"I've
owned a Q21800 for close to a year now, and must say it is a
fantastic amp for the money, and really only have a few dislikes
about it. First off, this is a really solid amplifier. It puts
out quite a bit of power for the price you will be paying for
it, and although I feel the max power rating is a bit harder to
believe, the RMS ratings (I feel) are pretty accurate. Wiring is
simple, with power and ground terminals accepting up to 4 gauge
wire, although I did have to take the little plate off of the
screws to fit the terminals I got. You must have a good sized
wire running to this amp with power and ground, as this amp
draws a lot of current. I recommend a capacitor of some sort to
back this amp up. The only bad thing about this amp is the
internal crossovers. This is a fantastic amp, but to get the
best quality sound from it, I feel it would be best to use an
external crossover. The only other thing I did not like was the
fact that it will only do 4 ohm mono. It isn't really a huge
qualm of mine, but I have a Farenheit CK-12D wired in 2 ohms,
and would really like to see it with more power. Not a huge deal
in my opinion.
Bottom line: Fantastic amplifier for the money, poor crossover,
and you must have good quality RCA's running to this, as there
may be a little distortion when you put the Bass Boost on."