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Darkglass Microtubes 500 V2 randomly shuts down

There are many possible causes IF the fan is not running when this happens, that's one (of many) possible causes. I'm not sure why a PTC would be the first or even likely cause, and that assumes that either the amplifier or SMPS actually uses one.

If the amp shuts down after time with no load attached, it's certainly the amp and the manufacturer should help you get this resolved.

Yep - many possibilities and I'm guessing. The amp will be replaced or repaired by the vendor. At least the fault is replicable with nothing connected, so hopefully it won't be returning with 'no fault found'
 
Yep - many possibilities and I'm guessing. The amp will be replaced or repaired by the vendor. At least the fault is replicable with nothing connected, so hopefully it won't be returning with 'no fault found'

I don’t think they can return it with any fault found. I’ve got 30 days to return it so that’s not an issue. I’m going to tell them to plug it in and power it up, and then just leave it. They’ll see it doesn’t work.
 
Just hit this same problem (random shut down after approx 3 hours)., I'm running passive P bass so input should not be the cause. Drive and Level and Master all at noon ..and running into an 8ohm 2x10 cab.
Strage part is that I've played this way many times and not had this issue before., just last night. I turned off for a minute and back on and it came back. I ran it for another half hour without issue.
Was there any up date on the issue., did a replacement head act the same ? appreiate any info - thx
 
Just hit this same problem (random shut down after approx 3 hours)., I'm running passive P bass so input should not be the cause. Drive and Level and Master all at noon ..and running into an 8ohm 2x10 cab.
Strage part is that I've played this way many times and not had this issue before., just last night. I turned off for a minute and back on and it came back. I ran it for another half hour without issue.
Was there any up date on the issue., did a replacement head act the same ? appreiate any info - thx

Sorry to hear you have the same issue. Mine turned out to be an issue where the fan wouldn’t come on and it was overheating. They just replaced the whole unit.
 
I found one other thread on TB (and the internet) about this issue. I bought a Darkglass Microtubes 500 V2 earlier this week, and it sounds great. I'm also loving how small it is, and I'm planning some nice things to do with it.

But, more than once I've just been playing and the power appears to have cut to it. I've then tried it with multiple different cables and plug sockets and found it to still be powered down. So, it has to be something within the amp.

I think I may have noticed a pattern, which I will test over the next couple of days. It has happened when the bass EQ channel on my bass has been turned to max. I think I also noticed that the Active/Passive switch was set to Passive whilst I'm using an active bass. I wonder if this is the key to it.

Is that a realistic cause? I have messaged @Darkglass but no doubt he/they are very busy!

Obviously I'm likely to return it for a replacement, but I do wonder if I'm causing it; whether it needs the reduction that the Active/Passive switch generates, and that perhaps I've been overloading it.

Any thoughts would be much appreciated.

dirtychinchilla

Edit: ok that theory was bogus. I just played for about 20 minutes with the switch set to Active and it shut down again.
Broo this just happened to me in a middle of a recording session at the music studio.... was soo pissed off . we lost the money and time trying to figure what was causing it.... i think from what i read it is the Fan its not working as well on mine but im just guessing....already contacted Darkglass but is it me or they have a very terrible custome service...
 
Broo this just happened to me in a middle of a recording session at the music studio.... was soo pissed off . we lost the money and time trying to figure what was causing it.... i think from what i read it is the Fan its not working as well on mine but im just guessing....already contacted Darkglass but is it me or they have a very terrible custome service...

That's very annoying. Good luck on getting it sorted out. I was able just to return mine to where I bought it fortunately - hope yours is still in warranty.
 
I don't believe it is anything anyone is doing that is causing the shut down., its the design and/or build of the head., I did extensive tests in different environments and conditions and while there was differences in exactly when the head shut down., it always shut down, everytime. Sometimes after +2 hours but sometimes after just a few mins (so not soley 'heat' related either).

Mine went back to Thomann about 4 weeks ago, for "repair" (they didn't offer a replacement). I don't have any update from them yet. I'm hoping for a 'real' explanation of what was wrong and what they fixed., or else a refund. Anything less than this means I can't ever trust the head enought to actually use it., nor could I ever sell it on (I wouldn't sell something as being in 'working order' if I wasn't confident it actually was)
 
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UPDATE; Thomann repaired and returned my MT 500 v2 ...9 weeks later. They said they replaced the "power unit". I don't personally know exactly what that means but, now, the fan is simply on all the time. After a 4 hour rehearsal session, the head was still stone cold. That is a massive difference than before where the fan only kicked in after about 40 mins use and then only for a few minutes at a time. Of course, the fan being on all the time means the head is no longer suitable for home practice (as it is a very loud fan)., even for recording, it would be DI only or some arrangement to have the head in a different room to any mic'ed cab - so gig/rehearsal use only.
 
UPDATE; Thomann repaired and returned my MT 500 v2 ...9 weeks later. They said they replaced the "power unit". I don't personally know exactly what that means but, now, the fan is simply on all the time. After a 4 hour rehearsal session, the head was still stone cold. That is a massive difference than before where the fan only kicked in after about 40 mins use and then only for a few minutes at a time. Of course, the fan being on all the time means the head is no longer suitable for home practice (as it is a very loud fan)., even for recording, it would be DI only or some arrangement to have the head in a different room to any mic'ed cab - so gig/rehearsal use only.

Excellent news. Sounds like they’re replacing a few power units then
 
Update: got mine took around 2 weeks to settle and get the new amp head and send out the defective one. So yea it was the fan if you see through the window where the fan supposed to move it has to be clear without a metal bracket inside that causes also heat problems.


Told darkglass that there's many units and people experiencing the same issue. Hooe this helps

(See the picture of the new unit ) clear and working fan
 

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Update: got mine took around 2 weeks to settle and get the new amp head and send out the defective one. So yea it was the fan if you see through the window where the fan supposed to move it has to be clear without a metal bracket inside that causes also heat problems.


Told darkglass that there's many units and people experiencing the same issue. Hooe this helps

(See the picture of the new unit ) clear and working fan
So they just removed the bracket inside to allow more air flow or did they also replace the fan?