on the recording, but you still hear it at the listening position, then the playback system is not accurate with respect to warmth. In this case, warmth is an ADDITION to the signal introduced by the playback system.

It is probably safe to say that all equipment is additive, but some equipment is more additive than others, at least with respect to the addition of harmonic content. The evidence for this can be seen in the the kind of measurements that routinely appear in Stereophile, such as Amp A and Amp B. As you can see from the graphs, Amp B adds harmonics of considerably greatly amplitude than Amp A. Hence, with respect to harmonic content, some equipment is more additive than others.

Amp A – the one with less added harmonics – is the Pass XA30.5, which is what I currently own. Amp B – the one with more added harmonics – is the PrimaLuna DiaLogue 7. The upshot of all this is that, in light of my desire for additional warmth, maybe I chose the wrong amp.

Moving on to…

The issue of whether instrument timbre is reducible to harmonic content. I am completely out of my depth here, so will remain agnostic. Having said that, IF instrument timbre is EVEN PARTIALLY reducible to harmonic content, then it reveals a flaw in the “additive approach” to playback.

Here is how I characterized the “additive approach” in a previous post…

02-12-11: Bryoncunningham
I have recently come to believe that some "additions" to the signal introduced by the playback system, while inaccuracies relative to the recording, may nevertheless be MORE accurate relative to the live event. That is because, both deliberately and accidentally, the recording process often REMOVES characteristics like warmth from the recording. Hence the ADDITION of warmth by the playback system actually makes the sound at the listening position closer to the sound of the live event.

And here is the flaw in this approach…

What is ADDED during playback will not be identical to what was SUBTRACTED during the recording process.

The reason is because, while the harmonic contents of live events are almost infinitely VARIABLE, the harmonic “additions” of playback equipment are largely CONSTANT, being persistent artifacts of a circuit's more or less fixed parameters.

Does this mean that I am retreating from my newly acquired view about the value of the additive approach to playback? No. I am merely recognizing a limit to the additive approach, namely that it cannot replace EXACTLY what is missing from the recording. Hopefully it can replace an approximation of what is missing. And that will have to be good enough.

Bryon

the fact that a word is defined does not rule out the possible arbitrary nature of the word. i am not saying holt's definition is not valid, but like any word in the english language, the duration of its usage and acceptance in communication is afctor in its utility.

by the way, what is the source of gordon holt's definition. does anyone have a reference for the definition.

perhaps if enough people accept the definition and when mentioning the word accept gordon holt's definition , it should be sufficient.

only a few people have cited holt's definition, so it seems that his definition may not be definitive.

for example, is the originator of this thread eliciting suggestions as to attain what holt defines as warmth ?

http://www.stereophile.com/reference/50/index.html