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Topic: Power tube matching question |
Tommy Boswell
From:
Virginia, USA
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Posted 19 Oct 2017 2:28 am |
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Here's a question for tube amp technicians. My Carvin TS100 is an all-tube stereo power amp, 50 watts per side, and 100 watts bridged. When shopping for new tubes, I know I need at least a matched pair for each side of the amp. But what about for bridge mode, does it need to be a matched quad? Or do the two matched pairs continue to work independently, so that matching all four might not be a requirement?
Reason for asking, I was going to sell the EL34s that came with the amp as a matched quad. But now I'm 2nd guessing myself as to whether it's a matched quad or two matched pairs. Took the listing down for now. |
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J Fletcher
From:
London,Ont,Canada
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Posted 19 Oct 2017 7:15 am
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| Not familiar with the Carvin TS100 but you could just buy a matched quad and be done with it. |
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ajm
From:
Los Angeles
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Posted 19 Oct 2017 7:58 am
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It sounds like you really have two issues or questions.
1) Do the tubes need to be a matched Quad, or will two matched pairs be OK?
2) Are the EL34s that you want to sell that came with the amp matched pairs or a matched Quad>
If you have access to a bias meter or similar method you could check the tubes that way.
I can't say for sure, but it sounds like from reading the manual that they want you to use a matched QUAD only. They may do this for simplicity's sake or to limit the possibility of damage or whatever.
FWIW, a couple of snippets from the manual...........
The TS100 can be set up to use either EL34’s or 5881’s (6L6GC) in each channel. If different tube type are used in each channel, the amp should only be used in STEREO mode.
Inside the amplifier, on the component side of the power tube printed circuit card, are switches to select the tube type for each channel. Above those switches are markings that indicate the different tube types. Bias potentiometers are also near those switches for fine-tuning. Each side of the amplifier must be biased with ALL four power tubes installed. |
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Tommy Boswell
From:
Virginia, USA
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Posted 19 Oct 2017 8:46 am
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| J Fletcher wrote: |
| Not familiar with the Carvin TS100 but you could just buy a matched quad and be done with it. |
That's what I did. Just wanted to know what the factory originals are likely to be. |
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Tommy Boswell
From:
Virginia, USA
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Posted 19 Oct 2017 8:49 am
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| Thanks ajm. The manual's biasing instructions are very good. Process is a little tedious, but I got through it when I made a switch from EL34s to 6L6s. |
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