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

02-10-11: Learsfool
...you can have a system that measures very well in the frequency response that still sounds very cold (or doesn't resolve timbre correctly) - I have heard many of them in dealer's showrooms - so that is why I do not equate "warmth" with frequency response. Harmonic structure does come much closer to my conception.

Learsfool - I agree that a system that measures well in frequency response can nevertheless fail to sound warm. In other words, balanced frequency response isn't a sufficient condition for the perception of warmth. But that doesn't mean that balanced frequency response isn't a necessary condition for the perception of warmth.

I suspect that, to be perceived as warm, a system must have a balanced frequency response, within some range. (BTW, I don't think "balanced" is necessarily the same thing as flat.) I think that bright systems, or systems with very little bass, are less often perceived as warm. And I think that systems with elevated upper bass and/or lower midrange are more often perceived as warm. In addition, Al pointed out how anomalies in frequency response, like those created by comb filtering, might conceivably diminish the perception of warmth.

Taken together, these considerations seem to suggest that there is a link between frequency response and the perception of warmth, even though, as you point out, some systems that measure well in frequency response nevertheless fail to sound warm.

This is not just about semantics or logic. It's about HOW TO GET warmth in your system, when you don't have it. If warmth is both a matter of frequency response and harmonic content, then manipulating one of those variables could presumably contribute to the perception of warmth.

RE: The use of frequency response to increase warmth. I think efforts to balance frequency response are a good idea, whether it's done with tone controls, eq, or room treatments. I use all three, but would still like some additional warmth. One way to get it, in light of the observations above, might be to elevate the upper bass and/or lower midrange of my system. But I'm not a big fan of this idea. I tend to experience systems with elevated upper bass/lower midrange as uneven, slow, thick, or unresolving.

RE: The use of harmonic content to increase warmth. I think this is a much better idea. The obvious way to add harmonic content is to add tubes, as several posters have pointed out. Unfortunately, in my case, that would mean changing both my amp and my speakers, since my speakers aren't very tube friendly. That could get expensive, but I'm considering it.

Bryon

Bryon,

Many confuse foggy muddy systems that can only play one or two of Carol Kidd's ballads as the ultimate warm systems.

Making a system foggy and rolled off masks the lack of dynamic linearity, stability, and distortion from transients.

A tube power amp may not necessarily be warm. Listen to the recent Audio Research amps. They are anything but warm.

I listened to a pair of Electra 1027Be's a few years ago with Chinese Cayin gear and they didn't sound bad at all.
I don't think they aren't tube-friendly.

I really think you ought to try a tubed DAC and a tube preamp. Just borrow a tube preamp from a friend and see if it gets you the sound you want.

FWIW, I think someone has already touched upon one of the critical elements to the appearance of warmth in a system with balanced tone, that is the proper rise and decay of the signal without which balanced tone becomes meaningless.

IMHO proper rise and decay times, when everything else is right, is what makes good recordings sound more like the natural sound of instruments. Unfortunately this is not achieved by any add on processor, you have to get it designed into your components.

IME, the most critical time element is adequate decay. Too short a decay and the tone loses natural harmonics and sounds bright/clinical. May help superficially in creating the sense of a large soundstage, but in the long run fatigues. Too long a decay and the sound becomes muddy. Rise time is important too, but just less so I think, except for the effect it has on those instruments which have a fast/sharp rise, such as percussion instruments.

It might be important to consider how the natural harmonics of an instrument occur in the first place and what constitutes harmonics as the term applies to an audio system.

I'm not so sure equalizers or tubes are the method to be used to obtain 'warmth' if that term is not to be equated to frequency response or tonal balance. But, if your system lacks adequate rise and decay tubes and equalizers etc may be the only way.

Just a thought Bryon.

I put a space heater in my listening room.

Seriously, I associate good warmth when I hear it with good clarity and detail in the mid-range. If I listen hard, I might detect some "warmth".

On teh other hand if all I am thinking is "gee that sounds really warm", I am probably dealing with something that is adding a pleasant (with some kinds of music at least) but not natural emphasis to my midrange. This is bad warmth to me.

02-11-11: Johnsonwu
Many confuse foggy muddy systems that can only play one or two of Carol Kidd's ballads as the ultimate warm systems.

Making a system foggy and rolled off masks the lack of dynamic linearity, stability, and distortion from transients.

Johnson - This expresses one of my concerns with changing amps. My current amp, a Pass Labs XA30.5, suffers from none of these problems.

It also raises a larger issue, which has been in the back of my mind, but has not come up yet on this thread: Whether the use of an "additive" approach necessarily entails the diminishment of resolution. I suppose it depends on what type of addition you're talking about. If the addition is low order harmonics, as you get with many tube amps, does that necessarily entail the loss of some resolution, however slight?

To be clear, even if the answer to this question is 'yes,' it doesn't eliminate the use of a tube amp from consideration. To me, resolution is a priority, but not the only priority. I would be willing to sacrifice a small amount of resolution to increase my system's warmth. But I would certainly not want to find myself with a sound that is so warm that the system's resolution was diminished in the ways you are describing. That doesn't sound appealing to me at all.

A tube dac is among the several options I'm considering, though there are those who doubt that that approach will result in much additional warmth.

02-11-11: Newbee
IME, the most critical time element is adequate decay. Too short a decay and the tone loses natural harmonics and sounds bright/clinical. May help superficially in creating the sense of a large soundstage, but in the long run fatigues. Too long a decay and the sound becomes muddy.

This is a good observation, Newbee, and something that hasn't been discussed much so far. I agree with you that systems that cannot adequately portray the decay of notes sound less warm. I never thought my system suffered from this problem, but maybe I haven't given that enough thought. I have heard systems that do a better job than mine with this subtle but significant characteristic of time domain behavior, and like you, I find that it contributes greatly to a sense of realism and beauty.

Questions: What design features of components, or component interactions, contribute to a system's ability to adequately portray the decays of notes? Are tubes inherently better at this? Is it affected significantly by the speaker driver's Q and/or the amp's damping factor?

Anyone?

Bryon