After thinking plate amps were the only answer to drive a subwoofer, this forum guided my thought process to change. A few months back, I pulled the trigger and ordered the Nady XA-1100 amp to drive a pair of subwoofers that I was building. The amp sat for well over a month waiting on those subs - until a few days ago when I constructed something to use the amp with.
The numbers (power):
- 2 x 550W @ 4 ohms
- 2 x 730W @ 2 ohms
- or, 1100W @ 4 ohms bridged mono
Connectivity:
- Parallel balanced XLR and 1/4" TRS inputs
- Binding post outputs
Weight / Size:
- Consumes 2 rack spaces (pro audio configuration)
- 19" wide, 15.7" deep and 3.5" high
- 41.8 Lbs.
The amp arrived nicely packed - double-boxed by Nady and shipped by Musicians Friend. I pulled it out of the box and thought it felt like a nice, solid brick.
The amp was relatively simple to connect - once I made a trip to my local Radio Shack to procure the proper connectors. It's such a solid piece, I have no fear of breaking anything.
I was aware of the specs when I purchased it which included a "soft" power-on feature which virtually eliminated sny speaker thump during this process. I was very happy to see this feature worked nicely. After a brief calibration, I was on my way. In no way did I push this amp for all it was worth because the connectivity was made at 1:00 A.M. and I didn't want to wake the family - or, the neighbors. Instantly, my little 10", 8 Ohm sub came to life. After doing some re-calibration and allowing the driver to break in a bit, I felt really good about the purchase of this amp.
Now, for the bad news - well, not so bad.

- The dual 2-speed cooling fans make the amp sound like a jet. Well, not quite as bad as a jet taking off, but still quite loud. Fortunately, the fans are standard 80MM, 12 Volt fans. I'm going to hit up some of my computer supply places to pick up a pair of nice, quiet fans to replace them with. The connectors off the fans are standard 2-pin Molex connectors, so the replacement will be quite easy - once I get the red locking glue off the threads. Actually, last evening, I disconnected the fans and used the amp for a while. I loved not hearing the fans and the amp didn't get any hotter than my H/K AVR-7200. If I were to run this amp permanently without cooling fans, I think some additional holes on the sides of the case adjacent to the heat sinks would be in order, though.
On to the pictures. The picture of the open case shows the massive torroidal transformer which weighs probably 25 Lbs. by itself. Also, if you look at the binding post connectors, you can see heavy brass-colored supports which make these connectors very solid. Finally, I included a picture of one of the turbo fans so you can see the source of the noise with this amp.
When I purchased this amp, it was $249 + shipping from Musicians Friend. However, I realize that the price has gone up a bit - to $279.00. However, I still think it's a geat buy for all the power you can buy for that price.
Enjoy!
