Energy Veritas 2.4i vs. Axiom M80ti - a blind listening test.

[craigsub]

I see, then at what point do they become audible?

What you need to look at is the sensitivity of sound at the frequencies at which the harmonics are being presented. For example, 1000 - 1500 Hz is band which is most sensitive to the typical listener. Above and below that, our ears are less sensitive.

If you want to try an experiment, this is an informative blind test - take a decent SPL meter, and run something like a stryke audio disc at varying frequencies. Run a 2000 Hz signal @ 80 dB then, run a 8000 Hz signal, and have someone adjust the volume until it sounds just as loud to you as did the 200 Hz tone. You will likely find that the 8000 Hz signal is several dB higher when your ears "call it even".

Now imagine trying that 2000 Hz signal at 105 dB and then trying to hear additional 61 dB signals at 4000, 6000 and 8000 Hz (the most likely locations for the bulk of harmonic distortion). The 105 dB will be factoring in a pair of speakers with typical room gain for all tones produced. Edit: This is based on the 95 dB, 4 Pi THD+N curve from a single M80.

A speaker producing distortion with a fundamental at 500 Hz will have its first 3 harmonics at 1000, 1500 and 2000 Hz - which will be much more audible than the same THD +N with a 2000 Hz fundamental.

 

[silversurfer]

Thanks Craig, but I don't think it answers my question.

You said that the distortion in the graph is inaudible, at what level does it become audible?

edit: Typo, I ment you said it was inaudible.

 

[craigsub]

Thanks Craig, but I don't think it answers my question.

You said that the distortion in the graph is inaudible, at what level does it becmore audible?

That is somewhat like trying to answer "When is it cold outside?" ... Audible THD does not have a simple answer, as it varies from frequency to frequency and person to person. In loudspeakers, some will tell you at 10 % (- 20 dB), THD is audible. Others will tell you 1%, (- 40 dB). I have never seen a formal, blind study on this.

However, I can tell you that I have never detected THD levels, with a speaker, under blind conditions and under 3.16 % THD (-30 dB).

 

[silversurfer]

OK then, getting back to my statement, I said the distortion may be an issue for "some" people. Isn't that a correct statement then?

 

[craigsub]

OK then, getting back to my statement, I said the distortion may be an issue for "some" people. Isn't that a correct statement then?

Is it possible ? Yes. Anything is possible. I am trying to convey to you, with some antecdotal ideas, the difficulty of what you are asking "is it possible?".

Using a single loudspeaker, and the fact that we are dealing in magnitudes of amplitude in a co-located scenario (meaning the speaker's fundamental and THD + N is coming from the same place), each 6 dB difference between the fundamental and the THD +N requires a doubling of speakers playing the THD + N against the single speaker playing the fundamental.

In plain English, let's look at this -38 dB level between the peak at about 2200 Hz and the 95 dB fundamental, and for easy math, we will call it -36 dB.

To further simplify this, let's say ALL the THD+N was at the first fundamental, or 4400 Hz.

If you had one speaker playing the 59 dB @ 4400 Hz, The Fundamental would have SIXTY-FOUR speakers, each playing at the same 59 dB, totalling 95 dB.

To answer your question with a question - Do YOU think you could hear one speaker playing a single, 59 dB, 4400 Hz tone while you were standing the same distance from SIXTY-FOUR speakers, EACH playing a 59 dB, 2200 Hz tone ?

I am off to watch "Rudolph" with my kids. Back in an hour. Kick this around, and tell us what you think ...

 

[silversurfer]

You said 58dB was insignificant, all I am asking is at what level, in your opinion, does it become significant.

Have fun with Rudolph. I'm out for the rest of the evening. Merry Christmas!

 

[craigsub]

You said 58dB was insignificant, all I am asking is at what level, in your opinion, does it become significant.

Have fun with Rudolph. I'm out for the rest of the evening. Merry Christmas!

Actually, you first suggested that

The distortion numbers at 2-4k on the Axioms is right in the range of where our hearing is most sensitive, that could cause issues with some

I doubt anyone can hear a THD+N level 38 dB down from a 95 dB fundamental @ 2200 Hz, especially under and honest, blind test. You were suggesting this could be audible. Perhaps you could point to some blind tests which prove this.

 

[silversurfer]

I'm not saying it is or isn't, I just want to know what you think is, since you said it isn't. (who's on first?)

 

[craigsub]

I'm not saying it is or isn't, I just want to know what you think is, since you said it isn't. (who's on first?)

And I answered pretty extensively. I also asked you to consider a lot of variables, and to think it through. You want an easy, absolute number for an answer, and there isn't one.

I can absolutely tell you neither the Axioms nor the Energies ever had any audible distortion in this test.

 

[Tomorrow]

And I answered pretty extensively. I also asked you to consider a lot of variables, and to think it through. You want an easy, absolute number for an answer, and there isn't one.

I can absolutely tell you neither the Axioms nor the Energies ever had any audible distortion in this test.

...and where were you Craig "Shifty" Sub, on the night of June 15?! ...and no fake alibis.

Do you really really really believe there was no evidence of distortion? LOLOL. (Just kiddin' around here, SS.)

Good work, as usual Craig. But I'm wondering if you don't subliminally enjoy the abuse that comes with shootout reviews. Though, they were pretty gentle on you this go-round. For me, as always, appreciated your info.

Merry Christmas and a happy 2006 filled health and good cheer.

 

[craigsub]

RJ, SS and the rest of the Audioholics gang ...

Merry Christmas !!

ps ... and ALL the speakers distorted heavily ...

 

[silversurfer]

And I answered pretty extensively. I also asked you to consider a lot of variables, and to think it through. You want an easy, absolute number for an answer, and there isn't one.

I can absolutely tell you neither the Axioms nor the Energies ever had any audible distortion in this test.

That's fair, but your first answer was a simple "it is inaudible", now you are saying there are many variables, which is what I said in regards to how a speaker sounds(ie. not just the FR).

What purpose do the distortion graphs serve then?

 

[craigsub]

That's fair, but your first answer was a simple "it is inaudible", now you are saying there are many variables, which is what I said in regards to how a speaker sounds(ie. not just the FR).

What purpose do the distortion graphs serve then?

When you decide to exercise intelligence, and think about several of my posts, anectdotal questions, and the logic behind those questions, and work REALLY hard, perhaps you will figure out some answers.

 

[silversurfer]

When you decide to exercise intelligence....

Ahhh...that's the Craig we know and love.

Why the need to answer a question with a question, or with a shot? We are friendly here, no?

You stated 58dB's of distortion was not audible, you had a set of conditions. OK, fine, I will not dispute it. My simple question was how many dB's will it take to be audible? Lets make it real simple for you and use the same conditions as you came up with in your no audibility at 58dB.

You are able to give a simple answer of "no" for audibility at 58dB. So in your mind, there must be a threshold, right?

If in as much I am being unintelligent, you are beating around the bush. So instead of running, what do you think the threshold is under the same conditions?

 

[Tomorrow]

Ahhh...that's the Craig we know and love.

Why the need to answer a question with a question, or with a shot? We are friendly here, no?

You stated 58dB's of distortion was not audible, you had a set of conditions. OK, fine, I will not dispute it. My simple question was how many dB's will it take to be audible? Lets make it real simple for you and use the same conditions as you came up with in your no audibility at 58dB.

You are able to give a simple answer of "no" for audibility at 58dB. So in your mind, there must be a threshold, right?

If in as much I am being unintelligent, you are beating around the bush. So instead of running, what do you think the threshold is under the same conditions?

Silversurfer,

Go enjoy your Christmas with friends and family. You've beaten this one to death, already. Peace.

...and good cheer.

 

[craigsub]

Ahhh...that's the Craig we know and love.

Why the need to answer a question with a question, or with a shot? We are friendly here, no?

You stated 58dB's of distortion was not audible, you had a set of conditions. OK, fine, I will not dispute it. My simple question was how many dB's will it take to be audible? Lets make it real simple for you and use the same conditions as you came up with in your no audibility at 58dB.

You are able to give a simple answer of "no" for audibility at 58dB. So in your mind, there must be a threshold, right?

If in as much I am being unintelligent, you are beating around the bush. So instead of running, what do you think the threshold is under the same conditions?

Your opening salvo was this :

The distortion numbers at 2-4k on the Axioms is right in the range of where our hearing is most sensitive

You were wrong here. The most sensitive range is 1000 to 2000 Hz, plus you need to understand what the various distortions are. There is harmonic distortion, which typically will have the most content, IM distortion, and noise. Harmonic distortion is based on multiples of the fundamental.

For the frequencies in question, the harmonics START at 4000 Hz, and go up in frequency from there. That is quite out of the most sensitive range of human hearing.

If you want to know why I said "when you are ready to exercise intelligence", I never said 58 dB was on its own inaudible, I said:

with a 95 dB signal at 2000 Hz, all the harmonics at 4000, 6000, 8000 Hz, etc, PLUS any noise ... add up to 58 dB. That is not going to be audible over a 95 dB fundamental @ 2000 Hz.

That is not the same as saying 58 dB is inaudible. As for the remainder of the exchange, I had given you several ideas, and experiments to try for yourself, so you could actually find out what YOU hear in the ways of distortion. It is quite clear you have no interest in being a positive influence in this discussion, as you have displayed no interest in trying anything for yourself.

I never said you lacked intelligence, I was hopeful that you would exercise some. You are not interested in a dialogue, you want to run an interrogation. It would be more fun if you buy your own TrueRTA package, a proper microphone, and run some blind tests for yourself. I promise not to try to pin you to any absolute answers, too ..

 

[Ajax]

The Devil made me do it!

 

[silversurfer]

OK, lets back up, I am not disputing anything you stated. Maybe too much egg nog on my part.

with a 95 dB signal at 2000 Hz, all the harmonics at 4000, 6000, 8000 Hz, etc, PLUS any noise ... add up to 58 dB. That is not going to be audible over a 95 dB fundamental @ 2000 Hz.

Using your above statement, at what level do the harmonics and noise need to be for audibility?

 

[craigsub]

OK, lets back up, I am not disputing anything you stated. Maybe too much egg nog on my part.



Using your above statement, at what level do the harmonics and noise need to be for audibility?

Typically, most people will start to identify THD + N levels of about 10% under blind conditions, or at -20 dB. If they are staring at a graph showing - 40 dB (1%), the same people will normally hear that.

 

[silversurfer]

OK, so 75dB in this instance?

I don't have any experience in listening for distortion levels, but I thought the 10% level was associated with subwoofer testing, not speakers.