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Post by gninnam on Dec 17, 2021 22:16:16 GMT
Listening to some tunes tonight and noticed that the sound had slewed to the right using the SP-10...............
Switched to Roon and the same thing.
The valve amp can be run in Triode (normal setting) or Ultra Linear so switched to UL. Now playing perfectly.
Thoughts??
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Bigman80
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Post by Bigman80 on Dec 17, 2021 23:00:53 GMT
Listening to some tunes tonight and noticed that the sound had slewed to the right using the SP-10............... Switched to Roon and the same thing. The valve amp can be run in Triode (normal setting) or Ultra Linear so switched to UL. Now playing perfectly. Thoughts?? Biasing issue? |
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Post by gninnam on Dec 17, 2021 23:08:05 GMT
Its supposed to be self biasing.
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Post by firebottle on Dec 18, 2021 8:51:53 GMT
Could be a less than optimum contact on the switch.
Easy to try by just switching back to triode mode.
Only guessing but otherwise could be a valve losing a bit of gain (?) and being boosted back up when in pentode/UL mode.
Interesting one.
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Post by gninnam on Dec 19, 2021 10:10:28 GMT
Set to Triode this morning and using Roon/Tidal/PI and sounding perfick. Do love valve amps first thing in the morning. Listening to some dance music and it is certainly making my head and feet move  |
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Post by macca on Dec 19, 2021 10:16:54 GMT
you must have one of those DACs with the 'foot tapping' circuitry in it then  |
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Post by gninnam on Dec 19, 2021 10:18:08 GMT
you must have one of those DACs with the 'foot tapping' circuitry in it then  I paid extra for that!! |
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Post by gninnam on Dec 24, 2021 11:08:00 GMT
Due to my kids being home for Christmas (well, no longer kids as 25 and 24...) last night I had a listening session with headphones so all good.
This morning, before we head out I thought I would put an album on and guess what, with the amp being in triode mode only getting music from the right channel.
Plugged headphones in the preamp and both channels. Checked all the cable from the preamp to the power amp plus the speaker cables and all good.
Turned the power amp off, switched to ultra and powered back on - now have stereo again!
May remove and reseat the valves to see if that makes a difference in triode mode or could it be that one of the power valves is on its way out?
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Post by gninnam on Dec 24, 2021 11:27:38 GMT
Second side of the album and the left channel disappeared.
Powered off then back on and left channel back.
Think I will contact Guy and probably ship it to him so he can have a look.
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Post by nuff on Dec 24, 2021 16:04:50 GMT
That’s the exact problem I had. I switched to ultra linear and it played for 10 mins or so, the left Chanel started crackling & popping and dropping in and out. Also as I jumped up to switch it off one of the left valves was flickering.
I replaced the 4 6550’s (with KT88’s) and now all is working fine again. I’m sure it’s just the valve or valves, but then I’m no expert.
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Post by nuff on Dec 24, 2021 17:05:49 GMT
Just a thought. You could swap the left and right 6550’s to see if it transfers to the right Chanel. If so you know it’s the valves.
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Post by gninnam on Dec 26, 2021 14:34:24 GMT
Update folks (oh and I hope you all had a great Christmas  I had swapped the 6550 pairs over and the issue remained on the left side. Spoke to Guy who suggested first using Servisol on the volume pot first. If that fails then swap the driver valves around etc. If all that fails then probably a capacitor or something which will mean shipping it back to him for the proper once over. Used it on Christmas eve for around 3 hours with no issues......... |
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Bigman80
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Post by Bigman80 on Dec 26, 2021 14:45:09 GMT
Update folks (oh and I hope you all had a great Christmas I had swapped the 6550 pairs over and the issue remained on the left side. Spoke to Guy who suggested first using Servisol on the volume pot first. If that fails then swap the driver valves around etc. If all that fails then probably a capacitor or something which will mean shipping it back to him for the proper once over. Used it on Christmas eve for around 3 hours with no issues......... That's good news. |
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