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Hi All,
I lurk daily but seldom post and really don't have a clue to what I am doing. My problem, and it has been going on for some time now, is I am getting what I guess is radio music over my turntable. It also has a lot of what sounds like static or ground loop most notable when the volume is turned up and no record playing but you can make it out at low volume. You can look at my system here on the asylum but in short:
Thorens 309 turntable
Jolida JD9
Denon 103
Cary SLP98 pre
Conrad Johnson MV 60SE amp
This has really affected my listening experience and would appreciate any advice on fixing this.
Thanks in advance for any help or suggestions,
Doug
Follow Ups:
Thanks to all for the help.
I got the Blue Jeans cables today and installed them from the turntable to the Jolida. They seem to help a little, but the problem is still there. I have excessive noise over the turntable and can hear what I believe is radio or maybe TV commentary not to mention what sounds like static or a ground loop. I am wits end on this and might just have to give up on the turntable. It might be the cartridge, Denon 103, but I don't have the funds to endlessly search this out. Any help would be appreciated but buying $1000 interconnects is not an option.
Thank you,
Doug
nt
We don't shush around here!
Life is analog...digital is just samples thereof
No, I am not close to any towers radio or television.
Doug
What a great collection of ideas. THANK YOU!!
Thanks to everyone who has responded to my post. It seems from all the answers that first I will try a new set of shielded interconnects. Looking at the Blue Jeans Cable LC-1 that actually fits in my budget. If that doesn't work will try some of the other ideas.
Doug
That I found on Amazon: RF Shielding Fabric .
If is 40x40" and affordable. You might be able to position something like this to help block the offending signal.
Ed
We don't shush around here!
Life is analog...digital is just samples thereof
One other thing, ypur phono stage should have grid stoppers already installed, if not then they could be added. Grid stopper will be a small resistor soldered closely to the grid of the triodes.
I have had this problem-
Typically it comes from a few things that add up to RFI - Radio Frequency Interference
You are close to a transmitter (FM)
Your Phono stage has great gain
To fix - two items - but #1 should fix it-
#1: Ferrite - You will want to install a pair (one for each channel) of Ferrite beads on the signal (HOT) wire for each channel somewhere between the TT and the 1st gain stage in the Pre-amp ( i installed it after the RCA jacks in my pre-amp)
#2 Shielded interconnects between the TT and pre-amp - I like a cable with a braided shield that has at least 95% coverage and is under 25pF/foot. Also make sure that the shield is terminated at both ends.
Happy Listening
Many vinylphiles have. The shielding on your ICs (either the ICs from the turntable to the phono preamp or from the phono preamp to the line stage) is insufficient to prevent the electromagnetic radiation pickup.
Do you live close to a radio station transmitter? Check your neighborhood for radio towers and power lines. I once had a problem where there was an intermittent frying type noise on my Denon DP-62L/phono preamp hookup. I tried everything that I could dream up but the only thing that fixed it was when I moved.
Currently I have a very low level hum that I am picking up. I have tried all sorts of things and I was beginning to think it was a ground loop. I proved where it was by disconnecting the phono leads from phono preamp and placing rca caps over the inputs. The hum disappeared, so it was being picked up from the phono leads or the tonearm.
I own a VPI Prime and hum pickup is not common, so I looked at the phono leads. Initially I was using a set of Kimber Heros w/WBT RCA connectors for the phono lead. I replaced that with a set of Audioquest Leopards and the hum picked dropped greatly.
Its not gone but it can be tamed with a better phono lead. I may invest in a better shielded phono cable in the near future but the level of the hum is very low so its not a critical problem now. Your problem is similar.
You are picking up something other than hum but it is electromagnetic interference. The only way to isolate your setup from the problem is with better shielded phono leads (or the ICs between the phono preamp and line stage). You have to remove or cut down on the amount of interference you are picking up.
Remember that the phono preamp is a device that has lots of gain. You can pickup all sorts of interference if you don't isolate your connections. Its a tough problem but not an impossible one to solve. Just concentrate on finding a better shielded connection between your turntable and your phono preamp (it still could be the IC between your phono preamp and your line stage but your turntable leads are a better bet).
Ed
We don't shush around here!
Life is analog...digital is just samples thereof
interconnects from my Lehmann Black Cube phono pre to the aux inputs on the front of my Denon receiver. A Pioneer PL-50 turntable was connected to the Lehmann Black Cube with its built-in interconnects and ground cable.
I wrote to Kimber, and their response said nothing about the unshielded PBJ cable. Instead, he told me to check that the RCA connectors were clean with no corrosion. He stated that corroded cable connections could make the interconnect act like an antenna.
Well, I cleaned all the connections with no improvement. I then tried shielded interconnects from the Black Cube to the receiver, and the interference was cut in half but not eliminated. That was the end of my experimentation. Also, I never get radio interference when my turntable audio and ground cables are connected directly to the phono and ground inputs on my receiver.
You talk about two different systems. (1st) CJ preamp/JD9phono, (2nd) Denon receiver/Pioneer turntable/Black cube.
What system has the radio problem?
Read much? Two people, two posts, two systems.
"Read much? Two people, two posts, two systems."
Thank you for pointing out my error, I don't know what I would do without you ...
nt
nt
I am merely relating my experience with a stereo system picking up unwanted radio signals like bewareofdoug is experiencing. In my case, the receiver is in phono mode not radio. In bewareofdoug's case, he doesn't have a radio in his stated setup. Yet, we both are receiving stray radio signals through some component or interconnect.
Sounds to me like RFI. Are your cables shielded? More than likely the radio signals are entering through unshielded cables. Just a thought.
G'day all, try the effect of ferrite 'clamp on' chokes. They can be very effective at supressing this kind of RF (radio frequency) breakthrough. Try placing them on different leads to see where they work best. Regards, Felix (vk4fuq).
It could be the needle or cartridge on the turntable has gone bad. Try replacing it with a cheap new one and hear what happens.
Shorting plugs might fix the problem. Take a look.
...I have had a similar situation with a reel-to-reel setup some years ago. It eventually went away so I never had to find a cure or find out why it had happened.
Later Gator,
Dave
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