Krell FPB 400CX vs PASS LABS X-350.5


I'm moving up the ladder and have it down to these two amps. Any suggestions?? Should I go with the Krell FPB400CX or the PASS LABS X-350.5??

Speakers: DeVore Fidelity Nines
Preamp: Pass Labs X-1
Source: Esoteric X-03SE
Cables: Audiopath Silver 8 all around
roor
I found the PASS X250.5 to be noticably quite superior to the Krell FPB-300cx when compared side-by-side. I would assume that the same would go for the next models up. The PASS X.5 series is 5+ years newer than the old Krell FPB series. I found the Krell Evolution Stereo Amps to be sonically very competitive with the PASS X.5 (& XA.5) Stereo Amps.
I would do neither.

With the specifications of the Devore Nines, both amps under consideration are serious overkill.

If you're determined to buy solid state, then I'd look at the Pass XA-.5 series...either the XA-60.5 or the XA-100.5. Depending on your room size, the XA-60.5 would do nicely. If you have a large room, then the XA-100.5 would be recommended.

Frankly, I'd use a tube amp with the Devore Nines.
Ditto Tvad's comments. If you want to stick to solid state you could also consider the class A models from Plinius: SA-50, SA-100 & SA-02.... or Clayton S40 & M100
Good suggestions from Pdreher.
I agree with Tvad and Pdreher. Based on my experience with earlier Pass class-A vs AB designs, including older Threshold models, if the XA-60.5 is remotely close in price to the X-350.5 go for the XA. It will sound enormously powerful on the Nines and will have subtlety and nuance the AB amp lacks.

Happy listening,
John DeVore
Thanks a bunch, guys. I appreciate you taking the time to call me the other day, John. I picked up the Nines last week, and they are awesome. I just sold my Pass Labs X-250.5 and and have ruled out the krell FPB, so it will be the X-350.5 for now. I've found a good deal on the X-350.5, but someday plan to go up again to the XA-100.5's.

Best Regards,
Greg
I talked with a very reputable Pass Labs dealer and he mentioned that the XA-60.5 would be a different sound than the X-350.5 He said it would be warmer, and more tube sounding but the X-350.5 would have much more control and bass slam (he doesn't have any X-350.5's now, and isn't trying to push me one way or the other). I listen to mostly rock and roll, and complex sounding music at moderate to higher volumes. The XA-60.5's would probably do it with the Nines and be the best choice, but Pass agree's that I may want t a little more power than that - considering my taste. I actually started thinking the XA-30.5 would be the sweetest, but it wouldn't have enough UMPH for me. Pass warned me of this. I was thinking the XA-60.5 would do it, but have started to rethink that I should go with the XA-100.5's. I know these would smoke the X-350.5 but are much less expensive than the XA-60.5 or the XA-100.5's

Do you guys think the XA-60.5 would be more than enough?? Keep in mind, I hope to move up to the DeVore Fidelity Silverbacks someday.....(part of the reason for wanting a amp plenty big enough, and essentially all class A)

TVAD I went on a tube quest for about 10 years, and had dozens of very expensive tubes, and was rolling them all the time. I decided to make the change back to solid state a few years ago and have never looked back. I do aggree that they sound like nothing else, but for me the ease of SS is very appealing. I am in love with the Pass X and XA amps/preamps. Thanks for all your help. I will let you know what I decide to do. I'm going to try and get both the X-350.5 and the XA-60.5 in my home together at the same time to properly compare.
I think the comment about more control and bass slam are nonsense. I listen
to primarily rock, and I can tell you the XA-60.5 have better bass control,
slam, (and tonal balance) than any amp I have owned, including Bryston 14B
SST and Moscode 401HR.

It's all about the speaker match, the size of the room, and the volume at
which
one listens. I listen loudly in a 24X19 foot room.

Why don't you contact Reno HiFi and ask Mark for an in-home XA-60.5
demo.
Then, you can compare the amps for yourself in your system and bypass the
speculation.
>>05-17-09: Roor
I talked with a very reputable Pass Labs dealer and he mentioned that the XA-60.5 would be a different sound than the X-350.5 He said it would be warmer, and more tube sounding but the X-350.5 would have much more control and bass slam<<

He's correct on the different sonics but way off on the control and bass slam. I recommend he listen to them side by side.

Dealer disclaimer
I agree with Tvad, and tend to lean heavily towards quality vs. quantity when it comes to amps and audio gear in general. The Nines & the Silverbacks are quite efficient, and should match well with the XA-60.5, even with your musical tastes. Would be interested to hear John DeVore's thoughts / preferences between the two amp in question.
According to the latest stereophile measurement XA-30.5 clips (1% THD) at around 100W. XA-30.5 or XA-60.5 may be just fine for your use. FWIW I use First Watt F5 at 25Wpc with my Focal Electras in 15 x 20 room, and I have never felt I needed more power.
Would be interested to hear John DeVore's thoughts / preferences between the two amp in question.
Pdreher (System | Threads | Answers)

John Devore has already commented above:
if the XA-60.5 is remotely close in price to the X-350.5 go for the XA. It will sound enormously powerful on the Nines and will have subtlety and nuance the AB amp lacks.

Happy listening,
John DeVore
Jldcat (System | Answers)

More than anyone, the company owner should know how an amp would perform on the Nines .
Tvad - my bad... at the risk of sounding like a kiss ass, I agree with your last statement
Do you all think the smaller Pass Labs XA-30.5 would be enough for the Nines. My room is 14' x 24'?

Would that be a better choice than the X-350.5??
I think you should contact Reno HiFi and arrange an in-home trial and bypass
the speculation.

I also think John Devore has already mentioned what amps he believes would
work well.

In my system and room (93dB speakers), the XA-30.5 was very close, but
wouldn't quite get the job done in the volume department. If you audition the
XA-30.5, you'll know how the XA-.5 series sound on the Nines, and then you
can move up to more power if necessary.

IMO, any of the XA-.5 series Pass amps are better choices than the X-350.5
because of their more refined sound.
Well I actually had both amps side by side in my system for a while and the Pass X350.5 is better in every aspect than the FPB400CX.

The X350.5 should be compared to the Krell EVO402 and then they are very close. I had the EVO402 as well and it does sound very similar to the Pass X350.5 but at 1.5 times the price.

For price / performance ratio the Pass is the best.

The FPB700CX is much better than the 400CX and would come close to the Pass X350.5. The 700Cx might even have a little more bass slam.

Peter
I did a head to head audition between the X-250.5, the X-350.5 and the XA-30.5.

The smaller 30 watt class A XA-30.5 smoked both of the X models, and has more than enough power for my DeVore Nines in a large room.
Thanks for the report, Roor.

How would you describe the combination?

I recently read Fremmer's Stereophile review of the Devore Silverbacks, in which he mentioned they were slightly "cool" sounding due to a recessed midbass (although he mentioned he preferred this over a plump midbass).
The DeVore Nines/Pass XA-30.5/Pass X-1/Esoteric X03-SE combo does not sound cool at all in my opinion. I would say very slightly warm "ish"; yet smooth, and neutral. Correct I guess would a good description. Dead quiet with more soundstage depth than the Pass X-model amps.The Pass Labs XA amps are killer.