ABX Switching Box for Phono + Line Preamps


2004-01-11 11:01 pm

So as to be sure that no prejudice is being exerted when I conduct listening tests, I’d like to get an ABX box made. If the ABX box is suitable for blind testing - all the better.

The box will be needed to compare Phono Preamps against one another, and Line Preamps against one another.

Does anyone have a schematic they can link to that shows such a device? I reckon I could ‘design’ a pretty good switching box for Line Preamps (using relay switching), but I’m nervous about using the right kind of relays for low-level signal switching.

Google turns up this link:


Any suggestions would be gratefully received. Thanks in advance.