headphone Amplification questions

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towert7

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Hello, It seems my idea of how amplification, specifically with headphones, may be way off.

Mister X pointed out that with the way I head my soundcard setup and my Audio/Video receiver setup, that the receiver was actually "de-amping" the signal... so to speak.

I had the volume on the soundcard up to full and the receiver(Denon AVR685s) set about 1/4 of the way.
The soundcard volume was set to 100% because at this volume it would match the volume of the radio when played through the receiver.
This produced the volume I was used to. Mister X said that the volume if the headphoens were plugged into the sound card would be louder then the receiver, which it was.

So what does this mean? Does this mean the receiver was not amplifying the signal? Was it amplifing the signal and then reducing it?

Would it be better to set the sound card low, and the receiver higher to actually increase the volume over the sound card?

And how exactly does the headphone amp work in relation to all of these questions?
I remember reading a DIY headphone amp, and it said measure the voltage at the highest listening level of the sound card / other audio source, and have this be the minimum voltage.................

I'm confused.

~Thanks
 
I'm not familar with the audigy's control panel. All soundcards are similar though.

For example with the e-mu you want the volume set at 0db in it's user interface, then adjust the volume with the amp. This provides the cleanest signal from the card to the amp.
 
cypher22 said:
I'm not familar with the audigy's control panel. All soundcards are similar though.

For example with the e-mu you want the volume set at 0db in it's user interface, then adjust the volume with the amp. This provides the cleanest signal from the card to the amp.
Click to expand...
Well, with the Audigy 2 ZS, the volume controler is just a bar with tic marks on it.
It goes from 0% to 100% and there is also a dB listed as well.
0% = null
1% = -48dB
50% = -15dB
90% = -3dB
100% = 0dB

Your best guess is mine.

Again, when I had the card set to 100% (0dB), it would match that of the built in FM tuner in my receiver for volume. This is why I had it at 100%.
 
No offense guys, but running an Audigy at 100% is one of the worst things you can do to a poor amplifier/receiver as the sound card's output is "clipping" (producing distortion, basically) horribly at that level, which is clearly audible at about >60% (I run mine at around 55% as it sounds decently clean around here with plenty of power in the signal to drive a properly setup amplifier).

To get proper output of your headphones, a quality headphone amplifier with the gain set properly can allow you to run the soundcard below clipping with minimal harmonic distortion and more volume/output than you could ever dream! ;)

Just so you know, MisterX knows his audio and builds some of the highest quality audio reproduction equipment on the market.
 
hybridamp said:
No offense guys, but running an Audigy at 100% is one of the worst things you can do to a poor amplifier/receiver as the sound card's output is "clipping" (producing distortion, basically) horribly at that level, which is clearly audible at about >60% (I run mine at around 55% as it sounds decently clean around here with plenty of power in the signal to drive a properly setup amplifier).
Click to expand...
Clipping in the treble or bass? Eaither my Beyerdynamic DT990pro's are'nt good enough to notice, or my ear's just arn't that attuned............. or im not playing music that exibits these clipping sounds (any obvious suggestions to produce clipping?).
 
So I should only have my volume level (for windows) NOT be at 100% when I am amping the signal to my speakers?

I should have it at like 30-50%?

I never thought of that.
 
I'm no expert, and all the following is just whatever information I've gleaned from reading www.headfi.org. I recommend you go there for information on headphone audio, these guys are fanatical about it.

My understanding of it is this, an amp basically takes a signal and adds "power"(or gain) to it.

Ideally a good amp should be able to take this signal and add gain without distorting the signal. All amps can add volume by turning up the gain, but crappy ones will give poorer fidelity. However, if you've got a crappy source, after the amping what comes out will always be crappy.

The soundcard(Odds are that you've got a Creative one, which are good for gaming but average at best for audio quality is what I hear) itself can only increase the volume so far without losing quality. When you ramp the volume to the max on the soundcard, you're degrading the quality before running it into an amp. You should try evening out the volume levels on every connected unit so that none of them are pushing their limits too far and degrading the quality.

Impedance is a rough indicator of the "power" level for best performance. Soundcards generally have 1/8th jacks and low impedance( I hear sources are supposed to have low impedance ideally anyway). If it's too low for your headphones, you'll find that you'll need to crank the volume up unreasonably high on the card to get adequate sound, and like I said, cranking it all the way up will mean the resulting sound will have less quality. That's why some headphones need an amp for best performance, they'll remedy the low impedance by filling in the gap for you. It's not an issue of more is better either though, ideally the impedance should match the headphone's listed requirement. And higher impedance requirements on headphones don't necessarily mean they perform better either.

There's a good chance I may have misinterpreted some of what I'd read on those forums, so I recommend you go to www.headfi.org yourself as well in order to be sure.
 
^^^

I'm an avid member of headfi and I think you hit it on the head.

I have 2 amps - a HeadAmp GS1 for my HD650 headphones and a Rotel RB1070 for my Sonus Faber speakers.

I never thought about straining the analog out of the soundcard though I should have as I know its not good to push the amp past a certain point when THD begins to rear its ugly head.
 
Pinipig523 said:
So I should only have my volume level (for windows) NOT be at 100% when I am amping the signal to my speakers?

I should have it at like 30-50%?

I never thought of that.
Click to expand...
FYI I found on my exigy the most audio power is being produced at 65~75% above that clipping in the bass occurs.
Why is this important, well imagine a large low freq sine wave and on top of that multiple layers of higher freq lower amplitude sine waves (how an audio signal looks to some extent). When an amp circit clips in the power amplification stage usually it doesn't just flatten the peek of the signal but takes a 'bite' out of it. Now the bass will typically clip first cause that is where the most current is, now layer all those smaller high freq sine waves on the clipped bass signal, there simply isn't as much area under the whole sound wave as there was before, as area = power = apparent volume it delivers more audio power to back off the amp a bit so that the bass doesn't clip.

Note: this is over simplified and taken from when I did basic audio tech training (about 10 years ago), and it probablly wrong on many levels
 
Hmmm, guess the e-mu cards are different. If I adjust the volume on the card anywhere in the +db range clipping occurs. Having it set at the reccomended 0db, there is no clipping or distortion.
 
So for a digital connection (HDA Mystique 7.1), is it ok to set the volume in windows to max or should that also be brought down?
 
ds- said:
So for a digital connection (HDA Mystique 7.1), is it ok to set the volume in windows to max or should that also be brought down?
Click to expand...
Hm, I wonder how that works. Does increasing the volume have a major impact on the digital connections?

Currently my Audigy 2ZS plat is connected to my receiver though a digital coaxial.

As for the THN, I can't tell the diffrence between eaither having the sound card at 100% and the receiver at -36, or the sound card at 50% and the receiver at -20(on a range of -70 to 70). I just don't hear a diffrence when using heapdhones. On the other hand, If I were to say, change the bass one notch higher on the receiver, I can hear a noticible diffrence in the noise.
 
towert7 said:
As for the THN, I can't tell the diffrence between eaither having the sound card at 100% and the receiver at -36, or the sound card at 50% and the receiver at -20(on a range of -70 to 70). I just don't hear a diffrence when using heapdhones. On the other hand, If I were to say, change the bass one notch higher on the receiver, I can hear a noticible diffrence in the noise.
Click to expand...
As long as the digital side of things is stable you should be fine up to 0dB, beyond 0dB I'm not to sure as I've not really got any background in modern sound cards.
 
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