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OLDER DECWARE GEAR SUPPORT >> TORII MK III >> arcing in 5u4g
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Message started by SteveC on 09/18/11 at 11:58:57

Title: arcing in 5u4g
Post by SteveC on 09/18/11 at 11:58:57

I started noticing arcing in the left rectifier tube on Torii mkiiii. Doesn't seem to affect sound. it happens only during power-on. Swapped the left and right tubes and the arcing moved to the right with the suspect tube. Switched out the bad one with the one from my se84c and no more arcing. So... Is that tube defective? Why would it fail so soon ? Because it failed so soon, do I have to worry some root problem with the amp? Is it safe or ok to continue using that tube? Anyone else seen this? Symptom: exactly when the larger voltage regulator starts glowing, blue spark jumps from the bottom of the 5u4g to the top plate. Sometimes glowing embers fall inside after the spark. Hot or cold tube makes no difference.

Title: Re: arcing in 5u4g
Post by Lon on 09/18/11 at 12:48:20

This is a tube beginning to fail is my estimation. If it's a stock Ruby tube I've never been impressed with these and quality control from the manufacturer may be an issue. I would replace that or the pair, unfortunately I think that is the safest option.

Title: Re: arcing in 5u4g
Post by Rivieraranch on 09/18/11 at 13:08:02

Give that tube the deep six before it could do some damage.

Title: Re: arcing in 5u4g
Post by will on 09/18/11 at 15:17:54

That tube sounds on the way out in a sort of big way. I had a rectifier go once without apparent arching and it blew the fuse at the IEC inlet immediately. Then I looked in the manual for fuse info, and Steve mentioned that rectifiers can mysteriously go at any time and blow the fuse. Could be shipping shock, a voltage spike....I don't recall how I figured out it was one of the rectifiers, but I did. So I stuck in a replacement pair I had, and no problems. If the tube is relatively new, I bet Decware will replace it.

Title: Re: arcing in 5u4g
Post by SteveC on 10/15/11 at 02:24:08

update:

Haven't bought tubes yet, but I did realize that there's no arcing when powering up dead cold. (torii off for many hours)

The only time I see the arcing is when I turn off the torii, then back on again.

I first did this to hear only one channel for some reason.

Anyway, will get tubes, but I just don't power cycle the torii anymore.