5881- 6l6

[richwalters]

Can anyone recommend todays best manufacturer who makes consistent reliable tubes?

richj

[Eli Duttman]

SED flying C (=C=) 6L6GCs.

[James D.]

Agreed,

Having just gone through this process and found SEDs were noticebly superior to other makes other than NOS ones. I had SEDs from three different batches bought over the last ten years and all were very good or better and biased up within 10% of each other. Interestingly the best sounding ones were the latest ones.

Also interestingly they were the best for audio or for guitar amp usage...

ciao

James

[tubelab.com]

Any long term reader of this forum knows that I can be tough on tubes. I routinely test tubes at power and voltage levels far in excess of the published ratings to find out which types will give good service and good sound in a customers amp.

I have tested a few 6L6GC types and come up with two winners. The previously mentioned "Winged C" by SED has proven reliable in HiFi and guitar applications. Good sound too. I have had bad luck with their EL34's though. One DOA and one infant failure out of 4 tubes.

I have used about 15 Winged C 6L6GC's over the past 2 years. No filaures have been seen. Beware the "Svetlana" branded tubes, these are actually made in the Reflector factory as are Sovtek and Electro Harmonix tubes. They may be good tubes but I have no experience with any of the recent vintage.

About 3 years ago I re-tubed a Fender Bandmaster. I pulled out a pair of "Ruby" brand Coke Bottle (ST) shaped 6L6GC's. They were still good, so I saved them. I have since stuck those tubes into every 6L6 capable amp that has crossed my bench. They just ROCK and have no problem with 475 volts (plate and screen) or 35 watts dissipation. I have seen these tubes sold under several names, but they appear to be Sino - Shuguang tubes. Antique Electronics Supply used to say "We couldn't blow up this tube no matter how hard we tried". Unfortunately they no longer sell them. I have found them on Ebay for under $3 each. Item # 150040333575. I bought some from this seller with no problems. At Under $5 each with shipping, I can afford to abuse these so I do. I find that they sound really good in my SimpleSE amp operating at the point where the plates just begin to glow. I have the original pair that I took from the Bandmaster in the amp still with 4 months of daily (dull glow) operation on them.

I have tested these at extreme power levels without failure. The picture shows the SAME tubes (removed from the Bandmaster) running hard at 45 watts of dissipation. Note the even orange glow. This is good. Tubes that show hot spots tend to die rapidly when abused. The room lights were off when the picture was taken, but the tubes were definitely hot. I wouldn't expect them to last long at this level, but many tubes would just instantly arc over and die. These are the same pair of tubes that I still use in my amp. The picture is 6 months old, the tubes still ROCK on.

[richwalters]

Yes ...thanks for replies......to get even anode glow throughtout the entire length of the anode is a good test for consistent manufacturing. My MI amp had a set of Ei KT90's which started glowing in the middle and one side for no reason so I'm going to drop them and fit 6L6's and fit jock straps. Fortunately I can drop the B+ and use a different tap on o/p tranny. .
.
My 75W quitar amp is filled with 807's (Kenrad) and tubes still going strong after 44 yrs service. The rest downstream is good old 6SN7's and 6J7's Can't complain. Keep plucking.

richj

[mr2racer]

Hey tubelab,

Does that recommendation for Ruby tubes hold true for audio amps as well?

[Gobble]

How are the 6L6GC/STR 387 Sylvania and G.E 7581a ? Worth a buy?

--G0bble

[mr2racer]

I have a collection of NOS 6sn7's. I need two good tubes for the amp I intend to build. I have two RCA GTB's, one CBS, one Sylvania, and one GE. I also have one GE GTA, one Sylvania GT and one Zenith GT. All these tubes are NOS and tested great. The obvious choice is to use the RCA GTB's because I have two. But if one of the others is inherently better it might make sense to buy one to match?

Kevin

[DigitalJunkie]

I can't comment on the sound,but the Shuguang 6L6GCR tubes I have on hand can take some abuse and keep on playing! I've run these at ~640V+ in UL mode,and they didn't go nuclear. When you turn up the dissipation the plate glow seems pretty even also.

They're cheap enough to try out.

[vinylkid58]

Unless you need the extra plate dissipation of a"GC", there's nothing wrong with the Russian 6P3S-E.

jeff