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Lost one channel of sound in new VAC Sigma 160i's?

Hi everyone, Just got it in today and set it up and as I changed from TT to CD, One side of sound went away. Anyone know may have happened? Thanks for any help.

I love music and the Audiophile world. I like most music, but Jazz & Rock and Roll is my Thrill. This Hobby may never end but might be the end of me, says my wife.

1,My Two Channel system is: CAT 100 Wat tube amp, With the CAT Legend pre, Esoteric X=03 CD player, "Sound of the Woods" TT and Sota Cosmos w/SME V arm w/Benz Glider cartridge. Speakers are Khorns and DC 10 Berlin Ref. w/Morrow & Cardas cables.

2.Home Theater Classe CAV 500 amp, Classe SSP 75 pre/processor,Oppo 105 Universal, Linn LP12Sondek w/Ekos arm w/Ortofon Jubilee. Cardas cables. B&W 802D & 805D w/Sony HD TV.
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zd542
5,339 posts
 
"I think it must be a bad tube. How can I find that out?"

Just swap the tubes. Tubes on the left channel go to the right, and the ones on the right go to the left. I think there's a good chance that you power tubes are OK. On my VAC amp, I have 2 power tubes per channel. If you remove a tube, the amp still works. If your amp is made the same way, you would have to have 2 bad tubes; both on the same channel.
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tradubois OP
3 posts
 
We are talking about the KT88's right? Also, could a 6550 be used in place of the 88's until I can talk to VAC and get more of their tubes? I have some new 6550 that I use in my CAT amp. Thanks, Tra
zd542
5,339 posts
 
Do the KT88's first, then the other tubes. You may be able to use the 6550's, but ask VAC first. To find out if you have bad tubes, just use the ones that are already in the amp.
philjolet's avatar
philjolet
2,306 posts
 
also, try swapping fuses, looking at them is not always enough
czarivey
5,946 posts
 
07-05-14: Philjolet
also, try swapping fuses, looking at them is not always enough
That is true, but checking them for continuity is much faster. I'd assume that tube amp owner should have at least simple DMM.
Checking bias from time to time can also signal about tube going bad.
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