Krell FPB 350Mcx's enough for THIEL 7.2's + CS5i's


I am hoping THIEL owners have some feedback regarding matching Krell Amps with these specific speakers. I have both the 7.2's and the 5i's. The 7.2's are in my primary dedicated listening room, and the 5i's are in the theater. I'd like to buy Mono's, but I am only running across the 350's for sale. I have concerns that these are enough for the low loads presented by the THIEL's. I'd like to have an amp that can handle either speaker so that I can swap them periodically and enjoy the subtle differences. Pre-Amp = Krell KCT, Let me know what experience you have with these speakers and Krell amps.
davidstingray
Hi David,

i suspect the 350mcx will be fine in nearly any but the most extreme scenarios. It has been many years...i have auditioned the 7.2s with Krell KSA 250 and it did clip...but the room was 30x20x with 12-14' ceiling, and the guy was literally playing it at concert levels.

Your Krell 350mcx monos should be substantially more powerful than ksa250, substantially more. so unless you plan on playing them in a barn at concert levels, i think you will be fine.
I have a client that drives a pair of Revel Salon 2s with a set of the Krell FPB 350MCX's with no problem. The Saolon 2s are a very extreme hard load with a low sensitivity output. The Krell mono amps drive the Salon 2s speakers with a ease and with a very impressive sound. I am willing to bet those 350 monos sound good with the Thiels 7.2s
Sounds like you guys have confidence. So the 450MCX's would suite me just as well and even better. I had heard that the extra headroom in the 750's made a difference even at the lower end, and provider greater speed.

Too bad I just missed a pair on eBay. I know there are some 350's for sale now, but I'd rather throw that much towards the 450's. Good problems to have I know.
Hi David,

If you want 450mcx monos, then you're done. Talk to Jack Tozzi at Spearit Sound in MA. They are a Krell dealer (i think), and have a pair of 450mcx monos for $8,500. I have bought 3 big pieces of equipment from Jack over the last 12 years, and people at CJ have the highest regard for him. He is one of the class acts in this business. Please tell him i say hello. If you want an intro, i am happy to email him and cc you. I have done this for a few people. He is great. BTW, i have 0 affiliation with Spearit Sound...i just like to give people referrals when they provide great service.
BTW, i asked Jack about the diff once between the 450mcx and the 750mcx...he said they were bloody close, and it would be up to your speakers to even tell the difference. In your case, i think you will find the 450mcx monos kick some serious a-.
Interesting. I think the 750's would be a big push for me. I probably wouldn't stretch the speakers out enough to notice the difference. I do like the idea of not having to buy another set of amps though because i'm "wondering" what the 750's would sound like. I was even considering the McIntosh 1200 mono's at a slightly lower price point then the 750's.
David,

I think if you wish to ensure you've just that extra bit of power, the 450mcx's should be sufficient for anything but the most extreme rooms and volumes (which would probably risk making you permanentenly deaf)

And for those who doubt that it can happen, i know some who wears 2 hearing aids now after an all-day concert-volume session with a pair of Alexandrias...he woke up the next day with very little hearing and it never came back...
The listening room is 18 ft wide, by 20 ft deep. The Theater is 18 wide by 24 ft deep. Good size rooms, but not enormous.

Got a little freaked out by the comment above RE: volume. I should probably do myself the favor and undercut the capacity. Can't use it if it isn't there. Thanks for the feedback.
Very nice sized room. You should be fine with either set of amps...i would still go for the 450mcx if you have the option... strangely, what i found in my own system is that the better the equipment, the less distortion, while i can play super-loud and not realize it...because the signal is so clean...i also can enjoy at super-low levels and not lose any detail, nor any bass...i've never had this in 20 years. So if u end up with 450mcx, who knows? you might turn it down instead...but always nice to know you can turn it up for theater...and never miss an explosion!
I wanted to circle back on this thread and let folks know that I ended up going with the Krell 650M's. Timing is everything, and these amps were the right amps at the right time and at the right price.

I am extraordinarily happy with them as I continue to re-explore my music collection. Power wise the amps drive the CS 7.2's effortlessly. I have not had the opportunity to move the CS5i's over to the listening room, but I am looking forward to it at some point. Right now I am focusing on upgrading my speaker wires.

Feel free to drop tips on wiring.

Cheers,
David
Congrats! Fantastic news! Enjoy...they are sensational amps and should provide you with tremendous sound for years to come.
Thanks Lloyde. I really feel fortunate to own these amps and have them in my system.

They are truely remarkable and have show me things that I didn't think were possible audio wise.

Everything that I thought were components of reflection and noise in my room have been removed. They were products of my amps in disguise.

David
Great stuff, David. It is remarkable what can happen when you put a piece of SOTA equipment into your system. It improves in ways you were not expecting, and it reveals subtle aberrations you did not quite hear were there...but only appreciate after they're gone! Enjoy!

Now what's your next big upgrade? ;)
The next big upgrade is going to either be a higher quality CD player, or perhaps a turntable. I currently do not have an analog source, so I might have to make the leap and give it a listen.
Very nice mono's, I heard them with Sonus Faber Amati. This was the only time I heard the Amati well controlled. Control of these amps are very good!
DAvidstingray...sounds good! What CD player(s) are you considering? I am not an analog guy so unfortunately can only sit on the sidelines there and watch the game.
Congrats on the amps. I used the Krell 650M amps with the 7.2s for a couple years and was very happy with that pairing. Enjoy!
@Tom - Did you get rid of the Krells or the THIELs? or both?

I have been so impressed by the THIEL 7.2's. They have continued to improve with every component upgrade I have made over the past three years. They do an extraordinary job at reveling system limitations, recordings, etc. in my opinion.

@Lloyd - I am looking at Krell's specifically, however, I am going to have to wait and catch up on things before I pull the trigger on another acquisition. I have also been looking at a couple of the Mark Levinson units, but I am not as familiar with the product lines as I am Krell. For the time being, I am going to live with RCA's out of my current player. Oh the humanity.
I really like Krell with Thiels, though others seem to like Levinson with Thiels, I'm not amongst them.
As far as getting into vinyl; I'm of the opinion that unless you already have a large collection of vinyl, your time and money might be better spent elsewhere.
Unsound - not true - there is plenty of used vinyl and quite a bit of new pressings also. I have several stand alone vinyl retailers near me. A good record cleaning machine is all you need. I very rarely listen to digital anymore, bores me to tears. Go for it!
Pops, we may disagree on this one, but comparatively speaking; what I posted is not untrue.
I'm aligned with Unsound on this; Krell and Thiels are an excellent match (KCT,400cx and CS6). This is my tenth year of owning this combo and it still sounds better and better as the years roll on by. But I listen to vinyl as often as digital and thoroughly enjoy both.
When I owned the Thiels I used Ayre V-1xe, Bryston 7Bsst, Parasound JC-1s. All well rated amps, until I bought the krells I really hadnt heard the Thiels at there best. (at least when compared to the other amps I owned)
I have heard the 3.7 sound wonderful with Hegel amps at RMAF a couple years ago too. If I used Thiels again they would be a second option after Krell.
@Steve - I have heard that the 400cx is a fantastic amp and highly rated. I am amazed that you have held onto the CS6's for so long and didn't make the jump to the 7.2's. Have you ever had the opportunity to listen to the 7.2's against the 6's?

@Tom - congrats on the YG's. Interesting move to all tubes. Was this to add a warmer sound? I have yet to experience a tube amp against the THIEL's. I need to find some one in my neighborhood who would be willing to demo.

I also had a Bryston running against the THIEL's and thought highly of the sound. The Krell's really are a step above, but the Bryston is a real bang for the buck and has a tremendous sound in a small package. As a matter of fact, I moved the Bryston over to manage the L + R channels in my home theater.