Polygonhell
100+ Head-Fier
My understanding is that the AIC has a voltage divider (2 resistors per channel) on the headphone output, rather than just running the signal to it. This does a couple of things, it’ll change output impedance a bit but it’s probably not relevant given it’s a SS output stage, but it also attenuates the output, which will reduce the noise floor. I only had one here briefly and didn’t test the speaker taps, but I’m told that with very sensitive headphones like the Utopia you can hear the noise floor though the speaker taps but not through the headphone jack.I have heard some folks agree and others disagree about using the speaker taps on the AIC-10. Could it be a cable difference?
I use a similar “trick” in the amps I build for myself, a switched attenuator to give more room on the volume knob and make placement/ shielding of the power transformers a bit less critical when listening to the MySphere or Utopia.
The resistors are IME audible but it’s very subtle, on my amps, I can relatively easy volume match and I have a switch to bypass it, without the divider, there is a touch more impact, but it’s really subtle.
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