Powerful Tube Amp for SF Strads?


I am looking for recommendations for a powerful tube amp for my Strads. A powerful tube amp which truly excels at palpability, musicality but also has very good bass control (though bass control is not as 'mission critical' to me as palpability).

My current amp (see below) sounds great to my ears!...but runs out of steam much too soon.

My system today:

Zanden 5000S DAC
CJ Act 2
CJ MV60 (EL 34 tube)
SF Strads (4ohms, 92db sensitivity though impedence does dip to 2.5ohms)
Velodyne DD-18 (run in parallel)
Transparent Ref/Ref XL cabling throughout
Purist Audio Dominus PC

In addition to recommendations, any thoughts are welcome on Wavac, Audio Note, Zanden, VTL, CJ LP275...or monoblocking MV60 (EL34)? Thanks!

Lloydelee21
lloydelee21
Watch me!...hehehe...Trust me, when I pushed past 71 on the preamp and got my neighbor upstairs, I was trying to see if I could make it feel like a club in my apartment. It worked!...but a little extreme! There's loud and then there's deafening just to see if the system will crank. Guess it does...;) BTW, Jeff, that's a nice system you've got there...enjoy!
The SF Stradivari is for sure one of those speakers to hang on to for life. every speaker shall do less to an extent with many common amps, will work good with certain amps, and will perform superb with only couple of amps.. no matter what powerfigures or topology or brand alone.
even amongst the very best SS amps there will be one which will get the nod above the others with a typical speaker.. in any case i found the speaker & amp combination to be a very crucial one, and if you got it right you made a quantum leap.
if i read point 1 to 7 it is very likely you got a stunning combination found!
take your time to squeeze out the last say 10% in refinement and get into that magic zone.
i'm curious about the greenbias position and the full class A bias and how these two settings behave soundwise.

my tip: check out the LessLoss and Stealth powercables.
Hi Tuboo,

I have now spent 12+ hours listenin carefully. Answers to questions I have been asked:

1. Biasing. I tried low volume at 50%...on pre-amp that goes to 99 and where 71 will deliver volume to punch thru 2 floors of concrete cynderblock to disturb my neighbor, once I past 19, I found 75% was necessary to feel like I had full class A.

Once I got to 30...the level most audiophiles would 'start' their true auditioning, you really want 100%. The technical differences are almost non-existent in the sound...but 100% really does have a sense of naturalness that you 'feel/sense' rather than articulate just by hearing differences in decay or added detail, etc. But you definitely feel it intuitively.
The nice thing is that you can almost gauge how much class A you are using by the heat dissipation. When the amp starts to steam, the volume is low and the amp is burning off 'excess Class' via heat. But when volume is cranked up enuf, the unit starts steaming less and becomes like any tube amp. For me, I find 38 on my pre-amp is where I find the unit heat very normal and therefore enuf class is cranking music as opposed to dissapating heat.
2. I was shocked to find that the Strads were not getting nearly as much help now from the Velodyne DD-18 as I thought. Wow...the 2 10" cones on each speaker are really pumping now, and if I mute the Velodyne, it shocking how little I miss it. Maybe 5% extra for most House tracks! On the other hand, because I am a bass freak, I find that on certain tracks, that extra bass really adds a quality, visceral touch that is indescribably satisfying. Plus, on movies, it's killer.
That's all for now. Hope that helps. Thanks!!
Tuboo,

To try to give you a (slightly) more 'objective' sense of the biasing options, I would say that once the volume requirement surpasses the ability to stay in Class A, it sounds like very high quality solid state. There is a slight hardening of the treble...and because this is an extremely wide bandwidth amp, you really feel the treble harden when the volume breaches class A in the lower 2 biases. That said, it is still very good SS...much purer to my ear than a top level krell...but for a tube lover (who is expecting absolute purity of tone and a natural sound), I do feel this difference. As I said above, the technicals (decay, accuracy, space) will be nearly indistinguishable between biases...but I definitely "feel" the difference. Because I play at 38-50 on all music, I leave it on at full bias. According to Gryphon, the amp draws 800 watts from the wall...a lot but not horrible in the context of a home. Hope between the posts above and this one that you get some idea of the differences in biases.
Hi Lloyd

IMO, just leave the Gryphon in full class A.
Sounds better that way and living in the UK, you always need a heater :-)

cheers