Mechanical Hum from Class A Amplifier Clayton


Hi All,

Need some advise,

I have a paid of Clayton M300 Monos,

Speakers Tested on were Danley SH50 Horn 100db and Legacy Audio Whisper XD 94db

I noticed one of the mono block has a louder Mechanical Hum and tends to get hotter. The amps are giving off a Hiss sound with some mechanical buzz noise in the midrange drivers.

The other mono block has hiss and slight hum with a much lower Mechnical buzz from the amplifier. What concerns me is the Hiss noise. Its not only a hiss but some buzz mixed into it.

I tried connecting the amps directly to the wall socket and to a AC Regenerator and nothing seems to sort the issue out. Is this normal noise for a Class A amplifier to make a loud hissing noise? My Tube amps have a lower noise floor specially the Bob Carver which are dead silent, The ATI amplifier is Also Dead Silent.
dragon_vibe

Showing 1 response by georgehifi

If the Class A bias is higher on one amp it will be hotter, and if it is bias higher than the specs then it will stress the transformer and cause it to hum.
It needs to be looked at, do not play it. I have seen a transformer damaged because the bias was too high.

Cheers George