Best Krell amp to use for ML Sl3's? FPB? or older KSA series?

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gordonmenninger

gordonmenninger

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ok, i have the upgrade bug once again... Now the victim: my multichannel amp (sunfire cinema grand, 5 x 200. Used for center and bi amping of the SL3's).
This amp has done well over the past years but after buying the Krell S1200U processor 18 months ago, i think that my amps are the weakest link in my system. I have extensive room treatments / bass traps, etc and my room sounds about as good as it can... I like to really crank my system but it does sound a bit harsh at louder levels...I watch movies but we also watch alot of concerts and of course i listen to music on the system.
Obviously we all know that the SL3's need a beefy power amp to drive it to satisfactory levels. I am trying to decide between McIntosh stereo amp or a Krell amp on the used market. I have somewhat ruled out the McIntosh amps due to them not doubling power as impedance halves... I would love to get a used Krell fpb 300 or higher for the LR channels and use the Sunfire for Center and rears.

What are your suggestions? I have yet to find out exactly the difference between the "older" and the "newer" fpb series that changed cosmetically - can anyone enlighten me? Would the fpb 300 be powerful enough as it will be putting out 600 watts into 4 ohms? ALso I am not crazy about not having the same brand of amp for my center (Theater i)... I appreciate any suggestions!

Oh, for what it's worth, I have 2 x JL Fathom 113 subs and listen to my music using a squeezebox with great results!

gordon
 
gordonmenninger said:
ok, i have the upgrade bug once again... Now the victim: my multichannel amp (sunfire cinema grand, 5 x 200. Used for center and bi amping of the SL3's).
This amp has done well over the past years but after buying the Krell S1200U processor 18 months ago, i think that my amps are the weakest link in my system. I have extensive room treatments / bass traps, etc and my room sounds about as good as it can... I like to really crank my system but it does sound a bit harsh at louder levels...I watch movies but we also watch alot of concerts and of course i listen to music on the system.
Obviously we all know that the SL3's need a beefy power amp to drive it to satisfactory levels. I am trying to decide between McIntosh stereo amp or a Krell amp on the used market. I have somewhat ruled out the McIntosh amps due to them not doubling power as impedance halves... I would love to get a used Krell fpb 300 or higher for the LR channels and use the Sunfire for Center and rears.

What are your suggestions? I have yet to find out exactly the difference between the "older" and the "newer" fpb series that changed cosmetically - can anyone enlighten me? Would the fpb 300 be powerful enough as it will be putting out 600 watts into 4 ohms? ALso I am not crazy about not having the same brand of amp for my center (Theater i)... I appreciate any suggestions!

Oh, for what it's worth, I have 2 x JL Fathom 113 subs and listen to my music using a squeezebox with great results!

gordon
Click to expand...

Go with a Krell TAS. I have it with the S1200U and Summit X/Stage set up and sounds good. Should be able to get a good deal off ebay or dealers like Spearit Sound who are an authorized dealer and also sell used Krell gear.
 
gordonmenninger said:
I have somewhat ruled out the McIntosh amps due to them not doubling power as impedance halves...
Click to expand...
Well, dismissing an amp just because it does not "double down" as impedance halves is kinda short-sided. The McIntosh amplifiers don't double down because they have autoformers to deal with impedance swing at the speaker interface. There are LOTS of tube amps which don't fall into the doubling down category, but they are MUCH more musical than the SS counterpart.

I would love to get a used Krell fpb 300 or higher for the LR channels and use the Sunfire for Center and rears.
Click to expand...
I've known a few very musical systems using Krell FPB and Logans. That said, I am partial to the older KSA series of Krell.
 
I am using Sequel II's in 2-channel mode.
My amp setup is a Conrad Johnson Classic Line Preamp with a classic Krell KSA300S power amp (2x600w @ 4 Ohms).
Sounds glorious across all frequencies and the volume level available would remove all doors & windows if my ears didn't bleed first!!
Kenni
 
Very interesting thoughts here! Thanks! I did not know that there was so much love for the KSA series over the FPB series! I always thought that the FPB was the one to strive for when pairing ML's with Krells! Anyone else care to share their experiences with this? thanks so much!
 
Prefer FBP

Hello,

had KSA100, 200S with my Logans. The FBP was a big step foward compared with the KSA(s).

Actually I drive my Summits by means of an FBP200. I prefer the "smaller" FBP's over the bigger ones and even the EVOs. The 200/300 FBP's are very musical and sound warmer than their big brothers without compromising resolution and imaging.

Br
Johann
 
One of the very first ML systems I listened to was powered with the Krell KSA amps. I am not a huge fan of the newer Krell line, but the KSA amps were awesome.

Erik
 
It's common knowledge that the older ksa series sounds significantly better than the newer 'fbp' stuff. I thought everyone knew this. Ken kessler recently reviewed an old krell ksa 50 and gave it a "state of the art" rating basically saying that it was head and shoulders above the newer krell gear.
 
Dan Osib said:
It's common knowledge that the older ksa series sounds significantly better than the newer 'fbp' stuff. I thought everyone knew this. Ken kessler recently reviewed an old krell ksa 50 and gave it a "state of the art" rating basically saying that it was head and shoulders above the newer krell gear.
Click to expand...

Hmmmmmmmmmmmm... I like Ken a lot. But in this case, for a KSA fed with a passive pre, using what is supposed to be their ideal partner (Apogees), I can confidently state that it was completely trashed by my 211 monos. See the link in my post.

I'd rather listen to a Behringer A500 (check the price) than the Krell KSA 50 driving refurbished Apogees. A Caliper owner agrees too - and he owns the KSA 50.
 
KSA and FPB amps are both great, FPB has more regulation ( more stuff that can break).
All FPB and KSA's are relatively old the non cast FPB's are over 10 years the KSA's even older, that is a long time for class A amps, they run hot!! I bought my FPB 600c new 12 year ago and it has served me well on CLS's, Statement E2's and lately MBL 101 E's, plenty of power and control. Recently i had all capacitors replaced and the CX modification made and found out how much the old girl needed TLC !! If you go FPB, try finding a CX model, they are newer, and the upgrade sweetens up the treble. God luck!
 
Thanks for the great info! I am leaning towards the KSA 300s right now after doing extensive research on it. I love the massive look of this amp and alot of people have great things to say about it and call it one of the classic Krell amps when they still went all out with their designs!
not to hijack this thread, but I also hear alot of talk about this or that Krell amp has alot of bass slam / definition, etc... Does this technically matter in my setup since I cross my SL3's over at 80 hertz and feed everything below to my 2 beloved Fathom subs? I know this would be important if I ran my speakers full range but that is not the case. Can anyone clarify this for me?
 
gordonmenninger said:
Thanks for the great info! I am leaning towards the KSA 300s right now after doing extensive research on it. I love the massive look of this amp and alot of people have great things to say about it and call it one of the classic Krell amps when they still went all out with their designs!
not to hijack this thread, but I also hear alot of talk about this or that Krell amp has alot of bass slam / definition, etc... Does this technically matter in my setup since I cross my SL3's over at 80 hertz and feed everything below to my 2 beloved Fathom subs? I know this would be important if I ran my speakers full range but that is not the case. Can anyone clarify this for me?
Click to expand...

Hello,
While crossing over at 80hz will help, it does not help nearly as much as it would if you were using conventional speakers. Electrostatic Hybrids like your SL3's are at their most demanding at the upper frequencies which is the opposite of box speakers.

All that being said, a KSA-300 will have no problem driving your speakers. It would be ideal to find one that has recently been sent to Krell and has been recently Serviced as has been said Class A Amplifiers do need maintenance when talking about amps that are well over a decade old. I too love the KSA Series and have often thought about getting one. A Plinius SB-301 or an older SA-100, 102 or 103 would be another good choice and would be newer as well. You also get to choose between Class A or Class AB Operation by the flick of a switch with these.
Cheers,
JJ
 
If you plump for a ksa then the only downside i can think of is that a lot of the electrolytic capacitors inside it will probably be nearing the end of their life. Best thing would be to replace them for the finest currently available which would be jensen capacitors (shouldn't cost you more than a few hundred dollars though).
 
gordonmenninger said:
Does this technically matter in my setup since I cross my SL3's over at 80 hertz and feed everything below to my 2 beloved Fathom subs? I know this would be important if I ran my speakers full range but that is not the case. Can anyone clarify this for me?
Click to expand...
YES, it does matter!! The Krell KSA and Pass amps excel in the bass to lower midrange region moreso than most other amps. Keep in mind that the deep male vocal range hovers in around the 200Hz range and won't get "smeared" with the Krell. If you go with the KSA300, I'd venture to push the crossover freq down to 65Hz instead of 80Hz.

Good Luck,
Spike
 
ok folks - I have made a decision: I just agreed to purchase a Krell KSA 300S in very good condition that had the full recap service done at Krell factory recently! I have read all the suggestions here and on Audiogon and think that this will be the best match for my SL3's! I just ran a dedicated 20 amp line just for the amp so I am ready for my new beast! I will be picking it up next week! I will post pics when I get my new baby home! Thanks everyone for your great suggestions as always!
gordon:rocker:
 
Update: I am heading to NY state to pick up my "new" Krell KSA300s on thursday. Full report to follow as soon as I transport the beast home with my heavy duty SUV and get it hooked up and dialed in! Hope I don't break my back!:music:
 
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