I recently spent alot of time & love on my G9000
(Full thread here: https://audiokarma.org/forums/index...other-protector-wont-come-off-thread.1095294/)
It's got two new F2806 boards , new power caps (with these boards: Moderator note: link to eBay removed as that would violate AK rules.
and alot of new parts on F2809. Not all caps have been replaced but more than half I would say; similar for transistors and diodes.
It works like a charm and I love it;
However - a few days into my honeymoon I realized that there's a very very noticeable humm when there's nothing playing. Loud enough that I hear it when listening to music softly and there' s a silence/gap, or even in between notes.
- That's when using the pre-amp. Even with nothing hooked to aux - I'll get the hum; and likewise when hooked to my source there's a hum.
- When disconnecting the pre-amp; it's almost un-noticeable - but as soon as I hook up something to the power amp, the very same humm appears.
I'm pretty certain it wasn't there before I swapped the big caps (which was my last job on the unit) but cannot be certain. The speakers I used to test when working on the unit are very large columns that seem to react alot less to the noise (I assume, less efficient so it's not being heard that much?) - so it *may* have been there during my pre-cap-swap testing but I'm almost 95% certain no.
When I hook them on bookshelves (Rogers Ls4a) - the humm is just so damn "loud" it's driving me crazy. (It's not 'loud' per say, but its pretty noticeable and .. annoying). I'm feeling like Alex in a clockwork orange - although instead of beethoven its that dreaded humm.
---
I'm at a loss... I don' tknow where to start debugging that. I've had tremendous of help from board members getting it to work - I cannot be thankful ever enough for it - and it seems with you guys I'm helpless. Any ideas ?
The humm looks like this:
Granted, it doesn't look like much but on small speakers its loud.
Almost the same buzz that Marty McFly experiences at the beginning of BTTF 1 when he's waiting for Doc at his house and plugs in his guitar on an overdrived amp (that ends up exploding.)
I simply can't enjoy any classical, jazz, etc. as the humm blends with the music at low levels
---
I know its foolish to try and record the sound but in case... that's me switching the spks on/off while trying to record close to the driver.
https://drive.google.com/file/d/1KB37ZXTuoq1erJLCUtiQ2srcumy4ynDN/view?usp=sharing
(Can't verify if we hear it, cause on my setup I always hear it!)
===
It's not very scientific but when I open the case, and move my hands towards the big caps or any of the f2806 boards then it induces alot more noise in the channel my hand is close to. Not theremin-like sound but same behaviour that's for sure.
drive.google.com
(I removed the black shields for the test but when present they don't change a thing.)
===
What did I miss guys ?
(Full thread here: https://audiokarma.org/forums/index...other-protector-wont-come-off-thread.1095294/)
It's got two new F2806 boards , new power caps (with these boards: Moderator note: link to eBay removed as that would violate AK rules.
and alot of new parts on F2809. Not all caps have been replaced but more than half I would say; similar for transistors and diodes.
It works like a charm and I love it;
However - a few days into my honeymoon I realized that there's a very very noticeable humm when there's nothing playing. Loud enough that I hear it when listening to music softly and there' s a silence/gap, or even in between notes.
- That's when using the pre-amp. Even with nothing hooked to aux - I'll get the hum; and likewise when hooked to my source there's a hum.
- When disconnecting the pre-amp; it's almost un-noticeable - but as soon as I hook up something to the power amp, the very same humm appears.
I'm pretty certain it wasn't there before I swapped the big caps (which was my last job on the unit) but cannot be certain. The speakers I used to test when working on the unit are very large columns that seem to react alot less to the noise (I assume, less efficient so it's not being heard that much?) - so it *may* have been there during my pre-cap-swap testing but I'm almost 95% certain no.
When I hook them on bookshelves (Rogers Ls4a) - the humm is just so damn "loud" it's driving me crazy. (It's not 'loud' per say, but its pretty noticeable and .. annoying). I'm feeling like Alex in a clockwork orange - although instead of beethoven its that dreaded humm.
---
I'm at a loss... I don' tknow where to start debugging that. I've had tremendous of help from board members getting it to work - I cannot be thankful ever enough for it - and it seems with you guys I'm helpless. Any ideas ?
The humm looks like this:
Granted, it doesn't look like much but on small speakers its loud.
Almost the same buzz that Marty McFly experiences at the beginning of BTTF 1 when he's waiting for Doc at his house and plugs in his guitar on an overdrived amp (that ends up exploding.)
I simply can't enjoy any classical, jazz, etc. as the humm blends with the music at low levels
---
I know its foolish to try and record the sound but in case... that's me switching the spks on/off while trying to record close to the driver.
https://drive.google.com/file/d/1KB37ZXTuoq1erJLCUtiQ2srcumy4ynDN/view?usp=sharing
(Can't verify if we hear it, cause on my setup I always hear it!)
===
It's not very scientific but when I open the case, and move my hands towards the big caps or any of the f2806 boards then it induces alot more noise in the channel my hand is close to. Not theremin-like sound but same behaviour that's for sure.
PXL_20251208_230823452.TS.mp4
drive.google.com
(I removed the black shields for the test but when present they don't change a thing.)
===
What did I miss guys ?
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