Should I get the Art Audio Jota


I'm seeking advise on what I would think should be an upgrade. Would the move from a cj Premier 11a to an Art Audio Jota (high current model) be recommendable within my system.

Modwright 9100ES W/ Platinum Truth cdp
cj 17LS Pre
JM Lab Mini Utopias
Siltech G3 interconnect and speaker cable
phaelon
That warm, slightly fuzzy sound has always been C.J.'s trademark. Was there in my first C.J. product from 1984 but I liked it then. First time music sounded inviting and warm. My girlfriend liked it, too. The last product I had was a 16LSII pre-amp which still had a similar sound. The Joule Electra LA150 that replaced it is much more open and naturally dynamic, to my ears.
Phaelon -
"Since I acquired the Modwright, there seems to be just a little too much of a fuzzy warm aura that I'm attributing to the Premier 11a."

Tomryan -
"By the way, the CJ 17 and 11 are both a bit "fuzzy" sounding, kind of like looking outside through a window screen."

Ultimately, it's your ears and wallet who have to be final judge. But, good tube equipment has evolved a long way since the heyday of the 17LS and Premier 11a. Resolution/refinement/transparency being a few of the biggest areas. (musicality is open for debate)

Since you like the overall sound, except the fuzziness, have you considered comparing the 17LS & 11A to CJ's newer offerings? I'm sure they have come a long way.

Hi Darkmoebius,
Right or wrong, I've always thought that the synergy between high end components was atleast as important as their respective quality. For the time being, I want to hold on to the 17LS and the Minis so I'm going to be more opened minded about a replacement amp, which I consider my single biggest opportunity. I'll welcome posts to the contrary.
Phaelon - "I thought most of the posts would concern pairing a single ended amp with the Minis."

Yeah, that's one of the reasons why so few people achieve satisfaction out of attempts with SET. It's not just about the amp/speaker combination.

In my experience, SET setups are far more sensitive/revealing of total system synergy, than push-pull. It's not a simple plug-n-play experiment like using high-powered amps. Your really have to be willing to go over your entire system with a fine-toothed comb to get the glory.

That, doesn't have to mean spending tons of money, just getting the proper match of pieces. Input and output impedances are far more critical, load curves for speakers, capacitance of cables, etc.

And, upstream components are often ruthlessly revealed. Which is actually better than the flipside of that coin where upstream units prevent the full potential of the SET amp from being heard.

Anyway, back to your initial question, the high-current Jota should do pretty well with the Minis. Though, you may never know exactly how well until you try a different preamp.

The one good thing is used Art Audio amps hold their value extremely well. You can check it out for a few months and if the match is not your liking, then you can resell it for close to, if not exactly, what you paid for it.
Darkmoebius,
Thanks for the clarification; your point is well stated.

This was unexpected - I thought most of the posts would concern pairing a single ended amp with the Minis.
Phaelon - "I wasn't aware that there were preamp designs specific to single ended amps. "

Hi, I didn't mean to imply there were actual topologies specific to preamps used with SET amps. Just that there are sonic unique sonic traits in the best SET amps - their own form of transparency, tonality, etc. that is not readily apparent or existent in push-pull amps. So, if a designer/manufacturer is only fine tuning their preamps via PP amps, they would never notice these traits missing or degraded.

I'm not saying SET is inherently better than PP, each has it's benefits, just that is distinctly different in it's sonic presentation. Preamp designers who also build SET amps or work with them make sure these traits are preserved.
"By the way, the CJ 17 and 11 are both a bit "fuzzy" sounding, kind of like looking outside through a window screen. The AA would be more like the window without the screen."

Hi Tomryan,
That was pretty much my thinking, and while I've only listened to these two seriously as a set, I'm presuming that the 11a is by far the fuzzier of the two. I'm also hoping that with the right tube upgrade, I'll be able to find a synergy between the 17LS and the AA. My plan is to buy an amp on the used market so I probably won't have the opportunity for audition. I definitely wouldn't want the cj to exert such an influence over the AA that I would never hear it's special attributes; in fact, I was hoing for the opposite.
Some recordings have inverted phase but it usually sounds, to me at least, as if only one or two mics were the culprits. The sound becomes "phasey" and puts pressure on my ears. Some of Hendrix's stuff was intentionally recorded out of phase, but I have jazz and pop recordings that are obviously just mistakenly so. On a good system (like most of us have) the phasey-ness becomes obvious.

I've heard recordings where the piano and sax sound great but the drums and upright bass are out of phase - they pressurize the room in uncomfortable ways and seem to be smeared all over the soundstage.

By the way, the CJ 17 and 11 are both a bit "fuzzy" sounding, kind of like looking outside through a window screen. The AA would be more like the window without the screen.

If your room is small to medium sized, the high current AA should work great, depending on the kind of music and at what levels you listen.
A phase that is being inverted by a component doesn't require correction elsewhere because up to 50% of all recording have been recorded with inverted absolute phase (unintentionally).

Chris
OK, maybe I'm thinking wrong. I've been considering the 17LS a strength in my system and my intention was to maximize it's virtues with an amplifier upgrade. I wasn't aware that there were preamp designs specific to single ended amps.
Hi Phaelon,

I agree with Misskuma, the CJ will probably assert it's own approach to sound over the Art Audio Jota. I've tried several preamps ahead of my AA PX-25 and the sonic influences are readily apparent. I ended up going with a passive transformer volume control to retain the transparency and tonal purity.(not suggesting you should do the same)

But, there's no way to know until you try. Test it out, but I would highly suggest using a preamp intended to be used in a SET system. Or, at least one that was designed with SET in mind as an option. There are certain unique aspects or traits (and highly desirable ones) that just are not existent in many PP amps. It is important that they are preserved.

There are plenty of choices significantly different from CJ. Consider an Art Audio, Shindo, Air Tight, etc.

Of course, any well-designed, well-executed, linestage should perform well in any system and let through everything preceding it. I think most of us will agree that there are many that fall short of this.
Phaelon, I have read from the review in 'Enjoy the music' that the CJ 17 LS inverts the phase. You need to take that into consideration and reverse the speaker terminal connections.
The Jota has an input sensitivity at 400 mV (0.4V). This would mean that probably you can run the Jota without a line stage by either:
- use a passive volume control stepped attenuator and selector like Goldpoint or other passive pre-amp or
- order the Jota with that same type attenuator (if your intention is to order it).
Then you may just not need the CJ.
Thank you for your posts everyone. Does anyone else feel like Misskuma - that the cj/AA pairing doesn't work?
Jbello is simply incorrect.

The Jota will drive the Mini Utopias effortlessly. I've driven far more difficult loads to paint peeling levels with it.

Disclaimer: Art Audio retailer.
I think the amp speaker match will work well. I own a pair of Micro-Utopia's that I can drive to deafening levels with 24 tube watts. Though not exactly the same as the Mini, I'm guessing the electrical specs, sensitivity and impedance, are nearly the same. And the Jota should be a significant upgrade over the 11A. I used to own the 11A and I've owned many amps since that better it, as the Jota will as well. Good luck and happy listening!
A sideways move at best. Not enough power for this speaker. Most small speakers need more jump to come alive. They will play but you will lose most of your dynamic range. If you are also going to change speakers that might be a different matter.
From what I know from some reviewers about SETs and I have read a lot the Mini Utopias will be successfully driven by the 24 watt Jota (high current version).
Some SETs have even been reviewed driving the Mezzo Utopia which is a heavier load.
24 watts of SET power is not the same as any other 24watts.
In the SET category a difference of 5 watts is a lot.
Some reviewers have driven the Wilson Watt/Puppy 7 (nonimal impedance 4 ohms) with a 23 watt SET to a satisfying results.
It is true that the Watt/Puppy is more sensitive than the Mini Utopia but still they are a heavier load having in mind their impedance variations.
The Mini Utopias are relatively small speakers having a nominal impedance at 8 ohms (Correct?) and I think that the Jota will drive them to satisfying levels.
At least for me ...
Your pre-amp should do in my view.
I also recommend try to listen with your preamp. ( I own hi-current Jota monos )

I never cared for the CJ pre/AA pairing, but that's me.
A preamp influences the sound of the amp a lot.

You'll be definitely breaking the same make synergy of of the CJ kit in that you might have to look for a preamp that will work optimally with the Jota.
Thank you. I've been told that my speakers are more demanding of an amplifiers current than it's wattage and that the Jota BX would actually sound more powerful. Since I acquired the Modwright, there seems to be just a little too much of a fuzzy warm aura that I'm attributing to the Premier 11a. I'm seeking something a little more truthful.
Depends on what your musical tastes, sonic priorities, room size, and average listening volume is.

There is a BIG difference between a 70wpc PP 6550 amp and a ~24 wpc SET amp. Not trying to imply that one is better than the other, just that there is a big difference in how music is presented - especially in the midrange and bass.

I really suggest that you audition the AA Jota or any other high-powered SET amp in your system before buying. It will take a week or so of serious listening to really appreciate most of the benefits (and drawbacks) of PP vs. SET.

BTW, I own an Art Audio PX-25 and love it.