Connecting powered speakers to a sound card

[Rod@Hillhead]

Hi,
I have just run cables around the house with the idea of sending audio
output to various powered speakers from the PC's sound card. This
works well with the shorter leads which use standard cables bought
with jack plugs fitted. The longer cables are made from high quality
twin speaker cable, with jack plugs fitted by me. The output from at
least one channel is faint and there is also a hum heard. My question
is whether this is most likely due to the fact that the speaker cables
are not screened, or is it more likely that I have a bad connection in
the jack plugs or other cable joints ( I have had to connect the jack
plugs to a short length of thinner wire as the speaker cable is too
thick)?
Many thanks for any guidance,
Rod

 

[John Popelish]

Rod@Hillhead wrote:

Hi,
I have just run cables around the house with the idea of sending audio
output to various powered speakers from the PC's sound card. This
works well with the shorter leads which use standard cables bought
with jack plugs fitted. The longer cables are made from high quality
twin speaker cable, with jack plugs fitted by me. The output from at
least one channel is faint and there is also a hum heard. My question
is whether this is most likely due to the fact that the speaker cables
are not screened, or is it more likely that I have a bad connection in
the jack plugs or other cable joints ( I have had to connect the jack
plugs to a short length of thinner wire as the speaker cable is too
thick)?

The line level signals travel this sort of distance through
almost any kind of wire, so I doubt the weak signal is
anything but a broken wire or bad connection at one end.
These are rather high impedance signals, so fatter wire does
little good, and increases the capacitive load across the
pair and to the surroundings.

However, such signals are only a volt r so, and will pick up
less competing hum when running near power lines in the
walls, if they run in shielded wire. A shielded twisted
pair (signal and ground in the pair) would work best, if the
shield is grounded only at the receiving end (shield and
ground conductor of the pair connected together at the
receiving end, shield unconnected at computer end).

--
Regards,

John Popelish

 

[JANA]

You should be using shielded audio interconnect wire for line level audio.
The shield at each end must go to the ground side of the source and
destination equipment being connected. The wire should be run where it is
not parallel to power wires.

--

JANA
_____


"Rod@Hillhead" <remcg@tesco.net> wrote in message
news:c7506e8b-dd19-40a7-811e-f0f8c08099a8@d21g2000prf.googlegroups.com...
Hi,
I have just run cables around the house with the idea of sending audio
output to various powered speakers from the PC's sound card. This
works well with the shorter leads which use standard cables bought
with jack plugs fitted. The longer cables are made from high quality
twin speaker cable, with jack plugs fitted by me. The output from at
least one channel is faint and there is also a hum heard. My question
is whether this is most likely due to the fact that the speaker cables
are not screened, or is it more likely that I have a bad connection in
the jack plugs or other cable joints ( I have had to connect the jack
plugs to a short length of thinner wire as the speaker cable is too
thick)?
Many thanks for any guidance,
Rod