static shocker maybe?
 

:rolleyes: Since I fitted an Alps blue...Not the best pot in the world....scratchy from the start, there sending me another..I trust?

Been experiencing distortion troubles, all down to the pot, Fitted the usual earth ring betwixt pot front and chassis ground, improved matters..Dont need any assistance just to share this odd phenomenon?

when playing music, after say five minutes..it starts the wobbly distorted sound, If I get up.. to approach the amp...it suddenly as if by magic stops!:bigeyes:


Good job I didnt do the shunt mod!:rolleyes:

Anyone ever taken an alps blue velvet apart? what a load of cra.......*!

maybe a bad pot...maybe a bad cap
 

Often, if there's DC on the pot, it will behave as you describe.
A leaky coupling cap could do this. Of course, it could be a bad
pot...Perhaps you could check for DC voltage on the top of the pot...
this also might be tough given the flakey nature of what you describe.
Good luck hunting.

Re: static shocker maybe?
 

Definitely check for DC on the pot.

It sounds like you may also have some RFI issues too. A flaky ground connection can act like an antenna.

what kind of pot did you say?

:D

An, A'a.........aL..........

havent got round to the coupling caps!:( yet...

150 ua's was looking for some Polypropylene replacements, all I can find is orrible axial mfd's or 1 million V motor runs so far!:rolleyes:

under normal conditions an electrolytic should not have enough leakage to do what you describe. a bad electrolytic will. you may get into trouble replacing a 150uf electrolytic with a poly. the extra lead length will act as an antenna. 1.5" (3.3cm) is about right to act as a 1/4 wave antenna at 2.4Ghz which is where a lot of wireless network stuff runs. if you include the cap body (the cap itself acts as a nice antenna, very efficient since the conductor diameter is now over 1/10 wave) you start getting into the 1/4 wave length of cell phones, etc...

AH!

Funny you should say the uncJed ....I swapped two short axial output caps with chuffing great 4cm radials just before the ....er... That pot:xeye:

I had no idea!:D

How to rectify the situation? I like the sound with the new caps, broader soundstage......Dont really want a filter coz ive spent lots of time removing all the extraneous junk from within..Havent even got a humble LED! One input..one out.............


:xeye:

I'll have to take them out wont aye!

or find a way to mount them without the antennae legs, One's gotta be 4" long....

Ah Poo!:xeye:

Hi,
which is worse?
the sound you need or the interference you don't need.
Just choose.
It's called compromise.

You can also design out much of the interference, but, that requires you to make more compromises, like putting back some of your offending components put in there to reject the interference. are you ready to apologise to Alps and to our Members for posting misleading information?

Have you thought about shielding at all? I would think a well shielded circuit could eleviate the interference problem, while still keeping the sound you like. Of course, I'm no engineer.... yet :-D