Review: Conrad Johnson CT5 Tube preamp


Category: Preamps

I wrote a review of the CT6 preamp from Conrad Johnson last November. It has been a source of great musical pleasure and will continue to serve as such in my audio system. I suggest you read that review as well.

In a followup post, I described a very brief comparison that I did to the costlier CT5. I have since had the opportunity to do a more lengthy comparison,
which led me to write this review.

As vast as the soundstage of the smaller CT6 is, the CT5 is even wider and deeper. It has a presentation I would term wide open. There is a rooted-to-the-earth quality. This quality is at least partly due to the
incredible control the CT5 exhibits, particularly in the lower reachs, where it seems to descend to the center of the earth. It is also due to the seemingly limitless dynamics and punch the CT5 tosses around with the greatest of ease. This quality reminds one of a high-power amp that takes charge of the speakers.
There may be other preamps that can do this, but this is the first preamp in my experience that has this charactertistic.

What places this preamp in a truly rarified league is how it is able to do this, and at the same time, is capable of great delicacy and highly-refined finesse.
The high end exhibits the finest filigree of detail in a sweet and delicate manner. Yet it has no problem raising the roof and sounding like a power house.
I have not heard any preamp capable of doing this, not even a $15,000 unit I recently listened to. To be fair to that unit, I did not do a direct comparison, however.

I believe the 6H30 tube, at least in this implementation, is partly responsible for some of this. The 6H30 can sound sterile in some designs, and it has different sonic characteristics than, say the 6922/6DJ8. There are many staunch supporters of the 6922, which is interesting, because it was such a criticized tube in past years. The 6922 does not have the guts, the balls, the legs, the dynamics of the 6H30. It is a thinner sounding, lighter weight sounding, less dynamic tube, that tends to have a sonic spectrum with more emphasis on upper mids and highs, and a weaker bass. The 6922 family has a more upfront
presentation that some people equate with a more tube like sound. This is interesting, because this family of tubes was often criticized for being too harsh, too thin, too opaque, too grainy by many who defended the 12AX7 and other designed-for-audio tubes as more musical sounding than the non-audio intended
6922/6DJ8.

I believe the more bright and forward balance of the 6922 gives the impression of more air and sparkle in the high end, and can fool some listeners on that
basis alone.

DETAIL. The CT5 unravels each musical thread to a degree and level I have never heard before. I was able to hear much more deeply into the mix, revealing
instrumental timbres and details other preamps, including the CT6, were incapable of delineating.

Guitars sounded more like guitars, with the pluck, vibration, guitar body, and overtones all integrated into one coherent, continuous flow.

Vocals sounded more natural, yet more detailed. More at ease; less hi-fi. Diana Krall's voice sounded so right and real on the CT5, that I had to switch between all preamps several times to substantiate to myself that the other preamps just couldn't do the same thing. They couldn't. I listened in awe at how Ms. Krall's lip and mouth sounds flowed with the resonance of her vocal cords and cavity resonances in perfect synchronization.

Cymbals, high hats and brushes had a coherency that was in another league from the CT6. Every element of their complex percussive character was clearly
delineated, and presented in a natural and holistic totality. The individual characteristics and unique sounds of percussion instruments were fully unraveled, yet presented as a totality, not as a disconnected and imperfect collection of sonic elements.

My listening tastes cover a wide range from classical to jazz to vocals. In each genre, I heard the same positive characteristics, whether it be a violin, a voice, a trumpet, or a sting bass.

As real as piano sounds on the CT6, it sounds even more real on the CT5. One can clearly hear the pianist move from the bottom of the piano to the highest keys,
and there is no disconnect, only a coherency and totality of the instrument.

In Big Band jazz, massed brass passages don't sound like a homogenized mass of instruments. I was able to hear clearly each instrument's own place and space
within the total ensemble. And clearly hear the ndividual characteristics of that instrument separated from those of the other instruments in the ensemble.
This is one of the hardest feats for a piece of electronics to achieve.

This is consistent with Conrad Johnson's perpetual striving in their designs to recreate 3-D images that sound more like the real thing. Where you can hear the
air and space around each instrument, not just in a flat, frontal arc, but around the sides and to the back of the instrument. Overtones flew out freely into space in a coherent manner that was true to the character of that
instrument. The brain didn't need to 'rearrange' things to make it decipherable. The coherency was already there.

As with the CT6, the very different sound of the Premier 11 and the Levinson 432 amps did not prevent the CT5 from improving upon the end result with both combinations. The traditional tube signature of the Premier 11 bloomed to its finest, providing palpable, full images that were rich, but not overweight. Again, the Levinson 432 exhibited its finely-detailed and delicate treble at a new level of refinement; its slightly cool, yet beguiling and natural midrange more immediate and appealing than usual; its immense soundstaging abilities expanded even further, and its powerful bass more dynamic and impactful than I thought this amp capable of.

By comparison, the Audio Research LS25 sounded sterile, anemic, and disjointed. The soundstage was much smaller, and instruments were not separated well. There was a thin shrillness to the upper frequencies. The midrange lacked body and
cohesiveness. There was grain in the mids and highs. There was a certain coarseness that made itself present quite often.

The Macintosh C2200 was more pleasant sounding than the LS25, but had a loose bass. It pushed the midrange forward, which I found to be a noticeable
coloration. The midrange was not nearly as detailed or resolved as the CT5, and it had an added texture that some might find pleasant. The highs were less
shrill than the LS25, but still quite unrefined compared to the CT5. Soundstaging was better than the LS25, but there was no comparison to the finely-resolved and detailed CT5 imaging ability.

Physically, the CT5 preamp is robust and striking. A 32 pound beast that combines retro with modern. The subdued gold, curved portion of the front panel
is highly attractive and picks up a subtle glow from the 6H30 tubes mounted within its cradle.

Operationally, I found the heavy metal remote to work perfectly, as did the preamp. The relay clicks that occur with volume changes are not objectionable to
me at all, and I am used to them with the CT6. These are sealed, gas-filled, gold-plated, silver contacts that should last forever.

Internally, the immense size and shear number of polystyrene, polypropylene, and, yes, the famed expensive Teflon capacitors are awe-inspiring. These caps are absolutely huge. I have seen the internals of many preamps in this price range and above, and none of them have this quality and quantity of capacitors.
CJ is at the top of the heap in this regard. It appears no one wants to spend the money to do it this way. It is actually shocking to see the cheap red Wima caps in BAT preamps; the mediocre REL caps in ARC and Aesthetix; worse yet, the cheap electrolytics that so many far-from-cheap preamps use in abundance.

In Wes Philips' Stereophile review of the CT5, he found minimal difference between the $13,000 ACT2 and the CT5, even finding the CT5 superior in some areas. This prompted CJ to revise the ACT2 to the Series II. They could not sit on their laurels with this type of performance from the CT5.

In the CT5, Conrad Johnson was able to greatly expand upon its signature sound of musicality, naturalness, body, and, most importantly, capturing the heart and
soul of the music. At the same time, CJ achieved notable refinements in accuracy, detail, soundstaging, authority, power and bass quality. Few tube preamps will provide bass at this rarified level.

Hearing a product that sounds this good leaves you in awe of how far our quest in recreating the absolute sound has come. This leaves me to reflect on how much I am willing to spend to get to that goal. Certainly the CT5 is near the top of the heap in that passionate pursuit to achieve the highest fidelity that is possible, and is at, or near, the state of the art.

Associated gear
B&W 802 Nautilus
Conrad Johnson Premier 11 amp
Mark Levinson 432 amp
Northstar transport and DAC
B&W N802
Various cables

Similar products
Conrad Johnson CT6
Audio Research LS25
MacIntosh C2200
zear
Great review. I would like to add the preamps used in your comparisons are not of the same price range. The CT5 is $3000 (67%) more than a C2200. This is not negligible! The CT5 is $2000 more than the LS25 when it last retailed so in this case, it sounds like the C2200 is the best bang for the buck. That is a parameter I try to keep in mind because, afterall, cost does make a difference.

What would be even more interesting (and fair) comparisons would be to the McIntosh C200, ARC LS26 and BAT VK51.

One thing I have disliked with CJ gear in the past (owned and auditioned) is that the sound is a little dry for my tastes. But from the recent reviews, it sounds like CJ changed that with the lastest crop. I'll have to give them another try down the road. Thanks for your review!

Arthur
I am currently an owner of the CT5 and I am auditioning the VK51SE in my system. I have BAT 150SE amps and I was using adapters. I am thinking of going to a balanced system. My Ayre unit sounds much better balance than Se. I have to agree with the above review, the CT5 is really is a special piece of gear. The best way for me to explain the difference between the BAT and cj is the CT5 gave me the huge wall of sound but I didn't see into the sound stage as well and the images were not as sharp as I am getting with the BAT preamp. I do feel the tonality and the midrange of the cj is very well done. It is fast and dynamic and good for all music. I am actually waiting for the VK52SE to become available after hearing the REX.
Aball,

Sorry, but I don't have access to preamps other than those I used. That said, the house sound of Mac and ARC was discernable from these still expensive units. I would certainly have chosen my CT6 over these two units in a heartbeat, yet alone the superior CT5. From your system, it is obvious that you are a Mac fan. I don't think the C2200 is a 'bargain' as you state. It was pleasant to listen to, but had colorations that got in the way of the music, particularly the forwardness it has in a certain frequency band somewhere in the midrange. This was pervasive in any recording. For a piece that retails for $5100, I don't consider this a bargain.