2. amps-preamps
  3. 174684-115845

Strange ticking noise when amps were powered on from cold

Any one encountered this phenomenon? I have a pair of Aesthetix Atlas Monos. When they were powered on from cold I could hear some continuous ticking noise (10-15 beat per second) if I stick my ear right next to the speakers. VERY faint. The noise was gone in about 5 mins once the monos were warmed up. As long as the monos’s main switches were on the noise would not return regardless the monos were playing or stand by. It only happened when they were turned on from cold (e.g. after a power failure in the neighbourhood ). searched online and some people suggest that it is the capacitors charging?

 

Steps I’ve done to diagnose the problem:

1. Turn off preamp-same problem

3. Replace 6SN7 tubes

3. use other amps-no noise

4. plug them in other main sockets-same problem

5. switch off all other appliances at home (fridges, dishwasher, modem, router, down lights)-same problem

6. Disconnect all rechargeable devices (laptops, robot vacuum cleaner, power bank, electric toothbrush)-seemed to quiet the noise a bit but not to sure as it was very faint in the first place

At the moment it’s not very practical for me to take the monos to other places to try.

Your input is much appreciated. 
 

 

steven365
steven365 OP
26 posts
 

@tomstruck 

Thanks mate. One of the potential buyers acutally contacted Aesthetix regarding this and was advised that they never heard of such probem before. 

I should add that I might not have the best AC in our house. Previously whenever my wife switched on the dimmable down lights I could hear a pop from the speakers. A Torus isolation transformer fixed it. However, now even with the down lights switch off I could still hear the ticking noise in the first 5 mins.

steven365 OP
26 posts
 

@oldhvymec 

You may be right that the monos are just fine but I just feel a bit hesitant selling them if there is slightest chance that they are faulty. Just trying to be a responsible and ethical seller. But how could the noise appear and disappear on both units simutaneously? What's the chance of them becaming faulty at the same time? This is really beyond me...

steven365 OP
26 posts
 

@tomstruck 

Are yours the stereo version or the monos? You sure you couldn’t hear the same ticking noise? As I said it’s VERY faint and one really has to stick the ears to the drivers to hear it. I didn’t notice it before either. Could you please switch off the mains on tour Atlas, wait for at least one hour,  power then back on from cold then listen to the speakers closely?

oldhvymec
5,101 posts
 

Have you checked the voltage with just an old analog volt meter? Maybe it's something in your house that's causing the noise. Something weird. Can you move them to a different system or speakers or location? 

The source? The preamp? Both at the same time is before the amps. At the exact same time they switch. Look before the amps..

Just thinking out loud...

steven365 OP
26 posts
 

@oldhvymec 

I don’t have a volt meter. The voltage on my UPS screen shows the correct local voltage of 230v

Not very practical for me to move them to a different system. No audiophile friend living close by…

Tried with the preamp and DAC disconnected. Same symptom.

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