NEUTRAL,STABLE,RELIABLE,COMPACT,RUNS COOL,EXELLENT BASS CONTROL,POWERFUL.

NONE WHEN PRICE TAKEN INTO CONSIDDERATION. IN ABSOLUTE TERMS, SOUNDSTAGE BETTERED BY FAR MORE EXPENSIVE SOLID STATE AND TUBE AMPS.

WONDER LITTLE AMP. PROBABLY ADCOM'S BEST. KEN KESSLER WROTE IN HIFI NEWS RECORD REVIEW, "AND AMP FOR KRELL AND LEVINSON WANNABEE'S". I CONCUR. ( I'M SURE HE'LL BE RELIEVED TO HEAR THAT.) VERY QUIET, MUSIC SEEMS TO COME FROM A BLACKHOLE AS IT WERE. GOOD EXTENSION AT BOTH EXTREMES. TOP CAN BECOME HARD, ETCHED IF PUSHED TO HARD. BUT WHAT SOLID STATE AMP DOESN'T? THE BOTTOM END SEEMS A LITTLE DRIER THAN THE REST OF THE FREQUENCY RANGE BUT NOT OVERLY SO.THE MIDRANGE IS JUST THERRE. THE AMP REALLY HAS NO SOUND OF IT'S OWN WHICH I THINK IS THE HIGHEST COMPLEMENT ONE CAN PAY A PIECE OF HIFI GEAR. SOUNSTAGE IS BETTER THAN ONE HAS A RIGHT TO EXPECT AND CAN SURPRISE WITH THE RIGHT PROGRAM MATERIAL AND ASSOCIATED GEAR. 2+ db HEADROOM MAKES THIS AMP SEEM MUCH MORE POWERFULL THAN IT'S PUBLISHED RATING.I KEEP MY GEAR A LONG TIME WHEN I LIKE IT AND I'VE BEEN USING THIS AMP FOR 12 YEARS!I'M LOOKING FOR ANOTHER TO BI-AMP MY VANDERSTEENS. THAT SHOULD TELL YOU ALL YOU NEED TO KNOW!

Similar Products Used:

SAE MK 25,FISHER 500C,NAD,KENWOOD

Soudstaging is average but everything else it does extremely well with proper matched components and quality interconnects.

Considering the performance of this amp and it's price point, it hardly deserves a negative comment.

There are many Adcom products I like and the GFA-545II is one of them! They give you alot of bang for the buck and usually you have to spend quite a bit more to out-do them. Many people think the Adcom power amps have to be mated with an Adcom preamp which is the furthest thing from the truth. I enjoy trying different preamps with this product (including Adcom), to try and get the best sound quality. I have found the B&K PT3 series II to be an excellent match, bringing this amp to a whole new level of sound performance. I suspect many amps garner poor reviews because they are poorly matched with preamps and the source components aren't up to par. I prefer the 500 series to the 5000 series. One reason is the 500 series uses bi-polar transisters as opposed to mosfets which are used in the 5000 series. Well it is true that mosfets are thermally more stable and sound good in a well engineered amp, but they also clip alot sooner than bi-polars. Anyway this is a fine power amp for the money and be sure to buy quality inter-connects to fully realize the potential of this amp.

Similar Products Used:

Musisc Fidelity, McCormack, Bryston, McIntosh etc

Good value, easily upgraded

slightly thin sounding

I bought this Amp new cheap as I knew the dealer well, I was always happy with it but it did sound a little 2d and harsh. Took it to Avondale Audio in Chesterfield UK who replaced the power supply with an external unit, worked the chasis for better isolation replaced the internal wiring with better stuff and voila awesome! Driving my Monitor Audio Studio 12 speakers is a breaze for this thing. I have looked at replacing it recently and auditioned the Naim Audio NAC/NAP combo, the TAG Mclaren and many others and non get near this thing. I guess i will have to spend £2000 to better this and i am not going to!

Similar Products Used:

Naim, Arcam, NAD, Linn etc etc

Silky mids and pleasing highs.

The bass is a bit loose but who cares I am bi-amping anyway with one of the best bass driving amps under $1000, the Kenwood basic M2's Those babies still have killer bass, tight and sweet.

I have extensively used the 555II in various configurations. I got the Mk.II when it came out, it had Toshiba parts, it sounded ever so good. The bass was a bit clunky but the mids and highs were nice. Fast forward 10 yrs. I get this 545II that I see on ebay for $170, I chase it and end up paying 241, which is not too bad. As soon as I powered it up, it was heaven revisted in the mids. I then thought I'd get a 555II again as the 545II did not have enough oomph, I got one, powered it up ..... It was terrible! Compared to the 545II, the 555II was harsh and had no details. I open it up and find it has 3 brand of power transistors, Adcom ADC's, one Toshiba and a pair of the dated and horrible sounding MJ15024/25. Sure dude pair up a MJ15025 with a Adcom part, it will sound bad. I then scoured the Internet for original Toshiba parts. (They don't make them anymore), found a place, ordered them and put them in. Ahhhh they sound mucho better, however not as good as the 545II's. So I am bidding on another 545II to use two 545II in bridged mode and selling the 555II to get the funds to do so. This is good! Oh by the way don't get the original 545, I have heard they sound bad compared to the 545II's.

Similar Products Used:

Adcom 555II, Krell KAV-250a, Carver Sunfire Signature (Worst sounding amplifier above $50 period.)

Powerfull!!!

I got my amp from a friend about a year ago. He got newer adcom stuff so sold me his old Adcom 545 Amp for $250. This amp is more powerful than my last Kenwood amp. It gots lots of juice. I have Bose AM-5 speekers and good (gold) wires that I plug it in with. My friend said I should buy better wires now that I got such a nice amp. He told me that ADcom is the best amp on the market. He was not kidding. Now I can Jam my music sooo loud!!! I jam it all day long. The only problem is that I can't even turn up the volume half way before my speekers start making a funny popping sound. I guess I will have to save some money to buy a cerwin vegas, bigger bose, or polk audios that can handle all that power. Wow can you imagine the sound I will get. I am not sure why you guys say the amp is transperent. My amp is LOUD!! not transperent. The only problem is that no one has heard of adcom. I went into best buy to listen to bigger speekers but they didn't even know what adcom is. Imagine that!!! I never heard of the speekers you guys are talking about but I'm sure that you will like your amp more with Vegas or tower speekers. They rock!

Similar Products Used:

Kenwood Reciever, Yamaha Reciever

Overall decent sound for the money

Thin but tight bass, tizzy high end (at the very high end) thin

My review will be a lot like Pete Wellhofer's. I like the Adcom, but after doing A/B tests between it and the McCormack, the Adcom seems more like Mid-Fi than Hi-Fi. Then again, this was the same thing I noticed going from my old Carver to the Adcom. As noted, the Adcom has a thin but tight bass, a tizzy high end and overall is just not as musical as the McCormack. Even so it is still a decent product and I will keep mine as a spare.

Current system:
Amp: McCormack DNA-0.5 Deluxe
Pre: PS Audio 4.6 (Always in straightline mode)
CD: Dennon DCD-1520
D/A: Audio Alchemy DDE-1.0 w/PS1
Speakers: NHT 2.5i
Cables: Interconnects-AQ Lapis(old);Speaker-AQ Indigo (shotgunned)
Power Conditioner: AudioPrism Power Foundation III

Similar Products Used:

(Currently)McCormack DNA-0.5 Deluxe, Carver M500t

Good power for what I paid. Good detail. Well Built. Runs Cool. Dime a Dosen USED!!!

Lacks the soft airy sound of really expensive amps. Dosn't sound warm.

The amp is a good solid piece. Mine is quite old and still performs extremely well. I have heard that ADCOM is good about service but I am not anticipating any. I have heard many amps that sound much better on imaging and depth, but most of them you can't pick up for less than $400 used. These are great for the budget tight consumer. I only use mine for a small 2 channel music system in my bedroom so for me it's great. It needs a little more power if you want to drive big speakers but it does deliver the rated amount of 100 watts.

Similar Products Used:

Denon, Sony "Don't Laugh", Rotel, Classe, Aragon, Acurus.

Good power, and smooth bass reproduction.

Highs are a little harsh at times and the midrange is a little washed out. Not real bad though.

I purchased this amp around 1995 and have been very pleased with it so far. I am always looking and listening to other amps (other equipment as well) with hopes of upgrading the sound quality of my system. But, to date I have not found another amp (in the under $1000-$1500) that will match the my system like the Adcom 545 II. Some of the other amps may have better midrange but their strong points don't out way the Adcoms bad points. As I mentioned earlier the biggest fuss I have with this amp is that the vocals can seem a little distant at times. But at $500 I don't think you can go wrong. For sound quality I would give it a rating around 3-3.5 But, for what you get for the money it has to be a 5. So I'll average it to a 4.00

Similar Products Used:

Rotel, McCormack, Hafler

I have owned an Adcom 545 for about 10 years now. Wonderful amp. I drive a pair of Magnepans with it, and have an Adcom Tuner/Pre GTP-400 with it. I haven't had any problems with either one and they sound great. If you can find a good used one, I highly recommend buying it.

extremely clean, tight and well defined sound for the $$$, solid construction

very revealing of lesser componenets

I've read the reviews posted on this sight and all I've got to say is "WHAT DO YOU WANT!!!!!!!" This amp retailed for $650 IN 1991!!!! The ps audio counterpart of that era was $2000, the carver $499 (the carver is the worst sounding amp ever made), NAD (Normally Always Defective)$800 and B&K $1500. It has a warmer sound, tighter bass, and more low end heft than all of the previously mentioned. The B&K is the only one that might have equaled it in low end, but nothing else. I know, I listened to them all in 1991 and was absolutely astounded at the bang for the buck of the 545II and bought it a week later. They ran my old pair of Infinity Kappa 5's, god I miss those speakers, in my dorm room. The adcom over powered them. The woofers blew about three years later in a home theater accident having to do with my, than 1 year old, daughter. These speakers were 100 watts into 4 ohms, with the emit K tweeter, even infinity said it was more like 2 or 1 ohm. The tweeters were fine by the way after the incident with my 1 year old. I've had this amp for 10 years and have never had a problem with it. It sounds just as good as it did back in 1991 and is driving a pair of 150 watt Dahlquist speakers famously, with more than enough low end!!!! Unless you wnat to drive a pair of Kappa 8's, 9's, Martin Logans or B&W Nautilus your not going to need to by-amp this puppy. Shame on any one that knocks a $650 amp that sounds like a $1500-$2000 of that era. You can now pick it up on e-bay for $400 or less. This amp is a bargain you snobs!!!!!!

Similar Products Used:

nad, ps audio, parasound, carver, B&K and 2 or three others that I can't remember off the top of my head