New CAT JL5 KT-120 based 100wpc Stereo amp...

[cmalak]

Originally Posted by Puma Cat

Not cranky, Cyril...that is a stupid design anyway you look at it.

Stephen...just teasing you. I agree...not well thought out from an ergonomics/practical installation stand point. Hope all is well.

[Puma Cat]

No worries, Cyril!

[peterspartan]

I am not concerned about Industrial design attributes but rather am far more interested in sonic excellence (there is a reason the the connections are were they are - to be as far away from the tranny as possible).
As for fitting it into a rack - I've designed and will fabricate the rack to suit the amp.
I'll provide some feedback once landed and run in - and pics of my completed rack.

[analog brother]

i like it too.
much scaled down version of big brother which is like having a furnace in the room.
please keep us updated.
thanks!

[chops-tube]

Originally Posted by peterspartan

I am not concerned about Industrial design attributes but rather am far more interested in sonic excellence (there is a reason the the connections are were they are - to be as far away from the tranny as possible).

I was thinking either keeping connections away from tranny, OR keeping connections within the amp from input to output as short as possible.

[ronenash]

Also, I cannot understand why use 4 KT120 tubes to get 100w power when you can use only two and that's using them conservatively. Makes no sense to me. If you are going to go with 4 KT120 output tubes per channel at least get a good 200w out of it.

[Elberoth]

You need to run them much harder to get those numbers. Jadis is another company that runs them this way and their amps sound really great.

[Esl Mike]

I can see why the other failed on the WAF. This one does, too. Ken Stevens needs to go to industrial design school, as he does not understand clean and practical industrial design. That looks simply ridiculous with respect to the speaker cables, interconnects, and the position of the cable jacks and binding posts. Big speaker cables coming off the middle of the side of an amplifier? Interconnects that plug in on either side of the front? Gimme a break! I wouldn't have it for failing the PCAF as well. Reminds me of some of the preamps where the IC's have to be inserted vertically.

I must preface this by mentioning that I’m a long-time CAT amp owner and as such, I am quite biased. However, neither I, nor my wife are even vaguely concerned about a piece of equipment’s aesthetics. While I realize that the WAF is oftentimes an important point, fortunately it has never been one for me, nor my beautiful bride! Because of my wife’s appreciation of my passion for accurate in-home audio reproduction -- in a marriage closer to a golden one, than silver one -- an equipment's looks, has never been an issue for her!

Previous CAT amps (JL1 monos, JL3 monos and JL2 Stereo) have not been rack mountable due to their 190 pound each, weight range and size. The new JL5 is only a "mere" 80 pounds. So, perhaps, one may want to slide this one in a rack, so I understand your point. But this is an amp to be on its own; on a floor stand and really isn’t an amp to mount in a rack. This is especially the case when it’s heard!

Also, I cannot understand why use 4 KT120 tubes to get 100w power when you can use only two and that's using them conservatively. Makes no sense to me. If you are going to go with 4 KT120 output tubes per channel at least get a good 200w out of it.

As I’ve learned over the years, sense and this hobby rarely correlate. It’s an understatement to say that CAT amps are overdesigned and their raw output is highly underrated. All you need to do is listen to the authority, finesse and drive provided by a CAT amp, to understand that the end result, is all that is needed to make sense out of the amp’s aestecic and electronic design choices.

The original JL1 monoblocks had (16) 6550’s and were rated at 100 watts each. However according to 2004 comments by Ken Stevens:

“The development of the CAT JL1s was mainly done using the older MBL101B, which at 78db, is even lower efficiency than the current model. Not only is the 101 very inefficient, it also has an impedance curve which can only be described as highly unusual -- actually bizarre would be a better description." "It is EXTREMELY difficult to drive."

An additional 2004 quote from Ken Stevens’ talks about his amplifier design and the tube compliment this way:

“A couple of people have asked me what makes the JL3 (and older JL1) capable of driving difficult loudspeakers when more "powerful" amplifiers cannot:”
“- Huge output transformer -- at 55 lb. bigger than any other amps output transformer (and much bigger than the 10-12 LB transformers typical of 150 watt tube amps). This means that this transformer runs at a fraction of its capability even at bass frequencies and even at full power for much better magnetic linearity.”
“- High turns ratio in transformer - the transformer could be driven by 2 pairs of output tubes to achieve the same power rating, but we use eight pairs (four in the JL1&JL2) to achieve the same power.” “This means that the load impedance - and variations of same - are reduced by a factor of four times versus similar triode amps from other companies.” “Obviously this makes the load less difficult for the output stage tubes.”

Suffice it to say that when I drug my first pair of CAT’s home to audition them against my Mark Levinson 336 350/Ch stereo amp, the CAT’s took my Soundlab full-range stats to a place they had never been! They not only drove the Soundlabs, they “controlled them” unlike the Levinson or Parasound Halo JC 1 monoblocks at (400W/Ch.) that I brought home with the CAT’s. The CAT JL1’s at 100 Watts/Channel did a controlled drive tap dance with SET finesse, on both these amps. And while the Levinson and the Halo may not be your cup of tea, they are anything but slouches. So, as far as I’m concerned, whatever aesthetic design decisions and tube complements make the CAT’s meow and purr like a kitty, but roar like a lion, they're quite ok by me!

If the new JL5 performs and sounds like its larger siblings, how it looks or how many tubes it has, is irrelevant! Discovering a push-pull amp with the drive of a monster amp, but the finesse of its SET brethren, is a real find and one of the few components in this hobby that are keeper's for life, and that’s how I view my CAT JL3’s.

Audio Room Equipment other than the Soundlabs & CAT’s:
Wavelength Crimson USB DAC; Mac Mini PC; PureMusic Software; iPad Remote; Galibier Quattro Turntable with Tri-Planar Tonearm and Dynavector XV-1s Cartridge; Aria Audio WV5-XL Full-Range Preamp; Synergistic Research Cables; Purchased & DIY panels, absorpting the Soundlab's backwaves (very important in my room for enhanced imaging and soundstage).

[Masterlu]

Esl Mike... Welcome to AA!

[gino22]

Originally Posted by tdelahanty

Mechanical design is not the only area where CAT amps fall short, I've worked on them, personally I'd avoid them, far too touchy.

Well, why is that? Can share in detail? I've been watching CAT gears and about to deal the SL-1 Renaissance + JL5 Combo. Need your advice.