[Oedipus Rex]

Hi,

I continue my questions of trying to figure out what audiophile concepts are the real deal and what not so.

So the question is simple: if I were to blind test balanced and non-balanced system with, say, HD-650, would I be able to tell them apart?

 

[DanielCox]

I'm going to go for probably not.

 

[b0dhi]

There have been a few measurements of balanced vs unbalanced headphones (including HD650 I believe) which show an audible change in FR between the two modes. Therefore it's actually irrelevant what blind tests would result in. I was quite surprised by this but you can't argue with reality.

 

[JaZZ]

The HeadRoom graphs show measuring variations, not the effect of balanced vs. unbalanced.

BTW, I've heard an effect in direct comparison – in favor of balanced.
.

 

[Currawong]

Balanced amping is electrically different from unbalanced amping: You have voltage swing being generated in both positive and negative, not just positive.

 

[Bullseye]

If you did a proper matched leveled comparison then you wouldn't be able to discern either of them. I had some data and information about that but I would need to search for it and don't have time right now to do so. Will come back with the explanation for it once I have time.

 

[b0dhi]

Quote:

Originally Posted by JaZZ /img/forum/go_quote.gif The HeadRoom graphs show measuring variations, not the effect of balanced vs. unbalanced.

Show me where in my post I mention HeadRoom.

 

[Currawong]

Quote:

Originally Posted by Bullseye /img/forum/go_quote.gif I believe If you did a proper matched leveled comparison then you wouldn't be able to discern either of them but I've never tried this myself, so I don't really know.

FTFY.

 

[fjf]

The problem with those is volume matching. Balanced means more power, which gives more volume an an impression of more clarity. I haven't seen any properly done DBT with volume matching. Our auditory system is much less sensitive and much more accommodating that people usually believe.

 

[883dave]

Quote:

Originally Posted by Currawong /img/forum/go_quote.gif FTFY.

Good one

 

[JaZZ]

Quote:

Originally Posted by b0dhi /img/forum/go_quote.gif Show me where in my post I mention HeadRoom.

And show me where I stated that you were referring to HeadRoom graphs!

And show me which graphs you actually meant!

.

 

[Steve Eddy]

Quote:

Originally Posted by JaZZ /img/forum/go_quote.gif The HeadRoom graphs show measuring variations, not the effect of balanced vs. unbalanced. BTW, I've heard an effect in direct comparison – in favor of balanced. .

It could be measurement variations, or it could also be due to the fact that if you're using two bridged amps to get your "balance" (and really, they should just call it bridging as that's what rest of the audio industry calls it), then the output impedance will be twice as high in bridged mode than in single mode.

k

 

[Steve Eddy]

Quote:

Originally Posted by Currawong /img/forum/go_quote.gif Balanced amping is electrically different from unbalanced amping: You have voltage swing being generated in both positive and negative, not just positive.

That's incorrect.

You have both positive and negative voltage swing whether balanced or single ended.

k

 

[JaZZ]

Quote:

Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif It could be measurement variations, or it could also be due to the fact that if you're using two bridged amps to get your "balance" (and really, they should just call it bridging as that's what rest of the audio industry calls it), then the output impedance will be twice as high in bridged mode than in single mode.

HeadRoom amps have low enough output impedance to not affect frequency response either way.

The results are very contradictory – that's why I'm sure that they're due to measuring variances.
.

 

[Steve Eddy]

Quote:

Originally Posted by JaZZ /img/forum/go_quote.gif The results are very contradictory – that's why I'm sure that they're due to measuring variances..

The Headroom graphs bring up other questions.

Were they made using the same headphone? Or were they made using two different headphones, one stock, and the other terminated for bridged output?

If they were the same headphone, did they make sure that the same driver (i.e. left or right) was used for making the measurements?

Also, was the drive level kept the same for both measurements or were they driven with a higher level in the balanced measurement?

Because a headphone doesn't know "balanced" from a hole in the ground. All it knows is the voltage across its terminals and the output impedance of the source driving it. And if both of those remain consistent, there's simply no earthly reason for any change in frequency response between "balanced" and unbalanced.

k