Get an exclusive sneak peek into our new project. >>> Click Here
Our native mobile app has a new name: Fora Communities. Learn more.

Is there an audible difference between 0.1% THD and 0.01% THD?

32296 Views 51 Replies 26 Participants Last post by avjunkee, Mar 29, 2010

Bill Mac

Discussion Starter · Jun 17, 2008

I would like to get some opinions on whether there is an audible difference between components (pre-amp or amp) with 0.1% THD compared to 0.01% THD (or less say 0.009) From a few threads and posts that I saw mentioned that to actually hear THD it has to be in the 5% and up range. I have debated this fact with another member who claims a pre-pro with say 0.009% THD will sound better than a pre-amp with 0.1% THD. And that when I listen to music with my pre-amp (Rogue Audio Perseus with a rated 0.1% THD) he states "I must like my music full of distortion" because of the 0.1% THD rating.

My thoughts are that the difference between 0.1% THD and 0.009% is inaudible which IMO will have no bearing in the SQ of said components. This is a totally uneducated opinion on my part so I would appreciate members with more knowledge on this to give their opinion.

Thanks, Bill

Reactions: 1

1 - 20 of 52 Posts

Promo2000

· #2 · Jun 17, 2008

Dont know exactly, but the fact is: The lower the better.

rdclark

· #3 · Jun 17, 2008

The double-blind tests I've read about over the years have shown that indeed distortion measurements in the sub-1% ranges are impossible to distinguish from one another.

However, that's not to say that the equipment in question can't have meaningful audible differences for other reasons, such as tube designs vs solid state designs. There are other factors that affect the sound much more profoundly than tiny differences in THD.

It should also be noted that rated THD and actual measured THD may be two different things. Higher-end manufacturers tend to be more conservative in their ratings.

MKtheater

· #4 · Jun 17, 2008

Hi Bill,

Don't let that other thread bother you. He has never said what equipment he uses and just because he thinks his specs are better does not mean it will sound better. There is a reason why someone will not post what they own and put down alot of good equipment saying it is over priced. Many pro amps are rated at .1% distortion and other amps rated alot less. Do they both sound clean and distortion free, yes they do. He will put down many amps like ada, krell, mcintosh, and so on that are rated with very low distortion but yet will tell someone to buy a pro amp without realizing it is rated at .1% distortion because high end is just a name. He should make up his mind.

Chu Gai

· #5 · Jun 17, 2008

It depends on what the order of distortion is as to the audibility. Generally though, I wouldn't be overly concerned with 0.1 vs. 0.01%.

DougWinsor

· #6 · Jun 18, 2008

Come on bill, my opinion bugged you that much? We really need to put your tube pre amp on the bench and see how high the distortion gets. Did you look up why some people still use tubes for the guitars and why they ramp up the distortion over 1%?

Bill Mac

Discussion Starter · #7 · Jun 18, 2008

6

Quote:
Originally Posted by DougWinsor /forum/post/14105668

Come on bill, my opinion bugged you that much? We really need to put your tube pre amp on the bench and see how high the distortion gets. Did you look up why some people still use tubes for the guitars and why they ramp up the distortion over 1%?

DW,

No honestly your opinion did not concern me in the least and I am sure that bothers you

. I am just curious as to what others here on the forum think of this. I believe the difference to be inaudible but maybe I am wrong. I appreciate opinions from others whether they are the same or differ from mine. That is the difference between you and myself is that I have an open mind. I am open to different opinions and thoughts. I do not try to stuff my opinions down peoples throats like yourself

.

I have no interest in bench testing my Perseus. As I said before I am more interesting in listening to my system and enjoying it than bench testing it. Odd concept for you to consider is it not

? But if it interests you why don't you buy a Perseus and bench test one yourself.

Why would I care if people use "tubes for the guitars" and that "they ramp up the distortion over 1%"? Why would I want to look up this in the first place? Does it have any bearing on home audio components? If they are happy with the sound I think thats great. I thought this was a discussion about THD with home audio pre-amps and amps by the way

. I find it quite funny how some people go to great lengths to push their agenda and look quite foolish doing it. Rock on Spec Man

!

Thanks to everyone else for their thoughts on this

.

Bill

See less See more

gurkey

· #8 · Jun 18, 2008

Quote:
Originally Posted by Bill Mac /forum/post/14106610

DW,

No honestly your opinion did not concern me in the least and I am sure that bothers you

. I am just curious as to what others here on the forum think of this. I believe the difference to be inaudible but maybe I am wrong. I appreciate opinions from others whether they are the same or differ from mine. That is the difference between you and myself is that I have an open mind. I am open to different opinions and thoughts. I do not try to stuff my opinions down peoples throats like yourself

.

I have no interest in bench testing my Perseus. As I said before I am more interesting in listening to my system and enjoying it than bench testing it. Odd concept for you to consider is it not

? But if it interests you why don't you buy a Perseus and bench test one yourself.

Why would I care if people use "tubes for the guitars" and that "they ramp up the distortion over 1%"? Why would I want to look up this in the first place? Does it have any bearing on home audio components? If they are happy with the sound I think thats great. I thought this was a discussion about THD with home audio pre-amps and amps by the way

. I find it quite funny how some people go to great lengths to push their agenda and look quite foolish doing it. Rock on Spec Man

!

Thanks to everyone else for their thoughts on this

.

Bill

It's not the absolute magnitude of the distortions but the distribution and relationship of harmonics.

Because there are harmonic, intermodulation and phase components etc. of distortion in general terms, the distribution and interrelationship determines in the end, what is audible in one way or the other.

The absolute magnitude below 0.1% is rather insignificant and may even indicate a rather large amount of feedback applied, which might hamper signal resolution in complex signal mixtures and so on.

DulcetTones

· #9 · Jun 18, 2008

gurkey,

interesting what you said about harmonics and ties in well with an article that looks at "The hidden harmonics behind THD".

I am including the link just for reading, I want to stress there is no need to respond in various ways arguing for/against what is in there.

It is just food for thought.

http://www.nutshellhifi.com/library/FindingCG.html

Edit:

Also I agree with the other aspects you mentioned as well.

Cheers

DT

See less See more

RCbridge

· #10 · Jun 18, 2008

Do you have Golden Ears??

FMW

· #11 · Jun 18, 2008

"Is there an audible difference between 0.1% THD and 0.01% THD?"

No. THD measurements below 1% are not audible.

Bill Mac

Discussion Starter · #12 · Jun 18, 2008

2

Quote:
Originally Posted by DulcetTones /forum/post/14107062

gurkey,

interesting what you said about harmonics and ties in well with an article that looks at "The hidden harmonics behind THD".

I am including the link just for reading, I want to stress there is no need to respond in various ways arguing for/against what is in there.

It is just food for thought.

http://www.nutshellhifi.com/library/FindingCG.html

Edit:

Also I agree with the other aspects you mentioned as well.

Cheers

DT

DT,

Thanks for the link very interesting read. Although I have to admit a good portion of it was over my head

. I found the last four paragraphs to be very interesting. I thought this paragraph to be especially interesting:

" If it were why do stereo LP's made 40 years ago, amplified with 65-year old direct-heated triodes, sound so much better than today's digital sound played through 0.001% THD mass-fi rack stereos? The differences between mass-fi and true high fidelity are as plain as day to an (open minded) listener"

Whether you agree or not with the above quoted paragraph I think the key is to have an open mind. If you do not I feel you miss out on a lot of very good music listening. And to me that is what it is all about

.

Bill

See less See more

oztech

· #13 · Jun 18, 2008

I think most of the problem with the sound we hear today is bad mastering ,running

the mix hot with so much compression the dynamics from a quite passage to crescendo

is lost.

JOHNnDENVER

· #14 · Jun 18, 2008

distortion(s) can defiently have postive effect on the sound. it can also have negative effects on the sound.

1% is the generally accepted standard for it being inaudible.

But once again? Distortion specs are misleading. They can make that piece of equipment say darn near anything they want on a given test. I don't even look at the spec when selecting equipment.

gurkey

· #15 · Jun 18, 2008

The problem with all those technical specs is, that there is little to no resemblance, what the final sound quality will really be.

Look at all those Asian high-tec monsters, which sport an endless list of technical innovations and features, but may sound quite dull at the end, despite all those extravagances.

Average sound quality has improved with the years, but there seems to be no real correspondence between technical specs (except may be noise) and superior sound quality (unfortunately).

Bill Mac

Discussion Starter · #16 · Jun 18, 2008

Quote:
Originally Posted by JOHNnDENVER /forum/post/14108243

distortion(s) can defiently have postive effect on the sound. it can also have negative effects on the sound.

1% is the generally accepted standard for it being inaudible.

But once again? Distortion specs are misleading. They can make that piece of equipment say darn near anything they want on a given test. I don't even look at the spec when selecting equipment.

John,

So would it be true that anything under 1% distortion is really unaudible and really not going to effect SQ? I agree with you and that I do not consider specs when buying audio equipment. I am looking for overall SQ than being able to say any one of my components has 0.0001% THD.

When looking for a specefic component I look at reviews (professional and from members here) then narrow it down to as few as possible. Then listen to as many of those choices as possible in my system then make a decision on what sounds good to me.

Bill

See less See more

JOHNnDENVER

· #17 · Jun 18, 2008

As an audio engineer for a couple of decades. The 1% spec has been taught in schools at the generally accepted number.

You ears and preferences are the most important factor here.

It was funny though... There is a whole host of more vintage bargain equipment and many not so bargain and not so vintage as well, that ists the spec at .9 and you have to wonder about it. Especially knowing the below 1% figure has been bantered about for so many years now.

M Code

· #18 · Jun 18, 2008

3

In 1973..

Dr. Amar Bose during the hearings for the FTC power output measuring standards hearings held in Washington DC, stated that threshold for THD distortion to be audible was 1%..

Also I wonder if anyone knows what the audible threshold of THD% is through a loudspeaker..

The actual THD specification value will likely surprise many..

I don't hear any THD through my Wave Radio..

OK.. Boys flame away..

See less See more

DougWinsor

· #19 · Jun 19, 2008

Quote:
Why would I care if people use "tubes for the guitars" and that "they ramp up the distortion over 1%"? Why would I want to look up this in the first place? Does it have any bearing on home audio components? If they are happy with the sound I think thats great. I thought this was a discussion about THD with home audio pre-amps and amps by the way. I find it quite funny how some people go to great lengths to push their agenda and look quite foolish doing it. Rock on Spec Man!

Since you had no experience with tube gear before your pre amp I thought I would try something easy so you could get your mind around the "tube" sound. Some people like high distortion and some don't, you obviously like your sound with high distortion numbers. Why don't you look at a tube amp and crank that THD up to 1-10% and see how it sounds.

jmschnur

· #20 · Jun 19, 2008

It is interesting that no one has mentioned the speakers distortion in this discussion I would hazard a guess that a system's distortioni.e source to speaker would make a difference to discerning listeners. However most speakers have distortion in several frequency ranges if not most that exceed the distortion of the pre amp/amp chain. Thus one could not tell the difference between a .1% and .01% amp if the speaker had distortions in the 1% range for a particular frequency at a particular sound level.

joel

1 - 20 of 52 Posts

This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.