AVR buzz/hum - what can be done

[avesatani]

Well the quality is due to the poor headphones. Do you know someone who has a good pair of headphones, so we can be sure it is the power amp section picking up the buzz.

Alternatively you could just go ahead and install the RF blockers. They are cheap.

What should i buy and how to install that ?

 

[TLS Guy]

What should i buy and how to install that ?

You need to buy one of these for each speaker.

We had a member having a Spanish language radio station coming loudly though all his speakers this last July. This was being picked up in his speaker leads. He was not able to build the rejecter blockers specific to the frequency of the offending radio station I designed for him, so I built them for him.

You will not need a cap I don't think, just the inductor.

So if indeed the pickup is in the speaker leads, which is most likely, that will do the trick for you.

 

[avesatani]

You need to buy one of these for each speaker.

We had a member having a Spanish language radio station coming loudly though all his speakers this last July. This was being picked up in his speaker leads. He was not able to build the rejecter blockers specific to the frequency of the offending radio station I designed for him, so I built them for him.

You will not need a cap I don't think, just the inductor.

So if indeed the pickup is in the speaker leads, which is most likely, that will do the trick for you.

OK, I'm not sure how and where should i install those ?
Cut the cable and connect the wires on each side and do the same with other part of the cable which
then extends to the speaker connectors ?

Another question on the topic, recently there was a 5G upgrade of the nearby GSM tower, could that be the cause of the interference ? Did some research when was the 5G installed and it was around the time i've started to notice the buzz. ( no, i'm not implying on any of 5G conspiracy theories )

 

[TLS Guy]

OK, I'm not sure how and where should i install those ?
Cut the cable and connect the wires on each side and do the same with other part of the cable which
then extends to the speaker connectors ?

Another question on the topic, recently there was a 5G upgrade of the nearby GSM tower, could that be the cause of the interference ? Did some research when was the 5G installed and it was around the time i've started to notice the buzz. ( no, i'm not implying on any of 5G conspiracy theories )

That upgrade could certainly be the cause, and probably is, yes. In which case we might have to design a tuned circuit for the carrier frequency of that tower. I have never designed for that eventuality, so it would require some research. How close are you to that tower? Transmitting towers are actually a common cause of what you are experiencing. I expect one of the upgrades was to increase the power.

The inductors go in series with the +ve wire to each speaker at the +ve terminal of your receiver.. To avoid shorts I recommend you use that terminal strip like I did and wrap it with electrical tape. Try that first. It may do the trick. If not a tuned RF rejecter circuit will have to be designed for that tower.

 

[avesatani]

The tower is around 100m from my place.

 

[TLS Guy]

The tower is around 100m from my place.

So that nails it down. That is your problem. So try the inductor, if that does not work, we will have to try and pry out the details of that transmitter from the engineers who maintain the tower.

What country are you in. Since you gave the distance in meters I suspect you are not in the US. Also is this tower a small roof top one, or a tall mast.

Unfortunately there are no hard and fast rules about placement. However 20 yards is considered acceptable for roof top, and 400 yards, roughly a 1/4 mile for towers from residencies.

Unfortunately if you equipment is affected making a tuned rejecter I think would be impossible.

There are a variety of radio frequencies covering 5G.

This is what I found out.

The frequency bands for 5G networks come in two sets. Frequency range 1 (FR1) is from 450 MHz to 6 GHz, which includes the LTE frequency range. Frequency range 2 (FR2) is from 24.25 GHz to 52.6 GHz. The sub-6 GHz range is the name for FR1 and the mmWave spectrum is the name for FR2.

But worse these towers more frequently than not transmit at a wide variety of frequencies for other customers.

So I think the most you can do is place the RF inductors I recommended in the +ve speaker leads. If that does not do the trick then I fear moving away from the tower is your only option.

RF interference with audio equipment is a bigger and bigger problem. I fear a big rise in your type of problem on this forum.

The real solution is that manufacturers are going to have to design their equipment with much better RF rejection. This needs to be written into law, with specified compliance requirements for RF rejection.

 

[avesatani]

So that nails it down. That is your problem. So try the inductor, if that does not work, we will have to try and pry out the details of that transmitter from the engineers who maintain the tower.

What country are you in. Since you gave the distance in meters I suspect you are not in the US. Also is this tower a small roof top one, or a tall mast.

Unfortunately there are no hard and fast rules about placement. However 20 yards is considered acceptable for roof top, and 400 yards, roughly a 1/4 mile for towers from residencies.

Unfortunately if you equipment is affected making a tuned rejecter I think would be impossible.

There are a variety of radio frequencies covering 5G.

This is what I found out.

The frequency bands for 5G networks come in two sets. Frequency range 1 (FR1) is from 450 MHz to 6 GHz, which includes the LTE frequency range. Frequency range 2 (FR2) is from 24.25 GHz to 52.6 GHz. The sub-6 GHz range is the name for FR1 and the mmWave spectrum is the name for FR2.

But worse these towers more frequently than not transmit at a wide variety of frequencies for other customers.

So I think the most you can do is place the RF inductors I recommended in the +ve speaker leads. If that does not do the trick then I fear moving away from the tower is your only option.

RF interference with audio equipment is a bigger and bigger problem. I fear a big rise in your type of problem on this forum.

The real solution is that manufacturers are going to have to design their equipment with much better RF rejection. This needs to be written into law, with specified compliance requirements for RF rejection.

I'm from Croatia.

The tower is roof top and as far as i know it's operated by T-com.
I've found the info provided by Croatian regulatory agency, that 700MHz, 3.5 GHz & 26 GHz will be used by 5G providers.

Well, moving away is not an option. Unless i suddenly become filthy rich

 

[TLS Guy]

I'm from Croatia.

The tower is roof top and as far as i know it's operated by T-com.
I've found the info provided by Croatian regulatory agency, that 700MHz, 3.5 GHz & 26 GHz will be used by 5G providers.

Well, moving away is not an option. Unless i suddenly become filthy rich

If it on the roof, no wonder that is causing you problems.

Other than the inductor, I can offer no further advice. Blocking three frequencies specifically at the same time I don't think is possible. At least I would have no idea how to go about it. It would be like tuning a radio to three stations at once. Radio and TV stations have a specific frequency, so you can use a targeted tuned rejection circuit. I have done that on a number of occasions. However if your problem is being picked up in the speaker leads, then using the inline inductor should drop your buzz 6db which may well be all you need in your situation. I can offer no further advice.

 

[avesatani]

Hello.

Just an update on the issue, the Yamaha was faulty in the end.
Bought Denon x1600h, hooked up everything, turned on and dead silence, no buzz just clear sound as it should be.