Author Topic: cleaning of APLS master volume att.  (Read 5625 times)

Audioplatinum Service

  • Jr. Member
  • **
  • Posts: 59
  • Karma: +9/-0
    • Zagreb, CROATIA
    • Embrio Production Studio
cleaning of APLS master volume att.
« on: December 29, 2013, 10:34:21 AM »
For some time we have a problem with noise and crackled sound from ALPS master att. on 651..Yesterday I took it out from master section, unsolder all wires, and disassemble all decks with ceramic plates...There are a lot of dirt inside on contacts and wiper...all contacts are cleaned with isopropyl alcohol,shaft is lubricated with silicone oil and all this is assembled and put inside 651, nice weekend job...after all, crackled sound is gone, noise is gone and now I have clean master att. which is like new!!!   ;D ;D

Care must be taken with ceramic plates, resistive film is laser cutted on ceramic, and that resistive part do not clean with isopropyl alcohol, only gently wipe with dry hygienic stick...

Cheers!

Raf
Audioplatinum Service
"A clean desk is the sign of a sick mind..."

marcmozart

  • Sr. Member
  • ****
  • Posts: 483
  • Karma: +29/-0
    • Frankfurt/Germany
    • Mozart & Friends
Re: cleaning of APLS master volume att.
« Reply #1 on: December 29, 2013, 09:16:10 PM »
Great post - I was thinking to do the same, after I had great result bathing my routing cards in Isoprop.Alcohol. Got a bit of crackling on my Master Pot as well.
1992 SSL 4048 G-Series
Mix Engineer Blog
http://www.mixedbymarcmozart.com

Audioplatinum Service

  • Jr. Member
  • **
  • Posts: 59
  • Karma: +9/-0
    • Zagreb, CROATIA
    • Embrio Production Studio
Re: cleaning of APLS master volume att.
« Reply #2 on: December 29, 2013, 09:22:30 PM »
Last picture is half dirt and half cleaned...nice difference between...I had big problem with master pot, and now all problems gone...  ;)


Cheers!
Raf
Audioplatinum Service
"A clean desk is the sign of a sick mind..."

kilmister

  • Global Moderator
  • Sr. Member
  • *****
  • Posts: 252
  • Karma: +11/-0
    • Hellsinki, Finland
    • 5 by 5 Audio
Re: cleaning of APLS master volume att.
« Reply #3 on: December 30, 2013, 08:09:12 PM »
Well done Raf!
-- Too much amp power is just right --

-- 5 by 5 Audio
-- 5 by 5 @ Facebook

michaeldtech

  • Jr. Member
  • **
  • Posts: 77
  • Karma: +6/-0
    • 2Q
Re: cleaning of APLS master volume att.
« Reply #4 on: January 05, 2014, 02:17:06 PM »
Love that pot!
You should definitely re-condition the switch contacts with a ProGold or similar product.  The fix will last longer and there is less wear on the metal to metal contacts.
Mike

mike_signo

  • Newbie
  • *
  • Posts: 13
  • Karma: +1/-0
    • London
    • Signorini Audio Devices
Re: cleaning of APLS master volume att.
« Reply #5 on: August 17, 2024, 12:37:07 AM »
Hey,
I've tried opening the pictures but they are giving me 404 - attachment not found error.
I would be super grateful if someone could share some pictures of the inside of one of these switches.
I'll have to attempt the same repair on an old E series and I'm trying to find as much info as possible before I start pulling cards :)

All the best
Michele

G-Spot

  • Newbie
  • *
  • Posts: 9
  • Karma: +0/-0
    • Germany
Re: cleaning of APLS master volume att.
« Reply #6 on: September 16, 2024, 11:17:59 PM »
Yes... I'm also interested. After removing the main vol attenuator from the central section, I'm here looking at it and wondering how to remove the shaft so I can access the decks with the ceramic plates... I removed the two long screws that hold the 4 decks together and the bottom cover, so I can see the bottom ceramic plate, but the wiper and the decks in between are still connected together by the shaft...  :o

Any tips?