Quad II question: High B+ a problem?
"Patrick Turner"
I recently rebuilt a couple of Quad II's from what was pretty bad shape
with parts missing etc. Everything now works and sounds great and even
looks mostly original... except for the highish B+ Im getting. This is the
new configuration:
Rectifier tube (5AR4) - 33uF/450v - the original choke - 47uF/450v
I am not sure you know what you are doing.
** The OP knows - his description is of the entire DC supply circuitry.
The changes are the rectifier and filter cap values.
If nothing else is changed in an original Quad-II amp, the The use of GZ32
or GZ34/5AR4 makes only a slight rise of B+ which is entirely OK and nothing
to worry about.
** The voltage rises by about 30-40V so is significant.
You don't need to do every single thing I usually do to old Quads to get
better music from them. The use of a single 180r common cathode Rk is
terrible.
** Hardly a fair comment seeing as it works so well with the specified
output valves ( and most 6L6GCs ) long as they are still in good condition.
..... Phil
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