Biasing TAD 6L6WGC

[dallyd31]

Should I treat these as 30 watts or 23 watts ??? I just biased them, treating them as 30 watts. They have a plate voltage of 465, so I biased the at about 41 ma. (65%) Is this about right ??? Does anyone have any experience with these and at what bias they sound best ???

Using these in a 59 Tweed Bassman clone.

[rockon1]

Everything I could dig up indicates they are 30 watt tubes. That said I doubt I'd run them that hot. I'd try them down at 35 ma or so and see if they sound as good running cooler. Heres an old thread on the subject. Bob

http://www.thegearpage.net/board/sho...d.php?t=213245 (http://www.thegearpage.net/board/showthread.php?t=213245)

........

[5er Driver]

Ask TAD, they speak English. I deal with them all the time. Excellent service. They are open on Saturdays, you may get a reply back today.

http://www.tubeampdoctor.com/request_for_service.php?message_to=service

[teleman55]

I got some. Bias 'em like a 30 W 6L6GC. That's what they are. Nice tubes.

[Blue Strat]

Does anyone have any experience with these and at what bias they sound best ???



60% max for ANY power tubes.

Only you can answer the question about "what sounds best". Try from high 20s to about 40mA and see what you think.

[slider313]

If you bring them down to 30-35ma your plate voltage will be a bit higher. I'm not sure if they,TADS, will withstand the higher voltages.

[GearHeadFred]

If you bring them down to 30-35ma your plate voltage will be a bit higher. I'm not sure if they,TADS, will withstand the higher voltages.

I would think the 10-15 extra volts would be easier on them than the extra 2-3 watts idle dissipation in the long run.

[slider313]

I would think the 10-15 extra volts would be easier on them than the extra 2-3 watts idle dissipation in the long run.

Only one way to tell, run them at 35ma and see what you get. He said the amp is running 465v@41ma so you could very well see 480v+ I would be concerned running any Chinese power tube at those voltages, only because I had a pair of KT66's go up into a blazing light show at 42ma@482v in a brown Fender Concert. So it could just be my bad experience.

[GearHeadFred]

Only one way to tell, run them at 35ma and see what you get. He said the amp is running 465v@41ma so you could very well see 480v+ I would be concerned running any Chinese power tube at those voltages, only because I had a pair of KT66's go up into a blazing light show at 42ma@482v in a brown Fender Concert. So it could just be my bad experience.

You were at 81% (20.2 watts) of 25W with that bias setting.

[slider313]

You were at 81% (20.2 watts) of 25W with that bias setting.

I believe the KT66 is a 30 watt tube and 70% would be 43ma at 482v

[ChickenLover]

I'm not sure if they,TADS, will withstand the higher voltages.
FWIW, when I was looking to get tubes for my SLO homebrew I looked into (and purchased) the TAD short bottle 6L6WGC. I was told (by a reputable tube dealer) that both of the TAD 6L6 tubes have the same max voltage rating of 500vdc. They've been fine in that amp but it's only ~465vdc and it's only been a month or two. Sound good though.

[GearHeadFred]

I believe the KT66 is a 30 watt tube and 70% would be 43ma at 482v

I'm not an expert on KT66s but the few datasheets I looked at on the web show 25W max, with the JJ showing 27W max.

[INX]

60% max for ANY power tubes.

Only you can answer the question about "what sounds best". Try from high 20s to about 40mA and see what you think.

I can't believe that statement is optimal universally. JJ's and Sovteks don't sound good in my amp until they are WAY over 60%.

[rockon1]

60% max for ANY power tubes.

Only you can answer the question about "what sounds best". Try from high 20s to about 40mA and see what you think.

+1 Too much "hotter is better -70%" throw about on the net. Ive yet to hear a difference for the better this hotter setting. Well actually my Supersonic got harsh/brittle at around 70%. Why cook them if its not beneficial. Bob

[jetlag]

I emailed TAD a few years ago and they told me the 6L6WGC (short bottle) was a 30 Watt tube. They also indicated that if you had a 7581A application they recommended their 6L6GC tall bottle tube, but didn't go so far as to say it's a 35W tube.

[phsyconoodler]

I use the TAD 6L6WGC short bottles in my V-Verb amps and they get pounded weekly by Johnny V(canadian blues artist)and he hasn't hurt any after 3 years of pounding the living daylights out of them in two amps.
He plays LOUD.A Gibson Firebird into a V-Verb with TAD's is a thing of beauty.
Go listen on my website. www.claramps.com (http://www.claramps.com) the clips are with TAD's.

[scottl]

I have had the TADs at 500v plate with no issues.

[tejastubes]

I would recommend 30mA on those because on the new production 5881 types you just don't want to go up too hot. I like 5881 (6l6wgb) biased around 30mA for my ears.