Any thoughts on Phaedrus VF14 tube?

[distorter]

Has anyone ever used a Phardrus VF14M Gold Dot tube? Looks like a possible replacement tube for my U47?
How’s the sound?

http://www.phaedrus-audio.com/VF14_gold.htm

 

[warpie]

How much do they cost? Can't find the price on their website.

 

[distorter]

How much do they cost? Can't find the price on their website.

http://www.phaedrus-audio.com/shop.htm

 

[Michael Tibes]

Just out of curiosity, how much is an original used VF14 nowadays? The Phaedrus seems relatively cheap.

Michael

 

[Lee_M]

Going by the video, it seems to be a solid state (IC-based) tube replacement circuit, built into a VF14-style case. You can see part of a schematic (which I assume is for the Phaedrus VF14M) at around 1:08.

 

[distorter]

Just out of curiosity, how much is an original used VF14 nowadays? The Phaedrus seems relatively cheap.

Michael

They sold for $2000-$3000 now. Ridiculous.
A $1000 Phaedrus VF14 is even more ridiculous.

 

[distorter]

Going by the video, it seems to be a solid state (IC-based) tube replacement circuit, built into a VF14-style case. You can see part of a schematic (which I assume is for the Phaedrus VF14M) at around 1:08.

That’s bad. A solid state “tube” sold for $1000?

 

[gyraf]

Discussed over here too - VF14 Rejuvenation in U.K.?

..look toward the end of the thread for comment on that company's future..

 

[Gus]

A company can charge what every they want. That should inspire a DIYer to design and built their own.

I have built a number of solid state circuits that have a PART of the tube microphone sound. I tried more complicated circuits at the start and ended up with simple circuits. There are number of different circuits to achieve close to the same results.
Transistor based ones and IC based ones, external powered and phantom powered
built 6 circuits so far have a few more designed waiting to be built.
The next build will most likely be based off the 49 circuits at around 120VDC.

I also have add on circuits that should allow the use of more modern tubes helping with noise issues

 

[Lee_M]

That’s bad. A solid state “tube” sold for $1000?

Yeah, it seems incredibly expensive for what it is. The regular and "red dot" versions aren't so horrifically expensive, but are still a lot more than I'd be willing to spend on even a vintage tube, let alone a solid state "electronic tube".

 

[distorter]

Discussed over here too - VF14 Rejuvenation in U.K.?

..look toward the end of the thread for comment on that company's future..

Lol right on! Thank you for sharing this useful information!

 

[GeorgeToledo]

I had thought these devices were based on the old idea of the fetron, just with stuff like the Phaedrus being reworked directly for the VF14 (or AC701/5703) market. Here’s one somewhat relevant fetron:

https://www.radiomuseum.org/tubes/tube_tr1018.html
The fetron linked above was marketed as replacement for 408A, for example.

I think you can find tear down articles about the fetrons, and maybe data about making them.

 

[capacitorless]

Interesting stuff! JFETs cascoded, pentode-ish?

https://el34world.com/Forum/index.php?topic=12710.0

 

[TLRT]

They sold for $2000-$3000 now. Ridiculous.
A $1000 Phaedrus VF14 is even more ridiculous.

3000EUR+ for mic grade tested tubes, I have some

 

[TLRT]

Discussed over here too - VF14 Rejuvenation in U.K.?

..look toward the end of the thread for comment on that company's future..

The company won't stop, they will continue,I speak with them quite often.

 

[TLRT]

Btw, Grosser(RIP) made a good replacement based on a real tube, but it has some flaws. However sounds good, I'm just organizing a test with real VF14's, Phaedrus, Grosser etc to listen what are the differences.

 

[rock soderstrom]

I'm just organizing a test with real VF14's, Phaedrus, Grosser etc to listen what are the differences.

Good idea, good entertainment! Keep us posted.

 

[laurentj]

Really enjoying the Phaedrus with 3U M7 capsule, have no real U47 to compare with but most times prefer it over a good U87.

 

[RuudNL]

FWIW: I once replaced a defective AC701 with a Phaedrus 701 in a M50 microphone, and the client is still very happy with the microphone.
(And it's true: there can't be very much inside this very small tube. Probably SMD components.)

 

[k brown]

I always assumed a simple FET circuit would be more tube-like than anything using an op-amp. By all accounts the FET circuit that Decca used to replace the tubes in their M50s was a very simple one.
https://groupdiy.com/threads/schematic-decca-m50-fet.69776/