Jim:
It could be the Pearl / Ono's noise floor, but seems a little loud to me. I've been studying Rod Elliott's article on Earthing; the article you suggested is also helpful -- thank you.
I've ordered a bunch of 35A bridge rectifiers from ebay. The seller's in HK so there will be a 3 week or so delay before I can implement a DC blocker (presumably in the power distribution box, though perhaps another as well in the power supply for my phono preamp).
Thanks to all for the guidance. I'll report back in due course.
Regards,
Scott
It could be the Pearl / Ono's noise floor, but seems a little loud to me. I've been studying Rod Elliott's article on Earthing; the article you suggested is also helpful -- thank you.
I've ordered a bunch of 35A bridge rectifiers from ebay. The seller's in HK so there will be a 3 week or so delay before I can implement a DC blocker (presumably in the power distribution box, though perhaps another as well in the power supply for my phono preamp).
Thanks to all for the guidance. I'll report back in due course.
Regards,
Scott
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Just a thought here- it sounds like you have a rather complicated setup with lots of moving and non-moving pieces. To the extent that you can isolate one piece of equipment at a time and see what is going on will help.
Start with just your amp and speakers - no other inputs connected. What do you hear?
Now short the amp inputs for each channel? Any changes?
Next add the pearl (with power, but not inputs). What do you hear?
Short the input for each channel on the pearl. What do you hear?
Fire up one air compressor for the TT. Has anything changed?
etc...
The basic idea is to examine only a single variable at a time. This should help narrow things down, especially in a complex system.
Start with just your amp and speakers - no other inputs connected. What do you hear?
Now short the amp inputs for each channel? Any changes?
Next add the pearl (with power, but not inputs). What do you hear?
Short the input for each channel on the pearl. What do you hear?
Fire up one air compressor for the TT. Has anything changed?
etc...
The basic idea is to examine only a single variable at a time. This should help narrow things down, especially in a complex system.
Pass DIY Addict
Joined 2000
Paid Member
Sorry, it's the computer scientist in me 
Large and complex problems are hard to solve. But, it you iteratively deconstruct the large problem into successively smaller and smaller sub-problems, systematically and logically addressing each smaller piece is nearly trivial...
I'm sure you'll track this down! Navigating a rats nest of wires is what makes it hard...
Large and complex problems are hard to solve. But, it you iteratively deconstruct the large problem into successively smaller and smaller sub-problems, systematically and logically addressing each smaller piece is nearly trivial...
I'm sure you'll track this down! Navigating a rats nest of wires is what makes it hard...
Folks:
Here's the follow-up. After extensive noodling, I've determined that the bulk of the background noise is being caused by the turntable's air pumps. Next, the powerline adaptor used to connect my basement server to the house router adds a curious low-level weirdness. And my SG-4 sinewave generator adds to the noise very slightly. With those devices turned off or disconnected, the white noise I'm hearing through the phono preamp is virtually indistinguishable from the white noise I'm hearing through the other preamp inputs. The phono input noise might be 1 dB louder -- I can't tell for sure.
The bottom line is that I can live with things as they are now. If I hadn't gone all OCD on this issue I'd let it drop, but I will try one or two of the DC-blocking and/or noise-reduction suggestions found at Rod Elliott's website (the parts are en route). If something magical occurs, I'll post a quick note.
Regards,
Scott
Here's the follow-up. After extensive noodling, I've determined that the bulk of the background noise is being caused by the turntable's air pumps. Next, the powerline adaptor used to connect my basement server to the house router adds a curious low-level weirdness. And my SG-4 sinewave generator adds to the noise very slightly. With those devices turned off or disconnected, the white noise I'm hearing through the phono preamp is virtually indistinguishable from the white noise I'm hearing through the other preamp inputs. The phono input noise might be 1 dB louder -- I can't tell for sure.
The bottom line is that I can live with things as they are now. If I hadn't gone all OCD on this issue I'd let it drop, but I will try one or two of the DC-blocking and/or noise-reduction suggestions found at Rod Elliott's website (the parts are en route). If something magical occurs, I'll post a quick note.
Regards,
Scott
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