Buzzing Supercap
Posted by: Dobbin on 12 November 2003
Anyone able to shed some light on why i have a mechanical buzz from my S/C??
It's there throughout the day and is beginning to irritate the hell out of me!
It's there throughout the day and is beginning to irritate the hell out of me!
Posted on: 12 November 2003 by Fisbey
I think it may be the transformer (s) - my equipment used to do this - seemed to vary - mmmm maybe a supply fluctuation - never got that annoying though.....
Posted on: 12 November 2003 by Uwe Supper
Dobbin,
where is your SC situated compared to the rest of your gear (especially compared to the preamp)?
What is your stacking order?
Cheers
Uwe
where is your SC situated compared to the rest of your gear (especially compared to the preamp)?
What is your stacking order?
Cheers
Uwe
Posted on: 12 November 2003 by Geofiz
Before things go way of on a tangent, if you have a buzzing sound in your supercap it is almost always the transformer.
There are a couple of things to check:
(1) is the bolt that holds the transformer in place secure?
(2) Are all the case screws tight?
(3) Is the hum consistent at all times or does it fluctuate in volume. If the hum is variable in sound volume then you very probably have a mains power supply problem.
(4) Are any of your other Naim components humming audibly? If so then this may also be pointing to a "dirty" mains supply to your residence.
Possible solutions:
To eliminate mechanical problems:
(1)tighten, but do not overtighten the case and transformer bolts. Torque specs are available from Naim and have been discussed on other threads on the web site.
To evaluate if the mains supply is the problem:
(1) disconnect your SC from your system and try plugging in to other plugs and circuits in your residence. If the hum is of the same character, then the problem may not lie with the internal residence wiring, but with other electrical load problems on the main electrical supply coming into your residence (something that you can not fix and the electrical utility will very probably be reluctant to admit, even correct).
(2) Take your SC along to your trusty Naim dealer. Plug it in at the shop and compare the hum level to other Naim components at the dealers. If the hum is excessive in this environment then the transformer is very probably the culprit.
Solutions:
(a) if the hum changes depending on where the SC is plugged into the mains in your residence, then put in a dedicated circuit. This will reduce/eliminate the hum and overall sound quality should increase.
(b) If the hum is consistent or worse, and still hums at the dealers, more drastic action is required. Send the SC in to Naim for the transformer to be replaced. Depending on the age, this should be a straight parts swap at little or know charge, but verify this with your dealer/Naim first.
(c) It has been suggested to loosen the transformer bolt and place the transformer on a bed of sorbothane or similar compound. I have not tried this myself, transformer/case clearance may be an issue if persuing this option as will the heat dissipation and the effect of heat on the sorbothane (if it will elliminate the hum at all).
I strongly suggest steps (a) and (b) with (c) as a last resort.
I have a similar problem with my SC and am vacilating on sending it off for transformer replacement. My SC hums noticably more than any piece of Naim gear on any circuit (I have dedicated mains too) and more than any piece my local dealer has as well. It is really only a problem at low volumes or in very quiet passages in the music, but, as you have found, it can be distractingly annoying.
Cheers and Good Luck
There are a couple of things to check:
(1) is the bolt that holds the transformer in place secure?
(2) Are all the case screws tight?
(3) Is the hum consistent at all times or does it fluctuate in volume. If the hum is variable in sound volume then you very probably have a mains power supply problem.
(4) Are any of your other Naim components humming audibly? If so then this may also be pointing to a "dirty" mains supply to your residence.
Possible solutions:
To eliminate mechanical problems:
(1)tighten, but do not overtighten the case and transformer bolts. Torque specs are available from Naim and have been discussed on other threads on the web site.
To evaluate if the mains supply is the problem:
(1) disconnect your SC from your system and try plugging in to other plugs and circuits in your residence. If the hum is of the same character, then the problem may not lie with the internal residence wiring, but with other electrical load problems on the main electrical supply coming into your residence (something that you can not fix and the electrical utility will very probably be reluctant to admit, even correct).
(2) Take your SC along to your trusty Naim dealer. Plug it in at the shop and compare the hum level to other Naim components at the dealers. If the hum is excessive in this environment then the transformer is very probably the culprit.
Solutions:
(a) if the hum changes depending on where the SC is plugged into the mains in your residence, then put in a dedicated circuit. This will reduce/eliminate the hum and overall sound quality should increase.
(b) If the hum is consistent or worse, and still hums at the dealers, more drastic action is required. Send the SC in to Naim for the transformer to be replaced. Depending on the age, this should be a straight parts swap at little or know charge, but verify this with your dealer/Naim first.
(c) It has been suggested to loosen the transformer bolt and place the transformer on a bed of sorbothane or similar compound. I have not tried this myself, transformer/case clearance may be an issue if persuing this option as will the heat dissipation and the effect of heat on the sorbothane (if it will elliminate the hum at all).
I strongly suggest steps (a) and (b) with (c) as a last resort.
I have a similar problem with my SC and am vacilating on sending it off for transformer replacement. My SC hums noticably more than any piece of Naim gear on any circuit (I have dedicated mains too) and more than any piece my local dealer has as well. It is really only a problem at low volumes or in very quiet passages in the music, but, as you have found, it can be distractingly annoying.
Cheers and Good Luck
Posted on: 13 November 2003 by Dobbin
Geofiz,
Interesting reply! I know my mains supply is not too good where we live - out in the middle of nowhere (if that's possible in Surrey!). Particulary in the winter and especially on windy nights we get fluctuations in the brightness of our lights (and in general two-three power cuts over the winter).
I'll try what you suggest.
Regarding other posts the order of components in the rack are (from the top): CDX, 252, SC, 300PS, 300, (in Mana).
Since install - Dec last year - i have moved the rack once. (I don't recall the buzz before i did this - although can't be sure and maybe I only noticed it afterwards.) The components remained in their relative positions post-move.
I suppose I'm worried that there is a fault with the box!
Interesting reply! I know my mains supply is not too good where we live - out in the middle of nowhere (if that's possible in Surrey!). Particulary in the winter and especially on windy nights we get fluctuations in the brightness of our lights (and in general two-three power cuts over the winter).
I'll try what you suggest.
Regarding other posts the order of components in the rack are (from the top): CDX, 252, SC, 300PS, 300, (in Mana).
Since install - Dec last year - i have moved the rack once. (I don't recall the buzz before i did this - although can't be sure and maybe I only noticed it afterwards.) The components remained in their relative positions post-move.
I suppose I'm worried that there is a fault with the box!
Posted on: 14 November 2003 by J.N.
Hi Dobbin
The bottom line is that the S/C has a BIG transformer and will be prone to showing up mains distortion as a physical buzzing.
Naim have tried compliantly mounting the transformer, and the sound quality is degraded.
A separate mains spur MIGHT help, but it is not a guaranteed solution.
If it is crap on the mains causing the problem; the level of the buzz should vary throughout the day, as demand on the supply changes.
I used to have 135's that made a hell of a racket in this manner. Fortunately; my local HT supply system was overhauled and the buzzing virtually disappeared.
It's all down to the quality of the supply, unfortunately.
Good luck.
The bottom line is that the S/C has a BIG transformer and will be prone to showing up mains distortion as a physical buzzing.
Naim have tried compliantly mounting the transformer, and the sound quality is degraded.
A separate mains spur MIGHT help, but it is not a guaranteed solution.
If it is crap on the mains causing the problem; the level of the buzz should vary throughout the day, as demand on the supply changes.
I used to have 135's that made a hell of a racket in this manner. Fortunately; my local HT supply system was overhauled and the buzzing virtually disappeared.
It's all down to the quality of the supply, unfortunately.
Good luck.
Posted on: 14 November 2003 by Uwe Supper
Dobbin,
have you tried to place the SC as far away as possible from the preamp?
Cheers
Uwe
have you tried to place the SC as far away as possible from the preamp?
Cheers
Uwe
Posted on: 16 November 2003 by Geofiz
Hi Dobbin,
How have you made out in narrowing down the buzzing supercap problem? Hope you have had some positive success.
Cheers,
How have you made out in narrowing down the buzzing supercap problem? Hope you have had some positive success.
Cheers,