TA-30 cuts out after 30 sec

Hi
I love the sound my TA-30 gives but I'm starting to lose confidence in it. After letting it warm up, I switch the standby of it runs for 30 sec or so and then cuts out for 10/20 sec. I have switched between voltages but it does the same on all output voltages. It hums when this happens and gives the impression that a relay is cutting it out as there is a click when it happens. Anybody have any ideas? I purchased it secondhand...does the five year guarantee also apply to Europe
TIA

Hertogjejan said:

Hi
I love the sound my TA-30 gives but I'm starting to lose confidence in it. After letting it warm up, I switch the standby of it runs for 30 sec or so and then cuts out for 10/20 sec. I have switched between voltages but it does the same on all output voltages. It hums when this happens and gives the impression that a relay is cutting it out as there is a click when it happens. Anybody have any ideas? I purchased it secondhand...does the five year guarantee also apply to Europe
TIA

Click to expand...

Stand by will only allow for the heaters to be active on all tubes. However, if the amp does what you say, especially with the hum and then cuts out, this would be signs of power tube failure. If you have not replaced the power tubes in your amp, that is most likely the cause. Not sure if there is an overload protection device on board in the TA series, if that is the case, that would explain what you are hearing as a result of excessive current through the power tubes. However, when a tube goes into redplate phase, it will sound very much like you described. You could power it up and watch the power tubes when you take the amp out of stand by. If you see a bright flash at the base, or if the plates in the tubes turn red, tubes are due to be replaced. Not sure on the warranty regarding location.

Hi
thanks for you reply, I have a tech who replaced the valves but I'm still having the same problem.The tech replaced them with Sovtek EL84 I know that boogie want you to use their valves should I go back and tell them I want MB's or is it a hard sell story from MB to use their products? What would cause the excessive current through the valves to occur, my power outlets are all earthed, we run at 220v here in the Netherlands.

hmm, did you have your tech do any other work on the amp?

I am uncertain if Mesa Boogie produces multi-voltage amps (supply different than 120VAC, perhaps European market is different). Is the input transformer compliant with the 220VAC? (is that also at 50Hz?) Most if not all MB are 120VAC /60Hz. Look at the back of the amp where the power cord insterts, does it indicate 120VAC? If it does, and if the TA-30 is completely stock, you probably need to have the input transformer replaced with one that is compliant with 220VAC.