Badlander Retube

[incertracing]

Hey, i just got a 100w badlander used and i really love it. I usually retune all my amps with JJ's and make sure my tech re-biases everything so it slams. Is this possible with the badlander or is it fixed? Does it make sense making the jump to JJ's? If no where do i get tubes if i need to re-tube, sweetwater?
Thanks.

 

[tbonesullivan]

All Mesa Boogie amps are fixed resister bias, and they do not have a bias trim pot. You can however have them modded to have one installed, though most Mesa designs get most of their sound from the preamp design, and not having a power amp biased at 75% dissipation.

 

[bandit2013]

Mesa 12AX7 preamp tubes are JJ ECC83s to start with. Just note that preamp and power tubes can be difficult to get these days. If you find inventory, get tubes and a few extra if your budget can support that move so you have something on hand.

As tbonesullivan stated, Mesa uses a fixed bias design.

The Badlander may have the EL34 power tube as its primary tube choice, it is advisable to stick with the Mesa branded tubes as they will fall within speck to the fixed bias. The Badlander may have the Rectifier name on the front panel, it is quite different than the traditional Rectifiers before it. This amp sounds best if you get into power tube saturation/distortion. I recommend the bias colors green, grey, and blue for the EL34 tubes, STR447 (EH EL34) or STR446 (TAD red base EL34). I actually prefer the STR446 tube but I have no complaints about the STR447 either. Both work great in the Badlander.

The other option is the 6L6GC tube. Just set the bias switch on the back of the amp to match the tube type used. For optimum performance with the 6L6GC tubes, I have two recommendations: Mesa STR445 ( JJ 6L6GC) or STR448 (TAD red base 6L6GC). Request green or gray bias colors for these two choices.

Mesa power tubes are categorized by bias ranges using a color code: Red, Yellow, Green, Grey, Blue, White. The Red bias color will provide more headroom, less early distortion, at the other side of the spectrum, white will have the least amount of headroom and early distortion characteristic.

The STR445 green and STR448 grey I have used in the Badlander with great results and aggressive tone and grind character. I have also tried STR448 red, those lacked the characteristics I wanted. Note that the 6L6GC characteristic will be different than an amp that was primarily intended to run the 6L6GC tube. However, this will not pose an issue with the 6L6GC tube use, make sure you set the bias switch on the back panel of the amp to match the tube type (EL34 or 6L6). In most cases, you can get the same characteristic with the 6L6GC with a hotter bias color (green, grey), running a colder tube like the red or yellow may not be as rewarding. With the Badlander, the same may hold true with the EL34 which generally run in the green, grey and blue range. I have not seen those in yellow or red.

Green is the middle bias color. I am not sure what the difference in plate current between the bias colors are. If you find any whites, do not get them, they will be too saturated. Not even sure tubes that fall into that color range are even available.

 

[incertracing]

Thanks

 

[incertracing]

Mesa 12AX7 preamp tubes are JJ ECC83s to start with. Just note that preamp and power tubes can be difficult to get these days. If you find inventory, get tubes and a few extra if your budget can support that move so you have something on hand.

As tbonesullivan stated, Mesa uses a fixed bias design.

The Badlander may have the EL34 power tube as its primary tube choice, it is advisable to stick with the Mesa branded tubes as they will fall within speck to the fixed bias. The Badlander may have the Rectifier name on the front panel, it is quite different than the traditional Rectifiers before it. This amp sounds best if you get into power tube saturation/distortion. I recommend the bias colors green, grey, and blue for the EL34 tubes, STR447 (EH EL34) or STR446 (TAD red base EL34). I actually prefer the STR446 tube but I have no complaints about the STR447 either. Both work great in the Badlander.

The other option is the 6L6GC tube. Just set the bias switch on the back of the amp to match the tube type used. For optimum performance with the 6L6GC tubes, I have two recommendations: Mesa STR445 ( JJ 6L6GC) or STR448 (TAD red base 6L6GC). Request green or gray bias colors for these two choices.

Mesa power tubes are categorized by bias ranges using a color code: Red, Yellow, Green, Grey, Blue, White. The Red bias color will provide more headroom, less early distortion, at the other side of the spectrum, white will have the least amount of headroom and early distortion characteristic.

The STR445 green and STR448 grey I have used in the Badlander with great results and aggressive tone and grind character. I have also tried STR448 red, those lacked the characteristics I wanted. Note that the 6L6GC characteristic will be different than an amp that was primarily intended to run the 6L6GC tube. However, this will not pose an issue with the 6L6GC tube use, make sure you set the bias switch on the back panel of the amp to match the tube type (EL34 or 6L6). In most cases, you can get the same characteristic with the 6L6GC with a hotter bias color (green, grey), running a colder tube like the red or yellow may not be as rewarding. With the Badlander, the same may hold true with the EL34 which generally run in the green, grey and blue range. I have not seen those in yellow or red.

Green is the middle bias color. I am not sure what the difference in plate current between the bias colors are. If you find any whites, do not get them, they will be too saturated. Not even sure tubes that fall into that color range are even available.

Wow thanks so much for taking the time to help me, i didnt know all of this. Im not even sure what the amp came with, it sounds great thow. I want the amp to be its fullest and loudest and most brutal, would that mean running the tubes hotter? Forgive me im used to 5150's where we bias a lil hotter and i use JJ's and they sound killer. Is it that red is coldest and white is hottest in terms of power tubes? Can i run JJ's, i spoke to Eurotubes (who are my tube supplier) and they told me to let them know the amp its for and they will give me EL34s to match the plate voltage needed.

 

[bandit2013]

Yes, the red would be colder or have more headroom. You would need to bias those with more plate current to have the same effect of the green bias color tube. The Blue or White (assuming it exists) would require less bias current to be similar to the green bias color. As for how much of a difference, unknown. It does not take much in bias voltage to extract more plate current.

Original tubes the Badlander comes with are the STR447 as this should be printed on the glass of the tube if they are Mesa tubes. Bias colors can range from green, grey, and blue. I am currently running a pair in blue and a pair in green. Since I have two bads, I wanted them both to be as close to each other as possible so I mixed the pairs of tubes since one came with the blues and the other with greens. I can tell the difference. STR447 are the Electro Harmonix EL34 tubes. Not sure what the selection criteria is. Plate voltage, never measured it. I would assume it is in the 450VDC range or higher. I have yet to see a schematic of this amp and have not measured any voltages. I would not doubt it is closer to the MWDR in terms of plate voltage, 480VDC? I did not see the Badlander on their list of retube kits.

Just a note: there is one DC coupled cathode follower circuit use in V2 and one cathode follower in V4. The rest are standard 12AX7 circuits. Not sure if the E83CC tube is a good candidate for the cathode follower positions, the standard ECC83S will be just fine. I did get a set of the E83CC tubes to try out. Never got there yet. They are supposed to be an improvement.

EL34 type, not sure which one would work best. Not too familiar with the JJ EL34 tubes. However, my EVH 5150 iiis EL34100W amp has a quad of them. I do not know the difference between the EL34, EL34L and the EL34II.

If you want the mean and nasty sound go for the 6L6GC tubes. They have reference to Mesa tubes I am sure. Ask for what would be equivalent to green bias color.

 

[incertracing]

Thanks, how do i know the bias colour of the tube? Where do i look?

This is the response from euro tubes about the badlander. Tell me what u think.

"The important thing when swapping power tubes in a Mesa is that you put an appropriate grade (plate current) of tube in there. What grade is appropriate? Well that depends on the amp and the tube type. It usually breaks down like this: 6L6 Mesa amps need super hot (high plate current) power tubes. EL34 Mesa amps need very cool (low plate current) tubes. EL84 Mesa amps also need very cool tubes. That also goes for Mesa amps that can take either 6L6 or EL34 like Triple Recs and so forth...it is still hot 6L6 and cool EL34.

Here at the shop we usually like 6L6 in Mesa amps. They are mid-scooped with extended high and low end, and cover more sonic territory than an EL34. That's the American tube sound. EL34 types are mid focused with less high and low end. That's the British/Marshall sound. EL34 don't sound bad in Mesa's...but we like 6L6.

If you do want to try some EL34 type in your Mesa, take a look at the EL34II. We like the way they sound in Mesa amps and they tend to bias a little more willingly. The E34L can work also, and sounds good, but they generally test as being rather hot and are finicky about biasing properly.

If you order some fresh tubes from us, be sure to leave a comment or drop us an email and tell us that the tubes are for a Mesa amp and we will select an appropriate grade of tube for you."

 

[incertracing]

So got a chance to take a pic of the tubes that are inside the amp, its STR 447. How do I know what colour it is? I dont see any colour designation.

 

[tbonesullivan]

So got a chance to take a pic of the tubes that are inside the amp, its STR 447. How do I know what colour it is? I dont see any colour designat

The color should be on the labels on the base of the tube. You may need to remove the tube to read them. They will be three letter abbreviations like RED, YEL, BLU, GRY, GRN, etc.

 

[incertracing]

ok thanks will check.

 

[bandit2013]

Yep, the color is on the label. Note that red through blue will work just fine in any of the Mesa amps. Reds will sound weaker, blues will sound more saturated. Most of the EL34 tubes Mesa sells fall in the green, grey and blue bias colors. I have yet to come across any other colors, it does not mean it does not exist. The Triple Crown 100 and 50 use the exact same power tubes. That amp runs at 450VDC plate voltage. Not sure where the Badlander runs though. Since MESA tubes will work in any Mesa amp unless it is a vintage IIC+ with the 105 transformer and operating at 500VDC plate voltage, that would require the STR415 tube which is a NO Sylvania special tube request which usually run in the green bias color range. Different tube which can support the higher plate voltage.

You can use the TC50 retube kit on Eurotubes as a baseline, They suggest the EL34L for that amp. I assume the L stands for Low impedance. I am not sure what is compatible with the Mesa STR447 tube in the JJ lineup. If you want to retain that vintage vibe or old school sound, stick with the EL34 tubes but which version of JJ is equivalent to the EH EL34 is unknown. If you want to toast a Mark VII amp with more usable gain on tap and yet retain note detail that is on par with the JP2C, opt for the Mesa STR445 tube, that is the same tube as the JJ 6L6GC. Green bias color works but not sure what that plat current is or the plate voltage. The Same JJ 6L6GC tubes for the JP2C model will work in the Badlander just as well. Since the JP2C has the same number of preamp tubes, that would be easy.

I believe they are confused with the Badlander having it classified as a Rectifier amp, it is far from it.
Not sure what to suggest for the EL34 tubes for Eurotubes. If they have an understanding of the Mesa bias colors for the EL34 tube, since they have suggested such for the TC50, I would assume the same would hold true for the TC100 and Badlander since they use the same tubes. If you opt to get Mesa power tubes, look for the STR447 in green, grey, or blue. You can also opt for the STR446 EL34 in the same bias colors. the STR446 is the TAD red base EL34 tube. I thought they sounded much better than the EH EL34 (STR447).

 

[bandit2013]

Based on the description of the JJ EL34 tubes, the EL34L is what they prefer. I would ask for the same tube they recommend for the TC50 in terms of plate current. It appears that they have no information on the Badlander, probably because more recent amps are not available in Europe. I am surprised that Eurotubes has not done any research on it yet.

You can select one of the tube kits for the TC50, select customize, delete the ECC81 (12AT7), change the number of standard ECC83s tubes to 4 and the balanced ECC83s to 1, and then add one more pair of the EL34L. Badlander has 5 preamp tubes, ECC83s with one balanced, EL34L tubes matched for a TC100 would be the ideal. TC50 has two less tubes and it uses the same tubes as the Badlander.

 

[incertracing]

So euro tubes is saying that i can run the EL34 II thats what they recommend for the Badlander. They also say they suggest the 6L6GC but they will select a hotter 6L6 so that it runs the way it should so you get the sonic difference without a loss of gain and output. I think if i can afford it i may try both.

 

[bandit2013]

I read through the description on the EL34II and the EL34L. If you opt to change to the EL34II, get a mental image of the STR447 in your head and listen to the note definition at a moderate gain setting, say at noon or 2pm (crunch and crush).

As for the 6L6GC tube being hotter, I would agree. The BAD relies on that power tube distortion more than you would think it does. It is not a Rectifier in the sense of the Dual Rec Roadster (need more headroom tube or it will get muddy), The MWDR can run a hotter bias tube which is in the grey color. Green is basically middle of the road. The BAD runs well with the Greens but going hotter than that with the JJ 6L6GC may be over the top as it is a very aggressive sounding tube in all respects. I really like the Mesa STR445 (JJ 6L6GC) in the Badlander, with those tubes in the amp, crunch will have more usable gain than the crunch of the Mark VII. Crush is on par with the IV mode of the Mark VII or CH2/CH3 of the JP2C. If you want the grind of a IIC+ without forking out the high dollar to get one, the JJ 6L6GC is one way to get there with the Badlander.

When using the EL34 tubes, the sonic footprint is different. Crunch will sound closer to the rectifier and the crush will be more like the VII mode of the Mark 7. The perceptual gain will be less but still good in all its glory for that old school 60s-70s rock. Since I have a Mark VII, I will probably return the Bad to using the EL34 tubes which keeps it different.

EL34 or 6L6GC, the Bad has similar sonic qualities of the JP2C, meaning it retains note detail no matter how much gain you muster in the preamp. That to me is an edge over the Mark VII in all respects as the Mark VII does not seem to hold onto that characteristic unless you change the power tubes to a colder bias to compensate for the tube saturation you get with Simul-Class power output.

I would consider the standard ECC83s tubes vs the HG version or you may get tube ping when changing channels or worse, self oscillation (microphonic issues). I did try some higher gain 12AX7 tubes just for kicks, that made it more difficult to get to gig level without backing off on the gain since it would push the amp into uncontrolled feedback. Perhaps if they can offer the same grade of ECC83s as the one's Mesa uses. I never got around to trying the E83CC tubes in the Badlander yet. they are a bit different than the standard ECC83s tubes. Just keep in mind that the V2 and V4 have cathode follower circuits, V2 is that dc coupled cathode follower circuit common with the Rectifier amps and V4 just has the typical cathode follower circuit use for the FX send circuit. That leaves just V1 and V3 to mess with, it is basically a Mark lead drive circuit. Phase inverter is typical Mesa design so a match triode tube is needed. That can be HG if they recommend it. It may be fine to use all HG in the V1 and V3 as well. V3 has the triode circuits with the higher gain. This was based off of the tube task chart in the manual and after poking around the amp with a multimeter to find what the plate resistor and cathode resistors used in the preamp are. The Badlander is a hybrid, combination of the Mark lead drive circuit on the front end, followed by a traditional tone stack driver and FX circuit of a MWDR.

If they need the resistor values (measured with a multi-meter),

V1A plate: 100K, V1A cathode: 3k
V1B plate: 82.5k, V1B cathode :1.5k
V3A plate: 270k, V3A cathode: 3.3k
V3B plate: 130k, V3B cathode: 1.5k.

 

[incertracing]

So I took a look at the tubes last night and the only designation I could see was on the grey area at the bottom of the tube that had BLU, I’m assuming that’s the blue heat range?

 

[bandit2013]

Yes, that is correct. Common bias colors I have come across with the STR447 are green, grey, and blue. Blue will have early onset of tube distortion vs green. When it comes to the STR447 tubes, there does not seem to be much of a dramatic difference between them. I am currently running a pair of greens and a pair of blues in both Badlanders since I am using them in stereo, I wanted a good balance with the two amps. One came with all greens, and the other came with all blues. I have yet to find any STR447 in the red or yellow bias colors. The bias color is based on a standard tube as a reference. Not sure about the EL34 as which Mesa used as a standard, it could be the old STR416 big bottle 6CA7 they used in the 1980's, or it may be the STR450 NOS Siemens EL34 (do not use the STR450 in a Badlander or TC series as the plate voltage is too high). As for the 6L6 tube, the gold standard is the STR415 NOS Sylvania tubes. Those were specifically manufactured to sit in the green bias color range based on plate current. What I have tried in the BAD is the STR445 (JJ 6L6GC tubes) in the green bias color and they are epic. They were way too hot for the Roadster and MWDR though. With the STR448 (TAD red-base 6L6GC) I ran grey bias colors with really good results. If Eurotubes can decipher the Mesa bias color, I would recommend to have a match for the Mesa green in the 6L6GC or you will get too much power tube saturation effect. The STR445 green bias color tube is really, really good if you want to have an amp that will compete with a Mark IIC+ or JP2C running with the STR415 tubes. So, in other words, you can request the bias of the JJ 6L6GC they would recommend for the JP2C. I have also tried the STR445 greens in the JP2C and it was really close to the STR415 character. That was a surprise.

 

[incertracing]

Yes, that is correct. Common bias colors I have come across with the STR447 are green, grey, and blue. Blue will have early onset of tube distortion vs green. When it comes to the STR447 tubes, there does not seem to be much of a dramatic difference between them. I am currently running a pair of greens and a pair of blues in both Badlanders since I am using them in stereo, I wanted a good balance with the two amps. One came with all greens, and the other came with all blues. I have yet to find any STR447 in the red or yellow bias colors. The bias color is based on a standard tube as a reference. Not sure about the EL34 as which Mesa used as a standard, it could be the old STR416 big bottle 6CA7 they used in the 1980's, or it may be the STR450 NOS Siemens EL34 (do not use the STR450 in a Badlander or TC series as the plate voltage is too high). As for the 6L6 tube, the gold standard is the STR415 NOS Sylvania tubes. Those were specifically manufactured to sit in the green bias color range based on plate current. What I have tried in the BAD is the STR445 (JJ 6L6GC tubes) in the green bias color and they are epic. They were way too hot for the Roadster and MWDR though. With the STR448 (TAD red-base 6L6GC) I ran grey bias colors with really good results. If Eurotubes can decipher the Mesa bias color, I would recommend to have a match for the Mesa green in the 6L6GC or you will get too much power tube saturation effect. The STR445 green bias color tube is really, really good if you want to have an amp that will compete with a Mark IIC+ or JP2C running with the STR415 tubes. So, in other words, you can request the bias of the JJ 6L6GC they would recommend for the JP2C. I have also tried the STR445 greens in the JP2C and it was really close to the STR415 character. That was a surprise.

So based on your extensive knowledge and teaching i decided to ask mesa if i could buy specific colours in the el34s and his response was interesting.

"Hey Scott
Thanks for reaching back. Being the Mesa amps are a fixed bias amp, we have a very narry window of what we considered to be acceptable tubes for our amps, so the window is very narrow and there is really not much difference between the color codes. The color codes are purely for internal matching purposes only and really have little impact in the tone or volume of the amp."

Why are they taking this stance, is it because of availability of tubes?

 

[domct203]

That has always been their stance.

While I’m not going to get into the tone aspect of it, there is a measurable difference in plate current among the colors, it doesn’t seem narrow to me.

Dom

 

[bandit2013]

I believe their stance on the color bias code field having a narrow effect is probably correct, but the little impact on tone or volume of the amp is not very accurate. Perhaps with the STR447 (EH EL34) tube, there is not much of a difference in tone, sound quality or distortion/saturation between the GRN, GRY or BLU. Not sure if that holds true with the STR446 (TAD red base EL34) as I only have one quad. Felt they had better sound quality and good overall character compared to the EH EL34. I will have to dig them up to see what bias color I got in those.

When it comes to the 6L6GC variety, that comment does not hold up. That narrow field is not as narrow as they think it is. The current production 6L6GC tubes do not compare to their gold standard STR415 Sylvania tubes (those will generally be GRN bias). Reds will work best in amps that do not favor power tube saturation like the Roadster or Mark V90. Some amps work best with green or grey bias colors like the MWDR, JP2C and the Badlander. Mark VII sort of falls into the yellow range or it will saturate too much at gig level and loose its composure.

The STR445 (JJ 6L6GC) I have tried in yellow and green. I do not have other bias colors. Greens were too much for the Mark VII (stock tube) as it drowns itself at gig level volume. Yellows improved that issue considerably, way better. Considering yellow is one step to more headroom than green. The greens or GRN were ideal in the Badlander and JP2C. I found the GRN bias color to be a good match for the STR415 Sylvania 6L6GC tubes as I have a quad of those I got just last summer.

The STR448 (TAD red base 6L6GC) I have red, yellow, and grey. The grey bias colors were awesome in the Badlander and the JP2C. I sort of like them a little better than the STR415 as it adds just a little bit of air to the sound, hard to describe it but nice tubes. Red bias color, they were lame. Too much headroom and no power tube distortion, sort of took the live out of the amp. They were not good candidates for the Roadster, MWDR or Mark VII (unless I blend then with the STR445 tubes).

At least we have a variety of the 6L6GC tube offering now. Before, it was the STR440 tube and that is it. One tube fits all is not true. Bias colors really make a difference and is dependent on the amp it is used in.

 

[incertracing]

Thanks, would you say the ^L^ is an option i should consider for the badlander? Is there a noticeable increase in low end?