Need tube help: 5881, 6L6, 6L6GC, 6L6WGB, etc....

[mrgp52tele]

I am looking for a pair of 6L6 tubes for my 73 S/F Super Reverb. I play Classic Country (i.e. the Bakersfield Twang) and I need tubes for a clean sound with a lot of "headroom", not really looking for distortion (I have another amp set up for that). Any help you can give me will be appreciated.

[skeksis]

I may remember the exact details wrong, but this is the general idea:

I think your amp needs 6L6GC, which is important because that version is a high-spec tube that can take the voltages found in BF/SF Fenders... Most of the other 6L6 varieties would be in trouble in your amp.

6L6 = Metal can (intro specs, pretty low output, I think 19w)
6L6G = Big glass shoulder bottle (same specs as metal type)
6L6GA = Smaller glass shoulder bottle (same specs as metal type)
6L6GB = Straight side glass bottle (same specs as metal type)
5881 = Small straight glass, upgraded specs, I think to 23w - note that newer versions are somewhat different
6L6WGB = pretty much the same as 5881, at least originally...
6L6GC = Straight glass, upgraded to 30w, MOST modern varieties are close these.


That's the basic idea, anyway. Some good 6L6GC's (maybe old stock if you can justify the cost) would surely get you in the ballpark of what you're looking for.

[mrgp52tele]

Thanks, all new to me..............so my S/F Super Reverb is 45 watts, so when you talk 23 watts, and 30 watts, are you saying per tube (i.e. 23 watts x 2 tubes= 46 watts and 30 watts x 2 tubes= 60 watts)?

[mrgp52tele]

I'm thinking about these: SED SVETLANA WINGED C 6L6GC. I would love to have a set of NOS but they are $$$$. If I do find a set I can aford, they tend to be 8551's.

[redstringuitar]

Originally Posted by mrgp52tele

Thanks, all new to me..............so my S/F Super Reverb is 45 watts, so when you talk 23 watts, and 30 watts, are you saying per tube (i.e. 23 watts x 2 tubes= 46 watts and 30 watts x 2 tubes= 60 watts)?

Yeah, it's wattage per tube, but your amp may be rated at less than the total output of the tubes...it all depends on how the amp is configured to run.

I use winged C 6L6's, arguably the best production 6L6, certainly a big improvement over others I have used.

[Cleeve]

this is good if you haven't seen it already, some reviews of the different 6L6 variants available today..
http://thetubestore.com/6l6review.html

[marshman]

I think those wattage figures actually refer to the internal parts ability to withstand heat generated by the flow of electricity through it's internals before melting down, measured in watts, like a space heater.

As it turns out, those figures are very similar to the power they're capable of, but coincidental.

Svetlana, the real, WING C "=C=" ones, are frequently mentioned in the 'clean headroom' stakes, though I've never had the opportunity to try them. I have tried JJ 6L6GCs with good success and tons of power, if you're inclined.

[redstringuitar]

Originally Posted by marshman

I think those wattage figures actually refer to the internal parts ability to withstand heat generated by the flow of electricity through it's internals before melting down, measured in watts, like a space heater.

As it turns out, those figures are very similar to the power they're capable of, but coincidental.

Svetlana, the real, WING C "=C=" ones, are frequently mentioned in the 'clean headroom' stakes, though I've never had the opportunity to try them. I have tried JJ 6L6GCs with good success and tons of power, if you're inclined.

I knew it was something along those lines, just wanted the OP to realize the figures were per tube.
The =C='s are good for clean and overdriven sound, I use a 5751 PI and JJ ECC83's, which actually tames the gain a bit and sounds all the better for it...it's all horses for courses though.

[Andy B]

I really like the sound of Sovtek 5881 Wxt's in Blackface & Silverface amps. They seem reliable also which is more than I can say for some of the others out there. I personally use them in a 71 Pro Reverb & a 73 Bandmaster Reverb. Set the bias around 33ma & they work great. They seem to fine biased anywhere between 30-40ma.

[Demo]

Moved.

[jefrs]

My Epi BC30 is designed for 5881 but came fitted with a pair of quite nasty and brittle Sovtek 6L6WXT+. I've tried NOS Svetlana Winged=C= 6L6GC in there and found them very clean (head room) but rather sterile. Currently fitted with NOS Philips JAN 6L6WGB (aka 5881) and there are very nice. (but see skeksis above, it looks like later military and soviet 5881/6L6WGB/WXT can take more volts than a 6L6GC being designed to run motors and the like, I've seen some spec'd to 800V).

You can put a 6L6GC into an amp built for 5881 but not a 5881 into an amp built for 6L6GC. Except you can, it will work but may not last as long depending on whether it is original or later spec. Select by ear. Biasing being another matter.

When two valves are used in push-pull you can get close to three times the power output of one valve. You never get the maximum rated output. The BC30 is rated about 30W in pentode (? they're beam-tetrodes) mode, but I suspect more because it is almost too loud even in '15W' mode (I was asked to turn down so the ss Marshall could cope).

[mad dog]

JJ 6L6GC are a good, reasonably priced bet in that amp. Loud, big headroom. I ran a set of 6L6WGB NOS Phillips in my BFSR for years. All it took was a rectifier change. Excellent sound. My other fave choice here is not cheap, 7581A. It's a military spec version of the original Sylvania STR 387 (hope I got my facts right) ... these are the highest output 6L6GC. Certainly plenty of headroom.

[jefrs]

+1 regarding the rectifier, one that's even slightly crocked will ruin the amp's performance.

[randysmojo]

I am using Sovtek 6L6WXT's in my Twin Reverb. Very warm tone, and supposedly something like 20% more clean headroom than the 5881WXT. All I know is in this Twin, it is clean until the windows rattle!

[wetland10]

I use a pair of Tung-Sol 5881's in my Bassman and it has never sounded better. They are great tubes. Not exactly clean, but a great tone.

Wayne

[Mik]

Phillips or GE 7581A, the max headroom 6L6 type tube. NOS or (used) OOS. Worth it.

IMO the 7581A is THE Super Reverb tube.

Mik

[tonebro]

As Mad Dog said, 7581As and you're done. The absolute best tube for what you describe for your needs.

[randysmojo]

So what would be the lowest output 6L6 style tube? I have a twin reverb that of course is very loud. I don't need it to overdrive, just warm clean tone that I normally get at just above 3 on the volume. Unfortunately some stages require lower stage volume. The amp sounds fantastic when you can run it at a little above 3 or more, but I need that tone at lower volumes. Has anyone put 6V6 tubes in an old Twin Reverb? Would it sound pretty much the same tone but lower levels, and what mods have to be done to make that work? Otherwise, is there a lower output 6L6 type tube that might cut it?

[skeksis]

I've never done it, but I'd guess that 6V6 in a Twin wouldn't be pretty & might be a disaster.

Those lower spec glass 6L6 types (6L6GA/GB/5881) might stand a chance, at least for a time, but I wouldn't bet on it.

If you really need a quieter Twin... you should probably pick up a Deluxe Reverb :-)

[Cleeve]

YOu can run a twin on just two tubes, either the inner pair or the outer pair, never two on one side if you know what I mean. 6v6 tubes cant take the voltage a twin dishes.