ah, nevermind, had a reply from the Aus distributor and nudging them:
(info about CDQ)
a) Did you guys end up having and subsequently fixing ES sabre chip problems with I2S and USB? Do units purchased through distributors need to be sent back to UK to reflash and fix it? (there are indications that there are problems with the ES chips on various forums and that people had to send their units back to UK to fix them)
Quote:
Sabre is not without its quirks, however there was never a problem with I2S and Sabre itself has nothing to do with USB. Either way, bugs in Sabre cannot be fixed by software as they are in hard silicon and there is no will from ESS to issue new chips with fixes for common ailments.
**Since the release we have not a had a issue with the Sabre chips here in Australia. There will be future firmware updates available at a price TBD.
eeeeh? (bolded bit) I was under an impression they're free in UK and judging by the firmware update log posted on head-fi (attached) not infrequent and sometimes fix important issues/sometimes add features...
b) What sort of a HP amp circuit is used and what are the power outputs at different impedances, along with THD+N? (and whatever happened to including that in the manual?)
Quote:
Headphone amp has the exact same specifications as analogue preamp - it is the same output that is relay switched either to headphone jack or rear panel outputs. It is a discrete Class A stage that starts to current limit past 100mA. The stage drives 50 Ohm loads without detectable rise in THD, so the THD+N figure is essentially the unbalanced SNR figure. Maximum voltage swing is about 5Vrms. Maximum power will be limited by current limit for low impedance phones and by voltage swing on high impedance ones - easy to work out for specific impedance multiplying voltage by current.
and a confirmation that the unit's USB is not galvanically isolated.
Edited by svyr - 6/2/11 at 4:25pm
. Pity, I liked the selectable digital filter as well.
?
