Using 2 amp modules from 1 SMPS

[MikeHunt79]

Right now, I'm using one of these:

http://cgi.ebay.co.uk/ws/eBayISAPI.d...m=230237619388

Powered by an SMPS from an old car amp which gives my +-24v.

Right now I'm only using the +24v line to power the above module, as the module only needs a single ended supply.

Now, I'm thinking about adding a 2nd module so I can do away with my passive crossover, and go fully active.

Now if I was to add a 2nd module, would it be best to power it using the same rail (+24v?) or use the other rail (-24V?). The only thing I can think of is there may be a problem as the 2 amp modules will be using the same audio GND, so there may be a 24v difference... I'm not sure really. I'm tempted to try hooking it up but I don't want anything to go up in smoke!

I know the SMPS is up to the job as I've had almost 10A out of it using car bulbs as load. There was some sag but it still stayed above 20v.

[djQUAN]

you can't use the -24V line as if you do, input signal to the second module will be referenced to -24V instead of AGND. you don't want that, trust me.

I think two amps can be powered from the + rail without any problems. not sure about the two modules interfering with each other due to switching freq's though. try it and see.

[MikeHunt79]

K, I'll hook 'em both up to the +24v rail, they're great modules for the money, and use very little power being class D.

FWIW, the SMPS is switching at 27KHz, but I've yet to hear any nasty things like switching noise.