Very intelligently thought out. Built like a tank. Very powerful, very high current. Sounds like a dream!

None.

This is one amazing amp! I used to own a Sunfire 300, until I auditioned the floor model HPA3 for a weekend. In the first 5 seconds of listening, I notice the control this amp had over my speakers. Layers and layers of detail, airiness, liquidity, palpability just leapt out at me. Everything had a very keen, natural sounding harmonic structure. Separation of instruments, soundstaging, you name it. Every instrument existed in its own space. And if you think that sounds good, upgrade the supplied power cord! This amp is all about detail and it will reproduce what it receives very well. Upgrading interconnects from my CD player was very revealing (AQ Pythons), as well as my pre-amp upgrade from a McIntosh MX-130 to a Lexicon MC-12 v2.00. As for other features, both balanced and unbalanced connections are level matched, and there are switches on the rear panel to select the connection of choice. This amp does have a standby mode, in which it keeps charged and warm for consistency. Now for the petty stuff... At a MSRP of $4500.00, I think the speaker terminals could have resembled those of the Mark Levinson line. This amp also does not accept bananna connections, which I don't use anyway... Needless to say, I'm really enjoying this one! (I can't wait to get my Levinson!)

Similar Products Used:

Sunfire 300

Bass control, power

bright

Yet another unscientific review. I had this for only 3 days for an audition and waited until I got a Classe to review for comparisons' sake. Some history: I told a dealer I was thinking about blowing 3 grand or so on used amplifier and wanted to audition the Sunfire Signature amp with supposedly outrageous 600W/8 ohms/1200/4ohms. He suggested an HPA-2/3 instead knowing I had decent speakers (Duntech "Black Knights" and pre-amp (Proceed AVP) and was willing to loan me the HPA in the hopes I would opt for this product as well.

I took the HPA-3 home over the weekend for a tryout (they did not have an HPA-2 in stock). My reference was the Adcom-5800 amp with same rated power into 8 ohms (250W/8) but "sagged" under load into 4 ohms and lower. In contrast, the HPA-3 "doubles-down" into 4 ohm loads. Since my speakers (Duntech "Black Knight"/Regent D400 "clones") have impedance dips as low as 2.8 ohms, amp current capability was important consideration despite decent sensetivity (89 dB or so).

The HPA-3 certainly outshone the ADCOM-5800 but it certainly should for more than twice the price ! The differences were pretty subtle IMHO but I guess what do you expect at this price range? Much tighter bass control and the treble was so much more apparent and crystal clear. Unfortunately, the sound was very bright IMHO which was probably aggravated by the rooms's reflective surfaces (ceramic tile, brick walls, and lots of windows). Drapes are coming soon and "throw rugs" have already been tossed down !. Also, the sound seemed very "analytical/mechanical" and did not appeal to me. The bass was tight but I got too much an impression of "non-engaging thud".

In contrast, I managed to get a local audition of a used Classe-300 amplifier with a tad more rated power, "doubles-down" into 4 ohm loads (600/4) at less than 2/3s the price. The Classe is often compared with the Levinson/Krell offerings at half the price allegedly due to Canadian/US currency rates. The Classe not only was cheaper (unfair- used vs. new but I do have budget constraints) but was able to deliver more rated power and seemed to sound more "musical" and "exciting" when compared to the Proceed HPA. Maybe there is something to Classe's decision to use more and smaller capacitors to provide better flexibility/microdynamics than Madrigal's use of larger capacitors. I suspect the Levinson/Krell offerings may try to provide better sound reproduction (aka tighter bass control) but the Classe offerings seemed to provide decent bass control combined with a more engaging midrange and treble. I liked the tube sound of the Mcintosh top-of-line $15,000 amp but I cannot afford this unit nor do I want to mess with tubes so Classe might be the closest match to tube sound that I can find with solid state amps. I've yet to drive the speakers/Classe Amp into distortion IMHO for my listening tastes. I.e. the Classes seemed a better fit for my tastes then Madrigal's Proceed HPA offerings...

In a side note for HT buffs, I have a much better understanding of the need for adequate amplification in the rears and Center. When I used 1 of 3 HPA-3 channels for the center and the ADCOM-5800 (in lieu of ADCOM-2535 60W/rear channel) for the rears, I detected a world of difference in HT mode. For this reason, I elected to buy into the Classe-300 in the near term instead of holding out for the CA-400/401 as I wanted "immediate gratification" for the surround amps and this allowed me to immediate relegate the ADCOM-5800 to the rears. I eventually will want to put the CA-300 in the rear to support full-range rear speakers. Still deciding on Center speaker amp..... Then what to do about side speakers for "7.1" surround mode as I have a large HT room to deal with?...sigh. Nevermind the subwoofer (or lack thereof..) problem ....

Current system:

Duntech "Black Knight" speakers
Def. Tech BP-2 surround speakers
"home built" Center speaker using Dynaudion tweeter/mids same as "Black Knights"
Classe CA-300 amp (mains)
Adcom 5800 amp (rears)
Adcom 2535 amp (center using bridged mode)
Pioneer Elite DV-05 DVD player
Pioneer Elite CLD-53 Laser disc player
Yamaha CX-1 pre-amp (standby mode)
Proceed AVP Preamp/processor

Similar Products Used:

ADCOM-5800, Classe CA-300

A beast for HT. Power to the hilt. Built for a lifetime of service. Merk Levinson Output Stage. Stone Quiet.

Heavy (120 lbs.)

I use one of these for LCR speakers in a 7.1 configuration of Bohlender Graebner ribbon speakers which are a resistive 4 ohm load. The BPA's are a perfect match as they provide a huge power reserve (500 watts per channel).

They use the same output stage as some of the Mark Levinson amps, 'nuff said. The units are extermely accurate and neutral. The balanced inputs are just that. I run 7 meter balanced cables from bettercables.com. There is no hum whatsoever. Bottom line, my quest for ideal amps is over.

Similar Products Used:

Cinepro 3K6, Sunfire, Coda

Bass Control, Tri Mono amp design, Imaging, Clarity, Power

Price, heavy peice of equipment

I got this amplifier to maximize my speaker’s potential. Previous to the HPA3 purchase, I used 3 Marantz monoblocks (MA-500) to power my LRC speakers. After upgrading my speakers to B&W N805's and my surround processor to the Proceed AVP and my audio cables to Transparent Musiclink Super interconnects, I realized the limitations of my amplifiers. To improve my bass control, I began my quest for a replacement amplifier. I narrowed my search to the Proceed Amp 5. Upon auditioning the Amp5 at my dealer, I rejected it. It had very good highs and mid range however, the bass was lacking in my opinion. I decided to do an in home audition of the HPA3. I all I can say is "WOW". This beast has all I was looking for. Superb bass control. It delivers fabulous clarity in the highs and midrange. My soundstage opened up. My L & R speakers are bookshelf and by design, they are light on bass. With the addition of the Proceed, the bass from my speakers was resurrected. With my sub-woofer for HT use, I am very satisfied. I had a visitor who had heard my pre-proceed HPA system. He said smiled and commented he could hear the difference as well as feel it. During movies, the definition is astounding and the dialogue is more natural sounding. The discrete sound effects are much more realistically implemented now. I feel I now have the ultimate amplifier for my system. I occasionally visit high end dealers and, come home still very satisfied with my system (a first for me).

My system:

B&W N805 L,R Speakers
B&W HTM1 center speaker
M&K SS150THX L,R Surround speakers

Proceed AVP Processor
Proceed HPA3 Amplifier L,R,C
Marantz MA 500 amplifiers L,R, surround

Pioneer DV-09 DVD player
Sony KV-36XBR400 Television

Transparent Cables Musiclink Super Interconnects
Bettercables Premium speaker cables

Similar Products Used:

Marantz, Rotel