Both - it's very common in power supply units, but these are the only PSUs sitting on my my desk so quite audible when the ambient noise is low.Does the coil whine come from the A30 pro or the D30 pro (or both)? This might end being a dealbreaker for a lot of people.
FWIW, the whine in my D30Pro is a bit better than my A30Pro, and unlike the PSU in my PC, the whine is very high pitched ringing, like very mild tinnitus.I have 2x A50, 1x A50s, 2x D50s and 1x D70. The D70 PSU (internal) is dead silent, both of the D50s' are powered by 10$ worth cell phone chargers, also dead silent, but all three original PSUs of the A50s and A50 whine big deal when the devices are turned off. So I replaced them with some third party 15V AC-DC PSUs that are silent. I really don't like this whining noise issue with A30Pro, it would probably drive me crazy.
Erm, yes, looks like it. He says "Pre-amp balanced out" while it is in fact a TRS passthrough with no amplification stage.
"DAC mode" versus variable volume mode.
@amirm himself said that he never reviews prototypes of productsI already mentioned why i think thats a bad idea.
1. No way the amp Amir got was a release candidate, but a prototype.
2. Free marketing and hype by Amir for a product which is not ready yet.
3. Preorders are a evil thing and have no advantage at all for the customer
I wouldn't say "on sale"A30 Pro on sale at Drop.com and of course Drop posts pictures of the A90 on the product page