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Posted By: JServ Question to M80 owners using seperate amps - 01/26/06 06:57 PM
First let me start of by saying that I have read a good bit about the advantages of using seperate amps, but what I am more curious is about what M80 owners think as far as the decision to use an seperate amp.

Here's my situation. I have a HK avr630 powering M80 fronts, QS4 rears, and a VP150 center as well as a hsu vtf-2. The HK is rated at 90 wpc in stereo and 75x7.

Lately, I have been thinking it would be very nice to get a nice 2 channel amp such as a rotel 1070 or similiar parasound amp, but I am not quite sure if it would be worth it. I mainly use the system for 2 channel music while studying (with or without a sub depending on the type of music), but also an occasional movie on the weekends. Here are some questions I have:

1. Do the facts that M80's are full range speakers and also a 4ohm speaker make them more likely to benefit from a high quality amplifier? I have read that a lot of HK owners run there fronts as "small" speakers to relieve stress on the amps, but I would much rather not do this.

2. Say I were to go the amp route...right now I'm looking at the Rotel 1070 which is rated at 130x2 wpc into 8 ohm speakers. They do not offer a 4ohm measurement on their site unfortunately. Do you think this would be too little of a power increase to justify the purchase. The next step up is the 1080 which is 200x2 wpc, which is probably around 300x2 at 4ohm.

3. Would using my HK 630 as a pre/pro for the mains affect the sound of surround sound movies. More specifically, I'm wondering if the mains connected to the amp would over power the center speaker still hooked to the internal receiver amp.

Just to put down some specs, here are the power output specs of the avr-630 vs the rotel 1070:

HK 630: 90 Watts per channel, 20Hz – 20kHz, @ <0.07% THD, both channels driven into 8 ohms

Rotel RB-1070: 130 watts per channel (20 Hz to 20 kHz @ 0.03% THD into 8 ohms)

First thing that jumps out is the lower distortion of the Rotel amp and that is definitely something that I feel I could appreciate.

Just finished up work study and off to class. Thanks for all your help guys. Everyone's willingness to help really makes this forum amazing.
The easiest way to tell if it makes a difference (I believe it does.) is to get one in your home for a trial.

Odessey and Outlaw both offer return guarantees. You could try Outlaw monoblocks (300 watt @ 4 ohm) or Odessey Stratos 2 channel to see if they make a difference.

If they make the difference you are looking for, you can return them if you'd rafther have a different brand. The return freight fees are worth the listen, IMHO.
HI JServ,

I have M80's powered by a separate amp. My receiver is an Outlaw 1050 which is conservatively rated at 65 watts. I switched to an Aragon 4004 that I picked up used on Audiogon for $600 (2 x 200w). It powers the M80's while the Outlaw drives the 3 other channels. The improvement in performance was very dramatic, at all listening levels. A lot of people say you will notice a difference only if you crank up the volume, but I found improvement even at relatively low levels.

I set the M80's to large, and I'm running a sub.

There is a difference in volume levels between the mains and all the other channels (center, surrounds). But this is easily adjusted into balance using the receiver. I'm sure your HK allows you to adjust the channel levels independently as well, so this shouldn't be a concern.

I think the Rotel 1070 will work well for what you are trying to do. Check Audiogon or other places for used equipment and save a bundle.
I have Rotel RB-1080 with my M60s. I switched from a Rotel 2 channel receiver (RX-1052) to Rotel RB-1070 and then to RB-1080. While I noticed a great improvement in the first upgrade, not as huge in the second one. I guess it would be more benefitial for you to get RB-1080 since you have M80s.
Posted By: Nat Re: Question to M80 owners using seperate amps - 01/27/06 02:43 AM
I started off with my Denon 3805 driving all speakers. I found that the sound was very good at high volumes and that there was high distortion at high volumes.

I then added a Sunfire stereo amp for the M80 only to improve sound at high volumes. What I found was that I got overall improvements in the volume of all channels (3805 being freed to drive the remaining channels). AND that the sound qualiy of the M80 (specially in stereo mode) becam really better. I noticed that they were very Open and that the imaging was improved. I Personally did not hear anything better than my setup at the moment.

I would advise you to go for separate amplification for the M80. Sunfire may not be the best choice but they were the only thing that was locally available. There is a high probability that I will move to Parasound in the near future.
I too am considering getting a separate amp for my M80s, and posted a similar question a few days ago. I have almost decided to get an Earthquake Cinenova Grande 5 channel amp (600 watts/channel at 4ohms).
For all of you guys thinking of adding an amp for your front LR speakers...check out this thread on AVS. I to am adding an amp. I just ordered my M80's today from the outlet and I can't wait!!! Anyhow, many AVSers are having great results with pro amps from the likes of Crown and QSC. They are a steal at <$350 compaired to the Parasounds of the world. Anyhow, this thread has me intrigued and I am going to try one. Here is the link:
http://www.avsforum.com/avs-vb/showthread.php?t=418666 . It is full of info and even blind tests that people were not able to tell them apart on.
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