[Iain Churches]

"John Byrns" wrote in message
...
In article ,
Patrick Turner wrote:


The specs indicate 1.5mV of hum.

In horn speakers with 100dB/W/M that 1.5mV would plainly be audible
if the horns were that sensitive at 100Hz, and the hum was 100Hz hum.

Has any attempt been made to reduce the hum?

Patrick Turner.

I agree, 1.5 mV of hum is way too much and easily audible even on
speakers of moderate efficiency. I shoot for a hum level 80 dB below 1
Watt without feedback, which translates to about 0.3 mV into 8 Ohms.


Regards,

John Byrns


My 50W amp measured wideband has 300µV of noise including hum
I did not "shoot at it" I was lucky, it just came out that way:-))

Thanks John, the info which you and Patrick have provided in this
thread is of great interest.

Regards to all
Iain