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Wallace
17-03-2008, 14:42
Not gonna post here much since I dont have the experience in fancy systems, but wanna get this off Wallace's chest.

The height of the extent of Wallace's audiophility is a Fisher X101 tube amp (got for free).
Wallace really wants to get into tubes cos they fit with the vinyl aesthetic as a baby's bum fits to a wax potty.

Over non-tubes, Wallace does notice DISTINCT improvements in especially natural bass decay and clarity of vocals.

Anyways, problem is the hum.
Understanding is that this is basically due to waxpaper-deterioration cross over in the transformers and nothing can be done other than going expensive route of new trans.

(Wallace has read that extensive article on proper grounding -so this is not a grounding probby.)

Any hope?
(Ive cleaned the tube sockets with "Blue Shower" tech spray.
(Is something like De-oxit spray much to be recommended over usual spray?)

WikiBoy
17-03-2008, 14:50
Not gonna post here much since I dont have the experience in fancy systems, but wanna get this off Wallace's chest.

The height of the extent of Wallace's audiophility is a Fisher X101 tube amp (got for free).
Wallace really wants to get into tubes cos they fit with the vinyl aesthetic as a baby's bum fits to a wax potty.

Over non-tubes, Wallace does notice DISTINCT improvements in especially natural bass decay and clarity of vocals.

Anyways, problem is the hum.
Understanding is that this is basically due to waxpaper-deterioration cross over in the transformers and nothing can be done other than going expensive route of new trans.

(Wallace has read that extensive article on proper grounding -so this is not a grounding probby.)

Any hope?
(Ive cleaned the tube sockets with "Blue Shower" tech spray.
(Is something like De-oxit spray much to be recommended over usual spray?)


Give the transformers a good spray with WD40.

Marco
17-03-2008, 14:57
Not gonna post here much since I dont have the experience in fancy systems, but wanna get this off Wallace's chest.


Wallace, it doesn't matter one iota that you don't have much experience with "fancy systems". You're very welcome to offer your opinion - in fact I invite you to do just that!

The Art of Sound is not an elitist audio forum - we have members of varying levels of experience and with all types of systems, so don't worry about not knowing much about "fancy systems".

I'll let one of our valve gurus answer your question, as they'll do it better than I will.

Marco.

jcbrum
17-03-2008, 15:12
Hi Wallace, welcome, I gave up valves in 1989, but don't be put off by anyone, ask away and I'm sure someone will help. JC.

Wallace
17-03-2008, 15:32
Give the transformers a good spray with WD40.

Serious?
You mean, open the transformers and spray the paper???

WikiBoy
17-03-2008, 15:39
Serious?
You mean, open the transformers and spray the paper???

No need WD40 is anhydrous, it is attracted to and will go anywhere there is damp, so it will seek out the problem. It will re-insulate the transformer but will have to be redone about once every couple of months. It is not long term cure as the paper will continue to deteriorate.

anthonyTD
17-03-2008, 19:20
Not gonna post here much since I dont have the experience in fancy systems, but wanna get this off Wallace's chest.

The height of the extent of Wallace's audiophility is a Fisher X101 tube amp (got for free).
Wallace really wants to get into tubes cos they fit with the vinyl aesthetic as a baby's bum fits to a wax potty.

Over non-tubes, Wallace does notice DISTINCT improvements in especially natural bass decay and clarity of vocals.

Anyways, problem is the hum.
Understanding is that this is basically due to waxpaper-deterioration cross over in the transformers and nothing can be done other than going expensive route of new trans.

(Wallace has read that extensive article on proper grounding -so this is not a grounding probby.)

Any hope?
(Ive cleaned the tube sockets with "Blue Shower" tech spray.
(Is something like De-oxit spray much to be recommended over usual spray?)

hi wallace,
hum in valve amplifiers can be due to sevral problems other than the transformer interleaving insulation, which is what i think your describing.
here are a few other things to consider,

output valve DC balance on push-pull amplifiers. ie, depending on how the output valves are biased...

leaking interstage coupling capacitors.tell-tale signs of this are red glowing anode/plate structures in the valves themselves.
bias circuits not working properly, or in the case of grid biased amps, insuficient smoothing on the bias supply..
these are just a few of the more common faults to check for.
WARNING !!!PLEASE BE ADVISED, ALL VALVE EQUIPMENT CONTAINS POTENTIALLY LETHAL VOLTAGES, SO BEFORE REMOVING ANY COVERS, OR CARRYING OUT ANY CHECKS, MAKE THE SURE THE UNIT IS SWITCHED OFF, AND UN-PLUGGED FROM THE MAINS, EVEN THEN, SUCH CHECKS AND REPAIRS SHOULD ONLY BE CARRIED OUT BY A COMPETENT, TRAINED PERSON OR TECHNICIAN.