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Help With 6Y6 amp

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I think this tube could be a winner. It seems to have been developed for voltage regulators since I just bought an old Lambda one yesterday with 5V4 a regulator tube and other than the 2 6Y6s a couple of amplifier triodes (mini singles with octal base) and the black crackle paint etc, this thing says WWII to me.
I see that DecWare has a SE 6V6 that will also take 6Y6 tubes for rolling. See the Mini Torii, there is no schematic and also voltage regulators in parallel to the main voltage path, not in it, so this is not a simple SE amp for the weekend tube warrior.
I found a nice SE 6V6 schematic (maybe here) and have used it for the basic map, but am math challenged meaning no Ohm's Law and truly I do not understand all the stuff my GE book tells me.
Basically this would be a very simple amp. If you take one side, forget about the power supply which I want to put on a separate chassis so I can make changes to it later and use different output tubes, as in one chassis for 4 Pin Triodes and another for Octal Pentodes, but all running fairly close together with maybe switches to change the B+ as this is ALL about tube rolling.

Basic amp is a 6J5G and/or GT as the amplifier and a 6Y6G and/or GT as the power tube. I bought a pair of James J123HS which has 3 primaries and 3 secondaries. 2.5K to 5K ans 4 to 16 ohms. Doing SE the list of triodes and pentodes you can run on this is as long as your arm, but I figure the 6Y6 and 6J5 are about as easy as it gets. The 6J5 takes 300V to the plate and the 6Y6 takes 200V to the plate. The 6Y6 seems to like an impedance of 2K to 3.5K but most tube data shows 2.5K. The J123HS lets you play around a lot.

I want the help of a math wiz to help do the values, everybody else to think of tubes that can be use easily with what ever power supply you have. I have a military potted with 335V @.125A with 5V 2A and 6.3V at 2.1A so I want to use tubes with 6.3 filaments.
6A3s and an equivalent 6B4 are still available at reasonable prices which means you can buy a pair of NOS for the price of 70s Russians or never had dust on them Chinese.
The 70s Svetlana 6B4Gs are going for really good prices on Ebandits, so if you have some pairs of old 6V6s, 6L6s EL34s, 6550 and if you want to buy a filament transformer that lets you play with 300Bs, 45s etc go for it. I plan on getting there but there are plenty of 6.3 volt fils to keep me busy.

By the way 6Y6Gs should cost about $10 for a matched pair plus shipping. Buy a flat and they are $3.50 each. That is for a pentode from the 40s and in SE, Class A they put out around 6 watts, which is just under a 300B and triple a 45. If you are running efficient speakers they will provide plenty of power.

Use the summing circuit that Fisher put in their integrated and receivers and you can slave a sand amp to run subs if you need those 20 Hz notes to tickle the endorphin center in your brain.

Anybody want to help me out? Get in on the fun? Want to find out how many watts can be gotten out of a triode strapped 6Y6 and if 2.5K is low enough to still get pretty music out of it?

Thatch
Bassomanic! To you early SNL fans!
 
Just another thought that I forgot to add. I know that for most of the time NFB is not wanted, or if you are doing just acoustic instruments just a touch is a nice thing, so I am planning on putting a stepped attenuator of say 0 to 10K and running NFB with the ability to use it or not. Too much you have an oscillator but sometimes having a bit in there can help get a richer sound out of the 2 to 8 watts you are playing with.
An old friend built some SE amps that would take basically everything in the 6L6 family and everything in the 12AX7 family and he added a neg feedback with the ability to change it, have none, what ever you want and I thought it was a great touch. I plan on doing it to mine, just forgot to mention it before.


Bassomanic!
 
The 6Y6 is a good tube. A little heftier than the 6V6 but at lower plate and screen voltages. Triode connected with 200 volts B+, I would expect the tube to produce about as much as a pentode connected 6V6.
I've been experimenting with a few output tubes as well.
Power triodes and beam power tubes.
 
If I recall correctly, Acrosound made a transformer specifically for the 6Y6, and really sang the virtues of this tube. Yeah, it was a PP design, and UL to boot, but I think they were getting about 18 watts out of a pair, at rather low B+ levels, using cathode bias. The low plate-to-plate impedance required allowed for a rather extended HF response as well.

Dave
 
I bought some James OPTs that have 3 primaries, I still haven't found a SE 6Y6 schematic. Without a triode strap they are rated at 6 watts, which is about where I want to be. Triode strapping is sometimes worth the loss of 3 db, I would have to find out if it would be enough for my speakers. At everyday listening levels I would say yes, but if I want to listen to Yes, I doubt it.
The Acrosound UL PP aught to be good. The only ones I am familier with are the 300s which were made for 6L6 type pentodes. Allen Organ amps are a good example.
Thatch
 
I enjoyed this amp for about 6 months before I changed things. I preferred the UL connection.
Here's what I used.
 

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