Thd (1 Viewer)

[Brian P]

I have been looking at THD #'s on amp and I see alot @ .05 some at less, some at more. Does this really mean much? .05 seems to be about the norm and I was surprised B&K wasn't lower for spec. bragging rights if nothing else. What percent becomes audible?

 

[Mark Austin]

There was a time in the 70's when the marketing departments of amp manufacturers successfully equated low THD numbers with better sound. That theory was proven false. I'm not sure of the actual audible level, but when you are looking at the respected brands in separates, you can be rest assured that that figure doesn't play much into the actual sound of the unit. Quite a few of Bob Carver and older McIntosh equipment sport some pretty high THD numbers like in the .1% range and higher, and those pieces sound very good. I wouldn't base my purchase on the THD number in the least. Pick which one SOUNDS the best to you.

 

[Dustin B]

The tube stuff a lot of hardcore audiophiles go for has THD numbers over 1%.

 

[Steve Zimmerman]

The tube stuff a lot of hardcore audiophiles go for has THD numbers over 1%

Which is absolutely laughable if you think about it. Hate me for saying this if you want to, but nobody would by tube amps if they cost less than solid state.

--Steve

 

[Mark Austin]

Which is absolutely laughable if you think about it. Hate me for saying this if you want to, but nobody would by tube amps if they cost less than solid state.

Man,....you just love to throw in your opinions as fact, don't you?

 

[Steve Zimmerman]

you just love to throw in your opinions as fact, don't you?

Well, let's see, is that your *opinion*?

--Steve (IMHO implied)

 

[Mark Austin]

Well, let's see, is that your *opinion*?

"My opinion?" I would call it more of an observation. Your statement that "nobody would buy tube amps if they didn't cost more" is an opinion, or can you tell the difference? You state that as if it is a fact, not an opinion.

 

[John Sully]

Mark,

In the 70's the problem was twofold. First, manufacturers were in a power war and they would do anything to claim high power numbers for their receivers. The distortion numbers which were claimed were typically for intermodulation distortion, a problem which amplifier manufacturers had long since conquered.

Brian,

THD was still a problem however. If I recall correctly (forgive me the memory is 30 years old) in the early sixties it was determined that 1% THD was not audible. It would not surprise me if a retest was done today that the figure would be lower since today's speakers have much lower distortion than those of the early 60's.

However, modern solid state amps produce THD 1 or 2 orders of magnitude lower than the 1% limit determined 40 years ago. Although speakers have improved, they have not improved as much as electronics. I would not worry too much about THD, unless it was getting into the .5% range.

 

[MikeH1]

I know this isn't very common but I have seen some Sony powered speakers spec'd at 10% THD. My old roomate had these and they sounded absolutely terrible. I asked for the instructions and looked at the specifications and my eyes almost fell out. And the kicker is that I believe this reading was taken at 1Khz and not full bandwidth. Needless to say they were never turned up loud. The funny thing is everybody else marveled at the little digital display that the left speaker had and actually thought these speakers were great. Take heed....