To amp or not to amp...

[bupton]

Hey all, I am in the process of getting my HT system beefed up a bit more and am looking at the possibility of adding a seperate amp to use on my primary rooms speakers. I am looking to use my Yamaha 2500 as a pre/pro and add a seven channel dedicated amp to push the speakers. Now here is my question (and I sure it will have some interesting responses). I have been looking at the Rotel amps, and I have a few friends here that swear by them, but I am also curious how the Adcom stuff stacks up against them. My brother has been using Adcoms for quite a while (two GFA 555s I think) and he loves them. Granted, his are mainly used for two channel music. Anyhow, I was just looking to get any feedback or suggestions from everyone out there. Thanks...

 

[PENG]

I am using an Adcom 555 with my 3805. I tried a Bryston 4BSST as well. The 555 held its own very well. The Adcom is probably good enough for receivers such as the Yamaha 2500, Denon & Pioneer equivalent. To get the benefits of a high end amp, you may need to upgrade your pre/pro as well.

 

[Snarl]

I use an Outlaw 755 Amp with my Denon, I'm very pleased with the results.

 

[DaveOCP]

To be honest, I'm really not that big a fan of either. Adcom is just barely a step up from the most basic receiver. The GFA-7807 may have almost twice the power of say, a Lexicon LX-7, but I'd take quality over quantity any day of the week. I've listened to Rotel's top of the line SSP and amp and was not all that impressed. It sounded about the same as maybe a $1500 receiver, not even on the level of say an Onkyo TX-NR1000, Elite 59TXi or Denon 5805.

I highly recommend pairing up a Parasound Halo A52 and A23 for seven channel amplification. They are gorgeous sounding John Curl MOSFET\JFET designs with the kind of specs you see on amps costing 4X as much. The A23 has an SNR of 112db, and a damping factor greater >800 (113db and >1000 for the A52). Their wattage rating even with all channels driven is very conservative. I have a Parasound HCA-1203A three channel amp rated at 140W x 3 @ 8ohms, and it can drive my fairly inefficient Mirage OM speakers to ear splitting levels without breaking a sweat. You certanly wont see 7 X 125W receivers coming in at 78lbs. and packing 2.5kVA toroid transformers.

 

[MacManNM]

I am using an Adcom 555 with my 3805. I tried a Bryston 3BSST as well. The 555 held its own very well. The Adcom is probably good enough for receivers such as the Yamaha 2500, Denon & Pioneer equivalent. To get the benefits of a high end amp, you may need to upgrade your pre/pro as well.

Huh?
Take a look at the measurements made on the 2500
http://www.audioholics.com/productreviews/avhardware/yamaharxv2500benchtestp2.php

You'd be hard pressed to find a pre/pro much better than that in any price range.

If you are looking for more power, a multi channel amp isn't going to do you much good. Your average outlet can provide 1800 watts of power. Take into account the efficiency of a normal class AB amplifier (60%) then divide by the 7 channels. Gives you 154 W/ch. This is the absolute most you could ever hope for, whereas if you get several 2 ch amps and plug them in to different outlets you could achieve 540 W/ch. In reality you would probably only need to use an amp on your mains. The Adcom is a good unit and will not sound any different than a Bryston, or Outlaw as long as they are all capable of driving the load.

 

[Doug917]

I use 2 Outlaw 755 amps with my 2500 and it rocks. You can't beat the value of the 755 amp.

 

[mtrycrafts]

If you are looking for more power, a multi channel amp isn't going to do you much good. Your average outlet can provide 1800 watts of power. Take into account the efficiency of a normal class AB amplifier (60%) then divide by the 7 channels. Gives you 154 W/ch. This is the absolute most you could ever hope for, whereas if you get several 2 ch amps and plug them in to different outlets you could achieve 540 W/ch. In reality you would probably only need to use an amp on your mains. The Adcom is a good unit and will not sound any different than a Bryston, or Outlaw as long as they are all capable of driving the load.

When was the last time you had such demand, or more, from all channels at the same instant? Which movie or music? Where so I can check it out.

 

[mtrycrafts]

Hey all, I am in the process of getting my HT system beefed up a bit more and am looking at the possibility of adding a seperate amp to use on my primary rooms speakers. I am looking to use my Yamaha 2500 as a pre/pro and add a seven channel dedicated amp to push the speakers. Now here is my question (and I sure it will have some interesting responses). I have been looking at the Rotel amps, and I have a few friends here that swear by them, but I am also curious how the Adcom stuff stacks up against them. My brother has been using Adcoms for quite a while (two GFA 555s I think) and he loves them. Granted, his are mainly used for two channel music. Anyhow, I was just looking to get any feedback or suggestions from everyone out there. Thanks...

What is it you don't like about what you have now?

 

[Buckeyefan 1]

When was the last time you had such demand, or more, from all channels at the same instant? Which movie or music? Where so I can check it out.

He may own 7 very inefficient electrostats, chose a 7 channel DSP stereo mode, with Sting's Field of Dreams.

 

[buckyg4]

Nothing wrong with the Yamaha for the surrounds. If I was you I would find a nice two channel power amp for the mains, or maybe a three channel if you are concerned about the center. Not sure what your budget it so its hard to give a reccomendation.

 

[MacManNM]

When was the last time you had such demand, or more, from all channels at the same instant? Which movie or music? Where so I can check it out.

Where is the "value added" in any of your comments?

 

[jaxvon]

Where is the "value added" in any of your comments?

I believe the answer is "none".

 

[DaveOCP]

With a sub\sat system, a power amp is probably not needed. If you're driving full range speakers though, you probably are not going to want something that drops to 50W or less per channel when asked to really work hard. It takes several times more wattage to achieve the same SPL at 20hz than it does at say 5khz.

 

[mtrycrafts]

Where is the "value added" in any of your comments?

Must be over your head then. Don't worry.

 

[bupton]

Hey Guys

Sorry I was away for so long. Things are busy for me right now that I am back in the states working the relief effort in the gulf. Dave was pretty close to being "dead on" with the fact that four of my five speakers in my home theatre are full range towers, and not the most effecient at that. On top of that, I do like to drive them fairly hard from time to time when I am watching movies and come only imagine it will be the same, if not more, once I get my hands on my new dvd player and can start doing multi channel audio. Another issue that I am looking at is the fact that I want to use the seperate amp to drive the speakers in my main room and use the 2500's on board amps to drive the speakers which I have in my bedroom, and maybe even the library (using the b channel) as well. So you see, there is a method (even if I am the only one who see's it) to my madness.

 

[jaxvon]

You might want to check out the new monoblocks from Outlaw. They're 200W into 8 ohms, 300W into 4 ohms. Plus, they have a nicer look (than the older model), unbalanced and balanced inputs, and trigger in/out so you can make them turn on by themselves. $325 each, but there's a discount for quantity purchases.

 

[WmAx]

You might want to check out the new monoblocks from Outlaw. They're 200W into 8 ohms, 300W into 4 ohms. Plus, they have a nicer look (than the older model), unbalanced and balanced inputs, and trigger in/out so you can make them turn on by themselves. $325 each, but there's a discount for quantity purchases.

Pfft! Behringer A500. Much better value. However, they are ugly as sin(at least to me) and I don't think they have a remote trigger.

-Chris