[EinZweiDrei]

is there a sound difference between feeding the signal from a DAC and 3.5mm to a desktop amp?
i know that the 3.5mm jack is already a amp itself (though not a good amp)
but i wanted to know if theres a difference in sound
between a 3.5mm from a sound card being fed into an amp by a 3.5male to RCA cable
and from a standalone dac with dual RCA cable.

 

[PurpleAngel]

Quote:

Is there a sound difference between feeding the signal from a DAC and 3.5mm to a desktop amp?
i know that the 3.5mm jack is already a amp itself (though not a good amp)
but i wanted to know if theres a difference in sound
between a 3.5mm from a sound card being fed into an amp by a 3.5male to RCA cable
and from a standalone dac with dual RCA cable.

Is there a sound difference between feeding an analog line out signal from a DAC (Digital to Analog Converter)
and the analog line out signal from a sound card, to the line in on an external headphone amplifier?
I know that the 3.5mm analog line out jack on a sound card is already an amplifier it's self (though not a good amplifier)
But I want to know if there is a difference in sound between these two line out signals, from the 3.5mm analog line out on the sound card to the RCA jacks inputs on the amplifier
and from an external DAC with dual RCA cables.
 
Is this the question you are asking?
 
When the sound cards "front" speaker output (green 3.5mm jack) is set to "speaker/line out" it will be the same analog signal sent by the line output jack on the DAC.
 
 

 

[EinZweiDrei]

Quote:

Is there a sound difference between feeding an analog line out signal from a DAC (Digital to Analog Converter)
and the analog line out signal from a sound card, to the line in on an external headphone amplifier?
I know that the 3.5mm analog line out jack on a sound card is already an amplifier it's self (though not a good amplifier)
But I want to know if there is a difference in sound between these two line out signals, from the 3.5mm analog line out on the sound card to the RCA jacks inputs on the amplifier
and from an external DAC with dual RCA cables.
 
Is this the question you are asking?
 
When the sound cards "front" speaker output (green 3.5mm jack) is set to "speaker/line out" it will be the same analog signal sent by the line output jack on the DAC.
 
 

what i mean is
soundcard 3.5mm jack(headphone and speak belong here) ->3.5mm to rca -> headphone amp -> headphone
                                                   vs.
usb DAC RCA jack->dual rca cable -> headphone amp -> headphone


from what i hear, the first one option is basically double amping. i heard that double amping is worst than single amping.
the later option seems to be a recommended setup from what i hear.

i want to know if theres a difference between sound.

 

[PurpleAngel]

Quote:

What i mean is
sound card 3.5mm jack(headphone and speak belong here) ->3.5mm to RCA -> headphone amp -> headphone
                                                   vs.
USB DAC RCA jack->dual RCA cable -> headphone amp -> headphone


From what I hear, the first one option is basically double amping. i heard that double amping is worst than single amping.
the later option seems to be a recommended setup from what i hear.

I want to know if there's a difference between sound.

If you set (in sound card's software control panel) to Speaker/Line out, it's not functioning as a headphone amplifier.
So your not double amping.
Which sound card are we talking about?
 
 
 

 

[EinZweiDrei]

Quote:

If you set (in sound card's software control panel) to Speaker/Line out, it's not functioning as a headphone amplifier.
So your not double amping.
Which sound card are we talking about?
 
 
 

asus xonar dx
 
 

 

[PurpleAngel]

Quote:

Asus Xonar DX

The Asus Xonar DX does not have a headphone amplifier, it has a "Speaker/line out" jack that you can plug your headphones into.
If it had a headphone amplifier, my Xonar DX would still be in my computer.
 
 

 

[EinZweiDrei]

Quote:

The Asus Xonar DX does not have a headphone amplifier, it has a "Speaker/line out" jack that you can plug your headphones into.
If it had a headphone amplifier, my Xonar DX would still be in my computer.
 
 

since it doesnt have a headphone amp. do i just feed the front out to my desktop headphone amp?
and should i set the sound card volume to max and adjust listening volume on my amp?
or do i adjust my amp on half and adjust listening volume on soundcard?

 

[PurpleAngel]

Quote:

Since it doesn't have a headphone amp. do i just feed the front out to my desktop headphone amp?
and should i set the sound card volume to max and adjust listening volume on my amp?
or do i adjust my amp on half and adjust listening volume on sound card?

Yes, front out to the Desktop amp.
Volume setting, not sure.
 
 
 

 

[skamp]

and should i set the sound card volume to max and adjust listening volume on my amp?

Pretty much. A line out is supposed to remain at a constant level. Set your desktop volume to max (or below max if it saturates for some reason) and adjust volume with your headphone amp.

 

[stv014]

Quote:

If it had a headphone amplifier, my Xonar DX would still be in my computer.

Actually, the front output does have some amplification, because the other channels are much worse. More precisely, it probably has a better op-amp on that output that can drive headphone loads with lower distortion. But it is hard to understand why they added the 100 Ohm serial resistors, without those it would be quite decent in fact (but not huge maximum power).
Regarding the volume setting, it can be safely set to 100% (at least that is definitely the case on Linux), there will be no clipping. The volume control is probably digital. At the maximum volume, the output level will be roughly 2 Vrms, which is the standard for CD players.
 

 

[PurpleAngel]

Quote:

Actually, the front output does have some amplification, because the other channels are much worse. More precisely, it probably has a better op-amp on that output that can drive headphone loads with lower distortion. But it is hard to understand why they added the 100 Ohm serial resistors, without those it would be quite decent in fact (but not huge maximum power).
Regarding the volume setting, it can be safely set to 100% (at least that is definitely the case on Linux), there will be no clipping. The volume control is probably digital. At the maximum volume, the output level will be roughly 2 Vrms, which is the standard for CD players.

Rollar said he saw a white paper somewhere that showed that the Xonar DX had a headphone amplifier, but it is kept undocumented because Asus did not want to it to affect Essence sales and the headphone amplifier is controlled by some DLL file.
But I can't find any of this info anywhere, but I'm still leaning towards that the Xonar DX does not have a true headphone amplifier.
The DG which has a very basic headphone amplifier, powers headphones better then the DX.
I have a feeling Asus does cheap "hacks" (100 Ohm resistors) to keep the noise level down, but I'm far from a sound card engineer.
 
 
 

 

[stv014]

Quote:

Originally Posted by PurpleAngel /img/forum/go_quote.gif
 
I have a feeling Asus does cheap "hacks" (100 Ohm resistors) to keep the noise level down

Maybe (as a side effect of reducing the overall volume with low impedance headphones, which could even be the main purpose), but the card does not have high noise in the first place. It could be a simple protection against short circuits, and reactive loads that could cause stability problems, but the resistors do have an effect on the sound quality with many headphones. They even added 75 Ohm resistors to the headphone output of the Realtek chip on my motherboard, which originally has an output impedance of only 2 Ohms