My older MT15 has the factory installed RUBY 6L6GCMSTR (short bottle 6L6) power tubes. Since I've played the MT15 5-10 hours per week for 2.5 years, I'm planning to replace the power tubes soon. I love the sound of the Ruby tubes and clearly they have lasted well, but they are currently/no longer available. The think I like about my MT15 with Ruby's is that the sound stays pure on both the clean and lead channels, with the volume up to 7 or 8 (which is much higher than I normally go). I contacted a tube vendor who recommended the TAD 6L6GCM-STR REDBASE, which by all accounts is a superb tube for the money with the pure headroom characteristic that I like, but I'm concerned because it's not short bottle, and would only have about 1/4" clearance in the MT15 cage. The tube vendor recommended Sovtek for a short bottle replacement, but after listening to "shootouts" on YouTube, I'm not a fan of the Sovtek sound. Current MT15 amps have JJ 5881 installed at the factory. The JJ are lower cost and people on the Internet don't like JJ for power tubes (often noting that they are fine for preamp tubes). Do you think I should spend a little and upgrade to the TAD 6L6GCM-STR REDBASE, or do you think it's a bad idea to stray away from the short bottle? If you think it's best to stick with the short bottle, should I get the current OEM JJ 5881 tubes, or upgrade to a TAD 6L6 short bottle, TAD 5881, or Mesa 5881?
MT15 Replacement Power Tube Selection
- Thread starter scott_
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andy474x
Knows the Drill
JJ make great tubes and not so great tubes, actually I find their power tubes to be better on the whole than their preamp tubes, especially their ecc83s, which is everywhere as stock tubes and not that great. Since PRS is shipping the MT15 with the JJ 5881, I wouldn’t hesitate to go that way. However, if you have the clearance and want the TAD, the only other consideration I could think of is whether the head shell or handle would get hot with the power tubes that close. But I think you would probably be fine.
I'm actually leaning toward the TAD 6L6WCG-STR which is 5881 size with a 6L6 spec that seems very similar to the Ruby tubes I have now. Maybe I'll try the JJ 5881 next time. I agree with your point about the head shell heat. There is a about 1 inch of clearance with the small bottle tubes, and the inside of the head shell is marked by heat. There would be only about 1/4" clearance a full size 6L6 like the TAD red base. I'm not really concerned about destroying the head shell because it's simply painted metal, but it could result in cosmetic damage or worse, the hot head shell could have some unexpected domino effect. Or it could burn my finger off and I would be relegated to using capos and playing kumbaya songs. If I did want to use a full size 6L6, I would probably modify the shell with additional venting or shielding. The shorter tube seems like a better option. Besides, since the MT15 is so capable of extreme cleans and extreme growl, all I'm really looking for is pure amplification, and don't need any sound enhancement from the tubes.
claythomas
Nothing but the best! But I can't afford it....
I run Mesa SP12AX7's and Mesa 5881's. I feel it's a great combo!
Goran Lorencin
New Member
Hey there, my 5c ... I bought a pair of TAD 6L6GC-STR (as a Duet) and there are no issues regarding the hight, everything works. But comparing the sound of the Ruby`s and the TAD`s, I must say I like the Ruby`s more. Not that there is anything wrong with the TAD`s, but they sound a tad
more compressed/tight, maybe more suited for metal ... maybe ... still a good sound, but the Ruby`s are a bit more visceral, more organic. I also did some swapping of preamp tubes and in the end put a Mullard in V2 or V3 (do not remeber now), cause one 12ax7 was bad anyway, and I put a "special" JJ E83CC (with frame grid) in V6 and everything is spot on. Have noticed that one of the Mullards (bought a matched pair) made my MT15 behave very noisy and saw that by replacing just that one bad Mullard made everything go back to normal and quiet. I learned something new that day.I also noticed that the Ruby 6L6GCMS are obviously not in production any more as they are hard to find. Would love to find a good replacement for not much more money and with the same characteristics, on EU soil. Well, looks like I just found a pair YEEEY!
Anyone tried the Ruby Tubes 6L6GCEH?
RickP
Established 1960, Still Not Dead
As you’re not replacing them often, a nice set of NOS tubes might not be out of line for you. The JAN-Phillips 6L6WGB is a short (sometimes called “stubby”) tube that sounds good and is very solidly constructed… the JAN is a military spec for “Joint Army Navy.” You can find them at a reasonable cost, though that will still be double or more the Chinese and Russian ones.
The SED/Winged C 6L6GC was among the best made, right up there with the vaunted RCA black plates, but they are full height tubes and might be a tight fit. They are my favorite 6L6, and I’ve used them for decades in my Mesa amps, but they are also now sadly out of production. Hopefully my backup supply will last me another 10 years!
The SED/Winged C 6L6GC was among the best made, right up there with the vaunted RCA black plates, but they are full height tubes and might be a tight fit. They are my favorite 6L6, and I’ve used them for decades in my Mesa amps, but they are also now sadly out of production. Hopefully my backup supply will last me another 10 years!
The JAN-Phillips 6L6WGB looks like a good selection. My preferred tube vendor carries them, and unlike some NOS tubes, price isn't crazy.
Hey there, my 5c ... I bought a pair of TAD 6L6GC-STR (as a Duet) and there are no issues regarding the hight, everything works. But comparing the sound of the Ruby`s and the TAD`s, I must say I like the Ruby`s more. Not that there is anything wrong with the TAD`s, but they sound a tad
I also noticed that the Ruby 6L6GCMS are obviously not in production any more as they are hard to find. Would love to find a good replacement for not much more money and with the same characteristics, on EU soil. Well, looks like I just found a pair YEEEY!
Anyone tried the Ruby Tubes 6L6GCEH?
The Ruby 6L6GCEH does look interesting. It would be nice to hear from someone who has tried them. First tubes I'm going to try are the TAD 6L6WGC-STR (with a W). The TAD website says the are "the perfect choice for vintage tweed and blackface amps" as opposed to the TAD 5881WXT which the website says are "more modern and aggressive" and "a special bite in the upper mid range". I'm not really looking for a sound that would be described as a "special bite". If I don't like the TAD 6L6WGC-STR, I may look into the Ruby 6L6GCEH or the NOS JAN-Phillips 6L6WGB/5881 that @RickP suggested.
OP...your tubes are still young. That's not a lot of play time. You should be able to get a few thousand hours easy. There are amps out there with 1000's and 1000's of hours on the tubes that still work great. Basically, if the tube fails in some way, replace it. Otherwise, no need.
andy474x
Knows the Drill
Hey there, my 5c ... I bought a pair of TAD 6L6GC-STR (as a Duet) and there are no issues regarding the hight, everything works. But comparing the sound of the Ruby`s and the TAD`s, I must say I like the Ruby`s more. Not that there is anything wrong with the TAD`s, but they sound a tad
I also noticed that the Ruby 6L6GCMS are obviously not in production any more as they are hard to find. Would love to find a good replacement for not much more money and with the same characteristics, on EU soil. Well, looks like I just found a pair YEEEY!
Anyone tried the Ruby Tubes 6L6GCEH?
I like the new production Mullard preamp tubes a lot, as well as the grid frame JJ which I think they’re calling the e83cc (vs the standard ecc83s). If memory serves, I have some of the Mullards in my MT15, as well as other amps. The thing about the standard JJ ecc83s, for me, is they just have gobs of gain, and overdrive the rest of the amp downstream too much, especially in modern high gain designs that don’t necessarily need that. Using a more modest tube like the Mullards or the grid frame JJ allows the gain factor to ramp up more gradually through the gain stages, rather than go to max compression right away and then just get muddy in the further gain stages.
Goran Lorencin
New Member
I must say though that the JJ ECC83S are sort of sturdy and not as sensitive as Mullards, I noticed that the Mullards are more sensitive when it comes to physical stress and microphonics - or it might just be with my prepamp Mullards as one was already bad when I got them. But there is also the speakers that have to be taken into account, I swapped one of the V30 for a Jensen Electric(or Jet) Lighting (in a 2x12 cab) and the difference is heard clearly, although I have to wire them together (not trough the stereo/mono back panel switch) as I can hear that the Jensen (70W) is more pronounced than the V30 (60W), even if they are both rated at around 100dB - both are 16Ohm.
Goran Lorencin
New Member
Yes, it is sometimes quite a laborious task to find the right tubes for your amp/speaker/guitar/playing style combo. Sadly I do not have the money to buy 10 pairs and test, but you slowly buy stuff trough the years and gradually build up the tube arsenal
sometimes you buy just because of the manufacturers or some players advice, but it does not mean that it will work for you.
Goran Lorencin
New Member
You guys living it the land of Merica have it a bit easier buying tubes as there is much more to choose from and the prices are somewhat lower as the market is bigger ... or I just have still not found the right tube vendor.
Goran Lorencin
New Member
I have noticed that buying tubes based on advice of other players is sometimes tricky, we all strive for different sounds and have different playing styles and gear, therefore taking advice can sometimes make you take the wrong road in the beginning as the end effect can be different when playing trough your own gear. And I mean just sometimes.
andy474x
Knows the Drill
I agree - if there’s something to be said about the ecc83s, it’s that they’re bulletproof. The Mullards do seem to be a little less resilient. I’m hoping that’s just on a tube here and there, we’ll find out when I start hauling gear out of the house again.
I think you are correct. There was no audible issue with the Ruby tubes. In fact, they still sound fantastic. I did notice the bias readings start to drift apart and I assume that means the Ruby tubes may have an issue soon. Maybe that's a bad assumption. Regardless, I swapped the Ruby tubes for TAD 6L6WGC-STR, which are very close to the Ruby tubes in all ratings and physical size, and the TAD website explains the 6L6WGC-STR sound to be what I'm aiming for. At first, the TAD 6L6WGC-STR tubes sounded shrill. After 20 or so hours of use, the TAD 6L6WGC-STR tubes sound great, but I think I may still like the Ruby tube sound a little better. I'm going to use the TAD tubes a little more, then use a looper to record both with equal bias readings and learn. I may end up buying a 3rd set and just have a little fun experimenting. When I make the recordings, I'll post a link here.
Wow. I love this! You must have a bigger brain than me because the thought adding speakers to this conversation blows my mind. I just swapped my V30's for alnicos, and this whole thing is entirely too much
Goran Lorencin
New Member
Wow. I love this! You must have a bigger brain than me because the thought adding speakers to this conversation blows my mind. I just swapped my V30's for alnicos, and this whole thing is entirely too much
Well .. I have a big head, that`s a fact, don`t know about my brain hahaha ... but I know that sometimes I go a bit too deep into a research when it comes to guitar gear and the sound of it. What I know for a fact is that I should PLAY MORE and do more CREATIVE STUFF and then later deal with the finer details of the sound. Getting lost in the search for the "perfect" tone is not good for musical creativity and does not compensate for good playing technique or standard practice, I just have to start playing more. But yes, the speakers are in a way almost as important as the tubes when it comes to sound character imo. We just usually don`t have 10 cabs with different speakers to try out to hear the difference.
Scott do you have a 2x12 or 4x12? What kind of music do you play? Is it the music style that made you want to swap the speakers or did you just want a different sound?
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Lately I play blues jazz and country, clean with compression, reverb, delay, and sometimes a little transparent overdrive on a 1x12 with a Jensen alnico. However, sometimes when I have the house to myself, I crank it to 11 and play anything from classic hard rock to 90's rock to progressive metal, which sounds great on my 2x12 with v30's, which is more often used as a shelf.
So yes, I choose speakers for the style of music. For tubes, I'm really aiming for purity. Since the MT15 has an effects loop and such a pristine clean channel, I can augment tone with mild effects. Since the MT15 has an absolutely screaming lead channel, I need nothing else for metal. Therefore, any "breakup" or frequency response tuning comes from effects and speakers.
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Goran Lorencin
New Member
I agree, the MT15 really has a pristine clean channel that takes effects like a champ. I also strive for a crisp and detailed sound, be it clean or lead channel, and because of that I also fiddled around with different preamp and power tubes and with speakers as well, that is why I paired the Jensen with the V30, it is a bit more tame(breaks up a bit later) than having two V30s in my 2x12 cab ... although for a purely hc/metal/heavy sound the V30s are an awesome combination with the MT15. For jazz/blues/country you could also try a 5771 or 12at7/12au7 in preamp positions 1,2 or 6, they are a bit smoother ... if you should need less power.
How is your FX loop, do you have any issues with the hum/noise when using it? I had some issues with that before I changed some tubes, have to test again to see if anything changed, because I noticed that a bad preamp tube can make quite some noise.
