which tubes for tone

[andy dawson]

hi
what are the best tubes for pre and power stage for mts?
I got tweed, top boost and xtc.
When i first bought the rm100 it sounded amazing but it's lost some of it's sparkle. I;m looking for tone over gain. i play hard rock, not metal

cheers from UK!
andy 8)
2 x les paul standard
paulman tele
paulman custom
fender strat
78 gibson v

 

[Julia]

New Production:

* Tung Sol 12AX7
* Believe it or not I've put a JJ ECC83S back in V1 -- this is a bright amp.
* XTC -- don't know this mod but you might try one TS and one Chinese, and if it's too fizzy replace the Chinese with a JJ.
* Tweed -- I run my JTM (very similar) with two JJs.
* Top Boost

NOS: if you're rich

* you can't beat a Mullard.
* for the Tweed -- you can't beat a Telefunken

For the PI: some JAN 5751. Philips seems to be the favorite here.

Power tubes: Ruby =C='s accept no substitute. I'm running Ruby 6550C's and bias these around 40 mV. Massive headroom with a soft breakup.

 

[crankyrayhanky]

many of these pre tubes JJ, ElectroHarm, TungSol...I don't know if my ears are fried, but I don't hear a huge difference when swapping them around. I'd rather spend the $ on a a promod that has any of these tubes then have a stock mod filled with all of these tube choices that aren't that big of a difference.

Keep in mind, not every JJ will sound alike, so while one person says they love it and another says no way, it is all independently variable imo.

That being said, I'm going to get chinese pre tubes because the RigTalk Eggy guys say it rules in Marshally mods

 

[Mike P]

The mods will certainly make a much bigger impact in sound and tone, but for my money, nothing beats the Tung Sol 12ax7's and Mullard power tubes.

I'm not a fan of JJ's in the preamp or power amp. The mids are just too crammed up for my taste.

 

[Julia]

Basically what I've found is that the preamp tubes really aren't going to change the character of the amp. I had a supposed quiet Ruby 12AX7AC5 HG+ that was highly recommended for V1 in V1, but I noticed the tube was hissyer (if that's a word) than the JJ. Yes it got more gain out, but then see my signature. So back in went the JJ -- darker tube, and a bit quieter.

The 5751 got rid of a lot of noise in the amp when I stuck it in the PI but it didn't change the tone of the amp.

And honestly, since I figure tops I'm pushing 10W out of this thing, maybe 15W, which through a 412 is mighty loud to use without hearing protection (and if I've got to stick stuff in my ears just to use more power, unless the venue calls for it, what's the point). I found that there really is very little difference between the tone regarding power tubes unless you push them into distortion and god help your neighbors. So basically my power amp runs clean. If I need that power amp breakup sound, there's always the Keeley Java Boost -- granted it's a germanium transistor, but hey it does the job and people seem to like the tone with the Marshally stuff.

 

[andy dawson]

thanks guys.
i might by a selection of preamp tubes and just swap and change to see what results i get. I can get tungsol in uk no probs.
As i said , when the amp arrived with stock tubes it sounded amazing but it's lost some of it's sweetness and response, particularly the nice kind of feedback
I have sent gigmods a jtm for modding. I'll be interested to see what that sounds like and whether any of the tubes are changed.

 

[Julia]

Another thing to check is the bias on your power tubes. They may have crept up a bit, or dropped. Bring them back into the middle of the range and you should be fine.

BTW, the stock Marshall EL34s are S.E.D. =C=. Marshall just relabels them. They're about the best sounding EL34 I've heard.

 

[himudc]

Tubes..........Well Andy lets back it up a minute here. When Randall voices these MTS Amps (particularly the modules), they are designed to emulate particular amps using the tubes supplied by Randall's bulk supplier. (My preamp tubes are EH and the power tubes (used to be JJ E34L). The phase inverter tube is the most important tube in the pre-amp section. The stock PI tube is neither cold nor warm it is sort of neutral. This makes things easier for Randall to maintain some consistancy. If you want to make your overall sound more detailed and dimensional, think about an NOS 12AX7 from one of the European companies. (Siemens is a good one or a Mullard). If you want to warm things up, nice round, bluesy sound, think about an American 12AX7 (RCA Blackplate or Greyplate, GE, or Raytheon).

Personally I left the preamp tubes alone in mine and swapped a little bit in the power section. I left the stock JJE34Ls in the middle slots and put NOS Siemens EL34s (circa 1970) on the outside. The Siemens tubes have a much more detailed sound than the JJE34L and have a really cool overdrive about them. Combined with the low end punch of JJE34L, my amp can seriously roar. I have all the tubes biased at 38mV. According to the Randall owners manual this is right at the limit for the EL34s but NOS tubes are typically of much higher quality than what is produced today and will put up with far more abuse than the tubes of today.

This little swap in the power section made the modules sound much more like or even better than amps they were designed to emulate. Sound is highly subjective and opinions are opinions. We all have them. Whatever tube swap makes you happy is the correct swap. Just remember, tubes are like tires, and you get what you pay for. Just a few things to think about. Let me know what you end up doing and how it turns out.

 

[andy dawson]

That's really useful advice
thanks a lot.
I'll let you know how i get on

andy

 

[speedemon]

My $.02,

I have had the Randall about a month, it was all JJs and every time I replace a JJ 12ax7 it gets better. But then I didnt' like the JJ in my other amps either. I put a 5751 in the PI and a Mullard reissue in V1, the George Lynch clean module went from "crap" to "useable", and the overall tone improved to my ears. I put a Tung Sol I had into the XTC, and it helped some, but still a little muddy.

I didn't expect the amp to be so sensitive to preamp tubes. I too have found that for under $15, you don't get significant variance from 12ax7s. My favorite "cheap" 12ax7 was the Sovtek.

I concur that different tubes are going to perform differently with diff modules, and the tube should suit the sound you are going for.

Good luck!

 

[Nightdare]

Sovteks sound a little lifeless
JJ's are a bit mellow with some added mids
The Ruby 12ax7's that came in one of my modules are similar to the JJ's but seem to have a bit more clarity
Electro Harmonics are the most 'even response''
Tung Sol add some high mid grind - my preferred choice
Chinese take that a step further, but are a bit 'glassy'

...This all ofcourse to my ears,