2. amps-preamps
  3. 147116-79353

Phono preamp make crackling noise

Looking for advise from any of the audio Gurus.

My set up consist of Unison research Unico pre connected to Auris audio Forte 150 mono blocks, my speaker are Focal Sopra N3. I also have BLUESOUND NODE 2 (Dac/ streamer).
I do not have any issue with noise when I play music through my BLUSESOUND NODE either Tidal or Spotify..
I recently purchased Unison Research Simply phono Tube Phono amp with separate power unit. As soon as I connect the ’Simply phono’ to pre amp and set to appropriate input I get crazy cracking noise on my speakers. It is not a ’Hum’ like you hear with ground issue. I don’t even need to switch on the Turntable. It overpowers the sound of my music.
I am trying to eliminate each piece of my equipment. I even took my Phono preamp and the preamp to a Hifi audio store . we connected my equipment at the store and amazingly it played without any noise. I have changed interconnects / power cables still it is noisy . Looks like the issue is in the wall electrical. I just moved to a new house.
Any help will be appreciated. I even tried to move my NAS drive away. Just driving me nuts!!!!
vishu
vishu's avatar
vishu OP
28 posts
 
The factory tube is  four ECC83 Valve – also known as the 12AX7.
I tested it on MM cartridge. 
The store is figuring it to be issue with my wall power and wifi adapters noise being picked up by my phono stage and amplifying  it many times.
I have an electrician coming today to check it out. 


cytocycle
1,043 posts
 
is the turntable grounded to the phonostage? and have you also tried adding a ground from phonostage to the preamp via a screw on the chassis if it doesn't have a grounding post.  Most likely a grounding issue.
jayctoy's avatar
jayctoy
4,393 posts
 
Cytocycle agree that’s what happen to me, I have to buy the Audioquest ground wire...from tt to preamp...
vishu's avatar
vishu OP
28 posts
 
I resolved my issue. I tried seeking help in various forum and personally spoke with  guys at local audio store. I took my Unison research 'simply phono' and my Rega P3 turntable with my interconnects to the store and hooked it up to their system. There was no noise of any kind . 
Finally I found the culprit. I had a 'wifi adapter'  plugged into the electrical socket close to my audio equipment from which I was hard wiring my NAS drive and Bluesound node streamer. 
Just removed the 'wifi adapter' and the noise disappeared. These wifi adopter create a big noise in the net work.  I hard wired the USB directly from main Router and have no issues.


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