Question Hum/buzz from speakers/headphones with no sources connected.

jonnywaugh66

Novice Member
Audiolab amp - silent, Naim and Rega buzz/hum through speakers and headphones with or without sources connected. Naim buzz/noice reduced with ground plug wired to grounding point on amp, especially on phono input but not eliminated. Rega, no difference when grounded and the buzz/hum is especially loud with Phono input (Rega TT).

All this is bafalling, 3 new quality amps with 3 different results all in the same setting. I have isolated each component and connection, taking the Rega to a room far way from any likely ground loop, no change.

My hi fi man is baffled! Every suggestion on ground loops has been exhausted, mains conditioner, setting (rooms), connections, cables, speakers, Wi Fi power line disconnected, all no change.

HELP please, anyone?
 

jonnywaugh66

Novice Member
Sorry, I also should have said, an old Ferguson cassiever, Yamaha amp and old Audiolab in the same set up didn’t have this problem, in fact the Yamaha was absolutely dead silent! The Rega and Naim also emitt some noise from the units themselves.
 

Oasticles

Active Member
I have a very similar problem with a new Rega Brio amplifier. Angry wasp type buzz that isn't volume dependant on all inputs other than the phono stage. With the phono increasing the volume results in a commensurate increase in the buzzing.

Appreciate that the causes are multifactorial but once you hear it, it's like an ear worm, ie you can't unhear it!

Have to say mine is audible only when up close to the speaker so no doubt the manufacturer would likely conclude it's within the manufacturing tolerance. Just interested on others thoughts as to what you feel is an acceptable level of noise or if silence should be the expectation?
 

Gray3

Active Member
I have a very similar problem with a new Rega Brio amplifier. Angry wasp type buzz that isn't volume dependant on all inputs other than the phono stage. With the phono increasing the volume results in a commensurate increase in the buzzing.

Appreciate that the causes are multifactorial but once you hear it, it's like an ear worm, ie you can't unhear it!

Have to say mine is audible only when up close to the speaker so no doubt the manufacturer would likely conclude it's within the manufacturing tolerance. Just interested on others thoughts as to what you feel is an acceptable level of noise or if silence should be the expectation?
No manufacturer would say that an 'angry wasp type buzz' was within their tolerance 🙂
Yes, silence is a reasonable expectation.
 

Oasticles

Active Member
Thanks - I'm going to see if changing a few things will help (positioning of amp, power block, new grounding cable etc). If no improvement I'll go back to the dealer and ask that they take a look at it.
 

noiseboy72

Distinguished Member
Worth looking at things like dc blockers and isolating transformers. Have you measured the mains voltage and potential between neutral and earth?

My guess is there's high harmonic distortion on your mains feed, but without scoping it, it's impossible to tell.
 

Oasticles

Active Member
Worth looking at things like dc blockers and isolating transformers. Have you measured the mains voltage and potential between neutral and earth?

My guess is there's high harmonic distortion on your mains feed, but without scoping it, it's impossible to tell.
Haven't gone down that route yet as I didn't have the issue with my ancient NAD amp. I guess that different equipment has different sensitivities to the things you mention. Plus frankly I think I would be out of my depth knowing what was science vs snake oil!
 

noiseboy72

Distinguished Member
When it comes to removing hums and buzzes, it's really whatever works - and doesn't make the sound worse!

When I was designing audio equipment, we used to have a box that added harmonic distortion and buzzes to a mains line. It was basically a poorly wound isolating transformer and some high power inductors that created a horrible slightly tuned circuit. It made any bit of kit sound worse, so we used it to design power supplies that rejected the interference. This was mainly on high speed cassette copiers that were sent all over the world and used in very dubious locations making educational tapes, so the ability to work well on poor mains was of importance.

A good hifi shop should have a tame electrician who can scope out the mains and see if there is an issue with it. Lots of LED lighting, switched mode power supplies in IT equipment and heavy inductive loads on the same supply can all have an effect, so it's worth checking for. If there's DC present on the line, then a basic isolating transformer will get rid of this, while high harmonics can only really be cured either by total signal regeneration or complaining to the supply company until they fix it at their end!

Your basic domestic sparky probably won't have much experience of this, as it's not really covered in the basic syllabus, but an electrical engineer should be able to render more assistance.

As you rightly say, it's down to the design of the equipment and the filtering and power supply type employed. Naim power supplies do have something of a reputation for being a bit picky about supply voltage and stability, but I've no info on the Rega.
 

larkone

Distinguished Member
 

Oasticles

Active Member
Thank you - my issue is the buzz eminates from the speaker, particularly from one channel (ie I can move it from the left to right speaker if I swap over the speaker cables) so different from the post you kindly referred to.
 

larkone

Distinguished Member
Search the Naim forums, plenty of people are reporting issues with hum from Naim amps being heard through the speakers, however if it is only one identified channel then it points to a fault in the amp.
 

Oasticles

Active Member
So have tried an old NAD 314 amp keeping everything else the same (sources, power, interconnects etc) and it’s silent unless the volume knob is turned up full. Suggests it’s unfortunately an issue with the Rega. Will see what the dealer says.
 

jonnywaugh66

Novice Member
Since my original post I spoke with someone at Rega, they said it could have taken a knock in transit so my great local dealer sent me another but it also buzzes. I started the elimination process again and set up an old Rotel amp but no buzz, dead silent. I took the Rega to an empty property, same buzz. I did notice on the 2nd Rega that the buzz is more noticeable on the right channel.

I love this amplifier, it has just a lovely sound, so easy to relax with but as Oasticles says, the buzz is like an earworm and I don't think it is acceptable, if a load of other amps, new and old don't buzz why does the Rega, and to be fair a Cyrus One HD and Naim Nait XS 3?
 

Oasticles

Active Member
Sorry to hear you are still having issues. I ended up returning the Rega. The dealer couldn’t replicate the issue I was having but were good enough to refund me. I have ended up with a Music Fidelity M2si. Happy to report that it’s silent and whilst different from the Rega I am enjoying it.
 

jonnywaugh66

Novice Member
Sorry to hear you are still having issues. I ended up returning the Rega. The dealer couldn’t replicate the issue I was having but were good enough to refund me. I have ended up with a Music Fidelity M2si. Happy to report that it’s silent and whilst different from the Rega I am enjoying it.
Glad you are sorted, how different is the MF, it's on my list but I can't compere with the Rega as it's on loan and the dealer doesn't stock the MF.
 

Oasticles

Active Member
I think there’s a review on AVF that will no doubt be more insightful than my comments! In summary it does what an amp should do ie it gets out of the way of the source and drives my speakers (B&W 606’s) really well. I think the extra power provides a bit more low end but wouldn’t say it ’colours’ the music in any way.

As you probably know it really is a simple amp - no headphone, phono stage, digital / BT etc.

I‘m using it for vinyl via a simple phono stage, Rega Apollo CDP and Sonos Port for Spotify. To my non-audiophile and old ears it sounds good.
 

w0z

Member
Although not helpful in this instance I would say that if you apply shorted inputs to the amp and switch off as much as you reasonably can in your home (anything with a switch mode supply which might radiate for example indoor mobile telephone) and the buzz persists then you aren't going to easily solve it. You shouldn't need to use mains filtering and anti-surge devices if your supply is OK although I would always have anti-surge on any expensive electronic equipment as a matter of course.
 

jonnywaugh66

Novice Member
Although not helpful in this instance I would say that if you apply shorted inputs to the amp and switch off as much as you reasonably can in your home (anything with a switch mode supply which might radiate for example indoor mobile telephone) and the buzz persists then you aren't going to easily solve it. You shouldn't need to use mains filtering and anti-surge devices if your supply is OK although I would always have anti-surge on any expensive electronic equipment as a matter of course.
Thanks but have tried the Rega in an empty propery, no appliances, routers not even a tv, nothing and it still buzzes.
 

jonnywaugh66

Novice Member
I had that with my new preamp. Even moved it to another room at it still buzzed. No buzz previously with same AVR, power amp and sources. Sent it back to the manufacturer and got a new one. Same buzz.

I bought theses this week and now no buzz


Did you buy both items and if so have you tried one without the other?
 

JUS

Well-known Member
I thought you might ask that. No not tried them individually. I only got them on Wednesday and put them both in together in desperation. I’m pretty sure it was the power cable that did the trick though. I bought that mains cable due to this bit in the spec

“The cable we use for the No. 11 power lead is oxygen free copper 2.05mm diameter with a built in ground loop filter to trap mains noise at the plug end not the equipment end. “

Im not an electrician and not affiliated with MCRU. All I can say is I was going to send the preamp back a second time, this time for a refund as it was driving me nuts, I could hear the hum walking into the room or in quiet scene.

I’ll take out the plug and see if the hum returns over the weekend

I think MCRU do 30 day returns..and I used a 10% discount code, MCRU10 o think it was. So you could just send them back if it doesn’t fix it for you.
 
Last edited:

jonnywaugh66

Novice Member
I thought you might ask that. No not tried them individually. I only got them on Wednesday and put them both in together in desperation. I’m pretty sure it was the power cable that did the trick though. I bought that mains cable due to this bit in the spec

“The cable we use for the No. 11 power lead is oxygen free copper 2.05mm diameter with a built in ground loop filter to trap mains noise at the plug end not the equipment end. “

Im not an electrician and not affiliated with MCRU. All I can say is I was going to send the preamp back a second time, this time for a refund as it was driving me nuts, I could hear the hum walking into the room or in quiet scene.

I’ll take out the plug and see if the hum returns over the weekend

I think MCRU do 30 day returns..and I used a 10% discount code, MCRU10 o think it was. So you could just send them back if it doesn’t fix it for you.
Did you try one without the other in the end? Thanks, I would love to hear the outcome.
 

JUS

Well-known Member
In my setup Ive discovered it’s a pretty complex situation. Quite a few things seem to be adding hum.

the biggest cause is a network switch. I discovered if I moved it from a wall socket to a extension lead the hum reduced significantly but wasn’t cut out completely. I literally pulled every power cable out only leaving AVR, Preamp and power amp and I could still hear hum emanating from preamp and my speakers.

i chucked some more money at the problem and bought one of these


Behringer MICROHD Hum Destroyer HD400​


The hum disappeared from my front l&r speakers I connected it to but hum still from preamp. I then, by accident, pushed down on my preamp and the hum from the preamp significantly reduced. So I’ve now put a few weights on the top of my preamp and I’m pleased to say no audible hum in over a week.

I can’t help think I’m hiding the problem and not resolving the cause. Perhaps I need a better ground or something.....the power cables, behringer and weights all help. If I remove one of them a hum returns.
 
Last edited:

The latest video from AVForums

Movies Podcast: Star Trek in 4K. Is the new boxset worth it?
Subscribe to our YouTube channel

Latest News

T+A announces high end 200 Series audio components
  • By Andy Bassett
  • Published
Trinnov Altitude update adds new features
  • By Andy Bassett
  • Published
Panasonic TVs welcome Disney+
  • By Andy Bassett
  • Published
Audio Research announces I/50 integrated valve amp
  • By Andy Bassett
  • Published
Loewe confirms return to luxury TV market
  • By Andy Bassett
  • Published

Full fat HDMI teeshirts

Support AVForums with Patreon

Top Bottom