Jump to content



Sign up for a free account to remove the pop-up ads

Signing up for an account is fast and free. As a member you can join in the conversation, enter contests and remove the pop-up ads that guests get. Click here to create your free account.

Photo
- - - - -

Capacitor change in preamp


This topic has been archived. This means that you cannot reply to this topic.
5 replies to this topic

#1 of 6 OFFLINE   Yogi

Yogi

    Screenwriter



  • 1,741 posts
  • Join Date: Jul 25 2002

Posted May 02 2003 - 04:19 AM

I am going to replace the output capacitors in my ASL 2004DT preamp with auricaps. I have never done something like this. So are there any special skills I need to acquire before I embark on this endevour? Any special tools apart from a saudering iron some silver solder? I am thinking its a plain pull out the old cap and put the new one in and solder away. I did some soldering about 15 yrs back but it was simple soldering of wires. So please advice me if there is anything else that I should know about. Also what kind of improvement should I hope to see with this change? Any advice to this novice would be greatly appreciated.
The truth is not out there but within you.

#2 of 6 OFFLINE   Yogi

Yogi

    Screenwriter



  • 1,741 posts
  • Join Date: Jul 25 2002

Posted May 03 2003 - 04:31 AM

Last night I changed the two output caps from Multicaps to Auricaps. I also changed two DC blocking Benning caps with Auricaps of same rating and two other Benning caps in the signal path with Auricaps. Took me two hours to do it mainly because of the inaccesability of the PCB (had to dissassmble almost everything). In any case changed everything and soldered them with silver solder. Hooked it to my system and fired the preamp. Initial findings are that the mid-range now seems a little more juicier with a little more body. The top end also seems slightly smoother. The bass is the same with either caps. Cant really comment on the soundstage or the image specificity. I am already loving the new sound.
The truth is not out there but within you.

#3 of 6 OFFLINE   Chu Gai

Chu Gai

    Lead Actor



  • 7,270 posts
  • Join Date: Jun 29 2001

Posted May 03 2003 - 10:17 AM

hey buddy, you still humming?

#4 of 6 OFFLINE   Yogi

Yogi

    Screenwriter



  • 1,741 posts
  • Join Date: Jul 25 2002

Posted May 03 2003 - 12:42 PM

Yes Chu sadly I am still humming. Although the nature of hum seems slightly different the buzz component is slightly lower but the hiss component remains. I have no idea why. Could it be related to the leakage current of the new caps?
The truth is not out there but within you.

#5 of 6 OFFLINE   Chu Gai

Chu Gai

    Lead Actor



  • 7,270 posts
  • Join Date: Jun 29 2001

Posted May 03 2003 - 01:31 PM

God Yogi, so many possibilities, some of which were touched upon in an earlier thread, and honestly, without proper test equipment, we're all reduced to speculation and trial and error. And you know me Yogi, I hate to spend other people's money on whims. I think one thing I'd be doing is taking a look at the grounds and trying to determine if they might be at different potentials from each other. Have you considered posting over at AA or on Usenet?

#6 of 6 OFFLINE   Yogi

Yogi

    Screenwriter



  • 1,741 posts
  • Join Date: Jul 25 2002

Posted May 04 2003 - 01:39 AM

I did post at AA but that wasn't much help. All the grounds on the circuit boards etc in the preamp are screwed to the chassis. So I dont know what else could be causing the hum. I tried re-routing the various wires, sheilding them with copper tape (and grounding the tape) but still the hum remains.
The truth is not out there but within you.