My favorite amp is my Mesa studio caliber. I bought it used about 13 years ago. I play it about 2-4 hours a week on average. I don't know how old the ones are that are in there but they still glow. I set it just on the verge of breakup. Will I notice if I put new tubes in it? It's $128 for a new set from Mesa. Hate to waste the cash...
Will I notice new tube in my Mesa?
- Thread starter geckoeyes
- Start date
CaughtLikeFire
New member
Re: Will I notice new tube in my Mesa?
the power tubes need to be changed at that age/useage level (way overdue). if you like the sound of the preamp and all the preamp tubes are functioning properly, leave them alone. Using different brands/types of preamp tubes is one way to shape your tone.
for power tubes, you don't need to buy Mesa tubes. Groove Tubes in a #4-6 rating (and in my experience, #7 too) will drop right in and bias up just fine. any good tube vendor (I use Dougstubes.com) can also select tubes in a range that is safe for a fixed + non-adjustable bias Mesa.
If you play your amp at the point of power tube breakup, you will definitely appreciate a new set of power tubes.
the power tubes need to be changed at that age/useage level (way overdue). if you like the sound of the preamp and all the preamp tubes are functioning properly, leave them alone. Using different brands/types of preamp tubes is one way to shape your tone.
for power tubes, you don't need to buy Mesa tubes. Groove Tubes in a #4-6 rating (and in my experience, #7 too) will drop right in and bias up just fine. any good tube vendor (I use Dougstubes.com) can also select tubes in a range that is safe for a fixed + non-adjustable bias Mesa.
If you play your amp at the point of power tube breakup, you will definitely appreciate a new set of power tubes.
ACH91332
New member
Re: Will I notice new tube in my Mesa?
I would replace the phase inverter too.. they take a beating almost almost as much the power tubes do. Every year I retube my power tubes because I use my Marshall so much and I usually replace the phase inverter as well. It's just an extra $10-$15 so why not right? But I use a JJ 12AT7 which isn't pricey.
Being that you've had it 13 years the power tubes are waaayyyy overdue so jump on that. Get a phase inverter too because no matter what after 13 years it is probably shot as well. If you don't really know how to bias your power tubes or don't want to pay someone to do it, try as hard as you can to find out exactly what your power tubes are and get the same set. No matter what you should rebias but you should be fine if its the same tubes. The "MESA" tubes are prolly rebranded tubes. I doubt MESA makes tubes. Odds are you will have to re bias though. I doubt tubes made 13+ years ago were made to the same specs as today's tubes.
As for the preamp tubes, if the amp is squealing more than it should after you replace the power tubes you might need new ones but I doubt it. Preamp tubes last forever.
I would replace the phase inverter too.. they take a beating almost almost as much the power tubes do. Every year I retube my power tubes because I use my Marshall so much and I usually replace the phase inverter as well. It's just an extra $10-$15 so why not right? But I use a JJ 12AT7 which isn't pricey.
Being that you've had it 13 years the power tubes are waaayyyy overdue so jump on that. Get a phase inverter too because no matter what after 13 years it is probably shot as well. If you don't really know how to bias your power tubes or don't want to pay someone to do it, try as hard as you can to find out exactly what your power tubes are and get the same set. No matter what you should rebias but you should be fine if its the same tubes. The "MESA" tubes are prolly rebranded tubes. I doubt MESA makes tubes. Odds are you will have to re bias though. I doubt tubes made 13+ years ago were made to the same specs as today's tubes.
As for the preamp tubes, if the amp is squealing more than it should after you replace the power tubes you might need new ones but I doubt it. Preamp tubes last forever.
Re: Will I notice new tube in my Mesa?
Mesa/boogie amplifiers are made with a fixed bias that cannot be adjusted without digging into the amp and modifying resistor values in the bias power supply. They don't re-bias when you put new tubes in. You put the new tubes in, and go. That's it. I agree that at 3-4 hours a week for 13 years the power tubes presently in there are long overdue for replacement. Contact Mesa, Groove Tubes, or the tube vendor of your choice and let them know you have a Boogie you want to re-tube. Any tube vendor worth their salt should be able to match up a set of tubes that will bias properly in your amp.
The phase inverter does drive the power tubes, but is still a normal preamp tube. It handles preamp levels of power, which are a couple orders of magnitude less than the level of power the power amp puts out, so there shouldn't be a reason why the phase inverter would need replacing alongside the power tubes, IMO.
Preamp tubes do last a long time. Hell, I've got some 1960s RCA tubes in my Nomad, and they're doing just fine. If none of the tubes are acting microphonic, then the preamp is fine and shouldn't need replacing. If you want to try some new preamp tubes in your amp to see what kind of tweaks you can make to the amp's tone, go right ahead.
Mesa/boogie amplifiers are made with a fixed bias that cannot be adjusted without digging into the amp and modifying resistor values in the bias power supply. They don't re-bias when you put new tubes in. You put the new tubes in, and go. That's it. I agree that at 3-4 hours a week for 13 years the power tubes presently in there are long overdue for replacement. Contact Mesa, Groove Tubes, or the tube vendor of your choice and let them know you have a Boogie you want to re-tube. Any tube vendor worth their salt should be able to match up a set of tubes that will bias properly in your amp.
The phase inverter does drive the power tubes, but is still a normal preamp tube. It handles preamp levels of power, which are a couple orders of magnitude less than the level of power the power amp puts out, so there shouldn't be a reason why the phase inverter would need replacing alongside the power tubes, IMO.
Preamp tubes do last a long time. Hell, I've got some 1960s RCA tubes in my Nomad, and they're doing just fine. If none of the tubes are acting microphonic, then the preamp is fine and shouldn't need replacing. If you want to try some new preamp tubes in your amp to see what kind of tweaks you can make to the amp's tone, go right ahead.
CaughtLikeFire
New member
Re: Will I notice new tube in my Mesa?
most amps have fixed bias, Mesa amps just don't have a bias adjustment pot (non-adjustable bias). it's really not so bad unless you're buying random tubes from vendors that don't rate and match their tubes well.
good call on the phase inverter - I forgot to mention it. a balanced Sovtek LPS is great in most Mesas - maybe a Ruby chinese 12AX7 since it's a combo and microphonics might be an issue.
most amps have fixed bias, Mesa amps just don't have a bias adjustment pot (non-adjustable bias). it's really not so bad unless you're buying random tubes from vendors that don't rate and match their tubes well.
good call on the phase inverter - I forgot to mention it. a balanced Sovtek LPS is great in most Mesas - maybe a Ruby chinese 12AX7 since it's a combo and microphonics might be an issue.
Ascension
Well-known member
Re: Will I notice new tube in my Mesa?
After 13 years those power tubes they have to be shot. You should notice a remarkable difference in tone with a power amp retube. Should really tighten up the bottom for sure.
I also am a big fan of Doug Preston over at Dougs Tubes. Great selection tests everything and stands behind the sale. It get's no better than Dougs.
http://www.dougstubes.com/
After 13 years those power tubes they have to be shot. You should notice a remarkable difference in tone with a power amp retube. Should really tighten up the bottom for sure.
I also am a big fan of Doug Preston over at Dougs Tubes. Great selection tests everything and stands behind the sale. It get's no better than Dougs.
http://www.dougstubes.com/
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Re: Will I notice new tube in my Mesa?
Thanks for the help guys! I think I will replace the whole set. I was considering using an SPAX7-A at the V1 input like MESA recommends. Would it be wise to use this "upgraded" tube at the phase inverter position? If so how do I know which pre-amp tube it is?
Thanks for the help guys! I think I will replace the whole set. I was considering using an SPAX7-A at the V1 input like MESA recommends. Would it be wise to use this "upgraded" tube at the phase inverter position? If so how do I know which pre-amp tube it is?
Re: Will I notice new tube in my Mesa?
The Mesa SPAX7-A is tube that Mesa found to have particularly low noise. V1, since it is the first tube in the signal chain through the amp is a great place for it, as the the less noise earlier in the signal chain, the less noise coming out of the amp overall.
@ACH91332, I realize that the phase inverter is considered part of the power amp, but since it is a 12AX7 (or other tube from the 12A*7 family) like every other tube in the preamp, receiving and outputting preamp levels of current and voltage, why would it take a beating any more than any of the tubes in the pre-amp?
The Mesa SPAX7-A is tube that Mesa found to have particularly low noise. V1, since it is the first tube in the signal chain through the amp is a great place for it, as the the less noise earlier in the signal chain, the less noise coming out of the amp overall.
@ACH91332, I realize that the phase inverter is considered part of the power amp, but since it is a 12AX7 (or other tube from the 12A*7 family) like every other tube in the preamp, receiving and outputting preamp levels of current and voltage, why would it take a beating any more than any of the tubes in the pre-amp?
