I wonder if someone can advise me on the following...
My PH-1 makes a kind of 'thump' sound when switched on and off, not too loud as to make in unusable but a bit anoying all the same. Various bits of surfing have led me to believe that this could be the result of some trimpot twiddling by a previous owner. If this is the case can it be rectified and if so how? Would the details be in the service guide should such a document exist? I don't have scope and source but have a friend who has.
I was also wondering whether it would be worth changing out any of the components to reduce noise levels, metal film caps and maybe even different chips. Any views on this?
If anyone can help me with a shematic and / or service guide please get in touch. I have searched the net a bit for downloads but most references lead back to posts here.
I've just been through an exercise of trying to fix the "mild bump" noise when you switch on a PH-1R. Spent hours with no luck, so finally arranged to borrow a couple of other PH-1R's and checked them out side-by-side. They ALL do it. Problem solved - it's a "feature"
Trimpot fiddling in a PH-1 will affect the phasing - it shouldn't affect the "bump' sound. If it phases properly and sounds good to you ear, then the trim-pot is probably OK. Really will take a scope to reset if it's not right - the service notes are pretty good.
I'd suggest just leaving the components. Closer to completely standard you can keep it, the more it's worth...
PH-1 help needed
Posted - 04/20/2009 : 12:03:04
