OK tube freaks, I throw down the gauntlet!!!

Ok guys if you know loads about tube types here's a question for you.

I have a big box of various assorted tubes, some Mullards (yes!!!) and Philips etc.

I think the vast majority of them are old radio tubes (although some of these tubes are actually new).

I'll list the tube numbers and if any are suitable to be used in a guitar amp, can you let me know?

This is more of a finger-crossing exercise than anything really!!!

Any tubes that I can't read the number if it's worn off I've indicated with a '?'


Mullard ID5GP
Super Radiotron 6DQ6A
Mullard 5CM5
Philips Miniwatt 6CM5
Philips Miniwatt 6BZB
Mullard 6BL8
Mullard 12A3?
Philips 6BZ6
Philips Miniwatt 6EH7
Mullard 6CA4
12AU?
Super Radiotron 6HS8
Super Radiotron 6AV6
6EA6
Brimar EF80 (brand new with red caps over the prongs at the bottom of the tube!!!)
Super Radiotron 6KV8
Mullard 6N8
Philips Miniwatt 6BM8
Philips Miniwatt 6BX6
Philips Miniwatt 6B17
Mullard 6BL8
Mullard 6BX6
Mullard 6BQ5
Mullard 6BY7

That's pretty much it. As I said, I think most if not all are radio tubes, but no biggie. Bought the whole box, around 60 tubes, for AUD$10 at a flea market out of interest. And considering about 1/2 the tubes were in Mullard boxes, I took the chance!

Replys appreciated.

Thanks

The only one I see that is useful is the 6BQ5 / EL84.

Thanks Boogiebabies

Assuming I have 2 and if (big if) I could verifiy they were close enough to use together, could I put them in an amp (my Marshall JTM 60 comes to mind)?

If so, what would be the difference to EL34s?

This is more curiousity than practical thinking really.

NO you cannot put EL84's where EL34's belong. Wrong size for one thing, different characteristics for another...

keithus77 said:

Thanks Boogiebabies

Assuming I have 2 and if (big if) I could verifiy they were close enough to use together, could I put them in an amp (my Marshall JTM 60 comes to mind)?

If so, what would be the difference to EL34s?

This is more curiousity than practical thinking really.

Click to expand...

Different pin-out, you would need to get some THD yellowjackets to do this.

I see. Would it be worth it? How would they sound?

keithus77 said:

I see. Would it be worth it? How would they sound?

Click to expand...

Hmm.. think Vox-like jangle. They have a very distinctive high end chime to them.

I'd not run them as a full power section if you like mega distortion/crunch, I use two in my dual rec along with two EL34's, great combo.

Hell, you could scrap together a simple amp around most of those tubes! Build yourself a little amp and experiment with some of those odd tubes...get data sheets and see what you need.

The Mullard 6CA4's are EL-34's. Hold on to those!

Wow, thanks Guitarzan

I didn't know 6CA4's were EL34s. I'll have to see if I have 2 or more. I know you need to have two that are fairly close for it to be optimal to use together, but could I (assuming I have 2) throw them both into an amp and try them out without any issues (ie my am blowing up!)?

How would the Mullard 6CA4s sound compared to Svetlana EL34s?

Also, what would Mullard 6CA4s be worth out of interest?

An EL 34 is a 6CA7. If he had Mullard EL34's or 6CA7's he would know it.
They would have date codes like XF2, XF3 and XF4 and would say EL 34 - Made in Great Britain.

Platypus said:

keithus77 said:

I see. Would it be worth it? How would they sound?

Click to expand...

Hmm.. think Vox-like jangle. They have a very distinctive high end chime to them.

I'd not run them as a full power section if you like mega distortion/crunch, I use two in my dual rec along with two EL34's, great combo.

Click to expand...

EL84s in yellow-jacket converters, stuck into a Marshall EL34 amp does not equate to a Vox amp. Not at all! Not all EL84 amps sound like a Vox, nor do they sound like each other. I would not recommend trying this with your amp, Keithus.

I would recommend testing your tubes, selling them to someone who can use them, then buying some nice tubes for your Marshsall.

- T

The 6ca4 is not an el34. 6ca4 tubes are pretty small and were used in old ampegs for a while. Yeah hold on to that one to use as trade stock or to sell towards something else.

The Mullard 6CA4's are EL-34's

Click to expand...

Oh ****... My Bad folks. I don't know what I was thinking. My apologies. I'll take that back.

I think that these tubes will not work, even what are this fucking mullard are them chinese????
Packed all and send it to my tube assylum by ups

I think that there are thousands of tube models, and it is so difficult to remember all the models.
That tubes that you mentioned aren´t the classical for guitar amps but....
if the features of that tubes are so close with the classical amps tubes you could replace them only doing a few mods on the circuit.
So the first step before you go to sleep today is check the duncan web type the tube model and see which are the equivalents, after these you must to download the datasheet, and then you could go to sleep.
For example last day I bought some general electrics tubes on an old electronic shop they were the pl84 and it costs to me less than 1 euro.
When I donwloaded the pl84 datasheet I saw that they are exactly the el84 with a less power and it were usen on class A or " single ended " topologys.
For example my 20/20 is the classical push-pull configuration, and if I want to replace my el84 with pl84 I need to modified from push-pull to class A.
Ummmmmmmmm it gives me an idea what about implement a class A, push pull topology switcheable like the lonestar, with my 20/20 working on 40 watts on push pull or 20 watts on class A????
Maybe I must go to sleep because I´m thinking too much for this night.

fatboy135 said:

When I donwloaded the pl84 datasheet I saw that they are exactly the el84 with a less power and it were usen on class A or " single ended " topologys.
For example my 20/20 is the classical push-pull configuration, and if I want to replace my el84 with pl84 I need to modified from push-pull to class A.
Ummmmmmmmm it gives me an idea what about implement a class A, push pull topology switcheable like the lonestar, with my 20/20 working on 40 watts on push pull or 20 watts on class A????
Maybe I must go to sleep because I´m thinking too much for this night.

Click to expand...

Oh my GAWD!!

I'm not trying to be insulting, but yes, please get some sleep before trying out your diabolical plan. You'll respect yourself more in the morning, and you won't end up ruining a perfectly good amp just because you got a deal on cheap tubes that won't work in it (not as you're planning). What were you thinking?? :roll:

- T

don´t be afraid TW that mod needs a few time for me, and I don´t have so much time.
Anyway there are some days I´m thinking about to put a new little circuit single ended, class A inside the 20/20 amp together the push pull circuit. It just be switcheable, so for example if I´m playing on a gig I could use the 20/20 push pull setup ( 40 watts ), and if I´m recording I could switch it into the one tube el84 class A ( 5 watts ), to record as cleaner as I can.. I don´t know if I´m explaining well, but there is quite similar to lone star idea.

I know all about single-ended amp architecture and sonic response. It is a lovely idea. It isn't going to happen with the 20/20, though, so just step away from the soldering iron and focus on your guitar playing :lol:

If you're really interested in the stereo single-ended EL84 amp idea, try the Lexicon Signature 284. That's what I use for that purpose, and it works very well - especially after a minor mod that allows you to use finer NOS power tubes. You can get these amps, used, for about $400 USD.

- T

**** dude you are fometing my G.A.S...
Jokes apart, it is so difficult that I keep me away from iron soldering, because I earn my life with it
I was seeing the lexicon, but... what hells is it???? it seems to be something like the recto preamp????

The Lexicon Signature 284 is a great little stereo recording amp that takes advantage of the power-tube clipping you can get at low-volume from each EL84. I've got one Amperex Bugle-Boy '50s EL84, and a '60s Mullard EL84 - taking advantage of their different tonal characters by mixing them with my different speakers (Weber Silver Bell for the Amperex, and Blue Dog for the Mullard). Read up on this amp - its very cool!

- T