How do Adcom power amps sound?


My system is : PSB Stratus Mini, Cambrdige AZUR 540a and a Toshiba 3950 ( unmodded) in a 20x20 room with the speakers placed about 6 feet apart and mostly listened to in the close range.

If you arent familiar with my speakers they are a pretty tough load, 4ohm at 86db.

My amp only puts out 40-50 watts into 8ohm and 65 into 4ohm, as you can tell its having trouble powering my speakers, so im considering buying a power amp for them.

Im on a pretty tight budget , and the Adcom power amps seem to be priced right, so im considering something like the GFA-555 ( 200 wpc 8ohm and 325ohm).

Does anyone have any experiance with this unit, or similiar Adcom units? How do they sound, would it be an upgrade, power and quality wise over my current cambridge amp?

Id probabaly use the cambrdige as a pre- amp untill i can afford something better.
Honestly, I would much rather listen to the Cambridge. The Adcom 555 is a somewhat forward and bright amplifier. In this price range, I much rather have a Rotel, a used Forte, a used Counterpoint, or even a Quad. Save your money before you buy a 555...

You may also want to look at Rotel and Parasound. You're right, you need more power and better current capability. You'll be glad you did. I'd opt for my suggestions over the Adcom. Cheers
Adcom amps get a bad rap . Some are in fact as the Kid correctly pointed out bright and edgy . Especially the 555 and 555 11 series . They do make good amps for passive sub enclosures . They are also bridgeable to 600 watts mono as well . Adcom made a grand leap with the 5800 and the amp was a distant cousin to their former line. It was sweeter and mated well with the excellent and reasonably priced 750 preamp and cd player which in my opinion still holds its own in the market. I still hava a 535 in a multi zone audio distribution system which is also a pretty smooth unit.
The Adcom GFA-5802 is a warm and sweet sounding amp from my experience. It also has outstanding vocal reproduction, and a great midrange, IMHO. It is a really great sounding amp in its price range, and is not hard or edgy at all. It is basically an all MOSFET design. It sort of reminds me of a tube amp in some respects.
It does match up extremely well with the Adcom GFP-750 preamp.
The only slight drawbacks that I heard from the 5802, in comparison to high dollar amps, is the bass isn't quite as tight, deep, or controlled, the sound is slightly slower and not as detailed, and the highs are VERY SLIGHTLY rolled-off.
Would I buy it again for a secondary system? OH YEAH!
I have the Adcom 5802 with the Stan Warren mods.
DaltonLanny your right what you said.
But with the mods, the bass becomes fast and tight.
I have had an Adcom GFA-555 since about 1991.? Sometime around 2000, I bought a used GFA-5503 (3 channel MOSFET) and compared it to the 555. The 555 sounds pretty bad in comparison! The mosfet design is much better! I would not recommend the GFA-555 unless you were going to use it bridged mono for a subwoofer amplifier. It would be a bargain for that at about $325. However, I WOULD recommend the GFA-5500 (2 channel MOSFET), for the used price of about $450, as a bargain. Of course, if you are willing to spend more, the 5802 would be even better. But then for that much money, there are probably alot of other good choices. (BTW, there is one up for auction right now.)

It is funny how the GFA-555 got such rave reviews when it was on the market and it actually isn't that great! I'm pretty sure it was a Stereophile Class B recommended component. Of course, I still have mine on my rear speakers. It won't die! It is well built and dependable!!
I have a 5400 w/ Stan Warren mods. I also owned a 555II and 545II. Go for the current models. The older series amps can sound bright/hard.
I own an Adcom 5300 and in comparison to my Plinius SA100 MKIII it was surprisingly not too bad with a fairly nice tonal balance and good power. Going back to the Plinius I went AHHHH!! and noticed it was way more refined and controlled but the moral is the Adcom held it's own for a $200 amp that is for sure, (driving Maggie 1.6s too).
I owned a 555 Mk II many moons ago....didn't realize how fatiguing it was until I bought a McCormack DNA .5...that was the start of my audio addiction...that friggin' McCormack!


Thanks for the input everyone , but i think i may just save up for awhile untill i can afford something like the Bryston 3bst. I want to get as much as an improvement as possible.
good idea!
FWIW for a lower priced amp I would consider NAC, they honor the music and have consistantly gotten good reviews...
Adcoms are good entry level gear. However, I agree with the comment about the McCormack. It's in a different league.
My new ( to me) Adcom 300 by 7 powers my B&W's just fine and solved a preponderance of problems. I am fairly new to high end audio, so take that into account. I have heard my same speakers on a McIntosh amp in a demo room and heard no difference. I am certain more seasoned ears would disagree, but for 1700.00 (slightly used)I do not think I am missing out on anything that would be audible (to me). What I did notice, like night and day, is that doubling the power made a slight difference in volume but a huge difference in overall sound quality.
how can I contact Mr. Warren/associates regarding a potential modification for my adcom gear? thanks
I agree with The Kid, Brainwater, Bufus.....

The Adcom GFA555 is just too bright. By "bright" I don't mean, "detailed"... two different things. The GFA555 Mk2 is a bit easier on the ears, though it's still noticeably edgier than a midrange/tweeter amp should be. That said, the original bipolar GFA555 is a rock solid *subwoofer* amp... highly detail and dynamic... just downright impressive.

I can't comment on later Adcoms since I haven't owned any.

The Forte Model 6 is the Class A-A/B version of the Model 4 (Class A) and it sounds nearly as good as the 4. The 6 provides a healthy 200x2 as opposed to the 4's 50x2. It sounds like you need the extra 6dB provided by the Model 6.

The Forte amps are simply amazing performers, regardless of price or build date. Current price for a very nice Model 6 or Model 4 is $400-700, depending on cosmetics and your luck :^)

Good LUCK!!
Great! The Adcom amps are excellent and there is excellent synergy with PSB Stratus mini. Get the mark II version of either the 545 II (100w/ch) or the 555 II (200w/ch). I had the 545 II and it is very powerful. I almost bought the same speakers but I was too cheap. I had an older Adcom pre also and it was the weak link. The latest 750 pre and cdp are great.

The 545 II can be gotten used for not much doe and if you want HT get 2 more for a cheap killer HT amp set up. The 545 II have a more manageable height and will fit on more racks with ease.

Also if you research it, mods are also available. A simple effective upgrade you can do is internal chassis dampening and a detachable power cord. It is easy to do because of space inside. Great amp! I have moved up the audiophile ladder since then but I still miss my 545II, and I owned it longer than any other piece of hi-fi gear.
I own a Musical Concepts modified Adcom 555. It has all Burr Browns,Black Diamond resisters and Teflon caps in the musical chain. It is wired with Van den Hul Silver and is dual mono. It has a cardas reference chord wired into it. It is a great match for my Vandersteen 3 Signatures and I have it paired with the Adcom The Gold 750. Every once in a while a Musical Concepts modified Adcom or Hafler amps shows up on E bay.
Just picked up a used Adcom 555 II. After listening for a few hours I can say that it sounds quite nice in my system.
It is being fed with a Dynaco Pas2 (modded and rebuilt),VPI HMW19 jr/Audioquest Pt6/Denon 103,driving Acoustat 2. Morrow cables throughout.

I have read many postings that this amp is bright and lacks refinement.Not Mine! The soundstage is wide,deep and precise.
Listening to Joni Mitchell portrays a sweetness that was ver surprising. Bass,,total control and with authority.
This thing is a keeper.