5D3 Input

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RWood
Posts: 254
Joined: Sun Jul 07, 2013 7:56 pm

5D3 Input

Post by RWood »

When adjusting guitar volume from 1 to 8 it works but only slightly, and 9 to 10 I get 80% increase in gain. Different guitar yields the same result. Both guitars work correctly on all other amps.
The tone is amazing, especially when pushed by Tube Screamer set as clean boost. The problem is that I don't have much control to back off to clean up guitar.
Both interactive volumes of the amp work fine, just the guitar volume pot acts wonkey with this amp only.
I don't really care if I can fix it or not, as I usually run guitar volume wide open anyway, I'm just curious about what's going on.
Input is 1m to ground with 33k to grids.
If it don't get hot and glow, I don't want it !
pdf64
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Location: Staffordshire, UK
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Re: 5D3 Input

Post by pdf64 »

It may be oscillating.
Does adding grid stoppers at the tube socket terminals resolve it? eg 10k at each pre-amp grid, 1k5 on the power tube control grids.
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RWood
Posts: 254
Joined: Sun Jul 07, 2013 7:56 pm

Re: 5D3 Input

Post by RWood »

1M to ground was cold joint. Why it resulted in that behavior is beyond me but now it works fine!?
If it don't get hot and glow, I don't want it !
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