5% THD to .000 THD SOUND


I was searching the amplifiers available and noticed quite a big difference in THD specs from model to model. Example.. One of the best amplifiers Kondo Audio Note $150k Kagura has 5% THD and by reviewers definition sounds like an amazing amplifier. Now compare $ 30k  Devialet with the lowest 0.000% THD on the planet. Both at the opposite end of design yet both sound amazing.. according to reviewers, I havn t heard either. SN/R  133 by Devialet and a lot less by Kagura. I realize an amplifiers sound can t be based by Specs alone.  If the specifications are not that important to the sound, why list them? They must be a way of determining sound, quality, and system synergy of an amplifier? A whole lot of amplifiers purchased on the net haven t been heard before and I believe the decision to purchase is made by reviewers point of view, specifications and word of mouth of other owners and buyers pocket book. By looking at specs of Devialet and NOT knowing the prices of Kagura and Devialet I would of gone with the Devialet just based on specs alone for the impression of it being a  great sounding amplifier.  Ive read other discussions on forum and cant quite get a handle on why BOTH amplifiers sound great. I thought High THD was a bad thing..
derrickengineer
derrickengineer

You can get minuscule distortion figures (.0001%) on a poorly designed amp with massive amount of GLOBAL feedback, and they sound rubbish.
 
The best is to get minuscule distortion under (.1%) without any or very little global feedback if possible. Some very good amp designers can get this with just LOCAL feedback around the input stage which leaves the output stage free of global feedback, this to me is the best way to go.

Amps that have 5%THD are not well designed, and are for the the crew that love their euphonic coloration's depending on the type of THD. 

Cheers George     
Gdnrbob & Bombaywalla, thanks!

I am in essential agreement with most of what has been said above. I would commend the following thread to the OP and anyone else who may be interested, in which I, Atmasphere, and others posted on the subject of amplifier specs in general and THD in particular:

https://forum.audiogon.com/discussions/amplifier-specs-does-they-matter

One of the basic points I stated in that thread was precisely what Bombaywalla said above: Specs and measurements, including THD, can often be useful in RULING OUT potential candidates for purchase from consideration, in some cases by identifying specs that may be TOO good, and thereby may signify the likelihood of undesirable design tradeoffs such as excessive use of feedback.

Personally, regarding the specific amplifiers that were cited in the OP, if I were amplifier shopping I would probably not include either one on my short list, regardless of what the reviews may have said and even if cost were no object. An amp having a 5% THD spec, no matter how euphonic and pleasing it may sound on initial audition, would over the long term cause me to unduly focus during my listening sessions on how untrue the amp is being to the recording, rather than simply enjoying the music. And an amp having vanishingly small THD would over the long term cause me to unduly focus during my listening sessions on whether it might be introducing excessive brightness, sloppy transients, and other effects that can result from heavy-handed application of feedback, or from other techniques that may have been used to achieve those numbers.

As I see it there are more than enough well regarded amps to consider, in all power ranges, that have specs that are neither "good" nor "bad" to a degree that would raise concern. Given that, I would see little point in pursuing ones having specs like these.

Regards,
-- Al

geoffkait3,776 posts07-30-2016 4:58pm

I went out for a mild mannered troll and got a sucker on the line.


Well since you said it mr. kaits, is there a bit of quilt coming out from your magic clock thingy or by stating " got a sucker on the line" you know full well there's nothing magic about your magic clock ?
I would not rule out any amp based on specs. I would trust my ears. If something sounds good to me for 15 minutes, it will sound good to me for 15 hours as well.
There are those who think that with right speakers Kondo amplifiers are among the very best, especially for a particular kind of music. Ruling it out altogether would be unwise, I'd say. The biggest distortions we get are already there in the recordings, and the better your equipment the more you know it. And if you can't hear it - either your hearing is no good or you are in a state of denial.