Constant fizzing/sizzling from tweeters

[InductionRoar]

I have had my current set up (Naim CD5X, NAC 112X, Flatcap 2x, NAC 150X and B&W 805S) for over 10 years now (all new).

After a short while I could hear a very feint interference noise from the speakers and have tried to address this with speaker cables (I have used Van Del Hul, Naim and am currently on Chord) all to no avail but as it was so small I gave up as other people said it was nothing to worry about.

Unfortunately, the interference is getting worse and has got to the point that it is really spoiling the experience of listening through my speakers and I have been using my headphones lately. The interference remains constant regardless of volume and only comes from the tweeters. The system has never been played overly loud (it's a fairly small room) but I am a complete novice and have no idea where to start looking for the problem.

Any suggestions would be appreciated.

[M3Gar]

Unplug everything one by one.
If it is still doing it when the only thing left plugged in is the amp then that will be your problem.
Sounds like a bad earth.

[InductionRoar]

M3Gar said:

Unplug everything one by one.
If it is still doing it when the only thing left plugged in is the amp then that will be your problem.
Sounds like a bad earth.

Thanks for the reply.

I've just had a play.

The CD player, pre-amp and power supply is always switched on and I only switch the power amp on whenever I want to listen.

I have just switched the power supply off (this powers the pre-amp which has no dedicated power lead) and switched it back on again.

Naim pre-amps automatically start up on mute for a minute whilst the amp warms up. Whilst the amp was on mute the fizzing was hardly audible (how it was when I first noticed it 10 years ago) but as soon as the mute self cancelled it made a sort of bang noise and continued to fizz loudly. Pressing the mute button manually thereafter made no difference to the fizzing at all.

Does this help?

[jet_noise]

You say you listen on headphones and it's OK. Into where do you plug your headphones?
Can you borrow another preamp and/or amp?
Can the preamp be unplugged from the amp, and if so is the fizz still there?
If the CD player is unplugged (from the preamp) is the fizz still there?

You say it has got worse over time.
It sounds (pun intended) to me as if a component (a resistor I would expect) in the preamp has become noisy and is steadily worsening. This rather than interference being picked up (although that's still a possibility),

regards,
Jet

[InductionRoar]

jet_noise said:

You say you listen on headphones and it's OK. Into where do you plug your headphones?
Can you borrow another preamp and/or amp?
Can the preamp be unplugged from the amp, and if so is the fizz still there?
If the CD player is unplugged (from the preamp) is the fizz still there?

You say it has got worse over time.
It sounds (pun intended) to me as if a component (a resistor I would expect) in the preamp has become noisy and is steadily worsening. This rather than interference being picked up (although that's still a possibility),

regards,
Jet

Thanks for your help.

I have a separate headphone amp so I think that the CD player can be eliminated.

The service manager from my local Naim hi-fi specialist came round yesterday to test my gear and he concluded that there is no fault and that "they all do that sir" which was in one way reassuring but in another disappointing. He could feel a different pressure coming from the tweeters more than he could actually hear the fizzing and he was quite surprised I could hear anything.

He did bring with him a brand new Naim Nait 5 which we set up from just the CD player (bypassing the outboard power supply) and that made an identical noise (maybe 7/10 in volume if you say mine is 10/10) but I found the hum of the actual amp to overpower the fizzing from the tweeter so this gives an idea as to the volumes in question. I think it is a case of my hearing being a little bit too critical and he was confident that it wasn't picking up interference.

He concluded that it really wasn't worth the cost of servicing the parts (which I think was very honest given he would in his financial interest to do so) because they could come back exactly the same due to the fact he couldn't diagnose a fault.

I think it has become more noticeable to me of late because I have been using more audiophile recordings with profound areas of silence (acoustic guitar, piano etc) but I shall definitely monitor it and if it worsens further I will have to commit to sending off to Naim which I am very keen to avoid for a multitude of reasons. I also think the pre-amp is the source but if the item is not faulty, as he was pretty confident it isn't, I am thinking that if it ain't broke don't fix it and I'll put the money aside for when it does.

Thanks again.

[PBDirector]

InductionRoar said:

He could feel a different pressure coming from the tweeters more than he could actually hear the fizzing and he was quite surprised I could hear anything.

Would mind clarifying what you mean by "feel"? Do you mean feel as in air movement?

I'm really struggling with the idea of a fizzing so marked that it creates a SPL that can be felt but that can't be heard by a repair engineer that's presumably competant.

[InductionRoar]

PBDirector said:

InductionRoar said:

He could feel a different pressure coming from the tweeters more than he could actually hear the fizzing and he was quite surprised I could hear anything.

Would mind clarifying what you mean by "feel"? Do you mean feel as in air movement?

I'm really struggling with the idea of a fizzing so marked that it creates a SPL that can be felt but that can't be heard by a repair engineer that's presumably competant.

I assume so. I didn't ask for clarity but he said he could barely hear the fizzing but could feel the pressure more than anything but even then so minimal as to be of concern. This was with his ear right next to the tweeter.

[jet_noise]

InductionRoar said:

PBDirector said:

InductionRoar said:

He could feel a different pressure coming from the tweeters more than he could actually hear the fizzing and he was quite surprised I could hear anything.

Would mind clarifying what you mean by "feel"? Do you mean feel as in air movement?

I'm really struggling with the idea of a fizzing so marked that it creates a SPL that can be felt but that can't be heard by a repair engineer that's presumably competant.

I assume so. I didn't ask for clarity but he said he could barely hear the fizzing but could feel the pressure more than anything but even then so minimal as to be of concern. This was with his ear right next to the tweeter.

Having your own home hifi service visit - very PH Private Although I appreciate the kit is fairly high end!
Maybe you do just have supersensitive hearing. Like some have extra tastebuds or can see a gnat at a thousand paces? Do you use your ears more than the average person, a musician maybe who is used to analysing what they hear in some detail?
My hearing is pretty knackered these days. Never been wonderful but made up for it by being able to listen rather than just hear.

Teaching my grandmother etc but all amps do hiss. Which is what the service chap is saying I think. Although PBDs observation is also relevant,

regards,
Jet

[PBDirector]

You may well be blessed with hearing that can detect it, and to live in an environment that gives you the opportunity. I recommend you acquire a toddler who will soon mask the fix for you.

I have to say, if it were me, I'd employ a friend to carry out a best of five blind test to see whether the systems actually on to rule out my own fading faculties/ brain.

[conkerman]

Can you borrow a (non NAIM) amplifier from somewhere?

Have you tried going back to the NAIM speaker cable, I seem to remember from the dark and distant past that they were fussy to capacitive load.

[InductionRoar]

conkerman said:

Can you borrow a (non NAIM) amplifier from somewhere?

Have you tried going back to the NAIM speaker cable, I seem to remember from the dark and distant past that they were fussy to capacitive load.

Thanks for the replies chaps.

I could borrow a non-Naim amp but would need to connect it via RCA as opposed to their preferred DIN so it may not be so representative? I noticed no difference to the fizzing when I changed my Naim cable for Chord and when I phoned Naim he asked me what cable I was using and he said Chord was fine, although he didn't ask me which cable I used.

The chap who came around said he too prefers Chord to the Naim cable so I think until it worsens I will leave it alone.