Fi style Foreplay III

[Thermioniclife]

Hi Mr. Joppa,
I thought I had expressed that by stating that the amp probably draws about 1/2 of the rating of the fuse perhaps even less.
I believe the question the member asked was what was the consumption of the amp during normal operation not at initial start up.
Btw I am currently in the process of designing /building a Foreplay III circuit using 7193 / 2c22, 0D3 and a Pt 10 trans.
I had a fp3 years ago that got nabbed from me and feel sentimental about that piece. Any personal thoughts regarding the 7193?

 

[Paul Joppa]

I don't recall ever seeing or hearing about the 7193 - cool find. There's not much information, but it seems to be a 6j5 with (slightly) higher dissipation  rating and a really odd envelope. So it should work pretty well, the 6J5 and 6SN7 are very linear. You'll need four, which will make a pretty dramatic visual presentation! Should be a nice preamp - I'm still using my FP-III at home, with Eros and Paramounts. You may want to use shielded cable for the grid caps, especially the voltage amp, so they don't pick up RF interference. Post pictures when you get it going? I'd love to see it.

There's a 7-pin miniature version of the 6J5 as well - 12H4 - with 6/12v heater; I only ran across it a few days ago.

 

[Thermioniclife]

Thanks Paul,
they seem quite similar to 12au7's and 6sn7's. I agree that there is not much info about them but I have read some articles that suggest that they should sound nice. I read about  using shielded cable for the grid connection and will do so also. I love the look of the tube also. I have all the parts and 4 Ken-Rad 7193's, I'm in the process of designing a chassis using Front panel express. I may try to design a chassis similar to a Fi audio style preamp or power amp. will definitely post when the build gets underway. check out the attached photos of a couple of Fi audio designs, I think they are pretty cool but not the easiest to build. I may also go with a more traditional chassis if I can't wrap my head (and my budget) around it.
Be well.

 

[Tom-s]

Nice to hear about the monAmours 6stringblues!

Thermioniclife, could you make a topic / forum blog about your FP3 build? I'd love to see it come to life!

I agree that there is not much info about them but I have read some articles that suggest that they should sound nice. I read about  using shielded cable for the grid connection and will do so also. I love the look of the tube also.
Be well.

In my Crack i've used CV6 / 7193's extensively and it's a very very nice tube. I can imagine it's a good step up from the 12AU7 in the FP3 circuit (in Crack it is). I've never had any trouble with the grid wire's being non insulated in my Crack adapter (12au7 -> dual 7193 or CV6). I can imagine the FP3 being more critical about hum.

 

[Thermioniclife]

Hey Tom-s
I will try to start a topic on the build. I don't know if I have enough discipline to keep up with it.
I have some nice single conductor shielded wire around here somewhere.
Glad to hear the tubes worked out in your Crack.

 

[Paul Birkeland]

The draw of the MonAmours should be 50-ish watts.

 

[6stringblues]

Thanks Paul, that is what I was looking for.

 

[Doc B]

Regarding the Fi amps, Don was an amazingly creative artist and a friend. I'd recommend copying the look, but you might want to spend some time thinking about the wiring layout. Back when we were all just getting into this SE stuff I recall Don sending a preamp to Buddha to sort out some fairly gnarly noise issues that were subdued with some reworking of the grounding and wire dress. IIRC the issue was at least partly due to the many separate panels and how they were connected.

 

[Thermioniclife]

Roger that Doc,
While I like his design aesthetics I realize that the build will be brutal, therefore I will build a more conventional chassis.
As I stated before I have all the parts (ha ha we will see) for the build and a Pt-10 and shoulder washers  compliments of Queen for the job. Thnx Queen luv ya.
Be and stay well to all at Bottlehead and the community.
will post when underway.
Regards,
Lee

 

[Thermioniclife]

Doc,
I might still consider the chassis design to reflect Mr. Garber's designs. this a problem I have that is called paralysis by analysis.
It's quite disturbing, we shall see. I have a Mainline on order in the meanwhile to keep me occupied as I wrap my head around the build . I am pleased that you knew him and appreciated his products. He lived on long Island N.Y. and I am a native of the North fork in the town of Southold.