I actually had the GFA 545 (Mk I). I had always lusted after Adcom gear since the late '80s, but when I finally got this unit in 2006 I was disappointed. I expected a fairly refined sound. What I got was cold, hard, sterile and steely. I felt like I had to get away from it every time I listened to it. I didn't help that I was using, at the time, Paradigm Mini Monitors V4. They exacerbated the steelyness with their titanium dome tweeter (just think I almost bought Focals... Yikes). I would think this unit would sound better with a pair of "New England" voiced speakers with their slightly rolled off top end. I'm talking original ARs, KLHs, Advents, NHTs, etc. So was it worth the money? Not in the least IMO. When I switched to tubes all was right with the world again and I've never looked back.

Built like a tank, Sounds great even after 15 years, Very powerful.

A little harsh on the high end. I'm trying different cables and speaker combinations.

This is a great amplifier. It's well built, powerful and very clean. You need to use high end cables and a good set of speakers to really enjoy it though. It seems to be a little harsh on the high end so soft dome tweaters are probably a better choice. It also has a soft pop during poweroff when the caps discharge. I called Adcom. They said this is normal. For $200.00 I'll live with the soft pop. Hi fi system for less than $1000.00. Can't complain!

Customer Service

none

Similar Products Used:

Adcom, QSC, Macintosh, DynaAudio, Bozak, PSB, Polk

Sound quality, build quality.

None.

I just bought this amp (actually a GFA-545, non MKll) after reading these reviews and several others and I must say that it certainly gets the job done. It is powerfull, much more powerful than the rated 100wpc indicates. I have my volume down by 75% over what my old 80wpc amp would be and still have the same volume level. The bass is tight and punchy and the soundstage is very full. I have more of a sense of being surrounded by the sound than I have ever heard before. I would compare this to the NAD 2400 power amp in terms of sound quality. Also, it is built like a tank.

Similar Products Used:

McIntosh, NAD, Carver

Power and low end

High end was very sterile and dry

This is for the original GFA-545 , not the Mk.II. To put it in a nutshell, I could not live with the 545 in stock form. The highs were unbearable, so I had Wavetrace Technologies (Clearwater, FL) modify the amp ($400) based on circuit designs by Stan Warren of the original PS Audio fame. After the mods, it's an amp I can live with forever! Sounds as good as the NEW A-20 (pure Class-A based on a Nelson Pass design) I later had powering the mids and highs on the Dahlquist DQ-20i's I had at the time with the Adcom powering the lows. Much better sound both highs and lows. The Adcom had been sitting dormant since I switched to active speakers (Paradigm Active 20's) in '99, but just brought'er out of retirement in my HT system. I'm using a Yamaha receiver with Klipsch speakers and wasn't happy with the sound...especially the highs with horn tweeters, so I popped the Adcom in using the preamp outs to power the front mains. All I can say is that 2 channel stereo is back! Now to find a 3ch amp, or go with a 5ch and be done with it. I really can't reccomend the original 545 due to the sterile highs, unless you're using it in a bi-amp configuration powering woofers, some really laid back speakers, or have it modded.

Neutral, clean sound. Muscular, can drive 4 ohm speakers with ease.

Nothing

I bought this product from a seller on ebay. It is connected to a pair of Kef C35s and a 30B subwoofer. The Pre-Amp is an Adcom GTP500II. I have not noticed the brightness that everyone is talking about in their reviews. So far, this combination sounds smooth and warm. I can listen to this system for hours at a time. It's not edgy like my Sony ES receiver.

The speakers have more to do with the sound. But I do notice the difference between this Adcom combination, the Sony ES receiver, and a Harman-Kardon integrated amplifier on the same set of speakers. To me, the Sony and the HK are more punchy and sounds exaggerated compared to the Adcom. At low listening levels, the loudness compensation of the Sony and the HK have a more pronounced effect. The Adcom, having more power and current, can drive the 4 ohm speakers with a little more authority. The sound is also much cleaner at higher volumes. The imaging is much better. I can't really attribute all of the difference to the amplifier since the pre-amp is also in the signal path. One thing I can say though is that this amplifier puts out very clean sound.

I have always liked the looks of Adcom components. They've got a modern, understated design to them. The quality and craftsmanship are very good on this Amplifier.

I want to clarify that the purchase price above is for the amplifier only. I already had the pre-amplifier when I bought the amp.

Customer Service

I have not had to call Adcom for this unit. I have called them before about my Pre-Amp and they always answered my e-mails. In my opinion, they have good service.

Similar Products Used:

Sony ES Receiver
Harman-Kardon Integrated Amp (PM 635)

Great Hi End Sound for a budget price

None

I've owned and just recently bought again! This is an excellent amplifier. I had and reviewed the original 545 and now I have 2 MkII's. This the best amplifier for the money. Open, sweet and detailed. This amp could drive the some of the hardest loads. Planars, Ribbons etc. I had and still have many speakers that go down to 4 ohms. Not a problem with this amp. Very clean and neutral and not as bright as many would think. Bass is tight and authoritative. Highs are extended airy and free from grain. ITS A MUST TRY FOR THOSE GETTING INTO HIGH END AUDIO. I'm in the trade and this is one of the best buys you can get and is readily available. Tried many vintages rivaling the price and performance but could be as rare as hens teeth at the time of this reading. These are the Quad 405.2 CLass A design and the the Sumo 9 Class A. Yes the performance does rival many of the Class A designs. This amp is simply supurb. I also have the GFA555Mk2 it's highly rated big brother and I still prefer the 545. Smoother highs, grainless performance and more liquid. The Hafler DH220 sounds a bit more relaxed but has a tendency to sound veiled. The adcom has a more elegant hi-end sound.

Similar Products Used:

PSE Dual Mono, Aragon 8008ST, Acurus, Quad 405.2, Hafler DH 220, Adcom GFA 555Mk2 etc. etc.

Mellow highs (if you prefer it), very tight bass reproduction, PRICE, sounds like a tube amp, build quality is amazing, you have to own it to believe it

Faded mids and dark highs

The GFA-545II amplifier is miles above anything in its price range. It directly competes with units costing thousands more. In an email, an Adcom user, Rona Wells, stated that "Nelson Pass of Threshold and Pass Labs fame, designed the circuitry and the 500 series amps are generally referred to as one of his great achievements." This amplifier is one of the most solid amplifier I've ever used. It is very heavy and built like a tank. It outputs true 100watts. If you have never experience true 100 watts, you're in for a real treat: it's LOUD. Upon initial audition, I found the GFA-545II to create a very transparent soundstage with depth and a LIVE feel. On Howard Shore's "The Score" soundtrack, the highs are produced with good clarity but are rounded off very smoothly. The highs are delicate and not harsh like many solid-state amps. Where this amplifier shines is in its bass output. It handles low frequencies very well. The bass amplification is very tight, with no boominess common to solid-state amps. This amp bends more towards the sound of a tube-amp rather than a solid-state device. The sound it produces is not harsh at all, yet at the same time, the subtle nuances of a symphonic orchestra CAN be heard. I would only say that although the highs are not as harsh, they, at times, can be muted. Also, I would say the midrange frequencies are not as good as some other amps I've tested. Overall, I would strongly recommend this amp to anybody.

Similar Products Used:

Bryston 4B, Adcom GFA-555II, Mark Levinson No. 431 (tested! amazing! not owned-too expensive for me :()

power headroom neutrality .. not a krell but not 2000 either .. can find on ebay for 225 to 250 and will blow anything new away up to 1000

none at $$$

i am reviewing the 545 origianl.. much more tubelike and dynamic than the II ... some say the II handles lower impedances better .. well i push tannoy saturn 8 's 6 ohm and the 545 rocks to no end .. very dynamic and powerful with a soft top end .. not the harsh i feel from the II .. the II is still a great amp but the II is more neutral ... still the 545 555 etc are lightyears better than there followers the 5400 5500 etc .. they lost the qualities that but adcom on the map ,, hence the uprising of ATI and Outlaw .. i am a avid ATI fan ..

Similar Products Used:

krell ..ati .. outlaw .. carver ..harman .. audiosource (fluke)

Very natural unclouded presentation current limiting fuses really work in protecting the amplifier. You can't kill the output transisitors. Good luck finding better at this price point. They also apparantly produce substantial current for a 100W amp, my Kappa's have claimed 2 amplifiers on my watch and 3 by the previous owner.

You can't say they cost $2k a piece LOL.

I bought my first 545II in 1995, it replaced a carver tfm 15cb. I later purchased a pair of Infinity Kappa 8.0's which much like their big brother the 9.0 can do a number on an amplifier. The above carver amp blew its output transistors in about 15min of powering the kappa's. The single 545II was still in over its head but could successfully power the kappa's to a reasonable level. I've have blown several of the "current limiting" fuses inside the amp, but the fuses have been totally successful in protecting the amp. Fast forward a couple years, I was visiting a friend out of state and noticed in his closet a 545II, asked him how much he wanted and I made off with it for $50. The addition of another 545II made a huge difference in the output, bass response, width of soundstage and clairty. I use them in a bi-amped config, they still lack the power to really extend the Kappa's in the low end, but the mids and highs rival any amp I've ever tried with these speakers. I was initially told to not even bother powering the kappa's with anything less than an amp rated a 200w, the 545II's hang in there, I push them hard, the channel powering the woofers gets extremely hot but I can't kill these things, just have to keep a supply of fuses on hand. A definate over achiever.

Similar Products Used:

Aragon 8008, sunfire sig., Nakamichi PA-7II, some lowly carver stuff.

Very transparent. Very smooth bass with out adding a sound character of its own. And very good on a wide veriety of speakers.

Might not stand up to the best the high end has to offer but it will hold its own with anything and will not cost you your house,car, and dog to own.

I have used this amp for several years now and all I have to say i wow. I have worked in the audio field for years and even though I am out of the business now I still follow the audiophile world pretty closely. When we had this amp in the shop that I managed I used to have reps or customers bringing audio equipment in all the time to compare. One thing I will tell you is that several times I had people bringing in 2 to 3 thousand dollar amps to audition a pair of speakers for there system and when their amps were hooked up they did not have the same sound quality of the 545II. I love this amp because at this price most common audiophiles can afford it and not have to take out a mortgage to finish their audio system. And this unit is well built, clean and very dynamic for a amp of this little cost. For anyone that downs this amp they are ussually comparing it to multi thousand dollar units(that they had to work overtime for a year to afford). Plus the fact that when they do notice differences they are ussually so small that you would have to concentrate for extended periods of time to hear the differences. My advice to anyone looking for a quality sound is to look for a good deal on this amp used from a good source and use the money you saved from not spending 2 or 3 thousand dollars on a power amp and buy a far better pair of speakers with that money because you will notice a difference in better speaker way more than you will between a 545II and any other amp that is overpriced. Remember most of your audio designers out there stick out of this world price tags on their equipment because they know that some people think they have to spend ungodly amounts of money on equipment to have quality sound and most of the time they are wrong. When Adcom designed this component they had real world people in their thoughts. Basically they were answering the needs of the common family mans need to have high end sound with out causing a difforce in his life due to spending his life savings on a darn audio system. Its quality folks not quantity, And Adcom delivers the goods.

Similar Products Used:

I have worked with several brands of audio gear. And have had customers bring in all brands of amps to test against the adcom and also to test speakers for purchase. People cannot believe the sound of Adcom for the money spent.