Jump to content

Sign in to follow this  
Leeming42

Turntable buzz

Recommended Posts

I have an issue with turntable buzz as you can see from the title.

My turntable is a Project Essential 3.

My pre amp is a Rotel RC 1590. My power amp is a Rotel RB 1552 Mk II.

My speakers are B&W 683s.

I also have a Cambridge Audio Stream Magic 6 in my system no hum when I am using that.

I have tried all the usual fixes, plugging everything into the same power outlet making sure the earth is connected,  ( actally when I take the earth off the amp the humm reduces), checking for loose connections etc, Still humming. 

Any suggestions would be appreciated.

Cheers

Steve

Share this post


Link to post
Share on other sites

You connected the ground wire too?

Share this post


Link to post
Share on other sites

Yes all connected

 

Share this post


Link to post
Share on other sites

may be try swapping interconnect.

Also unplug the stream magic from the pre amp as well, so just connect the TT.

Share this post


Link to post
Share on other sites


Will give it a go :)

Just disconnected the Stream Magic, made no difference unfortunately.

Edited by Leeming42

Share this post


Link to post
Share on other sites
17 minutes ago, dwbasement said:

Also unplug the stream magic from the pre amp as well, so just connect the TT.

 

Sounds similar to a problem I was having, but in my case it was a raspberry Pi, not a stream magic.  The following is my theory and what seems to help.  The problem seems to be noise being induced into the shielding of the interconnect coming from the raspberry pi.  It is silent when playing music via the Pi, but noise is heard when using the turntable.  A better cable doesn't help as the noise in picked up in the shielding.  Best cure was route the cable from the Pi in close proximity to the earthed metal case of the amplifier.

Share this post


Link to post
Share on other sites

As above, Stream Magic, disconnected no change

Share this post


Link to post
Share on other sites
14 minutes ago, aussievintage said:

 

Sounds similar to a problem I was having, but in my case it was a raspberry Pi, not a stream magic.  The following is my theory and what seems to help.  The problem seems to be noise being induced into the shielding of the interconnect coming from the raspberry pi.  It is silent when playing music via the Pi, but noise is heard when using the turntable.  A better cable doesn't help as the noise in picked up in the shielding.

 

 

I'm surprised at this (the italicised) comment of yours, av.

 

It is certainly possible to make up - or even buy, as SGR seems to make interconnects like this - a shielded, unbalanced interconnect where noise picked up by the shield (which can certainly happen) ... is shunted to case-ground and not passed via the RCA plug to signal ground.

 

You need to use twin-ax cable - ie. 2 wires under a shield:

  • one wire is 'hot' - ie. signal.
  • the other is signal ground.

The shield doesn't connect to the RCA ground at either end:

  • at one end, use some heatshrink over the end of the shield, to stop it contacting the RCA plug.
  • at the other end, unplait the shield wires to form a pigtail which goes outside the RCA plug, to connect to that component's earth terminal (which is mains-earthed, if it uses a 3-wire power cord).

I'd offer to send you up one for audition - 'xept I know you like making stuff yourself.  :)

 

 

Andy

 

Share this post


Link to post
Share on other sites


:)

 

Share this post


Link to post
Share on other sites
2 minutes ago, andyr said:

I'm surprised at this (the italicised) comment of yours, av.

Because it was only my intention to say, better cable quality will not help. However, a different type of construction, as you say, might help.  Looking back, I was not clear, I should have said "better cable" not "a better cable", hope it's clear now.

 

 

Share this post


Link to post
Share on other sites

Can you temporarily move the TT away from the system as far as you can while still connected to see if it reduces/eliminates? Does the buzz increase with volume?

Share this post


Link to post
Share on other sites

Has the hum just started or was it always there?

Share this post


Link to post
Share on other sites


3 hours ago, Hydrology said:

Can you temporarily move the TT away from the system as far as you can while still connected to see if it reduces/eliminates? Does the buzz increase with volume?

Shifting the turntable is a good start in trying to find the cause of the buzz problem, as some times a  phono cartridge can be too  close to a mains transformer. The Rotel preamp and amplifier are  double insulated models and therefore are not earthed via the mains. The XLR  balanced option should be the preferable  method of connection between the preamp and amplifier.

 The Project turntable is supplied in optional types. Some have a mm/ line preamp fitted and this should be in the line mode if plugged into the Rotel preamps phono inputs. Also there needs to be a cable connection from the turntable earth screen to the earth lug on the preamp. The latter applies to the Project TT,s  with and without the Project phono preamp. 

Edited by VanArn

Share this post


Link to post
Share on other sites

I had a lurking hum also, I resolved it with a three pole power supply vs the standard one Pro-Ject provide. 

Edited by thathifiguy

Share this post


Link to post
Share on other sites

Thanks will give that a go 

Share this post


Link to post
Share on other sites

I had a similar problem. Tried everything conceivable, and I really mean everything, over a period of about 8 months.

I came across this on a forum, and it has worked for 2+ years:

I wrapped the end of a wire around the outside of the wall wart power supply connector that goes into the turntable, and the other end on the phono stage ground post (which it shares with the turntable ground wire).

Presumably a grounding/ground loop problem, tho I don't know for sure.

An inexpensive possible solution to try.

 

 

IMG20200223063518.jpg

Edited by andrewinbriz

Share this post


Link to post
Share on other sites


Cheers, now have a couple of things I can try. Fingers crossed

Share this post


Link to post
Share on other sites
14 hours ago, Ozcall said:

Has the hum just started or was it always there?

Was originally running the turntable through the Stream Magic via a Toslink cable, was not noticing the noise at that point. Put the Pre amp in the system in November and the buzz started. Disconnected the ground wire from the preamp and the buzz reduced but is still there at volume. Cannot hear it when an album is playing. Buzz increases with volume. 

Share this post


Link to post
Share on other sites

Can you confirm that your version of the Project Essential  III is the Recordmaster, which has a USB output as well as the stereo rca sockets with  the  line or phono level  switching  option?

The Stream Magic,  I believe, uses a 3 pin IEC  power lead and if this is left in the system, it is possible that  your problem could be an earth loop via the USB cable, if these are left connected to form a loop. The ground wire from the turntable should connect to the earth on the preamp and not left disconnected as it screens the pickup arm.

 

Edited by VanArn

Share this post


Link to post
Share on other sites

Hi thanks for the input. There is no USB lead connected. The Turntable is an Essentials 3 digital, I use to run it through the Stream Magic via a Toslink cable with the Stream Magic switched to pre amp mode, using the built in phono stage on the turntable. I have now switched the Stream Magic off the pre amp setting, added a Rotel pre amp, taken out the Toslink cable switched the built in pre amp off, and connected the turntable to the pre amp the RCA leads. I disconnected the ground wire from the earth on the pre amp as it increased the hum.

Share this post


Link to post
Share on other sites

Finally fixed. The Rotel amps can be connected via a small wire, which then allows you to use a trigger switch so that both the pre and power amp, can be turned on simultaneously with the remote supplied with the power amp.. Disconnected the wire, no more hum.  Happy days. Thanks for all your suggestions guys

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

  • Classifieds Statistics


    Currently Active Ads

    Total Sales (Since 2018)

    Total Sales Value (Last 14 Days)

    Total Ads Value (Since March 2020)
  • Recently Browsing   0 members

    No registered users viewing this page.


×
×
  • Create New...