Do these tubes make my butt look big?

[andy474x]

After (sadly) close to 4 years of use in my SE30, I finally got around to changing my original power tubes the other day. Yes, it's almost a crime that they had been in there that long. But life was busy and money was short, and the amp still sounded good. I was contemplating a few things, maybe new 5881's (stock spec), maybe some 7581's (think 6L6 with 35 watt max), or just plain ol' 6L6GC's. Over the weekend I got to thinking about how I've always loved the sound of a good 6L6 amp, Fenders, Mesas, etc., so I decided to just go plain vanilla and grabbed a matched pair of JJ's from the shop. Had them in and biased in about 10 minutes Saturday afternoon (THANK YOU DOUG for external test points and trim pot). I only had a few minutes with them that day, and they sounded... normal. Ok, well I felt like a good boy for changing them I guess.

Came back to it Sunday, and really had time to work those tubes. Got to fiddling with my EQ, and noticed a big difference in the bass response. With the stock 5881's, as volume increased, the lows could get wooly and the highs lose definition if I didn't make the right adjustments. I could still dial the amp in, but different places on the MV changed the tone dramatically and I always had to adjust for that. With these new tubes, the bottom is still HUGE, especially for a 30 watt amp, but the response stays tight and defined everywhere. Slight adjustments are still necessary with drastic MV changes, but for the most part it's the same amp all over the dial now. I guess I'm just a 6L6 guy! Definitely getting my ideal mix of big low end with mids and highs that have the right mix of cut and sizzle, but also a creaminess at the very top. Just right with gain so I can engage my Clarksdale (TS) and get a little more focus in the upper mids without being piercing. Add some delay and it's a juicy, screaming tone without sounding like a box of bees. Love it.

I don't know if the old 5881's were worn out, or if that's the way they've always been. I do seem to remember the amp wanting to sound a little muffled and loose at higher volumes, nothing I couldn't adjust for, but these new tubes have me dialed in. I must admit, though I've not had tons of tube amps, I've never met one that didn't like JJ's.

My bottom was big and flabby. Now it's still big... but tighter. More defined. And I think we all know what they say about fat bottomed amps.

 

[toothace]

Great to hear Andy...Drive that low end!

 

[sergiodeblanc]

I like big butts.

 

[bodia]

You know what they say...."Fat bottomed girls you make the Rockin' world go round."

 

[László]

5881s are great output tubes, but they don't have the balls of a good 6L6, and the 6L6 high end is sweeter. Generally speaking, of course.

The 5881s will break up a little sooner, so yeah, adjusting the controls matters.

 

[andy474x]

5881s are great output tubes, but they don't have the balls of a good 6L6, and the 6L6 high end is sweeter. Generally speaking, of course.

The 5881s will break up a little sooner, so yeah, adjusting the controls matters.

Yeah, exactly what I'm hearing, It's that big, full attack that a lot of 6L6 amps have that resonates with me. Although I don't own one, I've always liked the sound of the Blues Deluxe, and the newest iteration of the Hot Rod Deluxe as well. Great 6L6 amps, I think a lot of people overlook them because they're so common and there's nothing new or exciting about them, but to sit down and play one and have a great sounding plug and play amp at that price is impressive. I'm talking mostly as a clean platform, but they take pedals very well which is part of their magic too. For all the new stuff that comes out, they stand the test of time. Same with the Lonestar, great tones - love what Andy Timmons has done with that amp. And then there's the Dual Rec, although I'm not strictly a high gain player I've always liked the punch they have without getting fizzy on top. Tons of other amps have 6L6's, but when it comes to the good ones, whether they're vintage themed, clean machines, or gain monsters, they all have that full, punchy bottom and a nicely positioned treble. Of course, there are dozens of different variables inside a given amp, but the tubes play a part.

Why Doug and Paul chose the 5881 for this amp, I'm not sure - like you said, they're not bad tubes, but with what I'm hearing I think the 6L6's would be the more popular choice. I'm sure they had their reasons, and that they were good reasons. Regardless, this is the glory of tube heads, rolling some tubes and finding new tones. Just like different kinds of strings on a guitar.

 

[László]

Why Doug and Paul chose the 5881 for this amp, I'm not sure - like you said, they're not bad tubes, but with what I'm hearing I think the 6L6's would be the more popular choice. I'm sure they had their reasons, and that they were good reasons.

Well, for one the earlier breakup, slightly lower power, and less headroom means that a 5881 amp pleases a lot of folks who want to hear the power tubes dishing out a little grit.

I had a Two-Rock with small bottle 5881s, and it was a blues machine par excellence. People love that stuff. If memory serves it came with NOS JAN Phillips tubes. So a lot depends on the tube you're using to get the job done.

 

[LJD]

Power tubes should last for more than 4 years, right? I mean, I don't change a tube until something starts going wrong. The 6L6's in my twin were there for 22 years of jamming and giging, no problems.

 

[Boogie]

Power tubes should last for more than 4 years, right? I mean, I don't change a tube until something starts going wrong. The 6L6's in my twin were there for 22 years of jamming and giging, no problems.

+1
Don't feel like you're neglecting your amp if you don't routinely change the power tubes, celebrate! Unless you don't like the tone, changing power tubes should be because of failure, so if they don't fail, you don't have to swap. Long lasting tubes can be kinda rare today.

 

[László]

In the old days, players rarely changed tubes unless a tube failed. I'm pretty sure I went at least decade or so on my old BF Bassman head. But a lot depends on how often one plays, how long one plays for, and of course Boogie's right, the newer tubes often aren't as long-lasting, because they're mainly made on very old equipment that's out of tolerance, etc.

When I played Two-Rock amps, the guys recommended an output tube change every 6 months for players who gigged the amps frequently, but only changing preamp tubes if something failed or a player wanted to change the tone.

I practice daily, and record often, but only with one amp at a time. I only find the output tubes in my amps need changing every few years; again, this depends on the tube. So far I've had very good luck with the Winged C that came in my HXDAs, and I've already got a couple of years on the EL84Ms (NOS Russian Military, rated 50,000 hours!) that came in the DG30, and the amp still sounds amazing. But I've had a couple of the JJ preamp tubes go microphonic or get noisy, so I've replaced the ones in my HXDA with NOS. The DG 30 came with 2 NOS, and 2 JJs, and one of the NOS and one JJ went south and needed replacement. However things have been stable for over a year, so I'm not expecting further problems.

 

[Tahlee]

"Do these tubes make my butt look big?" haha - great title

 

[Deleted member 5962]

Andy, I'm not normally one to point out stuff like this, but since you asked... Yes, they do.

 

[The Fight]

Wow man that's a long time wait to change power tubes! I usually change mine every five months to a year, mostly depending on how much I play. Fresh broken in tubes are just so great, they really wake up your ears. Its very interesting how your hearing adapts and you'd never know the difference. Except when it's denial haha.

 

[Deleted member 5962]

I'm sure you know this, but different amps have very different amounts of time the power tubes can last. My Budda said to replace them every 6 months if you played it regularly, because it was biased hot to sound better but that would wear them faster. Some Mesa's are biased cold and tubes can last years in them with little degradation.

 

[CVS]

Power tubes should last for more than 4 years, right? I mean, I don't change a tube until something starts going wrong. The 6L6's in my twin were there for 22 years of jamming and giging, no problems.

Someone must be watching out over you! In general, It seems like I have to replace tubes every 2-3 years on both of my tube amps (they are used almost everyday)

 

[Dusty Chalk]

I'm sure you know this, but different amps have very different amounts of time the power tubes can last. My Budda said to replace them every 6 months if you played it regularly, because it was biased hot to sound better but that would wear them faster. Some Mesa's are biased cold and tubes can last years in them with little degradation.

True. In addition, it also helps depending on how good the power conditioning is, both inside and outside the amp. A good clean power supply will tentuple the life of your tubes.

 

[László]

True. In addition, it also helps depending on how good the power conditioning is, both inside and outside the amp. A good clean power supply will tentuple the life of your tubes.

Not that I know enough to disagree with you, but I don't see how this is could be the case, so please elaborate.

As I understand it, the primary causes of tube wear are: emissions from leaks in the tube envelope, extraneous gases in the tube, failure of the tube seals, deposition of junk from the gases on the tube parts, the constant heating and cooling cycle, damage to the plate materials caused by heavy use of the tube, vibrations, over-voltages, etc.

Of all these, vibrations inside combo amps due to the proximity of the speakers are a major culprit, which is one reason so many players prefer heads and separate cabs to combos. Of course, they then stick the head on top of the cab, where it's going to vibrate anyway...just not as much.

Of these, only over-voltages will be prevented by a power regulator, and that is different from a conditioning device that merely filters noise and hash from the line.

In fact, according to Mesa, under-voltages actually lengthen tube life - they claim that the Variac on my Lone Star will increase output tube life if used (I don't actually use it much).

I've used very high end power conditioners in my studio for about 15 years now. In my old studio, I had a 2KVA Sola isolation transformer, and in my current studio without tape machines and a big console to power, I use a 1KVA Equi=Tech that regulates the voltage, provides balanced power (much like a balanced audio line), and has the expected filtering. My amps have been powered with these devices for a long time.

Recently, I got a Furman P-1800 PFR that conditions power, has a 45 amp reservoir the amps can draw on, and has automatic shutdown in case of over-voltage or under-voltage, though it isn't a power regulator. I use this with the amps because I moved them to a different part of the studio.

All that said, from 1966 - 2000, I just powered my amps from the wall socket.

The output tubes that lasted the longest were the tubes that came with my '67 Fender Bassman that I bought new. I think they went at least ten years. That has more to do with the tube quality of the old tubes than any power filtering, etc.

In modern times, I've had a lot of amps, but I've noticed no difference in the life of power tubes between powering the amps with the SOLA, a Furman IT1220 balanced power supply I once had, the Equi=Tech, or the wall socket.

So I'm not calling BS, but I'd like to know how you've found this to be the case.

 

[Deleted member 5962]

Not to speak for him, but power regulation certainly can extend the life of tubes. Think about it this way. Tubes biased "normally" at 120V may be fairly hot at 127v, so if your power runs hot in your home, your tubes are running hotter than that amp run at lower voltage.

 

[László]

Not to speak for him, but power regulation certainly can extend the life of tubes. Think about it this way. Tubes biased "normally" at 120V may be fairly hot at 127v, so if your power runs hot in your home, your tubes are running hotter than that amp run at lower voltage.

Yes, that part I understand, as I said in my post, over-voltages kill tubes. So voltage regulation can be a good thing.

But that hasn't anything to do with "clean power."

 

[Deleted member 5962]

in theory, clean power should make it sound better, regulated power should make it at least more consistent. Possibly better depending on if your power runs lower or high, and of course, how any individual amp responds to the change. A lot of people run bias hot and say it sounds better (Budda, for example, and their amps do sound great, but go through power tubes quickly). For those on which you can easily adjust bias, like my PRS amps, you'll also find that you can bias it more for lower volume use (like half or less on the master for example) or for more wide open use. Many guys who never turn the amp past half can get better tone by biasing the amp a little hotter, since without ever opening it way up you never really get the tubes over biased by doing so. I'm sure you guys all know that. But in some ways, voltage variations do something similar, but to the whole amp not just the power section.