Need help with hum and faint left channel on my S5 Electronics kit - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

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 14th January 2007, 12:02 AM   #1
Neville is offline Neville  United States
diyAudio Member
Join Date: Jul 2004
Location: Georgia
Angry Need help with hum and faint left channel on my S5 Electronics kit

I have everything setup in my Hammond chassis with Hammond 1609 trannies, but I get a hum with very faint music in the left channel. With the help of another DIY gentleman I have successfully "cleaned" out my wiring, keeping wires as short as possible and a few other things, but still get the hum.

Now I did notice that with the stock pot, if i disconnect the ground lead to the left channel, music comes thru but with a lot of hum/buzz and if I connect the ground lead to anywhere on the pot housing, I get clear sound but cannot use the pot to control volume. I have used a new pot and still have the same issue.

Going crazy here ..... can somebody please offer a newbie advice or anything that might help me ?

btw I have soldered the resistors and caps on the otherside of the pcb so I could have the tubes protrude thru the holes in my chassis. I also have checked all resistor values and they are good. I have checked and double checked and triple checked all solder joints. With my very limited knowledge in tubes/diy , I suspect I have a short either in my RCA left input or going out to my speakers but don't know how to resolve it. I also do not feel comfortable taking voltages with the amp on so have only done it disconnected.

  Reply With Quote
Old 14th January 2007, 01:10 PM   #2
Neville is offline Neville  United States
diyAudio Member
Join Date: Jul 2004
Location: Georgia
I have read posts that mention checking that the rca inputs and speaker connections do not touch the chassis. I'm pretty sure that is not the case but decided to put electrical tape around the parts that could touch it. Still have the issue.

Regarding grounding, I have the 3rd green IEC wire attached to the chassis. Hammond 1609 are wired to the chassis ground.
RCA inputs have a single ground going to the back of the PCB where the trannies can be grounded. POT does not have any ground, did not make any difference with or without the ground lug.

I dont think this issue is specific to the S5 kit but more of a "always do this or that when grounding" or something procedural.

Any advice ?
  Reply With Quote
Old 14th January 2007, 01:18 PM   #3
SY is offline SY  United States
diyAudio Moderator
SY's Avatar
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 2
Photos are often helpful in situations like this.

Basic rules: Make sure that the IEC green wire is securely attached to the chassis, and that all other circuit grounds come together at a common point near the input. The circuit grounds can be attached to the chassis at that point either directly or through a small (10-30R) resistor. Some people use back-to-back paralleled diodes to tie the circuit ground to the chassis.
"You tell me whar a man gits his corn pone, en I'll tell you what his 'pinions is."
  Reply With Quote
Old 14th January 2007, 07:58 PM   #4
Neville is offline Neville  United States
diyAudio Member
Join Date: Jul 2004
Location: Georgia

I have upload a few other pics to this site.

Both switch and volume do not have any plastic or rubber grommets between it and the chassis.
  Reply With Quote
Old 15th January 2007, 10:58 PM   #5
Neville is offline Neville  United States
diyAudio Member
Join Date: Jul 2004
Location: Georgia
Success at last ! I grounded the pot with the lug and also added electrical tape to the sides and that worked. Now I have both channels working apart from the humand I can live with the hum. I sometimes have to knock the case when it goes to the right channel ???????

but I am happy just doing that-pretty sad but a milestone for me
  Reply With Quote


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
low audio on left channel jvc vn-300 stevodude Solid State 8 10th February 2014 02:15 PM
K-502 Left Channel is out udailey Tubes / Valves 3 21st March 2008 05:12 PM
DH-220 left channel dead rfarn Solid State 8 11th May 2006 11:35 PM
Pioneer A400 faint distortion on right channel Growers Solid State 7 30th April 2004 11:14 AM
One channel has VERY faint output jjdche Car Audio 4 18th March 2004 04:22 PM

New To Site? Need Help?

All times are GMT. The time now is 10:08 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2