6L6--- which brand best keeps the fenders sound

[popoahi]

one of my 6L6 is microphoning when tapping cabinet right above the tubes or when I tap it lightly when amp is on, reverbs on 9..it also has a different sounds when tapping all four tubes with a screwdriver...you can easily tell which tube it is..
I take that to be a sign that the one tube is going bad??? sounds like the tube is broadcasting a reverb sound like a mic is on it..
also developing a kinda strong hummmmm especially annoying when playing at high volume 6 and up...can I also attribute that to the 6L6 tubes going bad especially that one tube that's microphoning???

I'd like to stay close to the original sounds of my twin reverb so are JJ 6L6 tubes a good choice??? the store has only a set of JJ 6L6's for $85.

and when biasing them I put the meter on the no#3 pin right???

aloha, popoahi

[km6xz]

If you want the sound to change the least, note the brand and model of the current tubes and look for a little sticker on the base that has a letter or number code and replace the old tubes with the same brand, model an relative gain code. In fact, if those 3 items are known, just replace the microphonic tube. Leave the bias where it is now if you get a tube with the same characteristics.

[popoahi]

I always thought you have to change all 4 as a set???

the tubes I have are Macintosh so I doubt I can find anymore of them...he only ones I found are JJ's AT $85.00 a set...... never used or heard this brand have you???

I've got a loud hum so I'll buy 4 and maybe just try changing that one microphonic tube first but if the humm is still there I may have to change more than just the 6L6's?? 2-12ax7, 2-at7, and a 7025.....

thanks for the help....
popoahi

popoahi

[km6xz]

If the hum is 120 hz one tube being dead could unbalance the output so the normally cancelled supply ripple would be heard. It also might mean a shorted tube.
MacIntosh had RCA and GE rebrands at various times back in the day but anything now with the MacIntosh logo is Russian from New Sensor.
JJ's are liked by some hated by others because they are very spotty on reliability. Some dealers must be getting the secret patch because they say they are reliable but my experience here is just the opposite. Their common failure mode is microphonics in their power tubes that make them gradually unusable even if generating full power. One amp maker here, Yerasov, uses JJ and every JJ Yerasov amp I see, often just shipped from the factory, has at least one bad power tube and usually all are bad. The ones that are not shorting are so microphonic that the amp is unusable. Microphonics are not usually covered by tube manufacturers.
In a head they can last longer but in a combo, they are too risky.

[popoahi]

so can I buy the tubes from you?? I'm in honolulu so thats not a problem right...
I'd like to get what you're using... you say you're buying chinese tubes in2k lots?
so I assuming they're for sale??
or if you can't sell to me where can I go to order my 6L6 set,,, I could only find one set of JJ's here today...
I'd really like to change all the tubes and am considering changing to new speakers to.. at high volumes (9) on both volume knobs when hitting the 5,6 strings they can sound "flubbery" or soft...
this amp tech who looked at my twin said the bad tubes could contribute to the speakers sounding soft but if not I'd like to buy as close too original speakers
as possible to preserve the original fender sound..I've checked out the "swampthang" and similar speakers but I think it would change the sound to much...
I have not ever seen the type of speakers that came on my TW-BF...so I need to find something else that's as close as possible...

but first things first , can you sell me a set of 6L6's?

aloha, popoahi

[km6xz]

Exporting to the US would be pretty expensive in shipping, I would go to a local dealer who warranties them. No one has ever asked before so I am not sure how much it would be, surely more than the tubes themselves however.

[ron vogel]

Fenders typically use either GE or RCA 6L6's...but safer to go with short bottle GE's. (I am assuming you have a more vintage Fender)

Just do a google search for a matched Quad GE 6L6...it's going to be pricey, but it's what was generally in there from the factory up until the 70's. Stay away from green label JAN's...those were late 70's to early 80's tubes that are very harsh sounding.

If you have a fairly recent amp, then just get some JJ's and call it a day.

[km6xz]

.... green label JAN's...those were late 70's to early 80's tubes that are very harsh sounding.

Really? What in a tube is "very harsh sounding" other than when you drop one on the concrete floor?

[big_teee]

I like the short and tall bottle 6L6 TADs.
They are chinese tubes, but TAD does a good job of screening them.
Never bought a bad TAD tube, but not bought a huge amount of them.
I think Enzo likes Ruby, about the same deal as TAD.
I've had nothing but bad luck with JJs.
T
** The Tube on the Concrete does have a distinct harsh Sound.
I Dropped a Prize KT77 on the shop concrete floor, and it literally exploded!

[ron vogel]

Really? What in a tube is "very harsh sounding" other than when you drop one on the concrete floor?

Well, to be honest...I haven't tried the green label power tubes...only the 12AX7's. The green JAN's are super harsh, people ask premium for them on Fleabay because their JAN's, but they are just the last of US manufactured tubes when quality was not as good. By harsh I mean excess of 2KZ to 4Khz range. Maybe I'm a snob...whatever, but I prefer to buy tubes from the Late 50's / Early 60's era when quality was the best.

[km6xz]

Tubes do deteriorate with long storage, there is out-gassing that changes the characteristics. They were well made and pretty consistent compared to today but they are not the same tube they were when put into the box and stored for 60 years.

Tubes have very little impact on frequency response or spectrum so there is something else going on to be generating more energy in that band. Any tube is pretty flat to 60Mhz so a change in tone will be due to shift in operating point compared to another tube of different assembly in a given amp. When overdriving a tube that creates the distortion of harmonics and inter-modulation we call "tone" but drive a tube in a slightly different way like into the compression knee on two different triodes, they are going to perform very much alike. What people confuse with a better tone from one tube versus another is usually sensitivity when leaving all the gain settings the same and just swapping tube. If instead they made the minor adjustments in drive to get both tubes just into compression, they will sound very similar. We had a player "test" EL34 vs 6L6 and left the settings fixed which is not going to say anything about how the tubes compare unless you have no controls or they are locked in place. Faulting testing or testing without controlling variables is probably the main reason for some people stating brand X is great and brand y is junk, when setting either optimally would remove most of the perceived difference in sound.
The best tubes for sound are those which work all night in a key gig and do not blow up at the beginning of the second set. Audiences are not partial to performers playing air guitar silently for the remainder of the show....

[popoahi]

thanks ron

my twin blackface is either a 80's or 70's no one been able to nail it down and I hven't yet sent in pic's to the site..when my boy teaches me how to then i will..
I hear that JJ's R good and bad so ??? I will look for GE's but it may be hard I wud think??
thanks again, popoahi

[Justin Thomas]

popoahi,

your Twin is an early 80s 135W. 99% for sure. I looked at your other thread. If it has a black faceplate AND a Master Volume, it has to be, basically. It's electrically the same as any late 70s/early 80s Twin Reverb, well, as close as Fenders can be. They were always in transition... Starting around 1980 til about 1982, the faceplates could be ordered black OR silver, it was an option. But they are the same amp. If the "Twin Reverb" name is horizontal and not slanted, it's 80s. Also, I'll bet your "Fender" logo on the front has"Made In USA" in tiny letters underneath? Either way, blackface AND Master Volume mean 80s.

The really important part is NOT to judge it as "crap" just because books & the internet tell you to. Your ears do that.

Justin

[ron vogel]

Tubes do deteriorate with long storage, there is out-gassing that changes the characteristics. They were well made and pretty consistent compared to today but they are not the same tube they were when put into the box and stored for 60 years.

Tubes have very little impact on frequency response or spectrum so there is something else going on to be generating more energy in that band. Any tube is pretty flat to 60Mhz so a change in tone will be due to shift in operating point compared to another tube of different assembly in a given amp. When overdriving a tube that creates the distortion of harmonics and inter-modulation we call "tone" but drive a tube in a slightly different way like into the compression knee on two different triodes, they are going to perform very much alike. What people confuse with a better tone from one tube versus another is usually sensitivity when leaving all the gain settings the same and just swapping tube. If instead they made the minor adjustments in drive to get both tubes just into compression, they will sound very similar. We had a player "test" EL34 vs 6L6 and left the settings fixed which is not going to say anything about how the tubes compare unless you have no controls or they are locked in place. Faulting testing or testing without controlling variables is probably the main reason for some people stating brand X is great and brand y is junk, when setting either optimally would remove most of the perceived difference in sound.
The best tubes for sound are those which work all night in a key gig and do not blow up at the beginning of the second set. Audiences are not partial to performers playing air guitar silently for the remainder of the show....

I will say this first, I read through the forum and see your replies often. I respect your knowledge and opinion...however, I have lots of tubes...like hundreds at this point. In every amp I've rolled tubes to get the tone I'm after...after other things were already addressed. I am most familiar with 6V6 characteristics. Some brands tube to tube are more subtle, some not. I am also only recording, and do hear a bit more on playback than what you would hear in a band setting. In a band setting, you really wouldn't hear much of a difference. Speakers will definitely impart the most color to the sound, but when your a geek musician like me, you are always looking for more tonal options. Tube for tube, I like the older ones...however New production tubes sound great in an amp optimised to use them.

[überfuzz]

First of all. I'm not sure you should bias your tubes if you don't know what you're doing. You might shorten the life span on them if you give them to much juice. If you like to bias them yourself you'll find loads of tutorials and such on internet. Probably some good clips on youtube as well.

About the tone. If you really want to effect the tone of your amp you should try different guitars, then speakers. Did you know that John Entwistle changed strings on his bass before sound check, before gig..? Well, in your pursuit of the perfect tone, somewhere down the road you'll find the tubes... But try to get that one in a life time guitar and good speakers first. :-)