I have obtained a scruffy-looking pair of QUAD II amps, S/N 30773 and 30679.
They are going to need a lot of cosmetic work, but all the resistors and capacitors have been replaced in 2014,
(for a total component cost of R82 from Communica in Cape Town!)
I will check all the values, and make sure they are as they should be.
I have connected them up to my Sansui AU101 in pre-amp mode, and they sound wonderful!
But my first question/main concern is the following:
Valves are (for each mono-block):
1 x GZ32
2 x GEC KT66
1 x Telefunken EF86
and
1 x Telefunken ECC83!?!
I know there should be 2 x EF86 (original ciscuit).
I have heard of Triode in Cascode mode mods - but I think then both EF86 valves are replaced by ECCnn valves,
after the necessary circuit modifications?
So what is going on here?
If no circuit mods, would they even work / sound good (as they do) with an ECC83 just "dropped into" an EF86 circuit?
Could this have damaged anything?
If any mods have been made - which I can't see - what will happen if I remove the ECC83 and put in an EF86?
I am happy to try this, if it won't do any damage, and either just work, or not work.
Any advice?
Thanks,
Johan
They are going to need a lot of cosmetic work, but all the resistors and capacitors have been replaced in 2014,
(for a total component cost of R82 from Communica in Cape Town!)
I will check all the values, and make sure they are as they should be.
I have connected them up to my Sansui AU101 in pre-amp mode, and they sound wonderful!
But my first question/main concern is the following:
Valves are (for each mono-block):
1 x GZ32
2 x GEC KT66
1 x Telefunken EF86
and
1 x Telefunken ECC83!?!
I know there should be 2 x EF86 (original ciscuit).
I have heard of Triode in Cascode mode mods - but I think then both EF86 valves are replaced by ECCnn valves,
after the necessary circuit modifications?
So what is going on here?
If no circuit mods, would they even work / sound good (as they do) with an ECC83 just "dropped into" an EF86 circuit?
Could this have damaged anything?
If any mods have been made - which I can't see - what will happen if I remove the ECC83 and put in an EF86?
I am happy to try this, if it won't do any damage, and either just work, or not work.
Any advice?
Thanks,
Johan
