Single ended tube amp Lead Dressing - diyAudio
Go Back   Home > Forums > Live Sound > Instruments and Amps

Instruments and Amps Everything that makes music, Especially including instrument amps.

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 7th June 2012, 04:02 PM   #1
diyAudio Member
 
Join Date: Dec 2011
Default Single ended tube amp Lead Dressing

I finished my AA764 Fender Blackface Vibro Champ Amp and it sounds great! Except........
I am having a ground issue with the guitar on this amp. I know my guitars are grounded as well as they can be, as they don't hum like this through any of my other amps.
I used shielded wire from input jack to V1a. However I didn't terminate or solder the the shielding to ground on both sides of the run. Should I do that? The shielded cable has the hot and shield isolated from eachother of course.
Lead dress looks good in the amp, however it could be that too.
Thought about moving the input jack resistors closer to V1a.
Any pointers where to solve this slight hummmmmmm.????????
It cancels when I touch strings of guitar and input jack of amp.
Do I need to isolate the input and output jacks????
Any thoughts?
Thanks for the help!!!!!!!
  Reply With Quote
Old 14th June 2012, 04:50 AM   #2
diyAudio Member
 
Join Date: Oct 2004
Location: Adelaide South Oz
The input jack should be an insulated type which does not connect the ground side to the chassis.

Then use shieled wire from the jack to the amp input - the shield at the amp circuit end end should connect to the 0V (ground) side of the grid leak resistor.

If the Input Jack is the non-insulated type then you only need to connect the shield at one end and it probably won't matter which end - so long as the circuit uses a 0V connection direct to chassis. If you use a back to back diode or 10 Ohm resistor or any of those other 0v to Chassis schemes then you must use insulated input jack with shiled connected both ends as per the top of this post.
Hope this helps,
Ian

Last edited by gingertube; 14th June 2012 at 04:54 AM.
  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
6HF5 sweep tube single ended amp AJT Tubes / Valves 25 6th July 2014 03:05 AM
Single ended KT88 tube amp BillFussIII Swap Meet 5 10th January 2012 09:11 PM
Single Ended Tube Amp For Sale scott17 Swap Meet 4 23rd August 2011 02:28 AM
WTB: Single Ended tube amp bepatient Swap Meet 4 29th January 2006 09:11 AM
FS: 6BM8 Single Ended Tube Amp mourip Swap Meet 0 19th April 2005 11:06 PM


New To Site? Need Help?

All times are GMT. The time now is 07:59 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