OC75s with Black paint all chipped off?

[peps1]

Ordered 3 OC75s from eBay, but the guy had wrapped them in tape so the Black paint is all chipped off.

Dose this effect anything audio wise or just the resale value?

[anchovie]

I expect it makes as much sonic difference as snapping the Marshall logo off a JCM800 head.

[peps1]

Just wasn't sure if there was anything light sensitive in them.

[nick d]

   The old Mullard OC series had glass envelopes and were painted black to exclude light. If the paint got scratched off , they worked as phototransistors . They used to sell these unpainted as OCP series , and charge extra!

[peps1]

   The old Mullard OC series had glass envelopes and were painted black to exclude light. If the paint got scratched off , they worked as phototransistors . They used to sell these unpainted as OCP series , and charge extra!

Yep these are the old 60's Mullard glass envelope OC series......so should I re paint them?

[nick d]

                 I think so! ( unless you want the biasing to go up and down like a whores drawers !)

[Scruffie]

                 I think so! ( unless you want the biasing to go up and down like a whores drawers !)

Really? I've got a few that have flaked with age... gunna have to sort that out then by the sounds of it before I use them... I wonder if this has something to do with the use of metal jackets or pull over sleeves on some models then.

[nick d]

                Got it in one ! Any light getting in will make them work just like photo-transistors. OK if you wanted to make some sort of noiseless pot or something ?