5:50 Clean Channel Master Volume / Breakup ?

[express50express]

It could be my ears (and maybe I am starting to loose hearing), but I feel like the master volume on the 5:50 isn't as sensitive as it used to be. I also sounds that with humbuckers I get a slight breakup, which i'm not sure i had before at the setting I have below.

When I play with my band, I only use clean channel as my base. My gain is around 10 o'clock and my master is close to 11 o'clock. Should i expect a slight breakup with these settings? I have changed tubes and I get the same results.

Curious what other are experiencing for band practice master volume settings and clean channel breakup.



Thanks

 

[Newysurfer]

It could be my ears (and maybe I am starting to loose hearing), but I feel like the master volume on the 5:50 isn't as sensitive as it used to be. I also sounds that with humbuckers I get a slight breakup, which i'm not sure i had before at the setting I have below.

When I play with my band, I only use clean channel as my base. My gain is around 10 o'clock and my master is close to 11 o'clock. Should i expect a slight breakup with these settings? I have changed tubes and I get the same results.

Curious what other are experiencing for band practice master volume settings and clean channel breakup.

Thanks

No
On clean channel with SG on mine at 50w it doesn't start slightly breaking up till I push the gain dial to over 2 o'clock with master around 12 o'clock.
Can depend on which tubes you're using and what you mean exactly by "slight breakup". Try to test another 5:50 somewhere to compare

 

[express50express]

It could be my ears (and maybe I am starting to loose hearing), but I feel like the master volume on the 5:50 isn't as sensitive as it used to be. I also sounds that with humbuckers I get a slight breakup, which i'm not sure i had before at the setting I have below.

When I play with my band, I only use clean channel as my base. My gain is around 10 o'clock and my master is close to 11 o'clock. Should i expect a slight breakup with these settings? I have changed tubes and I get the same results.

Curious what other are experiencing for band practice master volume settings and clean channel breakup.

Thanks

No
On clean channel with SG on mine at 50w it doesn't start slightly breaking up till I push the gain dial to over 2 o'clock with master around 12 o'clock.
Can depend on which tubes you're using and what you mean exactly by "slight breakup". Try to test another 5:50 somewhere to compare

Thanks for the reply. I called mesa and they suggested to swap the power tubes with new ones (i'm using the mesa tubes), which i did. Results are the same. I'm wondering if i should change the pre-amp tubes next. The other thing i want to mention is that i'm running my 5:50 head into a 2 x 12 cabinet wired as parrallel with 2 x black shadow speakers. I'm using the 4ohm jack since it's a 4ohm. It's matched correctly.

 

[sax4blues]

Hard to compare everyones expression of slight break up. But with gain 10 and master 11 this should be pretty loud and still clean, even with humbuckers. I do get some warm purr at gain levels above 3, but never anything I would describe as breakup.

 

[Newysurfer]

It could be my ears (and maybe I am starting to loose hearing), but I feel like the master volume on the 5:50 isn't as sensitive as it used to be. I also sounds that with humbuckers I get a slight breakup, which i'm not sure i had before at the setting I have below.

When I play with my band, I only use clean channel as my base. My gain is around 10 o'clock and my master is close to 11 o'clock. Should i expect a slight breakup with these settings? I have changed tubes and I get the same results.

Curious what other are experiencing for band practice master volume settings and clean channel breakup.

Thanks

No
On clean channel with SG on mine at 50w it doesn't start slightly breaking up till I push the gain dial to over 2 o'clock with master around 12 o'clock.
Can depend on which tubes you're using and what you mean exactly by "slight breakup". Try to test another 5:50 somewhere to compare

Thanks for the reply. I called mesa and they suggested to swap the power tubes with new ones (i'm using the mesa tubes), which i did. Results are the same. I'm wondering if i should change the pre-amp tubes next. The other thing i want to mention is that i'm running my 5:50 head into a 2 x 12 cabinet wired as parrallel with 2 x black shadow speakers. I'm using the 4ohm jack since it's a 4ohm. It's matched correctly.

Ahh your 1st post said you changed tubes so I assumed that was all of em.
Then 2nd post says you still have the original pre-amp tubes in.
It's most likely just a routine tube issue.
Change em all and i recommend you not use Mesa tubes either.
They're expensive and very ordinary imo :mrgreen:

 

[express50express]

Thanks, I really hope that is it. The amp is 1 year old, but it is a floor model. I called Mesa and they said to change the power tubes first, and then go from there. They said the pre-amp tunes never have issues (strange). I will try all new pre-amp tubes. I won't argue that the Mesa tubes are not that special, but I think I will buy them for now, as I really want to get my amp back to normal first, and then experiment. I don't want to add any more variables to the issue.

The other significant issue I noticed last night was a complete lack of volume or output from the amp. This is true in both 5w and 50w mode. It still sounds good, but it just sounds dead compared to what I'm used to hearing. With a Les Paul, I used to be able to get great harmonics all day long and some nice controllable feedback. Right now, I get neither! I also push this thing pretty hard with a Pair of Tubescreamers when I really need it.

I remember switching between both wattage modes before and the output level was night and day. Now the output is less dramatic between the two wattage modes. Also, as a quick test in the 5w mode with gain at 3 o'clock and the master almost dimed, it is still at bedroom level to my ears. I remember before, even in the 5w mode with the master at noon, it was plenty loud. Not the case now. Over the last months I have been switching a lot between 4ohm and 8ohm speaker jacks to try different speaker / cabinet combinations and I'm worried I may have damaged the output transformer. I've been pretty careful when switch jacks to both never have a mismatch and either keep the amp in Standby or volume off on the guitar so there is no load on the amp when I switch. Again, I may be just paranoid about the OT.

I'm really crossing my fingers that what I'm describing is a sympont of dead pre-amp tubes and not something else!

Thanks

 

[Krek13]

The other significant issue I noticed last night was a complete lack of volume or output from the amp.

it's the tube(s) 99% sure
if you dont have the money to buy a whole set of ecc83s you can buy only one and then swap one tube at a time to find out which one is faulty...

 

[robertkoa]

You also might try a JJ 803s preamp tube in V1.

They have a very large Plate and spiral filament for low noise and seem to have a little more headroom

on clean channels and a wider sweet spot on gain channels, a little less aggressive more clear on distortion.

This depends on the Circuit etc. but if it works it's a noticeable difference and only 15 $ to try.

 

[express50express]

You also might try a JJ 803s preamp tube in V1.

They have a very large Plate and spiral filament for low noise and seem to have a little more headroom

on clean channels and a wider sweet spot on gain channels, a little less aggressive more clear on distortion.

This depends on the Circuit etc. but if it works it's a noticeable difference and only 15 $ to try.

Good news to report... My tone is back! When I swapped out the 2nd preamp tube "V2", everything was back to normal. According to the owners manual V2 is 1st Gain Stage.

I now have full volume capability and plenty of clean headroom.

Thanks for the tip on the JJ 803s preamp tube. I will give that try. According to the owners manual V1 is the 2nd Gain Stage for Channel 1 and also the 3rd Gain Stage for Channel 2.

I ended up replacing all 5 preamp tubes anyways :? oh well. The amp was a floor model a year ago and i haven't replaced a tube until now, so I didn't mind that much.

Thank you all for the replies and assistance.

 

[Newysurfer]

Thanks, I really hope that is it. The amp is 1 year old, but it is a floor model. I called Mesa and they said to change the power tubes first, and then go from there. They said the pre-amp tunes never have issues (strange).
Thanks

hahahaha - preamp tubes never have issues huh. Who did you chat with - the receptionist hehe
Preamp tubes are THE first thing that fail on tube amps, followed by fuses, power tubes and transformers :mrgreen:

 

[express50express]

Thanks, I really hope that is it. The amp is 1 year old, but it is a floor model. I called Mesa and they said to change the power tubes first, and then go from there. They said the pre-amp tunes never have issues (strange).
Thanks

hahahaha - preamp tubes never have issues huh. Who did you chat with - the receptionist hehe
Preamp tubes are THE first thing that fail on tube amps, followed by fuses, power tubes and transformers :mrgreen:

I got more help from you and other forum members versus calling Mesa!

 

[Newysurfer]

Thanks, I really hope that is it. The amp is 1 year old, but it is a floor model. I called Mesa and they said to change the power tubes first, and then go from there. They said the pre-amp tunes never have issues (strange).
Thanks

hahahaha - preamp tubes never have issues huh. Who did you chat with - the receptionist hehe
Preamp tubes are THE first thing that fail on tube amps, followed by fuses, power tubes and transformers :mrgreen:

I got more help from you and other forum members versus calling Mesa!

hehe maybe Mesa told you to replace the power tubes first cause they cost more to buy than the preamp tubes.
They charge a ridiculous $70 per power tube in Australia for their el cheapo chinese one's

 

[express50express]

Guitar Center sells a pair of 6L6 Mesa Power Tubes for $42 bucks. Each preamp tube is $18. I noticed Groove Tubes were even more. Not sure why.

 

[express50express]

I have another update to my Mesa Boogie Express 5:50 low output/breakup issue. As stated earlier, I replaced all output and preamp tubes and the tone was great. I then had a rehearsal last week and the tone was great also, until after about 3 hours, it didn’t sound as clean. I starting checking my channels and pedals, and my amp was on what should have been super clean. I noticed the symptoms coming back.

My amp was plugged into a 2 x 12 THD cabinet using the 8ohm jack on the amp. Now, I really thought my cabinet was 2 x 16ohm speakers wired in parallel. Unfortunately, I was dead wrong! They are 2 x 8ohm speakers wired in parallel, which is a 4ohm load. I was connecting into the 8ohm amp output jack, which created a mis-match, during 3 hours of playing, at a decent level.

I got home and started to troubleshoot, and I was back where I started a few weeks ago. At this point, I’m thinking I need to replace the tubes again and make sure the ohms match. I’m guessing the mismatch has caused to much load on the tubes, causing them to wear much much quicker than normal. Hoping that is it, and no other damage.

Back a few weeks ago was the first time the tubes went dead (replacing them fixed it) I think it all started when I played with the mismatched cabinet. I’m hoping this is still the case, and I can just replace tubes and go from my 4ohm output jack to the 4ohm input jack on the cabinet, and be fine going forward.

Right now the volume is good, just some early break up at low volumes. Bottom end seems a little weak. Overall output power is fine. Wondering if the power tubes should be replaced again.

Thoughts?

 

[Krek13]

it is possible that tubes got worn out in a few hours...what you described is a serious mismatch and you can be happy if the output transformer didn't get damaged...I would take the amp to a tech to prevent further damage and to make sure everything is fine...be more cautious in the future...

 

[express50express]

it is possible that tubes got worn out in a few hours...what you described is a serious mismatch and you can be happy if the output transformer didn't get damaged...I would take the amp to a tech to prevent further damage and to make sure everything is fine...be more cautious in the future...

Thanks, I replaced the power tubes and the tone improved drastically. I replaced V2 preamp tube and I all improved things. I'm wondering if I should keep on going and replace the remaining 4 x preamp tubes. I'm also going to take it to a take to have the OT tested.

Thanks