Germanium audio preamplifier

Hello,

I have a few Germanium transistors. (AC Series) firstly you want to make good audio preamplifier. I have found the attached diagrams. which one should I choose. If you have a better scheme, please write

sorry for my english :)

Best regards.
 

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Cannot disagree on Time takes it's till in ecosystematic progression line, yet it is not amoral to use germanium tranzistors for several purposes either, and in a meanwhile claim it is better for one's ears.
My bet is that germanium will be better for those who are getting detached from reality and feel like germanium sound represents this home with audio in middle of nowhere filter.
 
I suggest you sell them to somebody who has a Vox organ or other masterpiece that really needs germanium. New builds should use silicon, 1000% more stable with temperature rise.
I own a Shober recital organ with lots of germanium, and it came with a little box of dead germanium transistors & zener diodes. I've been redesigning circuits to use silicon, not that hard really. Upgrade and forget it, IMHO. The gold key "forever" key contacts on 32 pedals & 122 keys are the main reason I mess with it; also no rusted in tuning slugs like Rogers. I could have bought a 3 manual Rogers, but it wouldn't fit through the door.
 
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adason

Member
Paid Member
2004-11-10 8:31 pm
Maryland
they come with long legs :)

I have an old phono preamp full of germanium transistors, from a recording studio, with balanced output with transformers...after I recapped it, it sounds great and has nice pleasant musical distortion i like. I got dozen modern phono preamps, but this germanium one i keep just for that special distortion it has.
 

U230421

Disabled Account
2017-02-07 1:54 pm
Just a few km's around the corner from my place, there is this 'junk-shop' with heaps of overstock from nowhere, and in a dark corner in the deepest cave of this partslabyrinth is a 'wall' with endless little trays in it. OA... diodes, AA..., AC... & AD... transistors. Hundreds of them.
Thanks adason for the hint! I'll make an attennuater buffer to sit in between the chain.
Let's see, Vbe is some 0.3V, so that's different...
 
Just a few km's around the corner from my place, there is this 'junk-shop' with heaps of overstock from nowhere, and in a dark corner in the deepest cave of this partslabyrinth is a 'wall' with endless little trays in it. OA... diodes, AA..., AC... & AD... transistors. Hundreds of them.
The only guitar amp shop I know of that sells them, the little transistors for vox organs, is getting $10 apiece. I'd take a DVM over to this junk shop, check a couple, and make an offer. Ebay shop could be in your future.
 

U230421

Disabled Account
2017-02-07 1:54 pm
..."(a) good audio preamplifier." Not a pleasant distortion generator...


This is the challange: a (reasonable) good audio amplifier using GE semiconductors. We can shoot, make funny remarks, suggest possibilities, go astray and everything. There are zillion designs to contemplate, uncountable discussions about pro's and contra's.
I dare there not so many on this platform or beyond who can or will try to design from scratch a decent preamp, let's say from 150mV~ to 1.5V~ with a volume pot, only GE.

Let rediceman tell me what AC types are on the table.
 

U130421

Disabled Account
2015-12-16 2:00 pm
From a listening point of view, germanium might be better than silicon. At the moment I am listening to an all germanium portable radio that was popular in the '60's. Sounds great, better than any silicon equivalent.
With 0.2v instead of 0.7v , the crossover distortion in low power amplifiers the germanium is much better. 2SB324/2SD352 were the best for portables .
 
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Would have to suggest that if you want a "good" quality pre you use modern good quality parts. Old germanium diodes and transistors worked for the time, much better are available now.

Hello Starkeyg,
Of course we know about silicon :)
please see topic says Germanium not silicon.
Because germanium devices have much more colorful sound for me.