Searching for outputs so I have them around....this and Iron Turtle are on my to do list.. For now Iron Pre and regular XA 252 are doing just fine.well, I didn't tried it yet, but certainly on list soon
it could be helluva SUSY amp (in fact, more like Ultrasymmetry, even if Papa denies its existence )
it should work, no doubt
few major things, some already addressed:
Iq stability - flawless, tick
relative DC offset - need to check, servo if needed
deliberate ruining of symmetry, to invoke 2nd dominant ... need to be addressed
all in all, at least few days of serious work time and, necessary Lucida Intervala here and there
power ..... am I over the top, expecting 150W@8R ?
but, as that.... completely new amp, I'm not interesting in simple bridging, that's already doable
certainly yes, and that sort of preamps is - again - exactly suited to have great output swing, being constructed as that
though, majority of those, even with highish gain, are simply going nutz when seeing 2Vrms at input grid; and those are not going nutz with 2Vrms at grid are rare as hens teeth
- they (majority) are not made to have 2Vrms at input; they will sing, but having greater THD than Papa's H2 and my SissySIT combined
Where would one find these hens teeth?
I have a small stash of 5814/12AU7/E80CC tubes from other preamps I sold long ago that but was hoping to use in some circuit to drive the F4 at some point. Didnt like how they sounded...kept the tubes.
And yes, I know its bad practice/form to start with a specific part like this and ask to be pointed at a circuit. If I cant use them...is what it is. It wont stop me wanting to run an F4 with glowing bottles. So to that end, other than Impasse, what tube preamp could be considered happy with 2vrms in....and is this even the right thread to ask the question????
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I'm not quite there yet.. but these days I'm headed towards an AVC attenuator in front of my high gain tube pre. The toobz provide some euphony, and the inductive attenuation eliminates the SQ robbing qualities of any resistive control and keeps us from abusing the poor grid with too much voltage. Then I pick something out of my LEGO pile of front ends and follower output stages to create something with ~12-15 db of gain to finish the chain. Seems to work quite well. And things like AVC's and glowing bottles should help with entry into Rome at that final checkpoint.... would be unfortunate to make that long trip and be denied at the border after getting oh so close....
Thank you! I looked up the prices of some of those tubes these days…mind boggling. Really hoping I can give a few of them a workout in an appropriate circuit.Sure, try an EF84 pentode gain stage followed by a 12AU7 as a White cathode follower.
Enjoy
I have several populated pcbs of "new" projects, waiting for bench time
Already started forgetting what's on pile .........
Go figure
In short - everything is possible, even Wooden Stove ............ while I'm sometimes short with time (or brain) just to comment something, let alone work on it
I'm sure Boyz in Tube Forum are having somethin cooked and we didn't spot
Tube Lab George and other Boyz
Already started forgetting what's on pile .........
Go figure
In short - everything is possible, even Wooden Stove ............ while I'm sometimes short with time (or brain) just to comment something, let alone work on it
I'm sure Boyz in Tube Forum are having somethin cooked and we didn't spot
Tube Lab George and other Boyz
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