@william2001
there are enough gain stages around here, and fact of having active gain stage is sorta excluding any reason to have autoformer afterwards
now, why majority of presented gain stages are somewhat half done ( not entire package, sans dedicated PSU) is another issue; we can talk about (objective) logic behind that, but that's the fact
on the other hand, I have enough cringe dealing with anything having common resistive volume attenuator, but that's only me and my own OCD
even I'm aware of fact that when you have only an oven, you can't put ice cream inside; I mean - you can, but it'll not last long
there are enough gain stages around here, and fact of having active gain stage is sorta excluding any reason to have autoformer afterwards
now, why majority of presented gain stages are somewhat half done ( not entire package, sans dedicated PSU) is another issue; we can talk about (objective) logic behind that, but that's the fact
on the other hand, I have enough cringe dealing with anything having common resistive volume attenuator, but that's only me and my own OCD
even I'm aware of fact that when you have only an oven, you can't put ice cream inside; I mean - you can, but it'll not last long
Dear Zen,
Brain on Rad and Chemo makes for a dull boy!
Thanks for the links!!!
sad to read that; wish you all bloody damn luck
even more reasons to enjoy in reading and building
Built multiple BA-3 Preampsto experiment with. Whammy and Korg are a little light for this war. Otherwise in house fantastic. Have Pass FE to play with as soon as I figure that out. Waynes Linestage is next up.
2 SE Zen Iron Pre's to play with when they come in.
Experimenting with differant attenuators.
I keep hearing about your love of autoformers. Maybe I will try that if maxed out BA-3 is weak.
Still have to get to the woodshop and build cabinets for the speakers. If, and I have not yet lost this range war Keystones are up. All this was to go to my shop but that stopped.
Werking in a damn bedroom with bed as a workbench.
So, all that I glean from you is a blessing! Keeps me focused.
Danke Zen Mod.
2 SE Zen Iron Pre's to play with when they come in.
Experimenting with differant attenuators.
I keep hearing about your love of autoformers. Maybe I will try that if maxed out BA-3 is weak.
Still have to get to the woodshop and build cabinets for the speakers. If, and I have not yet lost this range war Keystones are up. All this was to go to my shop but that stopped.
Werking in a damn bedroom with bed as a workbench.
So, all that I glean from you is a blessing! Keeps me focused.
Danke Zen Mod.
It makes me sad. I've been restoring them and had to give up my shop I was building. They are outside since and I don't have the strength to redo them. I just hope I can get some of them on power again to finish what I've started here. If not I make chips by hand as I've been forced to do.
I have been a heavy machinist all my life and now having to sell or scrape it all. Nobody wants or understands this history. Or the skillset to run them. Most of these Manufacturers have bought back the machines in time and scrapped them due to lawsuits.. What I've collected sliped through the cracks of time.
This is the new "America". Useless.
I have been a heavy machinist all my life and now having to sell or scrape it all. Nobody wants or understands this history. Or the skillset to run them. Most of these Manufacturers have bought back the machines in time and scrapped them due to lawsuits.. What I've collected sliped through the cracks of time.
This is the new "America". Useless.
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Iron Pre Turbo Balanced.
20db gain.
To drive bridged F4s.
Because sometimes the First Hundred Watts are important... not just the First Watt.
I know you keep saying stuff about the "right speakers", yadda, yadda... but sometime, SOMETIMES, the "right speakers" barely move with one watt.
I've tried, trust me... 35 watts... not enough. Sometimes. 10 watts? pfftt... good for medieval lute concerts, maybe.
Power corrupts, 200 watts of power really corrupts. ;-)
No, I can NOT afford a PL XS300.... I'm not a Rich Boy.
Oh, don't forget... RED LED.
Oh, why F4? Why not? Because they're there. A life without challenges is a boring life. I don't like Bose.
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see here, post #98 https://www.diyaudio.com/community/threads/the-marriage.390965/post-7154543
build Boo, with Edcor PC600:15K at input; that will be 5V/V gain
connect Iron Pre Bal in front of it, having 2V/V
sum is 10V/V gain, 20db exactly
pure Square Law bridged OS will run your Maggies with no sweat
if I didn't post Gerbers for said combo, just say
while we are at it, considering that I already posted Gerbers for Boo and Pooh, if Boyz want them for Store (more, the merrier, bigger headache), I have no objection
nota bene - I'm lazy to check data for Edcor - how much of distortion they'll have swinging 80Vpp, I can't say
but, whatever they distort, maybe you'll like that
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they're declared with 5Vrms max input
80Vpp at output .......... /2, /1.41 means 28.28Vrms
/5 means 5V65rms at input ....... which is just a smidge above declared
Not sure how the solution would be implemented, but perhaps one piece only has to swing 40Vpp (one half of the differential signal)??? If it's like your solution for Iron Pre (creative use of the windings within one piece to handle both signal halves) ... then ignore... I could be off in neverland.nota bene - I'm lazy to check data for Edcor - how much of distortion they'll have swinging 80Vpp, I can't say
but, whatever they distort, maybe you'll like that
Either way... just fun learning / watching for me and understanding completely that double iron can add mucho cost...
FW SIT-3 / SissySIT are great but just flat out don't have enough gain and I grew tired of sticking separate gain stage boxes in front of it... another chassis, more cables, more complexity, blah blah. I like the transformer passive VAS concept (I think it sounds better at +6db) and wanted to keep it in the chain, despite a couple of drawbacks. And I want the ability to swing the output stage rail-to-rail. I want the output stage to clip before anything else does, to get all the power I paid for. Meaning you really need something like boosted rails / bootstrapping on your +20db active stage after we throw the transformer in the trash bin, that would have given us that needed "boost". So, that's my reasoning for an active gain stage driving a passive one (applied conservatively and wisely).. But, maybe I'll change my mind tomorrow...