2. amps-preamps
  3. 1199661843

Rich; organic true balanced amp w good detail $6k

Suggestions welcomed & appreciated- here are the Criteria:

- fully balanced architecture
- rich, organic sound, extended bass, silky highs, but not at the expense of obscuring detail
- No OTL (too many tubes/heat)
- SS (Class A bias) or tubes OK
- 20-200 wpc ok, the lower the better though all things being equal- well built power supply crucial
- stereo amp easier to put on my Sistrum rack, but mono-bock architecture also considered if better performance
- $6k or less used would be ideal, but would consider up to $8k used if there are no world-beating contenders at the $5k-$6k used price point

Preamp is a modded Sonic Frontiers Line 3- extremely neutral, hence the desire for a richer-sounding amp to balance. High efficiency speakers from Coincident- large open concept room (main floor of house). Re: tubes, have used ARC VT-100 MKIII- good- airy w big soundstage, but meatier mids would be better. Also had Wyetech Topaz 20-watt SET, superb, if slightly lean in the mids (and not fully balanced, but shows you how powerful 20 watts can sound with a well-built power supply) For SS, am considering Pass XA.5 series (they now can run balanced from what I understand?); Clayton Audio M-200 (but unfortunately over the price-range).

Thanks in advance for any suggestions- I have an open mind, so bring it on!
sutts
t_bone
1,182 posts
 
The amp is the end of the chain when it comes to differentially balanced or not, and if there is anything to the "SET" nature of your amps, it will not matter a great deal I expect. I am not a circuit specialist, but given the way that the circuit runs through the tube, I cannot imagine how the "fully balanced" will matter to a true SET - I imagine it will only matter if it is triode-ified push-pull, and even then, circuit implementation will matter far more than whether the amplifier circuit is fully differentially balanced or not (the next part of the chain is speakers, which will not care whether the amp was differentially balanced or not).

The VTL 450s (the old ones, at least) have a triode/tetrode switch on the back (do NOT switch while the amp is on - some speakers do not like it).
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dgarretson
2,599 posts
 
I went from an ARC VT130 to a BAT VK75SE. I later modded the BAT with V-Caps and a few other minor changes that significantly improved resolution, neutrality, dynamics, bass extension & control-- IMO putting the amp at par with a top OTL. There is no area of this modded amp that is not way over the top of the ARC VT series. The 75SE can be converted to a monoblock if desired. The amp has been in production for quite awhile, but with a lite rework it's pretty astonishing. And used examples are available below $5K.

I share Tvad's positive opinion of the Spletz autoformers. In my second system they do a nice job of marrying a 3wpc SET to Wilson Watt/Puppy-- a very difficult load. In the some configurations they can make a mid-powered tube amp sound like big monoblocks.
billyg1
81 posts
 
clayton m200s or m300's
atmasphere's avatar
atmasphere
11,841 posts
 
Sutts, FWIW there are amplifiers out there that run as hot as OTLs. In fact, OTLs only run hot if they are class A, not due to the number of tubes. It has to do with the energy that is dissipated in the output section, not the number of tubes.

For example, the BAT VK-60 and VK-75 run *hotter* than equivalent-powered OTLs. The same is true of the push-pull Lamm- this having more to do with the power tube used by those companies as well as the class of operation.

Israel is getting an OTL for his own use BTW (one that is also fully balanced-differential). Coincidents have been an excellent speaker with OTLs for years.
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