CJ CAV 50 vs. VTL IT 85 vs. Rogue Tempest

I also owned a CAV 50. My impression of the amp is, it's abit colored, and slow in the timing domain. It is kind of a dark sounding amp. Might marry well with a pair of brighter speakers. After carefull listening, it is not a bad amp for the money, but has a distinctive signature. I would think the JM lab mini utopias would want alittle more power than that to open them up. The VTL stereo 150 might be a good match for those speakers. I can't comment on the Tempest. Hope that is helpfull.

I've been a tube head for about 30 years and I'm a bit of a DIYer. I'm QUITE impressed with my C-J CAV50. I've owned the "who's who" of tube amps (Cary, Jadis, VAC) as well as modified vintage and built from scratch tube amps. I also have several friends that are VERY experienced with DIY, vintage and the "who's who" amps. We were all BLOWN AWAY by the stock CAV50. I have to agree about the dark and sort of sluggish sound...but that can be cured (read on...) The amp comes from the factory "hard wired" for a 4ohm load; this is not optimum for all speakers. I found that re-wiring it for an 8ohm load makes the amp sound MUCH faster and not so dark. I also converted mine to TRIODE...a HUGE improvement in all areas. The amp is MUCH faster, more transparent, more liquid, and significantly more open. YES...just like with the output load this is VERY speaker dependent and will not work for everyone. BTW, both the output loading and the triode conversion are STOCK and RECOMMENDED modifications...I got the info directly from C-J! If you're good with a soldering gun you can do it yourself...you can take it to your local tech...or you can send it back to C-J for these conversions. Now for the not-by-the-book modifications. I replaced the coupling caps with AN copper-foil-in-oil...WOW! A HUGE improvement...it's hard to describe but the sound became more detailed, more transparent, more extended as well as more rich and harmonic. I also tried EVERY tube (vintage and modern) on the market. I found the LONG PLATE tubes for the input and phase splitter to sound best (more plate area...DUH). I ended up using my old favorite RCA "red base" 5692 to replace the 6SN7 in the driver position (I tried ECC32s, Sylvania 6SN7Ws and chrome tops...money was no object). I also replaced the 12AX7s with 12BX7s and the 12AU7 with a 12BH7...they have about TWICE the plate area and give the amp an effortless character that can't be compared (they are also QUITE cheap). I preferred them to the overpriced vintage Telefunken, Brimar and Bugle Boy long plate tubes that I was using. I wouldn't recommend these modifications to the faint at heart...I've blown a filament fuse a couple of times (these tubes require 2X the amperage). I've spoken to the techs at C-J and they assure me that I'm still WELL within the operating limits of the amp (the amp is built like a tank). All of my audiophile friends can not believe their ears when they hear my "humble" C-J integrated...it is a REAL mind blower! I'm planning on doing some more mods to the amp (such as replacing the diodes with high speed HEXFREDs). I've owned DHT SET amps and I've owned PP pentode and Ultra Linear amps...I now KNOW that PP Triode is the way to go for me...it has most of the liquidity and midrange of SET and most of the slam of pentode...I consider PP triode to be the best of both worlds! This may not be my last amp but this amp will ALWAYS have a place in my home.

Typo in my posting...it should read 12BZ7s not 12BX7s...sorry!