TOA Mic preamp connection.

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I have a couple of these taking up space in my closet and just happen to be in desparate need of a couple of preamps. I am not certain to to connect this outside Of TOA equipment. I'd like try this standalone. running in to +4 balanced line in.
 

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Looks like you need a 24v PSU possibly to get it running. If I'm thinking of the same modules they fit in a metal box that has a PCB bus board on the back. On mine the power supply and ins/outs are labelled on the PCB.

There are about 6 modules in the box. Inside each module is a pretty bog standard preamp, EG an OP amp fed from an IP tfmr. I think the opamp's run off 15v, so the 24v is dropped with resistors.

So to use them outside of TOA amp you need a decent PSU, I used a wall wart regulated supply, then either put the box in a bigger box and connect the OP's to 1/4" sockets or just solder 1/4" or whatever cables direct to the PCB.

Some pics of the actual modules would help.

Hope that helps, Andy.
 
With a single +24 supply, I doubt they drop it to 15. They leave it at +24 and ground the negative side of the IC, then set a 12v reference. Running op amps on a single supply is nothing new.

TOA would probably send you the actual schematics of whatever uses them, including the modules themselves.
 
"With a single +24 supply, I doubt they drop it to 15" Probably right, my memory might be playing me false; in the 906A preamp they do use big droppers and simple zener "regulation". The TOA website has lot's of schematics and manual's, I got mine there. As you see the module connections are pretty simple.

Andy.
 

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Toa makes a model 900 series II mixer which can be bought used for very little money. The modules slide into the back of the unit. I used them for over 25 years in conjunction with other equipment and they never let me down.

The same modules you have shown will also work in the TOA powered mixers the A903 II, A906 II, A912 II and A924 II in addition to any other Toa mixer or powered mixer or the series I (silver faced stuff).
 
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