I just received my new Crown XLS 1000 DriveCore Class D pro amp. You can find more info at crown's web site here:http://www.crownaudio.com/amp_htm/xls_drivecore.htm
These are very lightweight and very efficient amps because of their Class D operation. My XLS is 9lbs. I am also using a Panasonic BX500 Receiver which is also a class D amp that uses similar TI chips as the crown amp in the rest of my setup.
I am using the Crown XLS 1000 to power my dual HSU TN1220HO passive subwoofers. I am also using a HSU Bass Optimizer which is required to provide the proper EQ of the HSU passive sub when used with a non-HSU amplifier. Previously I drove my TN1220's with a used Parasound HCA-1000A 2 channel amp. I also have a BFD1124 PEQ in the signal path.
The short take, is that I am very happy with the new amp. I feel that the Crown is providing better control of the sub's woofer driver and giving tighter bass. In particular, I am using a great chinese drum album, "Poems of Thunder" Which has some great drum tracks for bass testing. With the crown amp I am hearing subtleties in the initial strike and post strike drum skin vibration I had not heard clearly before.
Poems of Thunder Album here:http://www.amazon.com/Poems-Thunder-...1435546&sr=1-2
Some further info:
1. The XLS 1000 is a pro amp. It does have a fan. However, I cannot hear the fan at all and I don't even believe that it has spun up with my home sound level listening.
2. Being a pro amp is wants higher level signal inputs. Even tho it does have RCA inputs (in addition to the pro XLR). I posted on the crown forum and verified that even on the RCA inputs it is looking for the +4dBu pro levels. (see here: http://www.crownaudio.com/forums/ind...showtopic=3759
) I have a HSU Bass Optimizer that also has a gain knob that can add +14dB to the LFE signal. So I can get enough gain thru the amp. But if your LFE signal is coming from a home -10dBV style consumer receiver you may have a problem.
3. I have setup the XLS with the following settings:
AMP Mode: Y input
Y input turned out to be an important feature. I have one LFE out on my reciever and I was splitting it into two with a RCA Y cable to drive both HSU subwoofers thru the two channels of the crown. However this seemed to lower my signal level and gave me problems getting enough gain thru the amp. Using the Crown built in Y function helped. I was able to feed just channel 1 and let the Crown Y function copy the signal to Channel 2. Even with the Y Mode, I can use the two crown channel gain knobs separately to balance between my two HSU's.
FILTER: LOW PASS
I am only using the amp to power a subwoofer. My receiver is already crossing the LFE signal at 80hz. I initially was using the filter in BYPASS (disabled) mode. However I was getting some higher frequency noise (very low volume, only could hear if you put your ear to the speaker during pauses in the music). By engaging the LOW PASS filter I now have dead silence at my subwoofers during music pauses.
4. I have an Entech WB powerline noise analyzer. I also use quietline noise shunt devices as well as Powervar isolation transformers for cleaning up or isolating powerline noise in my home. I previously plugged my Parasound HCA1000 directly into the wall since it was one of the high power draw devices in my system. I used the Entech analyzer to compare the parasound and crown noise-wise. The parasound did not add a appreciable amount of noise to my powerline. However, the crown with it's Class D and switching power supply does add noise to my power line. I use the powervar isolation transformers to separate the rest of my audio gear from the powergrid, so I have not noticed any negative impacts to my system. But with the entech I can definately measure the additional noise dumped into my home power lines from the crown. The crown itself is designed for pro environments and at least the marketing literature says that it can tolerate sags and dirty lines without issue.
I am purchasing a samson S Convert box that will allow me to increase my LFE RCA -10dBV signal to a pro XLR +4dBU signal. It is fairly cheap at less then $50. This box is discountinued but highly regarded and has been tested by a user on another forum to be fairly flat down to 10 hz. (see here: http://www.hometheatershack.com/foru...-cleanbox.html
) I am concerned since I am using the HSU bass optimizer at near it's max +14dB of gain I might get some distoration during loud bass heavy passages of music or movies. So I am hoping that the S Convert box will help adjust the signal gain in my path to the inputs of the amp. I will report back once I get the samson box in the mail.
Samson S Convert:http://www.samsontech.com/products/p...fm?prodID=1699