244 buzz, hum, whatever

[Robert Andersson]

I got a problem with my 244. I have done my homework and searched everywhere byt I cant find out why This buzz or hum is filling my recordings.

You can hear it on the begining during this test recording.

Its recorded with sm58 and straight instrument into the 244 and audio is from headphone out into homestereo and filmed with iPhone. The noise is present in hedphones also.

Is it time to demagnitize och deflux whatever its called?

Im greatful for your thoughts and tips!
Sorry for the bad spelling

 

[SkywaveTDR]

I did not hear and hum and so it might be better to give us the problem than some long music.

 

[Robert Andersson]

Ok Skywave. I Will do it just for you. The hum is most present in the betingning of the clip, dont listen to the whole thing.

 

[Robert Andersson]

Forget about the clip.. is it possible that hum is being recorded when its time to demagnitise? Everywhere i have been reading it mentions high end loss as a sign that its time to demagnitise.

 

[-mjk-]

What happens when you record a track with no audio on the input? Do you hear the hum on playback?

 

[SkywaveTDR]

Hum can be due to the way a XLR cable is converted to unbalanced as in the 1/4 inch type input. These are not new units and there could be a dirty switch but I suspect that it might be a conversion. Mics source signal is from a transformer this is often across pins 2, 3 of the XLR and the ground is pin 1. If a signal is taken from a pair of wires such as 2 and 1 there will be an open coil situation and the signal will not be clean. Does it do it on more than one input channel on the unit? Is it there when using line inputs? I am trying to separate the sections so we know where to look next.

If it is a buzz do you have any Triac (dimmer) lamps around that produce these sharp edge spikes that can get into audio sections.