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Preamp making loud pitched morse code sound

I just hooked up the final parts of my system this weekend and am getting this pretty awful noise that I can't figure out the source of. I would be GREATLY appreciative if someone were able to help me out. I'm very new to the hifi world so needless to say, it's pretty frustrating to finally have everything hooked up and get an awful noise when I was expecting smooth sailing (silly me?). 

I have a cambridge cxa81 integrated amp and kef ls50 meta speakers that I've had for a few weeks now listening to digital music through Tidal until my turntable/preamp arrived and it's been a great experience. I finally picked up my turntable/cartridge/preamp on Tuesday - rega p6 turntable, hana ml cartridge and sutherland kc vibe phono at stereo exchange in nyc. the sales rep was very nice and put everything together for me in the store to make sure things worked properly before I left. When he hooked up my turntable/preamp to a receiver/speakers in store, it sounded great but it was picking up some radio frequency which we found very strange. We thought maybe it was an issue with where we were and that the issue would go away when I hooked it up at home.

https://www.icloud.com/photos/#0sPNXSiNWROvNUUnRmh1YSglg here is a video of the issue i'm experiencing. I've been searching online since this afternoon and can't really find an answer. Everyone I hear talking about the kc vibe raves about how quiet it is which is obviously the opposite of what I'm experiencing. As soon as I turn up the volume to around 10-11 o'clock, you start to hear it at a decent level, then it gets louder as I turn the volume up. It's subdued when I actually play music, but you can still kind of hear it in the background if you try, or put your ear closer to the speaker. 

What I've tried from the time I've spent online looking for an answer: turned phone on airplane mode and turned off router (not sure how much that'll since I live in Brooklyn where RF/EMF is flying around everywhere), plugged the preamp into a different power source then everything else is plugged into, moved the preamp further away from the system setup, unplugged my tv...I think that's it so far. 

I also plugged my previous turntable, audio-technica lp120 to the kc vibe and still hear that sound. When I plug the lp120 straight to the receiver and use the onboard preamp, I don't hear anything. 

There's absolutely no noise when I switch the input to listen to music digitally, just when i turn the preamp on. 

Any suggestions? 
wally828
ghosthouse's avatar
ghosthouse
4,321 posts
 
Is there noise when you plug the Rega TT directly into your (Cambridge CX81?) receiver?

I’m guessing the Sutherland preamp is picking up some kind of digital interference.

Tried calling Sutherland for tech support?

If the store is not too far, consider taking your receiver, turntable and the phono-preamp back to the store. See if there’s noise there. If yes, try another Sutherland pre-amp in the store.  Maybe your phono pre is defective?

OP = original poster (i.e., YOU).
millercarbon's avatar
millercarbon
12,531 posts
 
I listened to the noise, thanks for sending the file. You are right, Morse Code: same thing over and over again: LET ME OUT... LET ME OUT....
millercarbon's avatar
millercarbon
12,531 posts
 
Sorry, couldn't resist. Besides, you know the answer. You heard it in the store: RFI. The phono stage is picking up radio frequency noise. It was different in the store because different RFI environment, also different cable routing. Play with the phono lead and RCA connectors, and if you hear the noise change this is confirmation. 

Your choices are fuss around until you track down the solution, or take the rig back and say what it did here in the store it is doing at home, let's try something else. 

If you want to try and track it down, first clean all contacts with alcohol and a clean cloth. Then try moving the phono lead. Every wire is an antenna, they are all chock full of radio frequency noise, it is just random chance that some of it gets "tuned" out to what you are hearing. All the rest of the time that same noise is there, just not in a form or at a frequency you hear well enough to recognize as noise. But it is there. Trust me. One of the many reasons some interconnects and speaker cables and power cords sound better than others is their ability to reject RFI. 

Wait I just noticed you are in Brooklyn. I would remove the cover and check. Just in case there is someone living in there. 
wally828 OP
9 posts
 
@ghosthouse thanks for the OP clarification, lol. When I plug the TT directly into the receiver, no noise at all but the sounds isn't amplified at all (obviously) so maybe it's there and I just can't hear it, but nothing audible. 
Stereo Exchange talked to Ron Sutherland directly this morning. He's a small company and said he's all about customer satisfaction so he's going to take the preamp back if we're unable to come up with a solution. He did tell them that the preamp "has a wide band design and sensitive to RFI," which should definitely be a huge disclaimer to customers prior to purchasing. Living in NYC, there's no way to avoid RFI and I don't ever want to have to turn off my phone, wifi, lights, wear a tin foil hat to have to listen to records lol.
We heard the noise when we plugged my preamp and TT up at the store before I left and the noise was worse, it was actually picking up radio signals. 
I'm most likely going to take it back but now I have to figure out which preamp to get that isn't going to give me the same problems :/
oldhvymec
5,101 posts
 
OP, Original Poster, On Point, Other Person, Oscar Pennywinkle. :-)
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