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  • Will a passive mixer do it?

    From Tobiah@21:1/5 to All on Sun Nov 21 13:17:06 2021
    I have a dual boot computer, and each OS must use a different
    audio interface (Can't get Linux to see my Studio 18/10).
    I'd like to just combine the stereo outs from each to go
    into the amplifier.

    I tried an old mechanical A/B switch from Radio Shack, but
    for some reason it picked up just enough noise to be unusable.
    It was also more annoying than you might think to reach over
    and flip the switch!

    So I was wondering how a passive mixer might work. I saw
    this online:

    INPUT 1 -------\/\/\/\---+
    ---+ R1 10K +------------ OUTPUT
    | | +----
    INPUT 2 -------\/\/\/\---+ |
    ---+ R2 10K |
    | (shields) |
    +---------------------+

    Will that do it? I have plenty of volume to spare, but
    I was curious about how much attenuation I'd experience.
    Is there a product that essentially does the same thing?
    I don't even really need volume controls.


    Thanks

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From John Williamson@21:1/5 to Tobiah on Sun Nov 21 22:03:34 2021
    On 21/11/2021 21:25, Tobiah wrote:

    Also, I noticed that on the back of my Denon power amp, each channel has
    two
    RCS inputs, one labeled 'CD', and the other 'Normal'. I assume that it
    would
    be a bad idea to try to utilize both at the same time, but I'm not
    completely
    sure.
    Check the circuit. The CD input will probably be designed to accept the
    usual digital 1 Volt input, while the normal *should* be 0.775 V at 600
    ohm impedance (0dB Reference voltage for pro gear), but for domestic
    gear, this will be a lower voltage.

    This could be either active or passive attenuation. Either way, you
    won't do any physical damage

    --
    Tciao for Now!

    John.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From John Williamson@21:1/5 to Tobiah on Sun Nov 21 22:06:38 2021
    On 21/11/2021 21:17, Tobiah wrote:
    I have a dual boot computer, and each OS must use a different
    audio interface (Can't get Linux to see my Studio 18/10).
    I'd like to just combine the stereo outs from each to go
    into the amplifier.

    I tried an old mechanical A/B switch from Radio Shack, but
    for some reason it picked up just enough noise to be unusable.
    It was also more annoying than you might think to reach over
    and flip the switch!

    So I was wondering how a passive mixer might work. I saw
    this online:

    INPUT 1 -------\/\/\/\---+
    ---+ R1 10K +------------ OUTPUT
    | | +----
    INPUT 2 -------\/\/\/\---+ |
    ---+ R2 10K |
    | (shields) |
    +---------------------+

    Will that do it? I have plenty of volume to spare, but
    I was curious about how much attenuation I'd experience.
    Is there a product that essentially does the same thing?
    I don't even really need volume controls.


    The attenuation will depend on the load and source impedances.

    --
    Tciao for Now!

    John.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Tobiah@21:1/5 to All on Sun Nov 21 13:25:37 2021
    Also, I noticed that on the back of my Denon power amp, each channel has two RCS inputs, one labeled 'CD', and the other 'Normal'. I assume that it would be a bad idea to try to utilize both at the same time, but I'm not completely sure.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From pallison49@gmail.com@21:1/5 to John Williamson on Sun Nov 21 15:29:13 2021
    John Williamson wrote:
    ====================
    Check the circuit. The CD input will probably be designed to accept the
    usual digital 1 Volt input,

    ** CD & DVD players output up to 2V rms.

    while the normal *should* be 0.775 V at 600
    ohm impedance (0dB Reference voltage for pro gear), but for domestic
    gear, this will be a lower voltage.

    ** 250mV is about normal sensitivity for tuners and cassette players.


    ...... Phil

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Scott Dorsey@21:1/5 to toby@tobiah.org on Mon Nov 22 01:13:47 2021
    In article <sned0j$2c8$1@gioia.aioe.org>, Tobiah <toby@tobiah.org> wrote:
    I tried an old mechanical A/B switch from Radio Shack, but
    for some reason it picked up just enough noise to be unusable.
    It was also more annoying than you might think to reach over
    and flip the switch!

    This is likely because when you connected the two devices to the same
    ground, you created a ground loop.

    A passive mixer will create the same ground loop. So figure out your
    grounding first.
    --scott
    --
    "C'est un Nagra. C'est suisse, et tres, tres precis."

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ty Ford@21:1/5 to All on Mon Nov 22 06:39:37 2021
    Holy Crap! A thread that reads like the good old r.a.p. newsgroup!

    Yay!

    Regards,

    Ty Ford

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Markus Ermert@21:1/5 to Ty Ford on Tue Nov 23 07:27:05 2021
    Ty Ford <tyre3ef0rd@gmail.com> wrote:
    Holy Crap! A thread that reads like the good old r.a.p. newsgroup!

    Yay!

    Usenet is alive.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)