Re: [Harp-L] Gibson GA-30 tube swap

[Russ Bradley <wbradley@xxxxxxxxxx>]

What year/model?
I've got a 1962 GA-30 Invader that I can turn up to 7 without feeding 
back as long as I'm on a grounded line.  If the line isn't grounded, 
I'll get this low frequency feedback.  Do you have a grounded power chord?
The tubes are defintiely non-standard, particularly the preamp tubes, 
but I'll have to check the schematic to tell you what they are.  It has 
one 12AU7, but I'm pretty sure that's driving the reverb.
If it's an older GA-30, I'm not sure I can be of help.
Regards,
Russ

Tim Dougherty wrote:

> Anybody have suggestions on harp-friendly tubes for this amp?  The 
> tubes seem to be non-standard.  In it's current configuration, it's 
> way to hot for a harp mic.  Additionally, is there an amp tech in the 
> Dallas/Ft. worth area you could recommend?
>
> Many thanks,
> Tim Dougherty
> www.HarpMicGaskets.com
>
>
>
>
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