Devialet Expert isn't good in showing secondary harmonics?

[Jeffaz]

A brazilian audio forum person, who represents a well-known cable manufacturer, and himself an experienced audiophile, told me that Devialet Experts line aren't good enough in showing secondary harmonics.

This conversation took place when I was interested in buying speakers cables from him.

Have any of you of Devialet Chat ever heard about this "secondary harmonics" issue?

Jefferson

[thumb5]

Perhaps he means that Devialet amplifiers have very little harmonic distortion?  It's the only interpretation I can think of that's consistent with their excellent measured performance.

[Damon]

I too would think that the 'secondary harmonics' item must be distortion; One of the frequently mentioned strengths of the Devialet expert amplifiers is that they are exceptionally revealing. They don't have tubey 'bloom' to the midrange, which many persons like. Although the science and math of it is beyond me, I understand that some harmonic distortion modes are pleasing to the ear. That too could be the harmonics your acquaintance is referring to.

[Confused]

I've been doing a bit of thinking (DANGER!!!!) about what an amplifier actually has to do, in terms of it's job of taking an input signal, and 'amplify' it, creating specific volts / amps to feed a speaker coil to accurately control the movement of a speaker cone, to reproduce that original signal as a sound wave.

If I think about a guitar string, I can easily envisage what it means for that string to vibrate with first or second harmonics, and how this produces a different sound. However, how does the second harmonic present a specific challenge for an amplifier, in that it would work well with the first harmonics of any frequency, but struggle with some second harmonics? Here I am stumped! Utterly stumped.

I quite liked Damon's tubey bloom theory, in that maybe the Devialet is very accurately not doing something. Something that some amplifiers might do that 'colours' the sound fractionally, but subjectively sounds pleasing.

As for Devialet amplifiers being good at first harmonics, but struggling with second harmonics? Well, I'll use a true audiophile phrase here; utter foo!

(it did get me thinking for a while though, but I'll stop now)

[thumb5]

I quite liked Damon's tubey bloom theory, in that maybe the Devialet is very accurately not doing something.  Something that some amplifiers might do that 'colours' the sound fractionally, but subjectively sounds pleasing.

Exactly.  Aren't valve amps supposed to sound good partly because they tend to have a lot of even-order harmonic distortion?  So if  one gets used to that sound I can imagine that the Devialet would sound a bit "clinical" by comparison.  It's the old dilemma about whether you'd rather have something that sounds "accurate" or "nice", I think.

[ogs]

If your cable designer meant second harmonic distortion then the only measurement we have as far as I know is from the Stereophile test of D-Premier: http://cdn.stereophile.com/images/113Devifig08.jpg Here the second harmonic distortion component is just a little lower in level than the third. The general distortion level is very low.
In a normal single ended tube amp you'd have fairly strong second, fourth etc harmonics while third, fifth etc would be lower in level. Damon's reference to 'bloom' is a good description of the typical tube sound. The same could more or less be true for a class A transistor design. An old theory I've heard is that an amplifier stage should have a distortion signature with second harmonic a little stronger than third, then fourth, fifth, sixth etc with decreasing level. Modern amps (not just Devialet) tend to have more odd order harmonic distortion than even.
The statement you refer to is fairly non-technical and a bit strange...

[Pim]

Maybe he means the second time you hear the same thing, like the echo in a live recording perhaps?

Anyway, Anything named ;secondary' shouldn't be a 'primary' concern 

[Jeffaz]

Perhaps I should have told "harmonics of 2nd order", to be more precise. But, reading your comments, I'm concluding that this guy, the cable's dealer, prefers tube amps, and Devialets are too "digital" for him. Some people put labels on things: Class D -> Oh, no! -> Digital -> Bad.

[Hifi_swlon]

Can people actually hear these things?

I don't mean 'does it make a difference', I mean more like someone plays you some music through a new amplifier and you, having years of listening experience, say 'thats absolutely lovely, but it's somewhat lacking in second harmonics, which I'm finding a touch lower than the 3rd harmonics - I think if we just had a 10% increase in the 2nd harmonics, things would really fall into place with a lovely balanced coherent sound' type thing…..

I obviously dont know what Im talking about, but Im always fascinated when people can identify such things. On lots of forum posts I've read recently people were able to hear all sorts - jitter in the order of picoseconds, USB grounds, specific FIR filters etc etc. I doubt I'd know what any of these things sounded like unless I was guided through it in a lab environment.

[Xander]

I do think he wanted to sell you some cables to fix this?!

:-)