This amp sounds great and the EQ, crossover and other features are really useful. The problem is that it makes a knocking/clicking noise when it turns on

This is what my system needed. With my two home made sub enclosures. Now they get all the power to drive them. The sound is very clean and blends in great with my 200w mono blocks. Set at 80hz to 100hz with a little over half gain was it and done. It's good they give so ways to control the output. Well, for those who really need it. Otherwise keeping it simple works the best for most. This amp is not complicated unless your trying to do to much with it. The "less is more" formula works just fine. Look I'm listening to it right now and it sounds great with very little set up. The only thing to complain about is the LED light could of had a dimmer installed. But a easy fix was with a small drop of nail polish from wife. Now it's not so bright anymore. Overall I am real happy and believe it to be a very good amp.

I purchased to power two buttkicker lfes but soon discovered this was not possible. The problem is despite this amp having two speaker terminals, internally they are wired as parallel so if you run each terminal to a 4ohm buttkicker you end up with 2 ohms of resistance which isn't enough. And if you run them in series you get 8 ohms which reduces the total power output of the amp to 450 watts or 225 per buttkicker and you need at least 400 -1500. Good news is the amp has enough adjustments that it makes tuning the one kicker possible and I underestimated how much 1000 watts to a single kicker would suffice. I wish the documentation had been clearer so I had realized it couldn't handle two 4ohm subs @ 1000 watts but for the price I'll probably just end up buying a second one too. Also as other reviewers have stated the blue light is obnoxious but for me it's a non issue with it being setup in the back of my theater and not near the screen.

My Buttkicker amp died. I needed a replacement. The Buttkicker company no longer makes amps but recommended this one. All the features (low pass filter, high pass filter, EQ functions) work perfectly for any subwoofer, or in my case a Buttkicker which requires the exact same amp technology even though it is not a speaker. If you are not familiar with them, they are shakers for a couch or chair, and make the apparent sound level greater (while actually making no sound at all) by increasing the low frequency effects.
I have one Buttkicker LFE amp on each of four home theater chairs. Each requires "500-1500 amps" of amplifier. I bought two Dayton 1000 amplifiers to power the 4 Buttkicker LFEs and used a RCA splitter to divide the subwoofer signal to both. Works frigging awesome!
Only problem is the amplifiers have a ridiculously powerful power LED. With two amps, there is a blue sheen on the home theater screen 14' away that is obvious on dark scenes. Ridiculous. I put some black duct tape on some wax paper, then used a circle punch to cut out a circle for each amplifier. Peeled off the wax paper and stuck them over the power LEDs. Still plenty bright, no kidding. But at least it doesn't light up the room.
My only concern is that the cooling vents on the lower amplifier are right underneath the intake for the amplifier above. The legs are only like a centimeter tall. I am going to add something to lift the upper amp higher to assist with cooling. I have not measured the temperature in use, but think for Buttkicker amplifier it shouldn't be a big deal as the subwoofer soundtrack typically only triggers the Buttkickers like 1% of the time. Others have complained that these amps get super hot with music.
The Buttkickers let you shake the people instead of the house. I have dual SVS PB3000 subwoofers that can shake the house no problem. But turn them down a little, turn up the Dayton 1000 Buttkicker amps a little, and save your ears. The effect is the same or better and noone gets a headache. Wife acceptance factor improved. Now its like your subwoofer goes down to 1Hz even though it is 18Hz typically in real life. For example, the cannon broadsides in Master and Commander will have you crying for your momma and hiding behind the couch. The thunder at the beginning of Open Range is more dramatic than real life. And a hundred more examples.
When I first bought the Buttkickers (4 of them, one each for 4 home theater recliners) it came with a single 1000 watt amplifier, for 250 watts per Buttkicker LFE when the recommendation is 500-1500 watts per Buttkicker LFE. It was not impressive, more seemed kind of like annoying and I didn't use it often, as it didn't seem realistic, was more like you were being dragged down a gravel road. Now with twice the power with dual Dayton 1000 amps, and 500 watts per chair, the Buttkickers actually are much LESS noticeable. Or maybe it is the better crossover of the Dayton amps. It used to be they were on or off. Now they blend in more (ie more variable response) with what is happening on the screen which improves the whole experience.
My new Dayton amps have made a obvious improvement to my home theater. Highly recommended despite the ridiculously bright power LEDs. Wow!

This thing is built like a tank and provides very high fidelity bottom end, and a lot of power.
The parametric EQ is an excellent feature, as is the multiple turn-on options, with either auto-sense, 12v trigger, or manual.
It would be a solid 5 stars if it weren't for that nasty power on thump. They really should've designed a delay relay or another means to prevent this, especially at this price point.
But I'm keeping it for the fidelity, The Dayton Class AB/Class G Sub Amps really sound excellent. I have some of their plate amps too.