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geoff geoff is offline
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Default Where does the hum come from?

On 12/02/2021 10:15 am, geoff wrote:
On 12/02/2021 2:02 am, Scott Dorsey wrote:
geoffÂ* wrote:

Look at the picture in the OP link. RCA unbal outputs.


I have no graphics here.Â* So RCA on one end, what is on the other end?


No graphics ?Â* This *is* the 21st Century ! Or are you working on one of
these ?Â* ;- )

https://www.facebook.com/photo/?fbid...57424488371333


(for the insecure the link is to a picture on Facebook of a computer).


If the RCA connector is run to pins 2 and 3 of an XLR on the other end
with pin 1 lifted (as is a common and reasonable configuration), then
the case of the powered speaker won't be connected to the case of the
DAC until power is applied.Â* So in that case the thing would hum in the
configuration the original poster describes.

But without knowing what the cable is, you don't know for sure.
--scott

Well can be sure it isn't a twin untwisted heavy-gauge speaker cable !

The LSR305 has bal (and equally unbal) jack and XLR inputs. At least
mine have, and no hum even when connected via several intermediate
devices to a PC, a mixture of bal and unbal.

Would help to know the 'quality' and make-up/configuration of the
RCA-to-whatever cable.

geoff


'Slight' correction, mine are LSR705P.

geoff