BUZZING PROBLEM WITH TURNTABLE-Please Help!

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My turntable has a buzzing noise when a I turn the volume up about 1/4 way and gets worse as the volume increases. I did replace the stock rca cables with another brand (Scosche EFX double shielded) I also moved the phono pre-amp further away from tt, and used another outlet for the ac plug, but still have buzzing. If my memory is not mistaken, I dont remember hearing this buzzing prior to changing the stock rca cables, but i'm not 100% sure. Just wondering if the new cables could be causing the noise. Any suggestions to what I can do or check to make the buzzing noise go away?

Thanks!!!
 
analog_sa said:
More info needed. Is the arm grounded? What is the tt? How did you replace the cables? Pictures?


Hi analog_sa,

The tt is short for Turntable. As for the cables, I just solder the new ones I had purchased and added a single 14awg for ground. I tried everything I could think of to get the buzzing noise to stop, but still there. Here is what I did: I unpluged the amp, turntable, and phono pre-amp. I used a seperate house outlet, that didn't have any other sources running off of it, and pluged only the mentioned audio components on that line. I still had the buzzing noise. I tried removing the rca cables that run from the turntable to the phono pre-amp and the noise was totally gone. Could this indicate a problem being somewhere from the cables and the turntable? Here is a photo: http://img138.imageshack.us/my.php?...pict0462wn2.jpg

Thanks
 
The pictures make everything very clear. As long as your new cables grounds are indeed connected to the gree and blue wires coming from the arm all should be fine. As long as the new cables are shielded there should be no difference from the old ones. It is of course possible the problem existed with the old cables.

Does the hum go down when the grounding wire is connected? You don't mention the phono pre type but it's entireley possible its grounding scheme is to blame. You can try attaching the grounding wire to either the left or right channel rca grounds instead of the grounding post of the pre. You can also do this by soldering a link between ground and either the black or green wire of your cables on the tt board. Finally you may try lifting the AC power ground of the tt if used.
 
analog_sa said:
The pictures make everything very clear. As long as your new cables grounds are indeed connected to the gree and blue wires coming from the arm all should be fine. As long as the new cables are shielded there should be no difference from the old ones. It is of course possible the problem existed with the old cables.

Does the hum go down when the grounding wire is connected? You don't mention the phono pre type but it's entireley possible its grounding scheme is to blame. You can try attaching the grounding wire to either the left or right channel rca grounds instead of the grounding post of the pre. You can also do this by soldering a link between ground and either the black or green wire of your cables on the tt board. Finally you may try lifting the AC power ground of the tt if used.

Hi analog_sa, I was just about to try and change the interconnects out and try putting the oem's back in to see if it makes a difference. Also, I noticed that when the power button is off, my cartridge still picks up my finger as I gentley rub it. I thought that when the power was off, that the cartridge should not pick up anything! Also as you mentioned about disconnecting the ground from the pre-amp, when disconnected, the buzz becomes really loud. I will try and connect a jumper wire from the ground to the black or green and see if that helps. As far as lifting the AC power ground, I am really not sure what you mean.

Thanks Again!
 
Was ground there before buzzing?

That large ground wire.. did you add that before the buzz (ie is that something you added along with the new phono cable)?
Looking at the colours of the tonearm wires you have (starting from Left) green red blue white.. looking at the Phono cable the black from the phono cable goes to green on the tonearm cable, the red goes to red, the green on the phono goes to blue on the tonearm and white goes to white... Is this how it was wired originally?
can you with a multimeter find out where the small tonearm wires go?
Or can you verify where they go on the cartridge?
The other thing.. Can you make the exposed coloured leads shorter where they are soldered to the board so that there is more of the sheilded section(the thick black sheath) right up to the board?
Have you checked your soldering for small dags connecting the other tracks?
Keep me posted
Good Luck
 
FSHZ:42 said:


Also, I noticed that when the power button is off, my cartridge still picks up my finger as I gentley rub it.


This is very normal. Most turntables do not mute the catridge when powered off.


I find it very stange that there are AC carrying wires so close to the unshielded terminations of the tonearm wires. Surely this is a way for hum to get in.
 
I dont remember hearing this buzzing prior to changing the stock rca cables

Well then there must be something different or you left off a jumper from the chassis to the ground from your cartridge.

Take your VOM meter and find the hot terminal on each old RCA cable and jot down the color. Disconnect the new cables and do the same with them and check to see that color for color there is a match up. Sometimes cable manufactures will use different color combinations and therefore the colors don't match between the new cables and the old. You will need to see if the "HOT" on each cable makes connection to the "HOT" for each channel on the cartridge. Find the ground for each channel tie them together and make sure they ground to the chassis.

Do NOT lift the AC power ground as this is a safety matter and must be observed. Note* If it was quiet before with the AC connected as it is there is NO need to screw with it.
 
O.K. I found out that the left channel was on the right side of turntable solder board. both grounds were soldered correct. Could this have been making the buzzing sound? I went ahead and desoldered the EFX interconnect cable and replaced it with the oem cable. It appears that the buzzing is going. I did notice that when the volume is turned up like around 3/4 way & up, you can hear a hissing sound. Any suggestions as to maybe getting another good interconnect cable?
 
I was also wondering if any of you guys, by looking at the components on this Denon turntable, would be able to recommend any type of upgrade like replacing any of the caps, resistors, or what not, that would improve its sound! Also, take a look at my phono pre-amp and let me know if this also can be upraded. I noticed on the power plug jack, that the earth ground isn't connected to anything. Is this O.K.? Thanks again everyone for your help! Here are 2 photos of the pre-amp:

http://i173.photobucket.com/albums/w52/gammaray1965/ParaSoundpic4.jpg

http://i173.photobucket.com/albums/w52/gammaray1965/ParaSoundpic2.jpg
 
Perhaps better equipment

Without patronising you at all, perhaps upgrading the turntable/ phono section may be in order. I dont know what other members think but will read with interest. If you have a budget to upgrade it might be better spent. Modifying stuff that works as in the phono preamp may well result in degradation of sound or it may stop working all together. Those op amps are soldered to the board for instance and may be difficult to get out if you are not experienced.. I dont like metal film resistors etc etc but perhaps leaving it alone and upgrading to a tubebox se or some such device by "project" may make you happy.
Nick
 
Perhaps better equipment

Without patronising you at all, perhaps upgrading the turntable/ phono section may be in order. I dont know what other members think but will read with interest. If you have a budget to upgrade it might be better spent. Modifying stuff that works as in the phono preamp may well result in degradation of sound or it may stop working all together. Those op amps are soldered to the board for instance and may be difficult to get out if you are not experienced.. I dont like metal film resistors etc etc but perhaps leaving it alone and upgrading to a tubebox se or some such device by "project" may make you happy.
Nick
 
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