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Active FETs vs. Step-up phono stage designs

I've noticed quite a few threads on A-gon discussing step-up transformers recently, and it got me thinking of the different applications in the phono stage design. I'm curious of the advantages and disadvantages of designs that employ step-up transformers vs. active designs with FETs, especially in tube preamps. Examples would be the new Manley Chinook vs. the Rogue Audio Ares with its custom Cinemag transformers, or the highly-regarded Andros, which also went the step-up route. I'm thinking of upgrading my solid stage phono preamp in the near future, and would like to hear your opinions (and I know we have a few designers posting regularly) regarding this subject.

actusreus
lewm
13,325 posts
 
Thanks for that URL, Dave. I did not know about MAT12. I wonder if it is equally suitable to our application, compared to the MAT02.
dgarretson
2,605 posts
 
Lew, another hobbiest has used MAT12 interchangeably with MAT02 in this application, so I don't think there is any issue.
dhl93449
455 posts
 
Have you noticed the pricing on this part? $15 in thousands quantity? No wonder folks are being driven to op amps.
lewm
13,325 posts
 
I guess I would be reluctant to buy $15,000 worth, in hopes of selling the extra ones to "friends". Even for a manufacturer, that would be a lot of investment for one part. But generally if you search diligently you can usually find a vendor who is willing to sell parts in low volume.
lewm
13,325 posts
 
Interesting addendum. I received an issue of TAS yesterday that contains a roundtable discussion of amplifier and preamplifier design by a collection of well known designers, e.g., Rowland, Pass, Curl, Carver, Lamm, etc. It's mostly self-serving drivel, a la TAS, but at least one or more of the panel notes that "audio grade" solid state devices, meaning devices specifically made with a view to no compromise audio component design and build, are becoming ever more scarce. He fears that his work will eventually be hampered by sheer lack of the optimal parts. Other panelists were more optimistic, however.
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