1 May
2012
1 May
'12
11:52 a.m.
On Apr 26, 2012, at 2:46 PM, Tony Duell wrote:
I do wonder why modern domestic audio equipment
doesn't have balanced
inputs nad outputs. Doing so would have added a lot of complexity when
using vavles,, but with op-amps it's trivial. And that would be a serious
way to reduce common-mode effects (like earth loops).
But then I can;t expect Audiophools to understand engineering...
Certainly the stuff i use for recording does. But yes, it is
surprisingly uncommon, even in high-end equipment. I knew
someone who built their own headphone amp which was fully
differential all the way through until the output transistors.
THAT was a quiet amp. Differential inputs are all well and
good, but I've found that even with my setup, some GSM cell
phones can introduce noise in the internals which gets
propagated quite audibly (that biiiiiiiiiiip bip bip bip sound
comes from the RF power amp switching on and off at the TDMA
frequency and couples into audio amps quite well, I've found).
- Dave