[albee]

Imagine a paperback book about 275 pages thick that weighs just less than two pounds.  Now, add five small knobs and an equal number of pushbutton switches and you have the incredible bulk-LESS 903.  It’s a small, compact piece of metal that can shiver your sonic timbers at a price that will make the any audio skinflint smile.  This compact package delivers a lot of features for the money and is classified as an integrated amplifier that features three standard RCA source inputs and one standard 3.5 mm input for the “pod” of your choice.   It has Balance, Volume, Bass, Mid, and Treble controls via some of the best fluid-feeling knobs you’ve ever twisted.  It also features a Loudness control that most will never have any reason to use.  The amp section is rated at 10 watts RMS into 4 ohms, so let’s pretend it’s 5 watts into 8 ohms or about one watt less than the standard SI 5066.  


The first thing that grabbed me about the 903 is the way it put the “iron fist” on my Klipsch Reference speakers.  I’ve never heard more dynamic or detailed bass from any of the amps I’ve ever owned.  The midrange is alive with detail and dynamics and the treble is carried off better than any digital amp I’ve tried—not that I’ve tried any really expensive amps.  Channel separation and imaging is very, very good with vocals well centered and just an inch or two ahead of the soundstage.  The top end is smooth, detailed, and comes close to having the sparkle much more expensive amps or analogue sources might have.  Being a treble freak I find it very satisfying in its presentation.   One other observation is that the 903 doesn’t have the same amount of midrange warmth most Tripath devices have.  This I like and, to my taste, does not detract from the overall sound at all.

I primarily listen to electronic, techno, new age, and classical.  (Kraftwerk to Wagner and everything in between—so to speak.)  This kind of “music” soars on the 903 due to its “iron grip” and detailed delivery.  This amp definitely has PRAT (pace, rhythm, and timing) and I find myself head-bobbing and toe-tapping right along with the music.  Just remember the 903 doesn’t have quite to power to propel you off the sofa to fire up the disco ball.  Relax and listen actively.

The 903 will definitely perform if your speakers are at least 92db or higher.  My speakers are advertised at 96db but in reality are 92db on stands.  This amp has more than enough juice to be as loud as I would need sitting 9.5 feet from the speakers.  I usually listen, at the sweet spot, between 80 to 85 db  which is getting loud!

Caveats:  There are some imperfections to deal with.  The 903 comes with a 2.1 amp wall wart.  The amp is designed to stay powered up at all times as every time you power up or down you will get a resounding thump through your speakers.  I tried both a 12v/2amp and a 9-15v/22amp power supplies before settling on a 13.8v/3amp box.  The 903 sounds best with the 13.8v drive and even though the case is imprinted with 12v the unit is designed to handle it.  I also use a SLA battery powered jump-starter which smoothes out the sound and further deepens the soundstage.  (Note: I’ve found with various Class D cheapskate devices that the size of the current “pipe” has noticeable effects on the sound much the same as rolling rectifier tubes.  The smaller wires that come with wall warts tend to flatten the soundstage and emphasize the top end whereas a larger wire will increase dynamics, grip, and deepen the soundstage.)

Another imperfection would be the 903 speaker-terminal block connector.  Such a small package has to compromise somewhere and this is where it happens.  The block is very small and accepts only well-twisted and tinned 16 gauge bare wire at the maximum.  My Mapleshade wire fits nicely and is about 18 gauge.  The block requires a jeweler’s screwdriver and a delicate touch to tighten down the wire.  Once in place don’t be moving the amp around unnecessarily and check the connections often to make sure they are secure.

I originally got the Kramer as a headphone amp but just had to hear it through the speakers and, WHAM, I was hooked on its sound.  For the price, this is the best sounding thing for the money you can get in Class D.  If you’ve had a Teac or SI (like I have, among other units) try this before plunking down for the Super SI or a modded Tripath unit.  The 903 cost a little more than a retail Super SI and much less than a modded unit of any kind plus having the flexibility of source selection and the ability to tailor its sound through the tone controls make it a really satisfying music lover’s machine.

When I first got the unit I had a few questions and got really great responses from Kramer’s tech support unit in NJ.  They are ready to help you out and seem to be seasoned pros.  You can find some info on the 903 here:

 http://www.kramerelectronics.com/indexes/item.asp?desc=52

The best price I found (at the time) was at Garrett’s plus the service was fast:

http://garrett-smarthome.com/products.php?cat=352&pg=8

Finally, I would recommend the 903 because it doesn’t break the bank, it sounds damned good, it seems to be a top quality product, and can be used in a first or second system.  Despite my unbridled enthusiasm I am in no way connected to either Kramer or Garrett’s.

[dwc]

Thanks Albee,
They've already got you linked as "the review" for the product.  Are you sponsored?  (I'm suprised they found your review and lnked to it so quickly)

IN any case thanks for the heads-up and this look interesting, esp since my JVC 201 just smoked!  

-Dan

[jackman]

Have you compared this amp to any of the others, like the ClariT or the SI Deluxe?

[albee]

dwc:  Me surprised, too.  I'm also on the HK dealer website for my comments on my DAC-AH.  Maybe I should buy stock, huh?  

jackman:  I got in on the Powerwave thing when it was the only game in town.  Moved to a 2020 eval board for a while which sounded a lot diffent than the Powerwave (2024 chip).  Got a big Blaupunkt Tripath car amp that pushed out 70 to a 100 watts per and it was rather murky sounding.  Blau discontinued it because, IMO, they blew it in the power supply as the thing ran as hot as a firecracker even though they advertised cool as a cucumber performance.  As yet they have not returned to Tripath.  From Blau to Sonic Impact.  This amp proved the 2024 has more magic than the other Tripath chips.  I have had a total of four but two went dead--QA for 20 to 30 bucks just doesn't exist.  Next came my Teac at 30 watts per.  Not sure which Tripath chip but most here would know that it doesn't sound much like the 2024.  To me, it was a drier sound devoid of the mid range syrup I've always heard out of a 2024.  In fact, I alternated between the Teac and two SI (bi-amping).  It was sort of a toss up to my ears.  The Teac sounded better balanced by being leaner while the 2024's sounded more musical/tubey by being a tad thicker in the lower mid range.  I was using a cheap but reasonably transparent preamp (Cambridge Audio) that required me to acutally tone down the bass to clear up the lower mids of both amps!  The SI's required the most adjustment although the Teac would actually go lower.  

I don't even know how I found out about the Kramer line.  I was looking through a discounter's site and came across Kramer on a price list with a stock shot.  The 903 is the Class D box of their personal amp line and relatively small compared to everything but a SI.  The price is a little over the Super SI (which was not available at the time) so I decided to give it a whirl.  The speed and dynamics are, to my ears, better than any of the other above listed pieces.  Keep in mind you will only get 10 watts @ 4 ohms and I have 8 ohm speaks, myself.  I don't have a clue as to what the topology of the amp unit itself is but when you see the small case you immediately know what you see is what you cannot mod.  I suspect the bass output has been tweeked just as the Powerwave and SI sound--but this is not a bad thing.  Remember you have tone controls with which to tweek.  Based on what a Super SI costs, I decided to go ahead and try this unit with its flexibilty of controls and sources.  This would work great in a second system or bedroom if you can live without a remote.  I realize to a lot of guys the 903's price is starting to approach a Class D receiver.  I just depends on what you want, I guess.  I have no time for FM and use mine for music and movies.  Oh yes, I think Kramer just upped it's warranty from 3 to 6 or 7 years.

Over the past five years, pre-Class D hysteria, I was using an Acurus DIA 100 and Zen Select.  Class D really puts <$1,000 tube amps to bed due to lack of required maintenance if nothing else!