Need to clean up power...

[moriendi]

Hi guys,

I'm in situation that my studio monitors pop when aircon turns on or off, spikes I guess, and there is some high frequency noise. How to clean that mess up? Apart from bringing in 5 meters of power cable through middle of the room to connect them to the other power source which is not elegant.

How good is this thing in cleaning power:
Line-R 1200VA Automatic Voltage Regulator

I can get it cheap, it would be nice if it works since I can connect then my monitors and pc on it, or maybe you can suggest me something else? Since my monitors are active, there is some space inside their amp section for some small diy work.

Thanks for the answers.

[bob91343]

Before you start it is prudent to figure out where the noise is entering your system. You have made an assumption that it's coming in via the power line. I'm not so sure.

There is a whole engineering discipline devoted to such things. Don't jump and spend money until you are sure. Of course if you can borrow the unit and see, that would be good.

I am not a big fan of APC anyway. Not because of their stuff but because their advertising has annoyed me from the beginning. Also, the unit you are looking at is a voltage regulator, something you don't need. You need spike suppression, but where is your gear seeing the spikes?

[Enzo]

I agree with Bob, find out what the problem is before you try to solve it.

It may not be elegant to run cables 15 meters, but just for troubleshooting, get a power cord and do exactly that. Does connecting the unit to a different mains circuit prevent the noise? If it does, then perhaps mains filtering will work, but if it makes no difference, then your noise is raqdiated or coming in some other way.

Your monitors are driven by an amp, and the signal to the amp is possible coming through some processing such as a graphic EQ, and the signal to that came from a mixer or some other source. So disconnect the input cables to the monitor speaker amplifier. Still pop? Does the volume control on the amp affect the pop?

And if the amp still pops with the volume down, it almost HAS to be coming through the mains. But if the volume control stops the pop, then move back up the signal path and check at each step to find what is sensitive.

[moriendi]

Sorry if I didn't made it clear, I have actually tried connecting speakers to the outlet on the other side of the room and then were no pops and noise at all. Even the fridge is connected to that line where is aircon and my setup, however, due to layout of the room I cannot afford to have 5m of cable across the room, I need to fix that situation.

I've put link to APC device because I saw it has RFI/EMI supression, what about spikes? Or something else somebody can suggest? Small DIY kit on ebay?

Thanks.

EDIT: Maybe this? http://www.belkin.com/PureAV.process?Section_Id=202496

[firechief]

[QUOTE=moriendi;2207400]Sorry if I didn't made it clear, I have actually tried connecting to the outlet on the other side of the room and then were no pops and noise at all.
Please clairify- you plugged the AC into a different circut, and the problem went away? Is this a 110V AC? sounds like you need to get power from someplace else. Yes?

[moriendi]

Please clairify- you plugged the AC into a different circut, and the problem went away? Is this a 110V AC? sounds like you need to get power from someplace else. Yes?

It's a 230V AC, Europe. Sorry, but English is not my main language, I've fixed post now. I believe there are no doubts now.

[bob91343]

A surge protector is NOT what you need. They merely protect a load. Your load isn't failing; it's just susceptible.

You need a spike suppressor. Don't try to fix this with someone's generic power solution; you need to find out just what's happening to your system and address that.

You might solve it as simply as adding a ferrite core on a power cord. Or some judicious bypassing inside one of the units. It's not easy to tell from here. Still, it could be radiated noise, which requires shielding to correct.

There could also be something wrong in the air conditioning power circuit. There is no easy solution; if you find one, it's pure luck. Relying on luck gets expensive.

[Spiny]

Look at the source of the noise, The AirCon switches in and out with some form of controlled switch (bi-metallic, relay etc). It probably once had a suppressor (cap) across the contacts which is now useless.
Replace or put suppressors across switch contacts. If you do not know what to use ask an electrician- this is 230V and must use correctly specified parts

[ChrisA]

Originally Posted by moriendi

Hi guys,

I'm in situation that my studio monitors pop when aircon turns on or off, spikes I guess, and there is some high frequency noise. How to clean that mess up? .

The best solution is always to put the noise suppressor at the source. What you need is a noise filter. These are boxes with inductors and caps inside. They look like an over size outlet strip

You may want one one both the A/C unit and the audio gear.

I must own a dozen of these "isobar" filters. I've taken a few apart to look inside and they are just LC filters with MOV surge suppressors inside a sturdy aluminum box.
Tripp Lite ISOBAR Surge Protection - 4 Outlet AC Line Filter

Likely if you put one of these on the AC and one on the audio gear you will be fine. if not you need a much stronger filer on the audio gear. Like this
Furman PL-8C | Sweetwater.com

The simplest thing is to replace the standard IEC power input jack with a filtered jack. They cost only $2 to $5 and take up zero space.. I always use these in everything I build. It's not extra work as you need a IEC input anyway.
EAS, EBS Series