Quick Gainclone Check

[matt09]

I've managed to get these boards made up for free, just wanted to make sure everything looked fine before I begin the soldering. How will those caps fair, I got them for free but there just the standard rather than high quality.

[AndrewT]

Hi,
caps look OK,
Make doubly sure that the electrolytic caps are inserted the correct way round.
Measure the voltage across each electro to finally ensure that the circuit board is correct as well.

That circuit board looks like the drilling jig is out of registration with the copper traces. The holes do not align. Going to make soldering difficult for the worst mis-aligned holes.

[matt09]

Hi,

Thanks for the reply, I see what you mean about the holes out of place, but in actual fact all the components seem to fit in just fine.

One question I do have is how well will it work without some sort of preamp when the input will be from an output of a mixer desk - i.e. low level output. I am guessing the input gain will have to be set high, but will this lead to a little audable hiss?

[AndrewT]

Hi,
I would guess the chipamp maxoutput to noise ratio will be close to -100db or at worst -96dbA.

With this level of amplifier noise, I suspect the mixer desk will be much noisier.

A good discrete will approach or even exceed -120db, if you need much lower noise levels.

For mixing duty you may need to be quite critical, i.e. low noise, low distortion and revealing speakers (not=nice sounding).

[matt09]

Thanks, I forgot the fact that most hiss is generated from pre amps rather than the power amps themselves, sounds perfect as it was only a bit of fun mixing, nothing too serious with visaton drivers which I know aren't reference in any case.