Krell KSA 300S or FPB 300?

Hello all on a-gon,

I'm looking to get into some Krell amplification. Right now I'm considering the 2 amps above. I would like to get some of your expert opinions as to which ya'll prefer and which you would recommend. I would also like to hear why you prefer & recommend your choices.

I'll provide some of our associated equipment without getting overly detailed...

Amplifiers: Musical Fidelity KW500 (Selling) & Legacy-Audio Monoblocs
Speakers: Infinity Prelude MTS' & Legacy-Audio Focus
Digital: Esoteric DV-60 & Marantz BD8002
Analog: TNT IV with mucho upgrades
Phono: X-Ono
Preamp: Legacy-Audio NexStep. Preamp replacing the NexStep: Krell Audio/Video Standard from a super fine fellow a-goner. Greg, thank you again for the AWESOME Krell!

So there's the condensed version of our equipment.

As far as musical taste... my wife and I enjoy the following. In no particular order...

Big Band
We'll... actually we like just about all genres except OPERA!!!
We also like our music as low as background and all the way up to concert levels whilst enjoying Several-Frosty-Beverages.

Oh wise one's... please grace me with your honest opinions.

I hope that gives you's guy's enough info to make a choice/recommendation.
If any other information may help you with your recommends please let me know.


hello, it is a tough call, i had owned both before, i think they sound pretty close . but i like the KSA a little more in my personal taste on sound,, FPB is very clean(may be a little cleaner than KSA,) but KSA seems more natual in mid, personlly issue, FPB failed me on one channel by no reason??. so i am not crazy about the FPB any more, good luck on your searching
I would pick the KSA as well. From reviews of the old days, they mentioned that Krell just bump up the output power rating by using a different measuring method for the FPB and newer models. So the KSA is the real Krell.

I still keep my KSA250 even though I do not have a use of it for the last 6 years. It is just a piece of art.

Of course, for either model, you may need a tune up from Krell to keep it in top shape.
I owned the KSA200S & now own a FPB300cx. I feel the opposite of the above opinions, but not by much. The FPB300 is definatly built better and being newer is the one I would recommend. I also believe the FPB version is a little bit "darker" sounding than the KSA was. A smidgeon more sound stage and backround I reckon. Either way, I believe you will enjoy the units.
Note: FED X dropped my KSA during transit coming back from Krell for service and scrapped it. I HIGHLY recommend shipping by Ocean Air which is what Krell recommends. That is why I ended up with the FPB as I had to buy a new one to replace the FedX screw up.
Enjoy, John
I owned a KSA-200S and upgraded to a FPB300. I thought it was no contest in favor of the FPB. Compared to the FPB, the KSA sounded undymanic and sounded rolled off at the frequency extremes in my system. The FPB sounded so much more natural at every frequency. The bass of the FPB was just as tight, but much more nimble.

IMHO, the Krell KSA "S" series amplifiers were one of Krell's worst efforts. I would take an older KSA150, KSA250 MDA srries etc. over any of the "s" series amplifiers. I also think that the FPB was much better that the "s" series.
I'm going to have to second Brf's response. Get an older Krell KSA non 'S' or an FPB.

BRF & Perfect_sound...
What is it that you prefer the older KSA's over the S model? What's yall's take on that? Isn't the only difference that one offers balanced operation?
By the way all, I'm actually leaning toward the KSA as I like the tank like built of that amp.
Keep the opinions coming. It really helps to hear from those who have owned one, especially those who have owned both.
I really wish it was feasible to audition them back to back. The only way that would be possible, for me in Wyoming, would be to purchase them both, compare, and then sell the one that doesn't pass my mustard test.
Jsd... ouch!!!

I'm really enjoying the addition to my system (Legacy Helix, PS Audio Perfect Wave DAC and transport, ARC Ref 3. See my system if interested.)of 1 pair of MDA-300s and 2 KSA-250s. I've listened to KSA 250s at a friends house for years. They provide outstanding bass, a tube like midrange (vibes sound outstanding), and a liquid, unfatiguing, extended treble. I've not listened to the MDA-300s for anything else but bass, (that's what they do in my quad amped sytem) but I did audition them vs. the KSA 250 and liked what the MDA-300s did to the bass (cleaner, more transparent). Amps I've listend to before are Acoustat TNT 200s, Hafler DH-500 and 200s, Threshold, Brystons not the newest versions, Levinson #336, #436s and #33s, Pass Labs (I forget the model), Krell FPB 350 monos (I think that's right), and various amps from ARC. My conclusion, even if I have to do a complete recap or overhaul, which requires sending the amps back to Krell, compared to the new stuff in today's market place, the KSAs are really bargains.
A couple of caveats, heat (they run class A,that's why they sound so good), no linked off/on or warmup switch, sharp heat sinks, and weight.
Hope this helps your decision.

A local buddy just sold his FPB200 and purchased a KSA100s. He likes the midrange and topend better on the S series.
The "S" series stands for Sustained Plateau Bias technology which was first introduced in the Krell Audio Standard. This is a variation on the "sliding bias" idea, except that bias is changed in discrete steps rather than continuously. A so-called "anticipator circuit" at the amplifier's input responds very quickly to an increase in signal level, so that, by the time the signal reaches that output stage, the output will be biased to class-A.

The KSA S-series amplifiers did not have have the same deep bass as the former KSA / MDA series. Some felt that this was due to the anticipator circuit and the way it was employed in the s-series amplifiers. I found the S-series amplifiers to sound sterile and less dynamic than the former KSA. I am not a huge Krell fan, but I could live with a KSA 50 or a KSA 250 amplifier. If you have the space and are not too concerned with the heat issue, I would go for a KSA 250, invest in a recap (if and when needed)and you will have one of Krell's classics. People still ooh and awe over the performance and sound of a Krell KSA 250, but rarely do you hear them speak of the KSA 200"S" in the same regard. Just my 2 cents.

I noticed that the 250 does have balanced capabilities. Something I prefer.
As far as capping... do you mean replacement of the original, possibly drying out, capacitors or are you talking upgraded caps?
Sgr... as far as heat goes I don't believe that will be much of a concern. I've heard of how hot they run. They'll be located in a position where they're by themselves and not in a stand configuration. I was also looking at Parasound's Zbreeze fan for some extra cooling for the Krell. Looks like a pretty nice product.
Sure want to thank all for their expert advice. It so nice to have a-gon to go to for opinions from those who are so knowledgable in this hobby!

The KSA 250 has balanced inputs and SE inputs. The heat generated by the amp has a tendency to potentially dry out caps, therefore, requiring replacement. With respect to heat, the amp does not need any additional cooling, it just raises the room's ambient temp.
A cap replacement at Krell could cost up to $1500.00 including shipping. I've seen a video on how to replace the caps in KSA 250s on the internet and I believe it is on U-Tube. A Google search should bring this up. We have a great tech service in St. Louis called Alpha Tech, Mike is the tech person there, and I'd trust him to perform any service on the Krells and evaluate anything that needs done. There phone number is 314 645 5250. Before shipping to Krell, (although this is probably the best option, but also the most expensive,) I'd see if you have a good tech service locally.
Sgr I have used Alpha Tech. They do good work and they are the ones I speak of in my oast previous posts concerning Levinson amps.

I guess everything is subjective but some people think the S series is sweeter especially in the midrange. My buddy used to have a KSA 250 and likes the KSA 200s better.

Will find out what a cap replacement would cost from Alpha Tech & Krell. Will try and get a quote from both.

If I could get a step by step instructional on how to replace the caps, I could do that myself... used to build pc-boards for the Dragon Missile System (For the Army) back in my late teens @ McDonnell Douglas. I would also need a schematic and parts list. That's a viable option except for the testing and settings of the amp. Have no idea on how to do the bias adjustment, dc-offset, check oscillation and such. No oscilloscope and no experience as how to read them!

Looks like I'll be checking You Tube.

I can't find ANYONE locally who could work on this amp. We don't have a single electronics repair business here in Laramie. The closest is Ft. Collins @ about an hour South and then Denver @ about 2 hours South. Bet I could find someone in Denver. They have a few High-End Audio shops there.

My only worries would be that if someone other than Krell did any work on the amp would Krell still work on the unit if it were ever in need to be returned to Krell for repair? Musical Fidelity won't do it!

I have to share my experience although there is a lot of good response to this I have lived owned the KSA-250, 300S and FPB 300. My first Krell amp was the 250 and I loved it but then thought newer was even better. I sold the 250 and bought the KSA-200S only to have lost the major bass slam that I loved from the 250. After talking with krell, they said that was because of the transformer size and I should have got the 300S. I then sold the 200S only and bought the 300S and was rejoicing once again. The 300S was much cleaner from mids and into the upper frequencies, that was my impression and that the 250 was a bit "grainier". I loved that for a few years and started thinking "what if" and decided to buy the FPB300 but had to sell the 300S first to afford it. I did that and got the FPB300 and although it was even more refined sounding I felt it lost the "amplified" sound for rock/metal and was really sorry I sold the 300S. I tried to live with it but just couldn't and sold it only to buy my current 300S that I am living happily ever after. The bottom line is that I found my “cup of tea” for my liking and won’t part with it now. Obviously try to audition before you buy but the good thing is the resale on most Krell is not that bad. My system is Krell AVS, DT10, B&W 802N with all Purist Audio Venustas cables.
I had to put In my 2 cents. I have owned the ksa 250 many 200 and 300s amps. Fpb 650m . I owned audio standards. Fpb 600. I have owned three of them. I currently own a ksa 300s and fpb350m monos. The s series has a very special sound. I would much rather own a 200s or a 300s than a 250. The 250 is a great amp looks and sound. The s series amps are much cleaner and more musical. The 300s Is by far the best buy In audio. If you go fpb the monos are the way to go. The have more control and seperation than any of the other amps. The s series Is very musical and fun to listen to. I really never warmed up to the fpb 600 . It Is very clean Incredible control on the bass but never drew me In. So my opinon go with either fpb 250m 350m 650m Or the 200s 300s.
Krell1 you have hit the nail on the head. people keep comparing the 200s to things but the one you need is the 300s. Completely different from the 200s and the boys at Krell weren't lying to you. The tranformer size is amost double which gives you bass and is especially important with difficult to drive speakers. The current controls the woofer panels, if you don;'t have enough the speaker will sound sloppy and muddy on complex passages. Lok at the weight of the amps. The 300s approsches 200 pounds while the fbp is only about 150.
Go for the 300s. it is also the better buy as many people are misinformed. Completely different from 200s.
>>>If you go fpb the monos are the way to go. The have more control and seperation than any of the other amps. The s series Is very musical and fun to listen to. So my opinon go with either fpb 250m 350m 650m Or the 200s 300s. <<<

Do you have any experience with the FPB-350MCX ? How does it compare with the FPB-350M that you have ? Also is it as musical as the S series and the KSA-300S ?
I have the best of both worlds. I have both ot these amps. I use the KSA for the bass and the FPB for the mid/highs. (I use the KBX to divide the signal)
Any questions, just ask.