Believe it or not, if the bias is adjusted properly, the sound of this amplifier can be comparable to other high-end amplifiers that cost many times more. I compared it with the Plinius SA 103 class A amplifier, and found that the sound of the Adcom GFA 555 is even better, with solid, strong sound and deep bass, warm midrange, sweet high... Amazing Nelson Pass's design, a true legend classic amplifier.

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I let the Audyssey set up the speakers using 8 listening points. The sound in this system is incredible, from top to bottom. Grand, broad soundstage, 3-d midrange and highs, and the subs carry the lows with detail and tightness. The power seems limitless. I am moving the VR3s to the rear, and have Totem Forests on order for the front mains. J&M Windermere Towing

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Pops when turned on and off. My 85 dB Rogers Studio 3 compact monitors did not reveal all its immense potential with the Marantz. It was a good sounding amb but suitable only for easy speakers. South Bend Onsite Truck Repair

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My room is very small, and there was no need for a sub (for a bigger room, yes you will need a sub). But for $70, a nice bass presence and a little boost to Fight Club's airplane scene can't hurt. With these speakers, don't bother with cheap subs. It will be a waste of money. I'm saving my money up for an HSU. Sudbury Radiator Repair Service

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Picked up a orginal one an wasn't to sure about, had to replace inter fuses, but since then works like a champ! Only thing that I have that hold that watts is some cerwin vegas ls12, and it makes them come alive, especially at low volume.

No fancy lights, aka power meter.

power
attack
quiet running

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Having changed my Harmon Kardan AVR series receiver for a new Yamaha 5890, I thought I was taking advantage of new technology in modern receivers. I've been happy with the Yamaha until I decided (just for kicks) to revert my music listening to my old Adcom setup (pre H/K). WOW, I'm amazed how good the Adcom GFS 555 is compared to the amplification of my Yamaha (or even the H/K). The Adcom's, regardless of their age, still seem to best the new receivers I have for music. The attack of the music is impressive...as it the queitness of the components. I am running the GFS 555 amp, the 565 Preamp and the GDA 700 DAC. All three pair nicely together. I wouldnt give up my GFA 555 for any receiver in the sub 1000USD range. Now, my receiver are used for movies/TV only.

Using: Signet SL 266 mains

Very powerful! Exceptional clearity, smoothness and, definition. Cannot find a better amp especially for the money. If you cannot find an Adcom GFA-555 get an Adcom GFA-5500. It just sounds like a $10,000 amp.

Speaker Bindings holes are not large enough for 12 AWG speaker wire.

The Adcom Gfa-555 happens to be one of the smoothest and most detailed amps I've heard and that I own 2. They compliment but, yet sound identical to my 2 Denon POA-2400A's. The GFA-555 has a little difference in sound than the newer Adcom amps like the updated model the GFA-5500. The GFA-5500 seems to be a little brighter like, the highs and midranges are kind of screaming at you. Which I have found a way to resovle that matter. I tested a GFA-5500, hooked it up directly to my Denon AVR-3806 and hooked up my Definitive Technology BP-7002's to the amp just using what the average audio listener would use to hook up. Then I changed things as soon as I heard the brightness which, my GFA-555's never had but, I also had it hooked up with the accessories I used with the GFA-555 and that everyone, including audiophiles, multi-channel listeners and, Home Theater finatics should use. I took the Adcom GFA-5500 and disconnected it to start over. This is how I test all components I might keep and want to enhance my system. I took my Denon AVR-3806 with the AL24 Processors in it which has been rated as one of the best processors used as a processor and not a receiver and I would have to agree because I have used it both ways. Believe me a good amp will make a big difference compared to the amps in your receiver for better and stronger sound and definition. Anyway I took the Denon AVR-3806 was then hooked up to my Panamax 5500 Line Conditioner(very important to have for clean non-interference sound and picture) and Audioquest Interconnects which is also a must in having non interference free sound and picture also. I then wired up the speakers from the GFA 5500 with 12 AWG speaker wire. It also helped having my Denon DVD-2930CI multi format single disc player, also equiped with the AL24 Processor like the Denon AVR-3806. After I completely hooked up the Adcom GFA-5500 that way like my Adcom GFA-555's are the 5500 sounded a lot smoother and much more toned down with much more clearity. It was still just a shade and I mean a shade different in complete clearity and warmth than the GFA-555's sound. The GFA-5500 is still a great amp and you wouldn't notice the difference like I would since I'm used to listening to the 555. In this case the older amps are a little better and do have a little better sound than the new amps. The Adcom like all of the Adcoms but, the GFA555 can run down to very low impedences. They are almost identical to my 2 Denon POA-2400A's they have the same sound, clearity, and, smoothness as the Adcom GFA-555. If you can get your hands on one grab it. I gaurantee you will be very pleased.

Customer Service

Go to Adcom's website and check out prices and they do take trade ins to knock off money for an Adcom product. They are all good components.

Similar Products Used:

Adcom GFA5500
Denon POA-2400A
Denon AVR-3806
Denon DVD-2930CI
B&K ST 1400

great entry level to high end equipment,great power and clarity for the price,good looking well built equipment.

until i find what happend the weaknesses in these amps are very few to speak of as they always were great until that faithful moment.i would not personally buy adcom again due to the sudden large loss of some fine speakers.

adcom gfa-565 mono blocks were the main power of my system.they were used with a pair of klipschorns gfp 565 pre amp and adcom cd player and all m.i.t. high end wireing. the performance of these amps has always been incredible.tons of power to spare.last year the system started to get a buzz when it was turned on but played normaly.the buss got louder with time and one day the system at moderate level of output stoped producing sound.the instantainious distortion alert lights both lite bright for the first time ever.the rear speakers,a pair of klipsch forta,a rather expensive set of hardware showed a glowing in the woofers which quickly turned to flame.the mid and high components were uneffected by this.the bass section in the klipschorns blew the fuse in both speakers.highs uneffected as well. these amps disconnected from all and any components or speakers will set the lites glowing and fried a test speaker while trying to diagnose failure.these amps played flawless until that moment and happend to both at the same time.preamp tested ok with another amp.all wireing also tested ok. as for the quality and sound of these amps they are great. this misshap will be a discussion topic on other forum to see if this is an isolated case or what may have happened.

Similar Products Used:

adcom,klipsch,m.i.t,monster cable,and my new choice in electronis,krell.

great power, bridgeable. good build quality a true workhorse. I would love to get another one of these and run it bridged on a pair of 15 inch cerwin vegas. (not quality speakers but they will make your ears bleed they get so loud).

small power cord for the size of the capacitors. don't know if this is a weakness but the unit will play for 15-20 seconds after powering it off

I picked this up on a trash pile.the lady that owned it said it did not work and that her son had shorted it out. well, i asked if i could have it and she said yes. well to make a long story short i took the cover off and replaced all the fuses and low and behold it worked and worked amazingly well. this amp has great power and was in near mint conditon when i got it. i took the unit apart before replacing the fuses and cleaned it very well. for all intents and purposes i have a 200 watt per channel amp and all it cost me was 4 bucks worth of fuses.

Similar Products Used:

Onkyo, Pioneer, Klipsch

A very nice, well-built amp. A real bargain.

Emphasis of mid-bass

As a mid-fi amp, this thing is awesome. I've owned it since 1989-90? I feel this is a fairly neutral sounding amp with sufficient power reserve and an overall nice sound. Bass is not as tight and clean as the higher-end amps and it seems to emphasize mid-bass. Soundstage and dynamics are right on par or better for its pricerange. I've used this amp at full capacity for extened periods of time. I'm giving it an extra star for its no hastle, no repair longevity and value for the money.

Similar Products Used:

Parasound HCA-1000, Sunfire 300