Hiss with AC-DC buck supply


  #1  
Old 11-25-17, 05:30 PM
M
Member
Thread Starter
Join Date: Nov 2017
Location: italy
Posts: 2
Upvotes: 0
Received 0 Upvotes on 0 Posts
Hiss with AC-DC buck supply

Hi everybody,

i bought two bucks 220V to 9V like this

https://www.ebay.com/itm/NEW-High-G...hash=item3aedf56b33:m:mU9l2J_hWAfiMR8zs66GTXw

to power two pedal effects for my guitar. It works all but I hear from the speaker a hiss that changes the frequency depending on the changes I make to pedal effects. I would like to be able to fully delete this hiss but I do not know how to do it.
Can someone help me to fix it ?

Many thanks !
 
  #2  
Old 11-25-17, 06:38 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Jersey
Posts: 63,864
Received 3,749 Upvotes on 3,362 Posts
Welcome to the forums.

I changed the title as you are converting AC to DC.

Normally switching supplies used for audio are well shielded and filtered. With the price of those.... they are neither.

You'd be better off using linear type plug in wall cubes. Switching supplies require shielding and even then cause noise in low level audio devices.
 
  #3  
Old 11-26-17, 01:48 AM
M
Member
Thread Starter
Join Date: Nov 2017
Location: italy
Posts: 2
Upvotes: 0
Received 0 Upvotes on 0 Posts
Sorry for the title, I was distracted. A linear power supply with a transformer I have already realized but, in addition to being a bit bulky, that would not be the real problem, it interferes with the inductance of the wah wah I have in the pedalboard. In this video
https://www.youtube.com/watch?v=Tqqqe7xReII
a mu-metal sheet solves the problem of noise, but it costs too much.
Cheers
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: