favourite preamp/power tubes for a jtm style marshall?

Chickenwings

Alnico 6/8
I have this amp based on a jtm, but it has a master volume and stuff.
It can run kt66, el34, 6l6 and 6ca7s with the correct biasing.
Right now it has chinese el 34s (they came stock in it), but i reckon it is ready for a retube.
Considering tung sol el34s...but i've not made up my mind yet. I could be convinced to go for any of the different tube types and any brand.
What i am after is sweet, even harmonics more than anything else.
Throw in your vote for fave preamp tubes too. It has jjs right now, but generally i like EH in marshalls, however, i am open to suggestions.

(yes i would like those 78 pickups ;) )
 
Re: favourite preamp/power tubes for a jtm style marshall?

Of new stock...

JJ KT77 - sounds like my original Tesla EL-34s sounded in my Marshall
EH 6CA7 - great cleans and beautiful distortion, have these in my Orange right now
Golden Dragon KT66 (ValveArt's version of this is surprisingly good, even though inexpensive - almost appears to have been made on the same GEC tooling)

for preamp (particularly V1), I would get
TAD 12AX7A-C Selected - sounds just like my Mullard 10M
JJ ECC803A S - sounds very close to the Mullard also - large plate though, supposedly can be microphonic
GrooveTubes GT 12AX7A-C
Ruby 12AX7AC5
 
Re: favourite preamp/power tubes for a jtm style marshall?

Generally speaking, NOS is your best bet.

For pre's (12AX7 and the like) Mullards of course, but sometimes you can get deals on Mullards with
other manufacturer's (GE, Valvo, etc) labels on them (there's a factory code system to determine).

And don't forget the mil-spec versions (CV4004) of the 12AX7.

I don't know what the market is like nowadays; IIRC back in 2003 I paid around $60 per.
I've had the same Mullards in my Marshall since then and have had zero issues.

I've got a pile of new manufactured 12AX7s (3 each of brand) I bought over 10 years ago just collecting dust. I did a tone test
with all of them. None of them got better marks than "meh". JJ, Sovtek, EH, EI Gold etc... the Sovtek 12AX7WAs were
by far the worst; buzzy top end and mushy midrange.

For new manufactured EL34 style, I've tried two:

Tung Sol EL34s - they're "okay"; kinda mushy
EH 6CA7s - they're great; big and clear. highly recommended
 
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Re: favourite preamp/power tubes for a jtm style marshall?

thanks guys. I have used EH6ca7s before in a musicman. They were pretty great. Lots of headroom.

I'm looking for new, production tubes tho, not nos. I cant be bothered looking up serial numbers and prices of nos gear. I just want something that works well, and that i can replace without having to go searching for a holy grail.

I guess atm its looking like EH in the front and eh6ca7 in the power section unless someone else chimes in with a glowing recommendation for other stuff?
 
Re: favourite preamp/power tubes for a jtm style marshall?

I would try some JJ's. The 6CA7's for the power tubes and I would recommend you try the medium gain ECC83's You'll still get plenty of crunch but a bit more headroom.
 
Re: favourite preamp/power tubes for a jtm style marshall?

I've liked The Tung-Sol EL34Bs and their 5881s in my MkV and JCM900 respectively. I tried their 6L6GCs in the MkV and they were ok, but sound great in my Fender HRDX. I've also had great results with their ECC803/12AX7 in both the MkV and to a lesser degree the JCM. I had EHX 12AX7s and EL34S in an amp a few years ago and found them to be too stiff and buzzy, but I've never had a chance to try the 6CA7s
 
Re: favourite preamp/power tubes for a jtm style marshall?

Yellow Label Mullard ECC83-hard to find but amazing (actually probably easier to find elsewhere-rare in the USA). No comparison to the stuff tube manufacturers are making today.

Old JAN/GE5751s are nice too. And not terribly expensive. They will reduce some gain.


I am not well versed in N/OS EL34s, so I would hesitate to make a recco there,

Best site I have found for info is Audio Tubes

EDIT- saw your other post- so..Nevermind.
 
Re: favourite preamp/power tubes for a jtm style marshall?

i love kt66 tubes in those circuits but its a pretty different tone. big bold deep tight bottom, creamy mids and open clear top end that isnt overly sharp. doesnt have the upper mid crunch of el34's though.
 
Re: favourite preamp/power tubes for a jtm style marshall?

i love kt66 tubes in those circuits but its a pretty different tone. big bold deep tight bottom, creamy mids and open clear top end that isnt overly sharp. doesnt have the upper mid crunch of el34's though.

To me i think it suits JTM45's better than EL34's do. For that matter i prefer 5881's in JTM45's over EL34's. EL34's are great in 1987's o r 1959's. But for JTM45's the 66s are where its at.
 
Re: favourite preamp/power tubes for a jtm style marshall?

i agree. el34 in a super lead is perfect and is the classic marshall plexi tone. but the jtm is a different beast and is so glorious with the 66's
 
Re: favourite preamp/power tubes for a jtm style marshall?

the descriptions of 66s sound like the kind of tones i like. Thanks fellas.
Gold Lions or Jjs?
 
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Re: favourite preamp/power tubes for a jtm style marshall?

golden lions or shuguang. skip the jj. the shuguang are good tubes but they need to be biased a little hot or they can sound thin. in general i find kt66's sound best biased a little hot but the shuguang need to be biased that way to sound good
 
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