adamdea
You are not a sound quality evaluation device
Ok I was delighted with my new Atc scm 40s which were installed while I was away last week.
They have power and signal running together through a conduit, which I was a bit concerned about. This does not so far seem to be a problem, although I haven't had the chance to run a test yet.
They are hard up against a wall but this doesn't seem too much of a problem. In fact they sound pretty great to me. I have put in a bit of correction from the antimode which I think might be slightly over correcting the bass- I will have to fiddle a bit further.
So far so good. At night I noticed though that there was a funny noise coming out of one tweeter (if I put my ear fairly close). I couldn't hear this during the day. Probably the ambient noise level masking it, I mused. Could it be picking up from mains to signal cable on that side? Err no it seems because the noise is the same when I pull out the xlr in the back of the speaker.
Now the installer has used very audiophile looking screened mains cables with a fancy iec socket. The power come out of one socket in the wall, coming out to a sort of block with two cables coming out and into a conduit on either side to the speakers. I did wonder whether the super duper screened cable might be the problem, if for some reason it was working as an antenna.
Then after random fiddling, poking about and gentle swearing I somehow established that the funny noise from the tweeter comes out when I turn the lights on. Or rather one lighting circuit on. This circuit operates lights around the room, but most obviously an uplighter which is about three feet above the ATC in question. There is a similar uplighter above the other speaker (on the same circuit), but that speaker doesn't make any noise when the light is on. The lighting circuit is on a dimmer switch, but turning the dimmer doesn't seem to affect the noise. The switch is, however, very near to the one which does make the noise.
Any suggestions as to cause or solution? I suppose I could try taking the light bulb out, powering the speaker from another socket using an extension lead (experimentally only- I would be skinned alive if I tried it permanently), and possibly try moving the speaker further out into the room (ditto).
They have power and signal running together through a conduit, which I was a bit concerned about. This does not so far seem to be a problem, although I haven't had the chance to run a test yet.
They are hard up against a wall but this doesn't seem too much of a problem. In fact they sound pretty great to me. I have put in a bit of correction from the antimode which I think might be slightly over correcting the bass- I will have to fiddle a bit further.
So far so good. At night I noticed though that there was a funny noise coming out of one tweeter (if I put my ear fairly close). I couldn't hear this during the day. Probably the ambient noise level masking it, I mused. Could it be picking up from mains to signal cable on that side? Err no it seems because the noise is the same when I pull out the xlr in the back of the speaker.
Now the installer has used very audiophile looking screened mains cables with a fancy iec socket. The power come out of one socket in the wall, coming out to a sort of block with two cables coming out and into a conduit on either side to the speakers. I did wonder whether the super duper screened cable might be the problem, if for some reason it was working as an antenna.
Then after random fiddling, poking about and gentle swearing I somehow established that the funny noise from the tweeter comes out when I turn the lights on. Or rather one lighting circuit on. This circuit operates lights around the room, but most obviously an uplighter which is about three feet above the ATC in question. There is a similar uplighter above the other speaker (on the same circuit), but that speaker doesn't make any noise when the light is on. The lighting circuit is on a dimmer switch, but turning the dimmer doesn't seem to affect the noise. The switch is, however, very near to the one which does make the noise.
Any suggestions as to cause or solution? I suppose I could try taking the light bulb out, powering the speaker from another socket using an extension lead (experimentally only- I would be skinned alive if I tried it permanently), and possibly try moving the speaker further out into the room (ditto).