JCM 800 - Large volume loss on low sensitivity input

[Disco Cat]

I've lost a lot of volume & gain on the low sensitivity input, though the high sensitivity input is normal. Can someone tell if it's likely a tube issue, and maybe pinpoint me to whether it'd be preamp, and which position? It'd be cools.

[New Trail]

 

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Disco Cat wrote:

 

 

I've lost a lot of volume & gain on the low sensitivity input, though the high sensitivity input is normal. Can someone tell if it's likely a tube issue, and maybe pinpoint me to whether it'd be preamp, and which position? It'd be cools.

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My JCM800 (4010 Combo) is exactly like that....always has been.  I thought that was the norm?!?

[Disco Cat]

It's normal to have less, but I mean it's dropped a lot from its normal level. It's a lot less than half the volume of the high gain input, and I can't get distortion out of it with preamp cranked to the max, and both a boost and overdrive pedal out front.