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Discussion Starter #1 (Edited)
I recently acquired a QSC DCA1622 amp second hand to use in my HT rig. The plan is to use one of the amp's channels for a 2 driver IB sub and the second channel to drive a sealed Tempest sub. Both subs will present a 4ohm load to the amp which specs 500W @4ohms. I've tested the Sealed Tempest on one of the channels on the Tempest and there's more than enough output so I have no doubt the IB will be happy on the other channel. However the test was done straight off the Sub-out from my receiver (don't yet know it's voltage output).

So my question relates to signal level matching. I bought a MiniDSP 2x4 (unbalanced) to use for sub EQ and such awhile back before I decided to go the pro amp route. I am now concerned that the max signal level from the Minidsp of only .9V will not be hot enough to drive the amp to full power. QSC states it needs 1.1V reach full power @4ohms and 1.2V @ 8ohms. You probably know Minidsp offer a "balanced" version that can output up to 4V depending on configuration and as far as I can tell will actually convert an unbalanced signal to balanced.

Would it be a wise idea to perhaps get the balanced version instead in this case? Or possibly use something like the Cleanbox Pro after the MiniDSP ?
 

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Sure, it looks like the miniDSP won’t pass enough voltage to drive your amp to max. But that’s only an issue if you need the maximum output from the amp. If you can get as much level as you need from your subs with the miniDSP that you have, then there’s no reason to get another one or a signal booster.

If you can’t get enough level, then a signal booster after the mini DSP will do the trick. But if you're coming up short at .9 volts, I doubt another .2 volts will provide enough extra power to get you from "not enough" bass to "more than enough." IOW, a more powerful amp may be in order.

Regards,
Wayne
 

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Not arguing with Wayne P., I just had to look up some detail on this topic and thought I would share it.

There is a gain jumper in the 2x4 that allows max input voltage settings of either 0.9V (rms) or 2.0V (rms). The max output voltage is 0.9V (rms) either way.

You would be "losing" 2.5 dB of your power due to signal level mismatch between the 2x4 and the power amp.
 

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Discussion Starter #4
Well it turns out that the amps I bought second hand had some pretty bad PCB burning. To replace the boards it would have been too cost prohibitive so I returned them.

I am now trying to decide which route to go on a different amp. I'm considering an inuke DSP amp which would eliminate the minidsp. Does anyone know if the inuke allows independent eq of the 2 channels or are they global?
 
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