Joule 150A MKII versus Atma-sphere Preamps

I question how much difference you would hear running the Atma amp balanced versus unbalanced, although there would definitely be less noise, hum and hiss if you ran balanced. The tonality would not change appreciably, IMO.

I run an Atma-Sphere MP-1 preamp balanced with Pass Labs amps and the combo is very, very quiet.

I do think it is the raison d'etre, but I'm not sure I could hear a difference based on the "quieter" potential of balanced operation. My system is pretty darn quiet. My quandry is that I don't want to own two preamps if I don't have to. I notice that many reviews of the Atma amps are actually using single-ended preamps, which makes me think it is fine, on the other hand you hear about the special "synergy" between the Atma pres and amps. I guess there is really only way to find out....

As I understand it, the basis for balanced designs comes from studio equipment. Unlike home use where 1-2 meters is typical for interconnect, studios often run 10-30 meters so noise rejection becomes critical. So balanced may measure lower noise, even in a home system, but is it audible? I wish someone would run a reliable test on this.

Another point, a few years ago I ask Jud about a balanced version of the Joule preamp. He said to make it truly balanced would require another gain stage and he did not believe that would be worthwhile (increased complexity in the circuit). He also mentioned the unlikelihood of noise with good quality interconnects of moderate length.

04-26-08: Pryso
So balanced may measure lower noise, even in a home system, but is it audible?

When I have experimented with gear that offered both balanced and single ended operation, I can say without hesitation that the balanced option was always audibly quieter.

I thought the goal of "balanced" cables was to keep the shield separate from the "-" wire. In many RCA's the shield is connected to the "-" so that the noise collected by the shield may become a part of the amplified signal. Doesn't a "balanced" cable drain the noise collected by the drain wire and connect it directly to chassis earth ground, bypassing the "-" wire, hence never giving it the opportunity to pollute the amplifed signal. Am I misunderstanding this?