Very powerful

none at current price levels

Justin Busch below is mistaken when he said: "Contrary to what a reviewer below said, this amp is not "high class A biased". It runs hot, but that's due to the H/K receiver-quality heat sinking inside, not due to keeping the transistors on constantly." In order to confirm that, simply connect this amp to a UPS that has power utilization indicators. You'll see that even when the amp is idle, it draws a considerable amount of power.

Overall, a great amp. Priced at $600 is a steal.

Similar Products Used:

A lot

Clean transient sound, very dynamic for the price, cool looking

Cheap power cord (replacement makes big difference)

Few years back HK was the best component in my system and now it is the cheapest one. Let's start with the sound: excellent in its class (100X5. It beats hand down most receivers such as Marantz 7000, 8000, SR18 and HK510, 7000 in dynamic and clarity of music.
To bring most out one should consider cables matching. Power cord was replaced with AQ 12 gauge and what a difference noise level down, dynamic and bass are up. Of course you have to be familiar with screwdriver to remove over 30 screws for such replacement but definetely recommended.
Speaker cables can make big difference with this amp. AudioTruth Forest was slightly bright, while cheaper AudioQuest Midnight made a magic with very neutral sound.
Midnight is quit dark byitself so it muted HK harshness.
Use spades for connection and you will feel bass improvements over bananas immediately. For those who thinks that bass isn't enough try to go with better interconnects such as Transparent Music Link Plus and you will wonder why do you need a subwoofer. Keep it for DTS.
After all components were steps above HK I decided to upgrade it. Having Sunfire as preamp Sunfire Cinema Grand was reasonable choice. Obviously the difference in sound was considerable, but having omnipolar speakers extra soundstage was overwhelming. Somehow extra brightness was slightly annoying, and amount of bass was staggering for an apartment so Sunfire went back. Next step was B&K Reference 2220. The dynamic was better on B&K but very marginal. I would expect quite major difference from 2x225W amp. Soundstage, bass and clarity were slightly better but barely noticable to justify the purchase. Difference with Sunfire was quite major.
Overall with right cables HK can compete with bigger guys for much less.
The rest of the system
CD player: Anthem CD-1
Preamp: Sunfire Theater Grand
Speakers: Soliloquy 5.3 and Mirages OM10
Sub: Mirage BPS150
Cables: Transparent Music link Plus, AQ Midnight, AQ Digital Pro

Similar Products Used:

Many receivers,Adcom, B&K, Sunfire

I don't normally write to argue with critiques of my posts, but I feel obliged to respond to Joe C., who clearly doesn't understand what transistor bias actually means. When I said that the transistors aren't on all the time, I meant only that they're not drawing a high enough current to constantly be amplifying. This is not the same as saying that they don't dissipate any power. They do -- a lot. But unless the amp is drawing about 750 W continuously at idle, no way is it class A -- that would be about the minimum idling power given its per-channel rating, and assuming a typical "8-ohm" speaker load. Saying that it draws power at idle doesn't prove it's class A.

And dare I say -- so what if it isn't? It's an excellent, transparent amp, and can be enjoyed on its merits.

Clean-Powerful-Handsome-Great sound stage

None

A quick review would be to purchase this amp if you can find it! Probably the finest investment I have made...This amp has clarity in all stages [audio & theater]. The High current 100+/-amps is what makes this baby stand up to any demands from your speakers.No hum, just clean audio. Firm bass, good highs and nice mids give you a well balanced feel.I was thinking of selling it and getting a THX certified amp [Denon Poa-5200] to go with my Denon 5800 but I am reluctant to let this go, even MY Wife said "you're not going to sell this are you" That's a statement in itself right Guy's! I have had absolutley no problems or complaints with this amp, None!I use this specifically for my front speakers only [music]even-though it is a 5 channel amp [which I used when I first picked it up now I have 7.1].Everytime I play music I turn on my Denon 5800, switch to Pure Direct Mode, switch on the HK 2.1 and I could'nt think [or heard] of anything that could sound better,I am sure there are but, I really don't want to take a chance and part with this Amp..Maybe when The Denon Poa-5200 or B&K gets a bit cheaper I'll pick one up as a backup...Maybe
It's too bad HK is not making any more of these. A couple of their recievers I tried.. well.......HK needs to re-think..and get back to where they used to be..[High Standards]...Pick up this amp really!! it's a good investment.................

Similar Products Used:

Denon HK

Lots of Clean Power

none so far

I used a Yamaha RX-V995 Receiver to power my system. While I love the unit it seemed to just be missing something at high listening levels. So I decided to put a power amp behind it to help out. This is the fist time I have ever used seperates - boy was I missing something.

I looked at several units - Rotel, Marantz etc . Then I found this unit at $500 reconditioned, the sound was as good or better then the other units and given it still has a 2 year HK warranty and such a low price tag - how could I beat it. The sound is crisp, clean, potent and works great with my 995 - now used as a pre amp.

Yamaha RX-V995 Receiver/Pre Amp
Harmam Kardon DVD5
4 - NHT 1.5's
NHT VS-2A Center
Velodyne Subwoofer
Technics SL1800-MK2 Turntable (still running great 18 years later)
Monster Interconnects all around
12 Gauge Recton Speaker Wire
Room Size 20x20

I highly recomend this unit to anyone who needs a 100 Watt amp.

This is an amp for the serious listener! As well as a great bargain. It has a smooth powerful sound. It is apparent that the high current, + or - 100 amps, can drive a couple pairs of great speakers with clarity and accuracy. Perfect for a home theater application this "heffer" wieghs in at about 30-40 lbs. I have it powering an older pair of infinity ref. 5 (back when they were great) and it continues to amaze me each time I listen to it! It is simply one of the best.

The Signature 2.1 is the best amp under $ 1000.00 ; I got it for $ 979 delivered from www.onecall.com. About 50 lbs ; massive heatsinks ; 2 massive capacitors per channel for a total of 10. Huge toroidal power supply with individual secondary windings for each channel. Very good build quality ( Made in US ) and excellent sound. High Current design ; 100Wx5 at 8 ohms ; 150Wx5 at 4 ohms ; power consumption 950 watts max.

GREAT AMP,GREAT VOLUME LEVELS,GREAT DYNAMICS. I HAVE A FULL SET OF MAGGIES FOR MY THEATER/LISTENING ROOM THE H/K SOUNDED VERY DETAILED AND FULL,BUT LACKED THE NECESSARY POWER OUT PUT TO RUN THE MAGGIES TO THEIR FULL LEVEL. NOT TO SAY THE H/K IS WEAK IN ANY DEPARTMENT BUT MAGGIES RUN BETTER AT 250+ WATTS. I WOULD RECOMEND THE H/K 2.1 TO ANYONE WHO DOESN'T NEED SUCH WATTAGE AS I DO.AGAIN GREAT AMP,GREAT VOLUME AND DYNAMICS.

Sound quality

Power supply inadequate, heat sinking inadequate

This is a quest to do something better than mid-fi typical of home theater amps. Electronically designed great, low distortion without abusing negative feedback, and it shows when you listen. 2x75 voltage, good; a battery of capacitors in power supply, good; toroid power transformer, good. Heat sink assembled, not cast, bad; obstructed air flow through heat sink, terrible; weak power supply, bad. I bought mine for $730 open box at Circuit City; for this money a perfect home theater amp. May be a find for DIY enthusiasts - with adequate heat sinking, better power supply and more bias towards class A may be made hi-fi for 2 channel stereo. There is ample underhood space for these upgrades.

Similar Products Used:

Denon AVR2500

Very good power amp,clean sound ,good buy for home theater.look gook

very good