New to AG Question about going from 6V6 to 6L6

[theundeadelvis]

Hello all! I'm new to the Amp Garage, and this place seems full of great info. I've built a few amps recently, one of which is a clone of the Matchless Lightning. Right now it is set up to use either 6V6 power tubes or EL84 tubes. I'm curious how easily it could be adapted to use 6L6 tubes? If I do this I assume I would no longer be able to use the 6V6s or EL84s. I like the flexibility of being able to use different tubes, but at the same time I looking for a little more clean headroom, and I thought the 6L6 tubes might be an option. Thanks in advance!

[Richie]

If the amp is set up to run 6v6s, it should run the 6L6s,or the socket will be ok for them.. BUT.. alot depends on the PT and OT your using, the 6L6 will be a bit more current, and if your OT is a smaller rated one, you may not get a big difference in output,or be worth trying it. Do you know the ratings of the transformers?

[dartanion]

This also should not negate the ability to run EL84s.

Still hanging at the 18watt?

[theundeadelvis]

Hmmmm, I don't know the transformer ratings off hand, but should be able to get them. The PT is a Heyboer and the OT is the Matchless OEM. I'll have to dig up the ratings. I've read a couple of other posts where people have done this to other amps, and they talked about the output being at a different impedance. Will this be the case? Thanks again for the input!

Dartanion-yep, I still frequent 18watt also, and PPwatt, SEwatt, metro amps, AX84, and diystompboxes. I think I have a problem.

[theundeadelvis]

I was told the OT was rated for 18watts. I got them from Dockery and he thought I would have to replace the PT and the OT and then re-bias. Bummer.

[Noel Grassy]

In terms of the PT I might add that filament current is a concern especially if EL-34's are applied.

[Darkbluemurder]

I was told the OT was rated for 18watts. I got them from Dockery and he thought I would have to replace the PT and the OT and then re-bias. Bummer.

As regards the PT heater current is the issue. 2 6V6s need 900mA. 2 EL 84 need a bit more. 2 6L6s need 1800mA. And 2 EL34 or 6550 need 3000mA. If it was designed for 2 EL84 is could just about work with 6L6s depending on how much margin the designer implemented. You should get the heater current rating for your PT from the manufacturer or dealer.

As regards the OT: 18W is a bit small for 2 6L6s but Neil Young used 6L6s in his Tweed Deluxe and it worked for him - although I don't know how realiably!

I would stay with the small tubes.

[dragonbat13]

You could put in a stand alone heater supply

[dragonbat13]

your output tranny with 6l6s probably wont give you the headroom. It will saturate I would think

What does everybody think about running some 7591 tubes instead of 6l6?

[theundeadelvis]

I'm not familiar with 7591 tubes? But I am open to any suggestions.

[brownnote]

Yes you can do it, provided you have enough heater current, a standalone filament transformer is a good idea.

6L6's will saturate an 18W OT but you'll still have more headroom and volume.

7591 is a cool tube but it's not going to work with this setup unless you re-wire the sockets (because it's a different pin out) and the B+ voltage is low enough.

[theundeadelvis]

Where would I find resources on using a stand alone filament transformer? Thanks again!

[dragonbat13]

Dan torres has a book that will teach you. Most people dont like his work but I feel that the heater supply is a good idea.

Get a book

I dont know what a good book is but you need one.