I purchased the Krell KSA 150 from High Performance Stereo in Florida. They replaced all the caps in the amp. It sounds amazing through my Acoustat 1+1s speakers and subwoofer system. It does run rather hot as any Class A amp design from this amp's original period in history. I measured the heat sink fins at 60°C

Pre-Amp: Classe SSP-600

~ Very good macro-dynamics. ~ Bass has excellent attack, crispness, and depth. Not quite as full or warm there as its peers, but great bass response nonetheless. ~ An arc-welder - can dump lots of current into extremely low impedances and tough phase angles. ~ 2 pairs of speaker posts, a plus for bi-wiring. ~ Krell build quality, natch.

~ Mids and highs lack the refinement of some other amps in it's power/price range. Can be somewhat fatiquing after extended listening sessions. ~ Could be better at micro-dynamic shading and texture. ~ Edges of faceplate and heatsink fins can injure if careless while moving this heavyweight.

Owned a KSA-150 back in 1994, but I do remember the sound of it well. In fact, I always write down my impressions of a piece of gear throughout the period that I own it in case other components change in or out, I have a better idea of which units do well together and which don't - and why. But I have wanted to post my observations here, since I don't think many of the reviews I'm seeing on the KSA-150 & '250 are all that accurate. I've owned a lot of amps before and since the '150, and some definitely had better mids and highs, and comparable bass response, while others of course would fall flat in the presence of the Krell. The ease by which this amp can handle any speaker made is useful for those who need to drive difficult loads like certain Martin-Logan's, Apogee's, Maggie's, B&W's , Thiel's, etc. However, even with its big current capability, it can be pushed into hardness with "only" 150 wpc/8 ohms. But for all of its positive attributes, I never could really feel completely satisfied with the '150. That's because from the midrange and up, it just seemed too aggressive and unsubtle. Not only because I've been a tube amp fan, but because I know other SS amps can display dynamics, control, bass response, and soundstage specificity like the Krell, but they can do so with greater finesse and attention to micro-dynamics and harmonics. The KSA-150 is a good value on the used market for around the $2K point, as an anchor for the low end in a bi-amped system, or if you have very low impedance/low efficiency speakers. As a full-range, main amp - there are better choices sonically. I give it 4.9 for bass response, 5.0 for low impedance handling, and 4.95 for build quality, 4.8 for macro-dynamics/power handling. 3.0 to 4.5 for everything else.

Similar Products Used:

Partial list: original Adcom GFA-555 & '545, ARC Classic 120 monos, Audionics CC-2? (60wpc model), BAT VK-300X, B&K Sonata EX442 monos & ST140, Classe' DR-8, Golden Tube SE-40, Lazarus 200/200, Levinson No. 383, Marantz 2250B (receiver), Mesa Baron, Pass Labs X150, Sony TA-N55ES, Yamaha MX-1000U, others.

BUILT LIKE A BRICK S--T HOUSE. SEEMINGLY UNLIMITED ABILITY TO OVERCOME ANY LOAD.

POWER CORD''S CHEAP BUT IT MAY NOT BE FACTORY. EAT YOUR WHEATIES BEFORE YOU HOIST THIS BEAST.

THIS AMP IS GOING TO KNOCK YOUR SOCKS OFF, THE LOWS HAVE NEVER BEEN THIS LOW. YOU CAN FEEL THE POWER AT ANY LEVEL AND IT SEEMS TO BE RELENTLESS. IF YOU CAN FIND ONE OF THESE AMPS ANYWHERE FOR GODS SAKES MAN GRAB IT!! I''VE BEEN ENJOYING MY ROTEL FOR THE PAST FEW YEARS AND FELT THAT I DIDN''T NEED ANYTHING BEYOND THIS UNTIL NOW. AS GOOD AS ROTEL IS,I''M SORRY TO SAY, THE KRELL BLOWS IT AWAY. IF I COULD RATE HIGHER THAN A 5 I WOULD.

very tube like sound killer bass
good match to the ksl preamp
drives my acoustat model 3`s nice

none that i can think of
hey its a krell

if u can find one of these amps buy it
my current system is as follows:
ksl preamp
ksa 150 power amp
mcintosh mcd7009 cd player
acoustat model 3 speakers infinity modulus 15 sub
audioquest midnite2 spkr cables
mit bal and single ended cables
this setup is very smooth with or without sub

Similar Products Used:

audio reserch
d110b

The deep low end.....Very dependable.....All the class "A" power anyone would need.....This baby delivers ...!

None....

I have couple the KSA-150 to a pair of Apogees slant 8's electrostatic speakers and there is no problem what so ever.....Above that i'm using the Mello's refrence(up- graded with balence inputs and outputs) pre-amp with vampire interconects.....Then on top of that i have the Monarchy 22b D/A converter with four Burr Browns inside piggy back....On top of that there is the Genesis Lens jitter box with the Sonic Frontier SFT-1 transport and last be not least is my baby the big bad Day Sequerra Refrence tuner with the "classic upgrade" ......From the Sonic Frontier to the Monarchy 22b i'm using the kimber D/60 bnc and sometimes i put in their orchid cable balance........ From the D/A converter down everything is balance in and out ....BLESS JESUS ...!!! FROM D/A CONVERTER TO THE APOGEE'S CLASS "A" IS THE ONLY WAY TO GO ..! If you run across a KSA-150 grab it and run buddy ...!

Ha, ha, ha, ha, haaaaaaaaaaaaaaaaaaaaaa............ i'm laughing my way to heaven! Just bought this collectible amp with huge fins from a second hand shop after 2 years waiting. Worth every Yennnnnnnnnnn.
CD - Teac VRDS 25X
D/A - Wadia 22
Pre - Krell KSP 7B
Pwr - Krell KSA 150
Spk - Apogee Diva
Cables - Siltech

Very happy and sayonara

Great, solid bottom end. Awesome dynamic capability. ....it's a Krell.

Darker side of neutral presentation. Extremely antiseptic reproduction. Unforgiving to poor quality audio companions.

I owned this amp with a pair of Martin-Logan electrostats. The panels loved the endless power and if you are a transparency freik, this was the perfect combination. Lacked some of the warmer, lush attributes of good tube amps. Every technophiles dream. An amp to be proud of. I owned one of the rare, black faced models with the single blue indicator lights.......it was the best looking amp I have ever seen. I would buy another in a minute!

I owned several Krell amps in the past, KSA150 is the first Krell amp I own. It offers traditional Krell characteristic--good bass slam. However, overall music presentation tends to sound little cold, compared to the KSA200S which I also owned it before. The midrange is little smoother than the early KSA80B, but I prefer the KSA80B overall presentation. FPB200 surpasses the KSA150 in every aspect. Visually, the KSA150 does looks very pretty, as a matter of fact, the KSA150/250 series are the most beautiful Krell series in my opinion. If you need a muscle amp, the KSA150 should be the first few choices around two grands budget. From price/performance ratio aspect, I give it 5 stars.

Recently auditioned this amp in-store. Excellent solid state amp. Great if you don't like the sound of tubes, and I don't! If you don't mind spending $2k on an amp, check this one out. 5 stars on sound, but only 4 given its price.

Unlimited Power / Extreme bass control / Huge heat sinks /
well balanced.

Generates a Lot of Heat, Very heavy to move, Sonicaly not much to complain about.

Short and to the point !!!!

If matched with the right pre-amp and Mit or Transparent balanced cables are used it does not get much than this!!
*My final match for balance was the Krell KSP-7B pre-amp and the Krell KSA-150 amp w/MIT Proline balanced cables.
Both units were from the early 90's and are around on the used market fairly cheap. (KSA-150 used=$2100.00 & KSP-7B used=$1100.00)
If you have a difficult pair of speakers like mine(Thiel CS 3.6's)this amp has all the balls you'll ever need, with plenty to spare. The sound still blows me and all of my friends and family away to this day.

POWER / POWER / POWER = KRELL

Similar Products Used:

Levinson#23 , Adcom 585(oops? don't know what I was thinking) , C-J 2300a