Intermittent Buzzing sound from TT

[Mayank Shah]

Hooked up Project Primary TT to Rega amp phono in. Records play fine but there is an intermittent buzzing sound which comes for a few seconds and disappears. This time the music is crystal clear, then after a few seconds again a faint buzzing sound.

Project TT has inbuilt RCA chords with an earth cable. Have connected this to the earth screw at the back of the amp and another wire to the earthing at the mains supply. Don't understand how the Rega earth works as the Rega power chord has only 2 leads.

Tried with and without cover/fan....checked earthing with meter and lamp. Home earthing is fine. Other inputs on the amp are fine.

Records and stylus properly cleaned. This regular intermittent buzzing is really really annoying.

Edit: Forgot to mention that the buzz is still there even when I tried using 2 different external phono stages sweetly loaned by FM @celester340 .

It's not a loud or scare the shit out of you kind of buzz.....but mild buzzing....more of some kind of interference thing but at fairly regular intervals.

 

[audiopro]

Hooked up Project Primary TT to Rega amp phono in. Records play fine but there is an intermittent buzzing sound which comes for a few seconds and disappears. This time the music is crystal clear, then after a few seconds again a faint buzzing sound.

Project TT has inbuilt RCA chords with an earth cable. Have connected this to the earth screw at the back of the amp and another wire to the earthing at the mains supply. Don't understand how the Rega earth works as the Rega power chord has only 2 leads.

Tried with and without cover/fan....checked earthing with meter and lamp. Home earthing is fine. Other inputs on the amp are fine.

Records and stylus properly cleaned. This regular intermittent buzzing is really really annoying.

Edit: Forgot to mention that the buzz is still there even when I tried using 2 different external phono stages sweetly loaned by FM @celester340 .

It's not a loud or scare the shit out of you kind of buzz.....but mild buzzing....more of some kind of interference thing but at fairly regular intervals.

Turn off any lights in the room. Especially led ones. Then see what happens. If it doesn't work connect the ground wire to the amplifiers Ground point on the chassis if it has one or to any screw on the amplifier chassis. See if that works. Also keep phono wires away from power cables.

 

[Rupakghosh.80]

Earthing problem for sure

 

[Mayank Shah]

Checked all electrical fittings. Found a loose connection on the earth lead on the TT itself. Opened up the back plastic cover plate and tightened the earth lead. Thank God it's ok now.
Edit: Did not have to connect home earth to amp chasis, only the earth lead from the TT output cable. I am sure there is a way to upgrade that if required.

 

[raghupb]

Faulty or weak grounding can cause this behavior in components.
Very sensitive in analog equipment, TTs, tube equipment, etc.
I have a similar issue that I'm trying to chase down.
It is constant and only evident when the system is not playing (like between tracks).
Does not happen with my regular rig.
Another FM swears that he can hear HF ringing in my speakers; I can't (thank God).
We nailed it to the start of fridge compressor in my case.
Cheers,
Raghu

 

[Mayank Shah]

I think I spoke too soon....the intermittent buzzing is still there. I now tried connecting the amp chasis to home earth but still. I guess either it's some electrical/electronic appliance or the TT itself. Switched off all home appliances and even all WiFi devices (much to the chargin of the family) the issue is still there.

 

[rikhav]

Are the interconnect cables shielded ?
From the TT

 

[Mayank Shah]

Are the interconnect cables shielded ?
From the TT

Yes.

 

[swamytk]

To isolate main supply and its earth, you may try connecting both TT and Amp to any fully charged UPS. Ensure that UPS mains is not connected. So your system will be totally isolated from rest of electrical line at home. You don't need high power UPS. A basic PC UPS also will do if you can do this test keeping Amp volume low.
Though I am not an expert If it is me I would have tried this way.

 

[raghupb]

To isolate main supply and its earth, you may try connecting both TT and Amp to any fully charged UPS. Ensure that UPS mains is not connected. So your system will be totally isolated from rest of electrical line at home. You don't need high power UPS. A basic PC UPS also will do if you can do this test keeping Amp volume low.
Though I am not an expert If it is me I would have tried this way.

Basic PC UPS may not work, it is modified sine wave.
Cheers,
Raghu

 

[audiopro]

I think I spoke too soon....the intermittent buzzing is still there. I now tried connecting the amp chasis to home earth but still. I guess either it's some electrical/electronic appliance or the TT itself. Switched off all home appliances and even all WiFi devices (much to the chargin of the family) the issue is still there.

Mayank

Turn off all LED lights in the house. They emit interference from their power supplies. I said connect the TT earth to the amp chassis. Not home earth. Your amp should already be grounded or it may use a floating ground. What amp and CD player do you have? Does the back of the amp IEC connector have three pins or two? I think you mentioned that the Rega has only two pins. In that case it will float the ground via the interconnects to the next grounded component via the interconnect, which could be your CD player. Does your CD player or DAC have three power pins? If yes, see if turning on the dac power while playing the tt helps reduce the noise.

 

[Mayank Shah]

Connecting the home earth either to the amp or the TT earth lead does not do anything. Rega amp has a floating ground, hence a 2 prong power cable only. As others have said, need to check with all the lights off and also to run TT solely off a ups. Traveling now, will post soon. What happens when I find a faulty led light?

 

[Mayank Shah]

Mayank

Turn off all LED lights in the house. They emit interference from their power supplies. I said connect the TT earth to the amp chassis. Not home earth. Your amp should already be grounded or it may use a floating ground. What amp and CD player do you have? Does the back of the amp IEC connector have three pins or two? I think you mentioned that the Rega has only two pins. In that case it will float the ground via the interconnects to the next grounded component via the interconnect, which could be your CD player. Does your CD player or DAC have three power pins? If yes, see if turning on the dac power while playing the tt helps reduce the noise.

A little lost here, what has my cdp and dac have to do anything with the TT? Rega IEC has 2 pins only. Amp has an earth screw at the back.... unfortunately that's not helping the interference. Will check with all appliances off.

 

[audiopro]

A little lost here, what has my cdp and dac have to do anything with the TT? Rega IEC has 2 pins only. Amp has an earth screw at the back.... unfortunately that's not helping the interference. Will check with all appliances off.

Cdp will help with grounding. If your rega Amp isn't grounded it uses the rca ground. It's called floating ground. But for that your Cdp should be three pinned and should be turned on.

 

[Mayank Shah]

Cdp will help with grounding. If your rega Amp isn't grounded it uses the rca ground. It's called floating ground. But for that your Cdp should be three pinned and should be turned on.

That would be the same thing as connecting the home earth to the amp chasis no? Still not getting the point of the CDP in the picture here. Marantz cd6006 which I have has 2 prong only.

 

[Hari Iyer]

I had similar problem of noise with my Thorens TT. It originally had a single core shielded wire which connects with the cartridge. So one point of the cartridge becomes the ground. I changed this by making the cable 2 core shielded wire. Now the two cores connects the cartridge and the shield is grounded to my preamp powers supply ground. This removed all noise for me

 

[audiopro]

That would be the same thing as connecting the home earth to the amp chasis no? Still not getting the point of the CDP in the picture here. Marantz cd6006 which I have has 2 prong only.

Read up on floating ground. You'll get the picture. Marantz also uses floating ground so anyways this wont work. See what Hari has to say. He is very good with these things.

 

[Mayank Shah]

Hello all, Would a separate 3 core line from the mains, exclusively for the audio setup make a difference?

 

[rikhav]

If you have 3 phase electrical connection dedicate one phase only for audio and yes that also means a dedicated new line

I am not sure if humming issue will.be solved or not but overall noise floor In all equipment will surely reduce.

 

[jls001]

Intermittent buzzing doesn't seem to be grounding issue. Ground loop issues would manifest as continuous hum (fairly loud). If your Rega amp uses two pin IEC socket it means the amp is double shielded (like DVD players or CDPs). The ground wire from the TT despite being connected to the grounding pin of the amp or amp chassis is not eventually earthed because the amp's output is to the speakers (and speakers are floating w.r.t. ground).

In case you had already tried switching off other electronic devices (especially those powered by SMPS) in your room but the buzzing persists, may be you should schlep your TT to a friend's place and try it out in a different environment to rule out the TT itself.

In Rega arms the negative lead of left channel (blue wire) doubles up as grounding wire for the TT. Sometimes if you simply jumper a thin conducting wire from the left channel of the barrel of the phono input socket of the amp (or phono preamp), to a ground point, it is as good as a dedicated ground wire from inside the tonearm's tube. I use this trick to provide grounding to both the tonearms on my TT because both arms use wooden arm tubes..

Get yourself a cheap, Rs 500 multimeter (yeah, we have to be our own handymen if playing the TT game because regular electricians can't help us troubleshoot such issues) and check if your electrical ground is okay or not. How to do it: Put your multimeter in the lowest AC voltage mode (good ones will have lowest range of 0.2 Volt AC) and measure the AC voltage between the neutral and ground of your wall socket. Ideal value must be zero but is never zero. Upto 0.4 or 0.5V AC is acceptable. If it is higher then your electrical grounding is not effective enough.

Also, re-route the TT cable as far away as practically possible from power cords (never run them parallel, and if they must cross, cross them at or near right angle) and audio equipment (esp must be kept away from transformers of audio equipment). TT cables are shielded but despite that they are very prone to picking up noise from nearby gears because they carry very tiny signal.