Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Solid State Talk all about solid state amplification.

Help me figure out where this problem is happening
Help me figure out where this problem is happening
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
Thread Tools Search this Thread
Old 19th January 2008, 02:16 AM   #1
billybudapest is offline billybudapest  United States
diyAudio Member
Join Date: Dec 2007
Question Help me figure out where this problem is happening

Hi guys,
I have a beautiful marantz 2270 that has a preamp problem. Somewhere before the amp section, the left channel loses a lot of bass and low mids, I mean a ton. I am hoping you guys can help me figure out where the problem might be occurring through deduction with this information:

All inputs act the same, be it aux or tape.
Left channel preamp out is always low on bass.
All of the buttons or balances do not fix this.
The tone controls, including bass, work for the left channel! They appear to function as they should, though the bass level is just a lot lower.

Where do you guys think this might occurring? Any suggestions or thoughts or experience would be greatly appreciated. Thank you!
  Reply With Quote
Old 19th January 2008, 03:51 AM   #2
Bigred is offline Bigred  Canada
diyAudio Member
Join Date: Jul 2007
Well I can help with a service manual to start off with.
  Reply With Quote
Old 19th January 2008, 03:54 AM   #3
jaycee is offline jaycee  United Kingdom
diyAudio Member
Join Date: Apr 2004
Location: Norwich, UK
Most likely to be a bad electrolytic capacitor in the signal path somewhere. On a unit this old, it's probably worth considering replacing all of the electrolytic capacitors.
  Reply With Quote
Old 19th January 2008, 06:12 PM   #4
east electronics is offline east electronics  Greece
diyAudio Member
east electronics's Avatar
Join Date: Jan 2006
Location: Athens GREECE
Default old machines

ore used ones may have various of problems .....
you have to check :

soldering in tone control area
dirty or broken potensiometers
soldering on loudnes switch
loudness switch
electrolytics around secondary psu ( the one that creates voltage for tone control )
damaged capacitors in tone control circuit ( very rear )
general inspection may be other soldring in other areas or a previous bad repair ( wrong input capacitor or amplifier filter capacitor on amplifier board )

best way to locate if the problem is in the amplifier or the preamplifier is if possible to swap the inputs in the amplifier boards if problem mooves from ch a to ch b then preamplifier is the problem

from all that the greater chance is soldering or dirty potensiometer in the tone control area

( some of them uses a strange pot with one layer and six pins in line ..... this tend to fail easier .... )

sakis ..... www. eastelectronics.gr soon ......
  Reply With Quote
Old 20th January 2008, 03:06 AM   #5
synonymous is offline synonymous  United States
diyAudio Member
Join Date: Oct 2007
Send a message via MSN to synonymous
Make sure your speaker polarities are correct too.
  Reply With Quote


Help me figure out where this problem is happeningHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Whats happening everyone? TypicalBasher Introductions 2 24th November 2008 09:46 PM
What is happening to the forum? Christer Everything Else 0 25th June 2006 01:44 AM
very odd thing happening in my amp... help AudioGeek Tubes / Valves 15 25th September 2005 02:34 AM
What's happening in BPD? Richard Moon Subwoofers 1 24th March 2002 02:48 AM

New To Site? Need Help?

All times are GMT. The time now is 12:35 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio