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PaoloJM · 06-29-2009, 04:22 PM

The DSL 100 has a cap installed between the plate and screen of the fourth power valve. This helps to reduce the hum that's inherent in the design (I'm afraid to say anything insulting here!!). These are rated quite low at 500V and are prone to failure, causing much hum. I've seen a few go and replace them with a 2kV, 22p cap.

I'm not sure about the DSL 50 has them as I haven't worked on one, but it would be worth checking if that might be the problem.

06-29-2009, 04:22 PM	#24 (permalink)
PaoloJM Senior Member Join Date: Jun 2008 Location: Cork, Ireland Posts: 534	Re: Humming & vibrating DSL50 head The DSL 100 has a cap installed between the plate and screen of the fourth power valve. This helps to reduce the hum that's inherent in the design (I'm afraid to say anything insulting here!!). These are rated quite low at 500V and are prone to failure, causing much hum. I've seen a few go and replace them with a 2kV, 22p cap. I'm not sure about the DSL 50 has them as I haven't worked on one, but it would be worth checking if that might be the problem. __________________ www.youtube.com/paolojm