All the wall outlet mfg's that you mention should be better than standard as should be the hospital grade outlets you now have.
One recommendation would be to seperate your preamp from the digital source. Digital has a way of injecting much AC noise back into the line and hence it is transfered to the pre.
If your amp are not drawing large amounts of current, perhaps you could try sharing the amps on one dedicated line and put your preamp on the other dedicated line. Even if they do draw large amounts of current, it would be an interesting experiment. You should only lose the macro-dynamics or dynamic headroom with such a move.
It would be interesting to know the results. I'm guessing this change should provide you better results than upgrading from a hospital grade outlet to another.
-IMO
One recommendation would be to seperate your preamp from the digital source. Digital has a way of injecting much AC noise back into the line and hence it is transfered to the pre.
If your amp are not drawing large amounts of current, perhaps you could try sharing the amps on one dedicated line and put your preamp on the other dedicated line. Even if they do draw large amounts of current, it would be an interesting experiment. You should only lose the macro-dynamics or dynamic headroom with such a move.
It would be interesting to know the results. I'm guessing this change should provide you better results than upgrading from a hospital grade outlet to another.
-IMO