Ticking Amplifier!!!

[admin_exported]

Hi All,

Introductions first............

I'm brand new here as I begin investing in HIFi equipment. I'm starting small as I want to gather some quality information and knowledge before I invest in high end gear. I decided to kit out a small living room with HiFi seperates and I have started with the budget Cambridge Audio Topaz AM1 paired with the JBL Control1 speakers. I'm using my Sony NWZ-X1060 Walkman as a source via the Lineout. It sounds great to my ears as it is a major step up from the minisystem I used to listen too.

However, I have a potential issue with the amplifier as there is an unusual ticking sound coming from the inside of the unit. This appears to be close to the power button and the ticking is loudest when the power switch is set to off position. It is constant at about once per second.This doesn't appear to be affecting the operation of the amp as it's sounds great and is not overheating.

Cambridge Audio support says to contact my supplier ( Richersounds) and I am awaiting a response from them. In the meantime I am curious as to whether this is normal or otherwise for an integrated amplifier.

 

[Sizzers]

In the meantime I am curious as to whether this is normal or otherwise for an integrated amplifier.

No.

Further than that I can be of no further help, I'm afraid, but others might.

Edit: Faulty relay springs to mind.

 

[Dougal1331]

Yes, probably a dodgy relay.

Maybe a 'leaky' capacitor in the power supply stage trickling a small amount of current and tripping the relay.

Could be talking bollards here, but I'd recommend a return to the retailer. There may be no other ill-effects yet, but that could all change...

 

[Anonymous]

Thanks guys. The more I hear this thing ticking away in the room the more I am convinced I need to return it. i have unplugged it from the mains now.

Pity it was by telephone order. Now for the messy bit of repackaging for return. I think I might upgrade to the AM5 while I'm at it.

 

[Anonymous]

Problem Solved?????

A replacement amplifier gave the exact same syptoms as mentioned in original post so decided to investigate the issue as this was too much of a coincidence. I should mention I have made this query on other forums as the whole thing has been driving me nuts for the past week.

Last night I turned my PC speakers up really loud to see if I could pick up anything like electrical ticking , sure enough it was there. Then I immediately thought of an electric fence plugged into our mains in a garage at the end of our yard. Today I went and disconnected the fence and there you have it, ticking from my amps circuit board stopped.

I am amazed by this. But, what is the cause? Why does it make the circuit board on my amp tick and on no other device in the house, not even TV speakers etc.? and is this damaging my equipment? Should I still swap out this amp?

I presume some sort of interference is coming back the power circuitry but is this contaminating my power supply that could lead to component damage and failure?

Thank you for taking an interest in this issue and I would really appreciate your feedback.

 

[Anonymous]

Is this something mains conditioning could solve?

 

[floyd droid]

Then I immediately thought of an electric fence plugged into our mains in a garage at the end of our yard.

Flippin eck, bit rough up your way isnt it !.

 

[drummerman]

Then I immediately thought of an electric fence plugged into our mains in a garage at the end of our yard.

Flippin eck, bit rough up your way isnt it !.

regards

 

[Mooly]

Unusual problem...

I suspect that you hearing the mains transformer in the amp "respond" to a sudden small change in mains voltage caused by the fence circuit or perhaps "harmonics" on the mains as this thing operates. Another route that would require investigation (its a bit unlikely though) would be if there was electrical leakage to ground from the fence and that somehow caused a slight ground voltage (and hence current) to develop... I can't really see that though. If that were so then the amp would be silent if you had just the amp and speaker and nothing else connected to it (and dare I say it no mains ground to the amp either for the purposes of the test only... safety implication apply of course).

Is the electric fence thingy an old type with a mechanical type contactor to "pulse" the fence with a high voltage (like an old car ignition system with points and coil) or is it more modern and all electronic.

Is it harmful... probably not because any voltage spikes won't make there way onto the equipments power supplies (talking normal transformer type supplies) although for equipment with switch mode type power supplies (TV/DVD/PC etc) I would want to see exactly what the problem and magnitude was. Probably OK though in the big scheme of things.

 

[Anonymous]

@Mooly, thanks for that input. The fence energizer is about 7 or 8 yrs old, apart form that I cannot comment on the technology in the unit. It is a neccessary piece of equipment here though as there are a lot of cattle in the area and I use it as back up against local farmers fences breaking or being badly maintained. We have had a couple of very damaging "break-ins" in the past.

I am going to invest in a new modern unit to see if it improves things. Given that there is no "audible" feedback on all of my other electronics I could simply trade for a different amp and take my chances that would fix the "symptoms" but it would not fix the problem. In a weird twist this whole issue has raised my awareness of a potential problem with this fence energizer.

I'm still perplexed as to how this amp is the ONLY device in the house that is responding in this way. Is there a scientific explanation for this, you mention harmonics???????

 

[Mooly]

A scientific explanation

Trying to put this simply, the mains transformer in the amplifier is quite a hefty component consisting of an iron/ferrite core and many turns of wire around it. Now the mains supply should be a near perfect sine wave and when it is the transformer is relatively inaudible. The problem occurs when the mains supply deviates from this sine wave. If the waveform isn't pure then the windings of the transformer can become very audible... the windings acting a bit like a speaker coil. Larger transformers show this effect more than small. Sometimes transformers just seem to buzz (sometimes worse at certain times of day) and this again is caused by non sinusoidal mains supplies. A lot of electronic equipment doesn't draw current in a linear fashion from the mains and this can result in a "flattening" of the tops and bottoms of the sine wave and even worse sometimes just distortion on either the top or bottom part of the sine. That problem causes a slight DC shift in the mains voltage (yes the mains can have a "DC" shift on it) of a few hundred millivolts or more and is the most common reason for "buzzing" power transformers as it causes the magnetic core to "saturate".

If your fence is causing a momentary "dip" in the mains each time it pulses the fence then this is made audible by the transformer windings. This can be though of as harmonic distortion in just the same way that an audio amplifier can generate harmonic distortion.

If you have ever heard a pure sinusoidal (such as 50 or 60 hz) tone via an amp and speaker you'll understand the meaning "pure". Now imagine that drawn out as the sine wave it is. If you were to add the tiniest glitch on each cycle (no bigger then the width of ink used to draw the sinewave) then the character of the tone would alter immediately to become much harsher in nature. That is the effect of the "harmonics".

In the first post you mention it does it when switched off. That will probably be because the mains transformer is still powered up. Why ? Because to switch the "other" or low voltage output side is cheaper and easier and doesn't require the use of safethy specified components.

 

[drummerman]

More non-scientific, I have found that 'adjustable' appliances such as dimmer switches or crock-pots can be the worst offenders.

Something as simple and cheap as a Tacima mains block may provide some isolation depending on how severe the problem is.

regards