How do I do that? Do I need some special instruments to do this?
Or do I just connect some mic cable in mic input which I already have.[/QUOTE]
Yes, will need a 150 Ohm metal film resistor across Pin 2 & 3, and a 20KHz filter..To measure accurately..
I put up a test a while back for another reason but will show noise level expected from a GOOD Mic pre with a -128.5dB EIN, ISA One has -126dB if i recall... Mic pre Noise test with/with out mic.