Electronics question

Post by r***@optonline.net
Not an HDTV question but I know there's a lot of knowledge here.
My desktop computer has a Creative Labs sound card with a pair of Bose Companion
2 speakers connected to it. They work fine, but when I have no sound coming out
of them, if I turn the volume control on the speaker itself all the way up, I
can hear a faint hum. Is this indication of a problem? Grounding? There's no
separate grounding lug, just the cables between the two speakers and the cable
to the computer. Any idea what could be causing this? Thanks.

Incomplete filtering of the DC power.

But if you were to compare the hum level to the signal level, you'd find
the hum to be tiny. Note that you have to turn the volume all the way up
to hear the hum. If there were a signal there, it would be loud, as in
LOUD.

It's normal.

--
Gene E. Bloch (Stumbling Bloch)

r***@optonline.net

2013-09-13 22:17:19 UTC

Incomplete filtering of the DC power.
But if you were to compare the hum level to the signal level, you'd find
the hum to be tiny. Note that you have to turn the volume all the way up
to hear the hum. If there were a signal there, it would be loud, as in
LOUD.
It's normal.

Okay, thanks. So I don't have to worry about a bad connection or anything?

Gene E. Bloch

2013-09-13 22:31:34 UTC

Incomplete filtering of the DC power.
But if you were to compare the hum level to the signal level, you'd find
the hum to be tiny. Note that you have to turn the volume all the way up
to hear the hum. If there were a signal there, it would be loud, as in
LOUD.
It's normal.

Okay, thanks. So I don't have to worry about a bad connection or anything?

You can worry if you like. Far be it from me to deny you that pleasure.

--
Gene E. Bloch (Stumbling Bloch)

r***@optonline.net

2013-09-14 02:38:29 UTC

Incomplete filtering of the DC power.
But if you were to compare the hum level to the signal level, you'd find
the hum to be tiny. Note that you have to turn the volume all the way up
to hear the hum. If there were a signal there, it would be loud, as in
LOUD.
It's normal.

Okay, thanks. So I don't have to worry about a bad connection or anything?

You can worry if you like. Far be it from me to deny you that pleasure.

Got me. What I meant was that the hum isn't the result of any kind of bad
connection?

Gene E. Bloch

2013-09-14 22:25:20 UTC

Incomplete filtering of the DC power.
But if you were to compare the hum level to the signal level, you'd find
the hum to be tiny. Note that you have to turn the volume all the way up
to hear the hum. If there were a signal there, it would be loud, as in
LOUD.
It's normal.

Okay, thanks. So I don't have to worry about a bad connection or anything?

You can worry if you like. Far be it from me to deny you that pleasure.

Got me. What I meant was that the hum isn't the result of any kind of bad
connection?

Oh. Well, since I already said that, I thought I didn't need to repeat
it.

From my initial reply,
"Incomplete filtering of the DC power."

That is an internal "feature" of the speakers, and of just about every
other audio device.

--
Gene E. Bloch (Stumbling Bloch)

r***@optonline.net

2013-09-14 23:45:47 UTC

Incomplete filtering of the DC power.
But if you were to compare the hum level to the signal level, you'd find
the hum to be tiny. Note that you have to turn the volume all the way up
to hear the hum. If there were a signal there, it would be loud, as in
LOUD.
It's normal.

Okay, thanks. So I don't have to worry about a bad connection or anything?

You can worry if you like. Far be it from me to deny you that pleasure.

Got me. What I meant was that the hum isn't the result of any kind of bad
connection?

Oh. Well, since I already said that, I thought I didn't need to repeat
it.
From my initial reply,
"Incomplete filtering of the DC power."
That is an internal "feature" of the speakers, and of just about every
other audio device.

Okay, thanks.

Gene E. Bloch

2013-09-15 23:11:00 UTC

Incomplete filtering of the DC power.
But if you were to compare the hum level to the signal level, you'd find
the hum to be tiny. Note that you have to turn the volume all the way up
to hear the hum. If there were a signal there, it would be loud, as in
LOUD.
It's normal.

Okay, thanks. So I don't have to worry about a bad connection or anything?

You can worry if you like. Far be it from me to deny you that pleasure.

Got me. What I meant was that the hum isn't the result of any kind of bad
connection?

Oh. Well, since I already said that, I thought I didn't need to repeat
it.
From my initial reply,
"Incomplete filtering of the DC power."
That is an internal "feature" of the speakers, and of just about every
other audio device.

Okay, thanks.

Another thing to RE-emphasize is that if you have to turn the audio
device so far up to hear the hum, it constitutes only a tiny fraction of
the signal and is harmless.

That's what I meant to imply when I said "Note that you have to turn the
volume all the way up to hear the hum. If there were a signal there, it
would be loud, as in LOUD." That is, it would break your eardrums, your
speakers, and your windows. Probably not your Windows, though.

Another cause for the hum that I didn't mention is just stray fields
from the ubiquitous AC in your house. Again, it's both trivial and
unavoidable - and not anything worth worrying about, unless worrying is
a hobby for you (it is for me, but only in other areas of life!).

--
Gene E. Bloch (Stumbling Bloch)

G-squared

2013-10-23 03:15:54 UTC

Universal rule. When you look for noise, you WILL find it whether it be audio, video or anything else for that matter. The important question, does it interfere with the enjoyment of using the gear?

FWIW I gave Bose Companion 2 series II speakers on this PC and the noise is barely detectable. Audio out is from a Gigabyte 780 series AMD board.

G²

G-squared

2013-10-23 03:18:10 UTC