Adding an input switcher


2010-09-27 9:29 pm
I have a pre-amp with only two inputs, which are switched via toggle switch. I am installing two more inputs, and I can go one of two ways on the new switches for the two new inputs. One is to just install a Grayhill 4 way input selector, and the other is to install a the ABBRES system from Parts Connexion .... This is an electronic switching system that is switched vi remote control. My concern is losing sound quality by going through the ABBRES system .... Any thoughts on this ?



2005-03-07 12:00 pm
I have designed with Fabio Restivo this system to be trasparent.

the design points were the following two:

1. no THD added.

2. negligible level of electromagnetic interference in the signal path.

regarding the point 1, the audio signal only throughs relaies with gold plated contacts, so there is no THD added.

Regarding the point 2, there is a negligible level of electromagnetic interference.
Merely, the digital section produces a negligible level of electromagnetic interference because its microprocessor has a very low quiescent current so it produces a very low RF noise (less quiescent current less RF noise).

Pier Paolo
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