The green/blk box sylvania 6ag5 with the dark carbonized glass are absolute gems in a line stage. Every time i compare it to other 6ag5, or really any other kind of tubes i have now they re-blow me away. I've been combing ebay for them for a bit now, have bought several matched pairs now too, and they are all in an entirely different league then anything else i have when it comes to soundstage presentation. even my 12ax7 circuits feel flat and dull to me now that ive gotten used to these little TV tubes. Im only running barely over 100v across the plates. They no joke feel twice as big in every direction as any other tubes i have. Some of you older tube and radio guys may have em lying around too maybe. Thats how i got my first box em them. Wish it had more of these one's though lol.
As triode > pentode as well for audio. More gain (if you need it), less THD, and a sounstagier soundstage (lol)
The linestage design im using is attached because why not. Forgot to draw the output off the coupling cap, but whatever lol.
Tube pic just to show what i mean by dark glass. They arent used. All the old green/blk box sylvania 6ag5 tv/radio tubes look like this. All have carbonized glass, but some have black plates some dont. They all sound unreal though. Some of the yellow box sylvania 6ag5 have crbonized glass, some dont, i havent tried any of them yet but have some on the way.
I'm a beginner with amp design and tubes. But i've been training an ear in the mixing and mastering side of things for quite some time, and i know an impressive soundstage when i hear it. These dark glass 6ag5 as triodes are pretty nuts. The more i learn and play with, the more i feel like i somehow lucked out and stumbled into a hidden gem right off the bat or something. Nobody uses these for anything unless they have an old radio that uses them, and most my 6ag5 are pretty nothing special tubes... But man, these dark glass tubes are a newfound love like i haven't had in audio in many years. Spec for triode class A operation is right on the data sheets for them too. When it comes to some other tubes (cough* 12ax7 cough* cough*), a set that sounds like these do is not cheap. These run about $10-15/matched pair, ive bought a few pairs on ebay already. I got a lot of 9 of them with 2 matched pairs in it for $20 shipped. The box of 6ag5 given to me free had 12 of these sylvania's in it. Won't be long and ill have enough for the rest of my days. (Maybe some of you have some and dont want them
)
As triode > pentode as well for audio. More gain (if you need it), less THD, and a sounstagier soundstage (lol)
The linestage design im using is attached because why not. Forgot to draw the output off the coupling cap, but whatever lol.
Tube pic just to show what i mean by dark glass. They arent used. All the old green/blk box sylvania 6ag5 tv/radio tubes look like this. All have carbonized glass, but some have black plates some dont. They all sound unreal though. Some of the yellow box sylvania 6ag5 have crbonized glass, some dont, i havent tried any of them yet but have some on the way.
I'm a beginner with amp design and tubes. But i've been training an ear in the mixing and mastering side of things for quite some time, and i know an impressive soundstage when i hear it. These dark glass 6ag5 as triodes are pretty nuts. The more i learn and play with, the more i feel like i somehow lucked out and stumbled into a hidden gem right off the bat or something. Nobody uses these for anything unless they have an old radio that uses them, and most my 6ag5 are pretty nothing special tubes... But man, these dark glass tubes are a newfound love like i haven't had in audio in many years. Spec for triode class A operation is right on the data sheets for them too. When it comes to some other tubes (cough* 12ax7 cough* cough*), a set that sounds like these do is not cheap. These run about $10-15/matched pair, ive bought a few pairs on ebay already. I got a lot of 9 of them with 2 matched pairs in it for $20 shipped. The box of 6ag5 given to me free had 12 of these sylvania's in it. Won't be long and ill have enough for the rest of my days. (Maybe some of you have some and dont want them
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Only my view; Generally, I found Syvania video line tubes often rather noisy; partition noise in pentode & microphonic for audio. Currently, I am using the 12BY7/HG7 (have loads of them) as audio diff drivers and had to spend several evenings sorting out to get reasonably matched pairs (best set up as triodes, nice with 25dB gain). After much sorting found the Philips ECG version the most consistent performers. GE did also well, but RCA and other brands were rather noisy and microphonic. But makers for these didn´t stipulate these types to be used for audio, so didn´t strive for min noise & mictrophony in the 1950´´sand 60´s TV market, unlike the later ECC8xx series specifically for the audio market end product.. What I have found that tubes for TV (often having larger cathodes) are best run at somewhat higher currents than other types, as after several days stabilizes the characteristics.
Keep at it.....it´s all a great kudos & curiosity!
Bench Baron
Keep at it.....it´s all a great kudos & curiosity!
Bench Baron
Try http://www.mcshanedesign.net/ His contact adr is quite a long way down the page.
12BY7..........nice tube, less transconductance than the HG7. Pity that both don´t have internal shield screen.
BB
12BY7..........nice tube, less transconductance than the HG7. Pity that both don´t have internal shield screen.
BB