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
Hi Lloyd,

Zero's are nothing more than impedance matching transformers(actually autoformers - just a primary instead of the primary & secondary in transformers). They serve exactly the same function as output transformers in tube power amplifiers, which are used to match the impedance of the output stage to the speakers.

Paul Speltz seems like a great guy from his postings and is extremely proud and confidant of his product. It probably wouldn't be difficult to get a trial out of him. He also can wind custom Zeros for specific situations,if I remember correctly. Although, yours is a fairly basic one.

Of course, excess power and headroom are always a good thing with all speakers, especially medium to low efficiency ones. So, in the end, you may need 100-300+ watts to fully realize the potential of your Strads on dynamic passages. Even then, though, the Zeros would help.
the Dominus in itself is a great PC but the next level Anniversary easily betters it. if you crave for speed and resolution i would however not pick Purist cables as first choice.
the SF speakers benefit greatly from Fast-Authorative- Speed and Resolution amps and cables. remember it is all in the match :-) i would first settle in with your Dominus, take your time and eventually try another PC.

the Speltz autoformers are a solution to a problem for sure.
personally i see no reason to go OTL first and put in Speltz Autoformers later because of bad speaker impedance.
why not choose 'good' speakers first?
i don't say the Autoformers don't work or don't sound good.
but to me it's like towing a caravan behind a sportscar and using slick tires still. well something like that.

i think high wattage as per definition is not a sign of a 'good' amplifier. and you don't need 300 watts to drive the 93 dB Stradivari.
you rather need 50 superb watts. the first few watts count most.
high wattage may be a sign of capacity but it says nothing about quality of powersupply nor authority.
big & heavy amps says nothing about authority and control too.
as a great example the little Cello Encore 50 amplifiers look like little sigar boxes and weigh nothing. i would dare to say these are more powerful sounding then many many amplifiers be it 300 or even 1000 watts.
the 'little' FM 111 monoamps would apply very nicely too.
or the 'little' Boulder 800 series. these amps would get any SF speaker on their knees :-)
don't let specs and size or even marketing 'the bigger the better' mislead. it may account for in many cases but not per definition.

now the big Gryphon is big and heavy for intrinsic reasons. it is one of the few true class A amps out there and this means big heatsinks and so acres of heat dissipation alloy. pure Class A rules be it SS or tubes.
once again congratulations on your Gryphon and Stradivari match and looking forward to read your experiences on Gon.
Thanks, Tuboo! I learn every time i read your posts. As for dominus ferox, if you have specific recommendations on other PCs i should consider, please let me know. I am thinking transparent reference, possibly Gryphon's own VIP or Siltech. Your thoughts/recommendations are most welcome!
personally i see no reason to go OTL first and put in Speltz Autoformers later because of bad speaker impedance. why not choose 'good' speakers first?
Agreed, but sometimes a person is already heavily invested in their speakers(emotionally or financially) and the Zeros are a low cost(& effort) way to seem if a particular amp will work to their satisfaction.

In Lloyd's case, his system wasn't designed around removing output transformers(OTL), so the philosophical transgression of adding an autoformer isn't as big a factor.
yes i can imagine the addicton or a love for certain speaker i got the same for my Verity. and the AtmaSphere OTL is known to me to say the least..
it may be worth trying out the Autoformers which will be great for what they do.
i have learnt alot from mixing and matching through the years and made less than happy choices and also found very lucky combinations as per try.
the interesting thing is that combinations which may form a dream team on paper still don't work out in the real world.
maybe that is just the reason there is some many gear for sale again. and nothing wrong with that.

hard to tell which PC may be best for the Gryphon and your situation. it's part of the journey to buy and resell to finally settle on a particular brand and type.
try out the Valhalla PC too.

fwiw: just today my local CD store put out signs at the street with 50% discount on it.
just happened to be at the other side of the street doing a haircut. i walked in and bought 80 CD's for halve price.
reason for closedown of the shop was a downhill on sales due to internet sales and the www downloads.
it felt doublesided, happy to score so much great titles for a 50% discount, but at the same time felt sorry for the shop owner.
as the song goes: 'The times, They are a changing'