Allnic OTL/OCL Phono vs Allnic DHT

$48K is a bargain compared to the SS  Vitus MP-P201@64K

AND you get the tube magic that SS SOTA cant replicate.  

https://jaguaraudio.com/product/mp-p201-mk-iii-phono-preamplifier-by-vitus-audio/

Might as well drop another couple grand for vintage Euro glass for the Allnic too, just cuz.

Ralph, As phono stages go, OCL is more unusual than OTL, of course. I thought that was salient to my point. As the owner of an MP1, I know about the OCL/OTL linestage section, but the built in phono is capacitor coupled to the linestage, at least in my unit.

Here are some additional resources that may be useful-

From the Allnic H-10,000 OTL/OCL manual:

“Some circuit experts might be concerned about DC potential in the music signal in an OTL/OCL design.  However, the chance of this problem occurring can be essentially and reliably 100% mitigated. To do this, Allnic uses a “floating power supply circuit”, a design that deals with the issue by not creating any DC potential in the first place, or such a small potential that it is harmless.”

My personal experience with these units:  the H-10,000 requires less user attention for tube maintenance, more stable circuit and more robust to different environments.  

For the more advanced Allnic circuits I recommend this read:

https://www.kevalinaudio.com/circuit-balance-review-recommendations

For Manuals:

https://www.kevalinaudio.com/copy-of-current-legacy-allnic-manuals

For Reviews:

https://www.kevalinaudio.com/allnicreviewcurrentlist

“Some circuit experts might be concerned about DC potential in the music signal in an OTL/OCL design.  However, the chance of this problem occurring can be essentially and reliably 100% mitigated. To do this, Allnic uses a “floating power supply circuit”, a design that deals with the issue by not creating any DC potential in the first place, or such a small potential that it is harmless.”

That's an interesting turn of phrase ("floating power supply circuit").  Usually you would design the unit so as to have as little DC offset as practicable at the output, then cancel (or greatly reduce) that small DC offset with a servo circuit. Perhaps Atma-sphere can comment on whether the Allnic circuit might be unique. I think Allnic may be saying they treat the power supply as in a circlotron, a la the Atma-sphere products. Semantics.

To do this, Allnic uses a “floating power supply circuit”, a design that deals with the issue by not creating any DC potential in the first place, or such a small potential that it is harmless.”

@kevalinaudio We have two patents concerning a method of using a Circlotron circuit for this purpose as @lewm  suggested. It indeed is

a “floating power supply circuit”, a design that deals with the issue by not creating any DC potential in the first place, or such a small potential that it is harmless.”

During warmup, the Circlotron circuit can produce small DC offsets less than 1 Volt. Once warmed up the DC Offset is typically less than a milliVolt. Its plug and play since no adjustment is required. 

However its pretty obvious such a circuit is not used here. 

On reading the documents at the links you provided, it appears an SEPP circuit is used. The SEPP is a push-pull circuit of the 'totem pole' variety not unlike what you see in Futterman OTLs. They are often used in headphone power amps.