Vintage Krell

I just picked up a Krell KSA-200S to run my Magnepan 1.7i’s and am simply blown away by this combination. I have been listening to High Efficiency Speakers with Dual McIntosh MC240’s running in Mono, which have been terrific and very musical, but this combination for a Solid State is a keeper!! The AMP is a BEAST!

I had KMA 100's, same vintage and design as the KSA 200's. They were fabulous sounding amps. After twenty carefree years one of the output stages let go. It is what happens to full bore Class A amps. Semiconductors may be more tolerant of heat now but they were not back then. Just like an incandescent bulb you can only turn them on and off so many times. So my advise is stay away. Even having it rebuilt will not guarantee either longevity or sound quality. 

I had KRELL KSA 50MK2 great sounding amp even by todays standards.

I really liked the KMA 160’s & 400’s!

I owned a pair of MDA-300 monoblocks in the late 80's, early 90's. They generated a lot of heat, but I loved the sound. My wife convinced me to sell them because of the heat and high power bills. Selling these (and my Cello Audio Palette) are my biggest regrets in my audiophile journey. 

I bought an FPB-300 in the late 90's and owned it until one channel started distorting last year. Given it's age, I decided to sell it as-is instead of getting it repaired. This was another great sounding amp, although I think I liked the MDA-300 better (different system, different room, so direct comparisons aren't possible). 

The obvious issue with these older amps is that they will need service at some point (more likely sooner than later) and some of the parts are no longer available so re-engineering can get expensive. 

I have a Krell KSA-300s. I got it from an estate sale along with a pair of Apogee Scintilla speakers for a price I could not pass up. The amp dates from 1994. A son-in-law of the deceased owner told me he never saw it turned on. So that means it could have sat for 20 years or so. Upon first power up the relays chattered. I removed the cover then decided to send it to Krell for service. Their service charge is $125/hr. It got a full re-cap and new relays and a little more. Including shipping double boxed inside a wooden crate cost me right at $2300. That was more than I paid for the amp/speakers combined. I must say it has been flawless since. I have the Krell KRC-HR preamp / KPC phono preamp / KSA-300s amp / Apogee Scintilla's setup in my performance/recording studio that has great acoustic isolation. No matter what genre of music I listen to, it still is a pleasure to hear everything properly.

I recently sold my KSA-50.  Had it for more than 15 years.  I loved the mid-range, but it was too bass heavy for long term listening, so it never got a lot of use. 

Listening to other Krells of the period, I felt all sounded similar.  Bass (and heat) like no tomorrow.  Impressive, but it wears on you after a while.  

Beautiful build quality.  

Norman

The KMA 100s ran class A up to the rated power. The amp always seemed a lot more powerful than 100 ways. They never ran out of steam. Getting to 100 dB on full range ESLs, no sub was easy. I suspect they kept going in AB mode. The power supply was huge.

KSA50, KSA100 and KMA100 monoblocks there were ones with internal chimney heatsinks that were fan forced and had proper amount of Class-A on them into 8ohms, KSA50 had 50w the KSA, and KMA had 100w

The other later ones with external heatsinks were just high bias Class-A/B 10-20 or so watts. Then there were the Plateau (sliding) biased ones, that never sounded that go to me.

I dare say these rare monoblock ones had some decent amount Class-A bias on them.
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Cheers George

I have some Vintage Krells (3). 2 of them have been recapped and serviced (KSA-200s - KST-100) I also have a KSA-250 that I have not yet gotten recapped but was checked for running operation when I bought it at a service center. These amps are the best for me with my Martin Logan ESLs and Montis. My take is that the Class A and power reserves, output transistors from them just is superior to other amps I’ve tried.

Currently I’m in love with my KSA-200s in my system. I have to say that the bias technology in the KSA-200s runs very cool, at full power or idling. I can say that the KSA-200s is one of the best out there, and the KSA-300s is even better if you have the speakers than can handle the extra power. I may some day get one of the KSA-300s for my collection. The KST-100 and the KSA-250 are the generation before the adjustable bias on the KSA-200s. They run very hot, and can heat up a room without AC. Oh, the sound though. I bought a recapped Mark Levinson No.331 and sold it and got another Krell. Mark didn’t really gel with the Martin Logans. Shame. It was the most beautiful amp I had ever seen. KSA-200s is supposed to be the most musical of all the Vintage Krells (KSA-300s too).

Yeah you’re probably right, they worked great in the 18 months or so I had them though. With a pending marriage and house costs, it was just getting too costly to keep chasing the high end. From the pictures I’ve seen of the insides over the years, they look surprising basic and possibly easy to repair compared to modern complicated units stuffed with surface mount devices. Are/were critical parts hard to source...Krell only? At the prices they go for now, I still find them tempting!

Spinaker you made the right choice. You get a lot more money for them before they blow then after. Every last one will blow it's output stage eventually just light an incandescent light bulb. But, they were a great performing amp. They certainly opened my eyes (ears) as to what was possible with ESLs. I discovered that ESLs had no problem going real loud and being real dynamic with the right amp. 

I too fondly remember the KMA 100 mono blocks. Gorgeous sound and my first real entry into the hi end world in the 80s. Had to sell them when I got married, which, upon reflect was the wrong choice.....

I owned Krell KMA 100s. They were wonderful amps. They "fried" at about 20 years of age. The semiconductors they used back then were not as temp resistant so they used a fan driven chimney set up. Fan drew air from the bottom of the amp and exhausted it on top. They warned you not to put the amps down on carpet. Anyway, Dan D'Agustino who not longer owns Krell really pissed me off on a preamp issue so I sold the amps to a fellow who thought he could fix the one that blew and given Dan's customer support philosophy I swore off his products entirely and warn others to stay away. 
My own philosophy is that a bank full of dollars is no fun. I am sure I will die with very little. My wife will get it all and she deserves every penny for putting up with me for all these years.    

Thanks John. Your experience is what I wanted to hear about. Nostalgia is getting to me. Have owned so many great pieces over 40+ years. It’s actually shameful. I know I could have stopped many years ago and had a great system that would be richly rewarding and a bank full of dollars! 

I bought one used quite a while back. The amp ran & worked great for a year, then fried. I sent it to Krell for repair. Worked for 3-4 weeks then fried. Sent back to Krell & they repaired for free. When it was returned FedX must have kicked it off the back of a truck. The whole inside broke loose. I told Krell my sob story & they offered to sell me a FPB300cx at dealer cost. I swooped the 300 up and have had zero issues for say a dozen years or so. Sound wise? Can’t say I could tell any difference, they are both bad a-- pieces of equipment. Both are built like Sherman tanks. I would never buy one that I had to have shipped. Even new.
I hope it helps, John