Clean and solid performer
I'm using the Peavey IPR DSP 1600 to drive a pair of DIY speakers with a nominal 4 ohm load. Input has been from a laptop (both headphone jack and Xenix USB mixer) and from an iPhone. These devices have slightly lower output levels than the maximum input of the amp. This results in a max output of around 250-300 watts into each speaker when attenuation is set at 0 dB. These are measured values, so the amp is delivering on its rated sensitivity. This level is actually a great match for the speakers as the woofers hit their XMax at around 300 watts in the 10-30 Hz range.
With all EQ bypassed the response is essentially flat. The DSP functions provide enough parametric equalization to adjust response based on the room and speaker placement. It would be nice to be able to set the filters using a PC - the manual process takes time and on the road this may not be useful (keep the response flat and filter from the control board). In the home it is set and forget, so a very nice feature.
The fan on this amp is not audible during operation unless you are in a really dead room and aren't playing any sounds. I do hear the fan during shutdown as it spins up to exhaust any latent heat. I've yet to feel any warmth coming out of the amp, even after a couple of hours of heavy techno with the DDT light flickering once in a while.
No pops/thuds when turning it on/off.
My biggest complaint is that I cannot set a High Pass Filter at a low enough frequency. If I could set one in the high teens or low 20's, I could put another 30-50 watts into my speakers w/o exceeding the max excursion of the woofers. IIRC the lowest value for an HPF is in the 30's and that would take away too much of the lower bass.
In the minor complaint side, this unit could easily be a 1U instead of a 2U. There just isn't much inside. Also, the ears on the front are excessively large and could use a redesign.