MARSHALL 2144 JMP Master Volume HELP WITH TUBES...

[slowcoach]

I own this lovely amp and have done for a while...

http://www.drtube.com/schematics/marshall/2144-pic.jpg

Ive gigged it to death and it has probably never had a change of tubes since 77'

It hisses, crackles and pops...

frankly im scared.

would anyone be able to tell me what the cheapest and best option for a tube exchange on it would be??


Cheers

[Lonely Raven]

I own this lovely amp and have done for a while...

http://www.drtube.com/schematics/marshall/2144-pic.jpg

Ive gigged it to death and it has probably never had a change of tubes since 77'

It hisses, crackles and pops...

frankly im scared.

would anyone be able to tell me what the cheapest and best option for a tube exchange on it would be??


Cheers

It probably needs more than just tubes. You need a proper "service", which is replacing the electrolytic caps, replacing tubes, and biasing the amp. Plus any cleanup and replacement if there happens to be anything burnt up or out of spec from running the amp without service all these years.

[slowcoach]

Is it going to break my bank??

[NickC]

Is it going to break my bank??

That's hard to tell without additional information.

Can you post a high resolution photo of your latest account statement?

[David Root]

Maybe $300.00 if it only needs a cap job, a clean up and you can tolerate current production tubes (which I doubt, after playing the real thing for so long). If the original tubes are still OK, maybe $200.00.

If all the original tubes are dead/dying and you need the same tone as the Mullards it likely came with new in '77, look out. NOS, three I63 Mullard 12AX7 and a pair of Xf4 EL34 will cost you about $550.00. If the 12AX7s are still OK, which they could be, then $225 for the EL34s, NOS.

[slowcoach]

no worrys... i will post out my bank details too...


Has anyone got any recommendations on tubes at all?

[slowcoach]

Ace thanks a lot.

Time to get a proper job then.

RAD.

[David Root]

Like I said above, three short plate Mullard 12AX7 with I63 type codes, and date code like B5F2, for example. B is for Blackburn, England, the best factory for guitar amps, 5 is 1965, F is the month, 2 is the week of the month it was made.

EL34s are similar, type code is Xf4, date code B6D4, for example, would be 1976. The earlier Xf2 is better but costs even more.

Don't buy any '80s Mullards, they don't sound the same, and don't buy any with R instead of B on them. R is the Mitcham factory, they sound different from the Blackburn ones, more linear, less exciting tone, more hi-fi.

Pull out the existing tubes and read these codes, they are etched in the glass down near the base. The type code is above the mfr/date code.

I can recommend HiTest Guitars, Gregg Levy, www.hitestguitars.com. He ain't cheap but he has the real goods, NOS in original boxes, not like the E_Bay stuff, "tests NOS, in white box". I have bought a lot of tubes from him.

[thejaf]

Tube recommendations are always personal, and everyone has favorites, pet peeves, and those we love to hate. I haven't had to purchase a whole lot of new tubes in the last 10 years, but of those I have my favorite 6L6 has been JJ, and my favorite EL34 to date has been the Ruby EL34B-STR.

As for preamp tubes, just experiment to you heart's content. I've been wanting to try the new Tung Sol 12AX7, but I honestly just keep forgetting (tube swapping isn't as important to me so much anymore, and I still have dozens of USA and Mullard pulls on hand).

Lastly, I can't say enough about squirting $0.43 worth of tuner cleaner/lubricant into all the pots, input/speaker jacks, and tube sockets.

[NickC]

no worrys... i will post out my bank details too...


Has anyone got any recommendations on tubes at all?

I was just kidding with you.

Many folks around here know NOS tubes in amazing detail. While I'm not one of them, I respect that knowledge base. Sadly I must eschew all that NOS goodness, lacking the will and resources to keep all my amps dressed in the finest glass. I use current production tubes almost exclusively (apart from some still functioning ancient preamp tubes). I like JJs because I can afford them and they get the job done reliably. I play bar gigs, the occasional summer festival, and similar. The acoustics in the typical bar are not worthy of amps sporting expensive NOS tubes. Nor is it "safe" to drag out vintage (i.e valuable) gear to such venues. Nor will the audience notice or appreciate it.

Don't get me wrong, I'm not knocking NOS tubes ...... just presenting my take on the current state-of-play for a typical gigging guitar-slinger based strictly on cost/benefit ratio.

[slowcoach]

Ive been poking around... cleaning it etc

turned it back on...

ONE MASSIVE pop and a really BAD burning smell...

A service is needed.

Had a look at the tubes... and there is no lettering on them at all.

bizzare

any way CHEERS for all your time and effort!

thanks!

[thejaf]

Unplug it and don't turn it on again. Take it to get serviced.