My RK II just died??

[disassembled]

Tubes can still function cracked. If the roadkings are runnings the 12AX7's to the point where they are cracking this is a serious issue and is a serious design flaw. I would have to be in serious doubt to believe that Mesa would design an amp that could self destruct a preamp tube. Pre tubes do not need fans as they are very rugged tubes; even the cheapest brands of tubes.

Boogiebabies,

What kind of voltages are the pre tubes running at? The triaxis runs at 420 volts or so for the 12Ax7's. The 20/20 runs at 150v for the input and 260v for the PI. Am I correct in this info? It's what is written on the schematics.

 

[xscottx9]

just had another one break in my fingers pulling it out .. thats 3 pre amp tubes within 4 days of owing the amp.

I have never had a pre amp tube break in my fingers .. so its not like I am man handling them ..

 

[CudBucket]

My RKII arrived in exact same condition. It's not a problem with the amp but with the tubes. I found V2 cracked and white. I called Mesa and they sent 4 replacements. Problem solved. Apparently you still have some tube problems if you don't have channel 2.

 

[Aart]

get a few russian or european tubes(Phillips eindhoven rules), that will solve your problems!

 

[disassembled]

I would ask Mesa to send all new pre tubes before having it looked at.

 

[alpepiman]

Replace the fuse(s). How do you know the fuse is good?

 

[disassembled]

Replace the fuse(s). How do you know the fuse is good?

If the fuse was bad either all or part of the amp would not have power depending on which fuse is bad.

 

[Platypus]

Replace the fuse(s). How do you know the fuse is good?

Fuses are binary.. they either work or they don't. If the fuse was bad it means there was a short in the circuit and it blew to protect the amp... at which point the amp wouldn't even power on.

 

[alpepiman]

Not so.

I my Marshall has 2 fuses I believe. One of the fuses blew, the amp powered on, lights and all yet no sound came out. Same as this situation. The fuse appeared to be fine, but it had blown.

 

[Platypus]

Not so.

I my Marshall has 2 fuses I believe. One of the fuses blew, the amp powered on, lights and all yet no sound came out. Same as this situation. The fuse appeared to be fine, but it had blown.

Interesting, to the best of my knowledge Mesa amps have one fuse and it behaves like I described earlier.

 

[disassembled]

Not so.

I my Marshall has 2 fuses I believe. One of the fuses blew, the amp powered on, lights and all yet no sound came out. Same as this situation. The fuse appeared to be fine, but it had blown.

Right, that was the High Voltage fuse for the power tubes. The user said his amp works fine except for channel 2 having a fizzy quality. How would a fizzy quality be related to fuses?

 

[xscottx9]

Called mesa, they are sending out new pre amp tubes. Replaced all the Mesa Tubes with randomn 12AX7's I had laying around and the amp works fine now .. its tone has changed a little, i think I prefered the mesa tubes. Tung Sol, Chinese, and some JJ's ..

I wonder how many problem tubes are out there, with mesa's website, and catalog being so TUBE quality assured, I cant believe this happaned.

 

[disassembled]

Called mesa, they are sending out new pre amp tubes. Replaced all the Mesa Tubes with randomn 12AX7's I had laying around and the amp works fine now .. its tone has changed a little, i think I prefered the mesa tubes. Tung Sol, Chinese, and some JJ's ..

I wonder how many problem tubes are out there, with mesa's website, and catalog being so TUBE quality assured, I cant believe this happaned.

Sounds good. I think you just got some damaged tubes so hopefully the next set won't be bad.

 

[Barry]

Called mesa, they are sending out new pre amp tubes. Replaced all the Mesa Tubes with randomn 12AX7's I had laying around and the amp works fine now .. its tone has changed a little, i think I prefered the mesa tubes. Tung Sol, Chinese, and some JJ's ..

I wonder how many problem tubes are out there, with mesa's website, and catalog being so TUBE quality assured, I cant believe this happaned.

Glad to hear things are better now .

 

[alpepiman]

Not so.

I my Marshall has 2 fuses I believe. One of the fuses blew, the amp powered on, lights and all yet no sound came out. Same as this situation. The fuse appeared to be fine, but it had blown.

Right, that was the High Voltage fuse for the power tubes. The user said his amp works fine except for channel 2 having a fizzy quality. How would a fizzy quality be related to fuses?

I was referring to this, which clearly stated the same problem I mentioned before.

I played it Saturday night, everything worked fine .. turned it off.

Turned it on today, .. and nothing. ALl the tubes are lit up, the Fuse is intact .. have not changed anything in the back .. no knobs turned. Tried differant cab, and guitar .. ran setup through another amp for cable check and all worked ..

all lights are on, tried with and without pedalboard, fan on, cab selections, and loop selections all in the right spot.

just ZERO sound?

any ideas?

 

[disassembled]

Not so.

I my Marshall has 2 fuses I believe. One of the fuses blew, the amp powered on, lights and all yet no sound came out. Same as this situation. The fuse appeared to be fine, but it had blown.

Right, that was the High Voltage fuse for the power tubes. The user said his amp works fine except for channel 2 having a fizzy quality. How would a fizzy quality be related to fuses?

I was referring to this, which clearly stated the same problem I mentioned before.

I played it Saturday night, everything worked fine .. turned it off.

Turned it on today, .. and nothing. ALl the tubes are lit up, the Fuse is intact .. have not changed anything in the back .. no knobs turned. Tried differant cab, and guitar .. ran setup through another amp for cable check and all worked ..

all lights are on, tried with and without pedalboard, fan on, cab selections, and loop selections all in the right spot.

just ZERO sound?

any ideas?

Hey I am trying not to be an *** but did you even read the whole thread? I assume not because later he states the amps works and the problem was a blown tube.

 

[JamesD]

Glad to hear that things are getting solved!!! Goodluck!

 

[CudBucket]

Called mesa, they are sending out new pre amp tubes. Replaced all the Mesa Tubes with randomn 12AX7's I had laying around and the amp works fine now .. its tone has changed a little, i think I prefered the mesa tubes. Tung Sol, Chinese, and some JJ's ..

I wonder how many problem tubes are out there, with mesa's website, and catalog being so TUBE quality assured, I cant believe this happaned.

This is not a Mesa issue. Any tube amp manufacturer deals with tubes breaking in transportation or shortly after.

 

[CudBucket]

Not so.

I my Marshall has 2 fuses I believe. One of the fuses blew, the amp powered on, lights and all yet no sound came out. Same as this situation. The fuse appeared to be fine, but it had blown.

Yeah well you had 2 fuses and one blew. And the amp didn't work. That's because fuses either work or they don't. Mesa's have one fuse so when they blow, nothing works at all.

 

[kingster911]

I had the same problem.

The V1 runs normally and gets hot. When you shut it down the glass on the new Chinese 12AX7 is too thin and it cracks. Mine cracked in half like yours. After a new pre, she worked just fine. Now, I still use the Mesa Chinese 12AX7 and blew another one so now I let it coold down for ten minutes before I shut down. If your an opening act, you wont have time to do this. I remember the days where the stage manager would yell" If you don't have your sh!t off in 5 minutes, were throwing it out the back door".

:::I had a similar problem as this with Ch. 2 of my RKII. It's not completely blown, but just Ch. 2 is buzzy. It breaks up quickly and weakly. Probably the same as what's been mentioned. I've heard crackles of the tubes in the back when I turn the amp off. Is this the problem? I've heard you're sort-of supposed to leave the amp on for awhile, which if not I could understand so it could warm up. Answers, questions?