Do all guitar amplifiers that use the 6L6GC tube sound the same all things being equal? After all, an electric circuit only regulates voltage from a wall outlet does it not....
@laterallateral They may have some value to vintage radio and audio collectors. NOTE: The 6L6G is NOT backwards compatible with the 6L6GC in most modern amp circuits as they have far lower maximum ratings than the GC does (this is also true for the metal 6L6, small-coke-bottle 6L6GA and the straight sided 6L6GB - they have identical ratings to the 6L6G).
I had one of those coke bottle tubes break on me when I tried to pull it not knowing that the pins and plate had corroded together. It broke away from the base leaving the internals in place still in the socket. More than just a bad bond.
@LeviMan2001 Metal 6L6 have far lower max ratings than the 6L6GC - you risk killing the tubes and your amp if you use them in an amp running a B+ higher than 350V.
@MovieTech Hmmm well it's running 406v through a 470 ohm anode resistor. I got 'em and they work (although I had to bias them) and sound pretty dang good!
I used to run Sylvanias in my 5150, and they are nice. Supposedly, that's what Eddie's prototypes had. The only thing better is RCA blackplates, and that's what I use now. FWIW, Eddie has JJs in his new Fender amps, and Peavey is putting them in their new amps.
The 300B cannot be used as a sub for the 6L6. My personal favorite power tube is the 350B but, as mentioned below, check with your amp tech or dealer to be sure your amp can use these in place of a 6L6 of any type.
"...350B... plug and play replaceable for 6L6GC types..."
HEY... not so fast! 350B draws significantly more filament current than the 6L6GC (1.6 vs. 0.9a) and has lower max. plate voltage (360 vs 500v). I wouldn't call that plug and play. It would be a shame if someone were to destroy some lovely 350Bs (or a power transformer) by putting them in the wrong amp.
Yes, my bad there. For most applications in my experience the 350B has worked in place of 6L6GC tubes. I should have mentioned ALWAYS check with your dealer, tube technician, or manufacturer before you substitute power tubes, to make sure ANY substitue you wish to make (including the 350B) is acceptable and will not damage the amp or the tubes.
@lagus76 that is exactly what they are. The other give-away of a RCA-manufactured tube (regardless of brand) is the type number will be printed in a thick font within a similarly thick octagon, and the 'USA' is sometimes printed at the top of the octagon, and sometimes a dashed line will be below the octagon. the key is the thick dark gray ink that was used to print the type number on the tube - other manufaturers used the octagon but with a different font and thinner lines in the octagon...
I'm looking at re-tubing my Bugera 333xl with Electro Harmonix 6l6GC's and I'm given a choice of hard, medium, or soft. Can you tell me what the difference is?
The terms refer to the "breakup" of the tube, or where it begins distorting. Soft is early breakup. medium is normal, and hard does not break up until the amp is playing VERY loud.
@audiotubes I play a lot of high gain rock and metal. What would you suggest? I don't want my clean to breakup hardly at all, but i want some good saturation on my lead channel.
The blue glow is fairly normal especially with vintage tubes used with high plate voltages. It is what little gas is in the tube being ionized by the high voltage. It does not harm the tube or your sound.
sir i have five 6L6GC tubes all RCA made in usa but they are larger than the tubes you show in your great video and they have a red RCA logo in the glass, the logo that ends with a lightning shape
If the blue glow is being caused by gas, especially if it appears between the plate and cathode, then that tube is no good. The harmless sky-blue glow is caused by cobalt contamination. RCA types seem to produce this quite frequently.
Thanks so much. I own four vintage amps, three of which are older than I am (I was born in 1947) and many of the tubes in these amps are tubes I bought from you. Your web site and your videos are a great education for me. Keep up the good work. By the way, I also have a few of your very cool tee shirts. Looking forward to your 12AX7 videos. How about 5Y3? Maybe something giving us ignorant folks a brief idiot's guide to tube amp circuitry would be nice (in your copious spare time, of course).
Hi, The getter is an element that is "burned" inside the tube after it is sealed at the factory. This removes the last traces of air in the tube and deposits a metallic patch on the inside glass. This patch helps remove gas that may seep in over the years by oxidizing.
Thanks for your comments. I am working on getting more shirts available, and will be doing more videos. No time to sit and get bored, that is for sure.
Hi, Those are great vintage tubes. The brown getter does indicate wear, but many in this condition still test good. As long as it tests OK on a gas test it will still operate fine if proper bias is set.
The GE tubes tended to be gassy, handle less power and shorter lived. The Tung-Sol were pretty robust, as were the RCA branded 6L6's.
basspig 1 month ago
I don't think a KT66 will directly replace a 6L6GC. Also, those Russian 6L6GC wont work in some circuits designed for USA 6L6GC's.
2468xx 9 months ago
just to comply - russian 6l6's are not that bad. They just have different parameters
and can't run well on high voltages.
djglukbh1 1 year ago
Love this! good info! Thanks.... Wary of the 350B!
poikaa3 1 year ago
RCA grey plates 4 me thanks.
dancingrizz 1 year ago
Do all guitar amplifiers that use the 6L6GC tube sound the same all things being equal? After all, an electric circuit only regulates voltage from a wall outlet does it not....
mayito714 1 year ago
i don't know why i find this things REALLY COOL. my grand father had a factory of this things (i never got to meet my grand father though)
rikisaltacorp 1 year ago
What are your views regarding the RCA 6L6G grey glass coke bottles? Do they have any collectible value at all?
laterallateral 1 year ago
@laterallateral They may have some value to vintage radio and audio collectors. NOTE: The 6L6G is NOT backwards compatible with the 6L6GC in most modern amp circuits as they have far lower maximum ratings than the GC does (this is also true for the metal 6L6, small-coke-bottle 6L6GA and the straight sided 6L6GB - they have identical ratings to the 6L6G).
MovieTech 1 year ago
I had one of those coke bottle tubes break on me when I tried to pull it not knowing that the pins and plate had corroded together. It broke away from the base leaving the internals in place still in the socket. More than just a bad bond.
oc5nsli341nforce4 1 year ago
How do the Metal cased 6L6 tubes sound? I'm looking at getting some for a guitar amp.
LeviMan2001 1 year ago
@LeviMan2001 Metal 6L6 have far lower max ratings than the 6L6GC - you risk killing the tubes and your amp if you use them in an amp running a B+ higher than 350V.
MovieTech 1 year ago
@MovieTech Hmmm well it's running 406v through a 470 ohm anode resistor. I got 'em and they work (although I had to bias them) and sound pretty dang good!
LeviMan2001 1 year ago
i have the NOS Sylvania 6L6's in my peavey 5150 and boy, it screaamss now!
Mr5150II 1 year ago
@Mr5150II
I used to run Sylvanias in my 5150, and they are nice. Supposedly, that's what Eddie's prototypes had. The only thing better is RCA blackplates, and that's what I use now. FWIW, Eddie has JJs in his new Fender amps, and Peavey is putting them in their new amps.
cpc24 1 year ago
Can you replace a 6l6 with a 300b? What are the best power tubes you would recommend even if it can or can't replace 6l6?
kijifled2 2 years ago
The 300B cannot be used as a sub for the 6L6. My personal favorite power tube is the 350B but, as mentioned below, check with your amp tech or dealer to be sure your amp can use these in place of a 6L6 of any type.
audiotubes 2 years ago
"...350B... plug and play replaceable for 6L6GC types..."
HEY... not so fast! 350B draws significantly more filament current than the 6L6GC (1.6 vs. 0.9a) and has lower max. plate voltage (360 vs 500v). I wouldn't call that plug and play. It would be a shame if someone were to destroy some lovely 350Bs (or a power transformer) by putting them in the wrong amp.
1ultrasonic 2 years ago
Yes, my bad there. For most applications in my experience the 350B has worked in place of 6L6GC tubes. I should have mentioned ALWAYS check with your dealer, tube technician, or manufacturer before you substitute power tubes, to make sure ANY substitue you wish to make (including the 350B) is acceptable and will not damage the amp or the tubes.
audiotubes 2 years ago
I have four 6L6 GC tubes in my Fender Bassman 100 that says "Made by RCA for Fender" They look like Blackplates. Do you know anything about that?
lagus76 2 years ago
Fender used RCA tubes for many years. If your amp and set of tubes dates from the 1960s they are probably real RCA made blackplates.
audiotubes 2 years ago
@lagus76 that is exactly what they are. The other give-away of a RCA-manufactured tube (regardless of brand) is the type number will be printed in a thick font within a similarly thick octagon, and the 'USA' is sometimes printed at the top of the octagon, and sometimes a dashed line will be below the octagon. the key is the thick dark gray ink that was used to print the type number on the tube - other manufaturers used the octagon but with a different font and thinner lines in the octagon...
MovieTech 1 year ago
I'm looking at re-tubing my Bugera 333xl with Electro Harmonix 6l6GC's and I'm given a choice of hard, medium, or soft. Can you tell me what the difference is?
servantguitar 2 years ago
The terms refer to the "breakup" of the tube, or where it begins distorting. Soft is early breakup. medium is normal, and hard does not break up until the amp is playing VERY loud.
audiotubes 2 years ago
Fantastic, thanks for the info! :)
servantguitar 2 years ago
@audiotubes I play a lot of high gain rock and metal. What would you suggest? I don't want my clean to breakup hardly at all, but i want some good saturation on my lead channel.
servantguitar 1 year ago
The 6L6 GC tubes in my mesa boogie amp glow a pretty blue on the inside of the galss.
mesa401 2 years ago
The blue glow is fairly normal especially with vintage tubes used with high plate voltages. It is what little gas is in the tube being ionized by the high voltage. It does not harm the tube or your sound.
audiotubes 2 years ago
sir i have five 6L6GC tubes all RCA made in usa but they are larger than the tubes you show in your great video and they have a red RCA logo in the glass, the logo that ends with a lightning shape
what kind of 6L6 tube are ??
and what would be the price for sell them?
thanks
faunoram 2 years ago
If the blue glow is being caused by gas, especially if it appears between the plate and cathode, then that tube is no good. The harmless sky-blue glow is caused by cobalt contamination. RCA types seem to produce this quite frequently.
LordKelvin100 2 years ago
Thanks so much. I own four vintage amps, three of which are older than I am (I was born in 1947) and many of the tubes in these amps are tubes I bought from you. Your web site and your videos are a great education for me. Keep up the good work. By the way, I also have a few of your very cool tee shirts. Looking forward to your 12AX7 videos. How about 5Y3? Maybe something giving us ignorant folks a brief idiot's guide to tube amp circuitry would be nice (in your copious spare time, of course).
acatasus 2 years ago
Check out the 6550 / KT88 video. It could be done in 1 part. The 12AX7 video will probably have to be a 3 or 4 part series! Thanks for watching.
audiotubes 2 years ago
What is a "getter"?
50unitedstates 2 years ago
Hi, The getter is an element that is "burned" inside the tube after it is sealed at the factory. This removes the last traces of air in the tube and deposits a metallic patch on the inside glass. This patch helps remove gas that may seep in over the years by oxidizing.
audiotubes 2 years ago
Thanks for your comments. I am working on getting more shirts available, and will be doing more videos. No time to sit and get bored, that is for sure.
audiotubes 2 years ago
Comment removed
acatasus 2 years ago
Hi, Those are great vintage tubes. The brown getter does indicate wear, but many in this condition still test good. As long as it tests OK on a gas test it will still operate fine if proper bias is set.
audiotubes 2 years ago
Thank you! :)
ininper 3 years ago
Great vid....any way one can be done for 12AX7's?
ryanmichael95 3 years ago
I will probably have to make 2 or 3 videos to cover the 12AX7 tubes. Stay tuned!
audiotubes 3 years ago