Aragon 24K Volume control noise and dc - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 15th August 2014, 09:50 PM   #1
rickcl is offline rickcl  United States
diyAudio Member
 
Join Date: Mar 2003
Location: California
Default Aragon 24K Volume control noise and dc

Hello. I have an Aragon 24K preamp that has a little scratchiness in the volume control in the first 1/4 turn on the left channel. I had a cheap linear pot. so I stuck that in circuit and it did the same thing. I took the original Noble pot. apart and cleaned it. It's fine.

I did measure -49mv across each the sliders to ground. I did stop all the noise by soldering in a couple of 4.7uF NP caps in series with the slider.
There are a couple trimmers close to the line amp. I was wondering maybe these are offset adjusts.
For ref: power supply output: -24.70 and +25.32

Thanks all! I am stumped....
  Reply With Quote
Old 15th August 2014, 11:29 PM   #2
diyAudio Member
 
Join Date: Nov 2004
Location: Germany
Sounds like input bias current of the following amplifier stage is at fault, which would indicate either a leaky existing coupling cap or none being present at all (which would be a design issue). It's hard to tell more without a decent idea of what the circuit looks like. Seems to be a discrete affair.
  Reply With Quote
Old 17th August 2014, 05:06 PM   #3
rickcl is offline rickcl  United States
diyAudio Member
 
Join Date: Mar 2003
Location: California
Default Schematic available

I have the schematic now so if anyone want to take a stab at troubleshooting this one I would be really grateful.

Just shoot me a PM with your email address.

Thanks, Rick
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Aragon 24K sp PreAmp by Mondial Designs, possiblity for component/wiring upgrades? babylondrifter Solid State 1 8th January 2014 03:05 AM
ESD noise from finger and volume control elvischan917 Chip Amps 4 12th May 2012 05:01 PM
Problem with Aragon 24k - pop and low output Richter17 Solid State 0 25th December 2009 02:26 AM
volume control hum/noise cbutterworth Tubes / Valves 6 8th April 2007 07:47 PM
Help me regarding very low Supply Ripple output noise DC volume control unit electronist Parts 0 31st December 2003 09:29 AM


New To Site? Need Help?

All times are GMT. The time now is 02:22 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2