DIY mixer

[O'Dubhain82]

Hi,

I was recently given a 100 volt line PA and would
like to adapt it to use as a backup for use in my
pub duo. We need 2 instrument inputs and 2 vocals.

The PA has a panel which houses a row of 6 cards,
each with xlr inputs and 3xtone control and a volume
knob.

Is there a simple way to convert this panel into a mixer
with a master volume and line level inputs?

Any thoughts appreciated.

[BogeyBass]

Yes its very simple.

Would be about a 100 bucks for this adapter

[dhsierra1]

If you're not afraid of a little DIY here's a way to sum all those very easily, Figure 2 could be your answer. This guy has some very nice projects, you could even snag the PC board from him. A few colleagues of mine have used his stuff before and he's very reliable and good to work with.


Universal Preamp/ Mixer

The op amp he specs is about as common as they come so nothing exotic, expensive, or difficult here. Good luck

[dhsierra1]

Originally Posted by BogeyBass

Yes its very simple.

Would be about a 100 bucks for this adapter

actually just a passive 6 channel line mixer would be all he needs since he's already got the inputs, preamp stage, and eq for 6 individual channels, he just needs to sum them so you're on the right track. Check Parts Express for non-powered mixers, they'll be under US$ 100 easily.

[Passinwind]

Originally Posted by dhsierra1

If you're not afraid of a little DIY here's a way to sum all those very easily, Figure 2 could be your answer. This guy has some very nice projects, you could even snag the PC board from him. A few colleagues of mine have used his stuff before and he's very reliable and good to work with.


Universal Preamp/ Mixer

The op amp he specs is about as common as they come so nothing exotic, expensive, or difficult here. Good luck

It works much better with even a modest opamp upgrade though. OPA 2134 or OPA2132 both work really well in it, in my experience.

To the OP: don't forget that you will need line transformers for your PA cabs too.

[dhsierra1]

Originally Posted by Passinwind

It works much better with even a modest opamp upgrade though. OPA 2134 or OPA2132 both work really well in it, in my experience.

To the OP: don't forget that you will need line transformers for your PA cabs too.

+1 on both comments

[O'Dubhain82]

Yes its very simple.
Would be about a 100 bucks for this adapter

I think you may be right. It does look very good.
Appreciate the replies,

[dhsierra1]

Originally Posted by O'Dubhain82

Yes its very simple.
Would be about a 100 bucks for this adapter

I think you may be right. It does look very good.
Appreciate the replies,

the problem w/the XENYX mixer suggestion is that it too has a preamp stage in it so when you plug in those cards you'll have gain staging issues big time. Passive 6 input line mixer is the way to go, plus you'll need a transformer for the speakers as mentioned by Passinwind (who I believe is a soundman and thus knows this stuff more than I do).

[Passinwind]

Originally Posted by O'Dubhain82

I was recently given a 100 volt line PA

What make and model is it? I used to do field service on a lot of that stuff, a zillion years ago.