Monitor out or Stereo out?

Discussion in '2488 and DP-24/32 Digital Portastudios' started by Saxomohawh, Jan 25, 2020.

  1. Saxomohawh

    Saxomohawh New Member

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    Hi, this question is for DP 24 SD. What gives the highest sound quality, "Monitor out" with TS cables, or "Stereo out" with RCA? I have been looking at the block diagram, but that doesnt really help in this case.
  2. Phil Tipping

    Phil Tipping Well-Known Member

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    The monitor output goes through an extra amp stage after the DAC so I guess the main stereo outputs are better quality, although I would guess the difference is very small - try a listening test to see if you can hear any difference. The monitor outputs have an advantage in that they are balanced (maybe that's all the extra stage provides?), so should drive longer cables or be more tolerant to interference.
    Update: the schematics seem to show both outputs pass through an amp, and they don't appear to be in series as implied by the block diagram, so maybe they are the same after all... or I've just misread the diagram! (see post #4 below)
    Last edited: Jan 26, 2020
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  3. Mark Richards

    Mark Richards Well-Known Member

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    My testing a while back showed the signal-to-noise ratio for the Monitor circuit confirmed the data on the owner manual Specification page; and the Spec page shows the Stereo Out to have the same specs.

    The quality of the connecting cable you use will have an impact. Cheap cables/connectors will affect the audio quality.
    Last edited: Jan 25, 2020
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  4. Phil Tipping

    Phil Tipping Well-Known Member

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    Thanks Mark. Had a closer look at the schematic... there's a DAC (AK4384) followed by a single op-amp (BA4580RF-E2) stage for both outputs. The resistors and capacitors around the op-amp stages are different, presumably for the different gains required, so you could maybe argue there's a smidge more noise on the higher-gain circuit (the monitor output), but I bet it's hard to measure let alone hear the difference. The balancing on the monitor output is just done with a resistor from the jack socket ring to earth, so it's just a basic impedance-balanced output as opposed to a symmetrical one; there's no extra amp for this, which is what the block diagram impies - info.
    I think the block diagram is misleading as it implies the DAC output of the monitor stage goes through an additional amp. It would be clearer if the stereo out also showed an amp stage.
    Last edited: Jan 26, 2020
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  5. Saxomohawh

    Saxomohawh New Member

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    Thank you guys. How do you have it connected for mixing?
  6. Phil Tipping

    Phil Tipping Well-Known Member

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    I usually mix on a different system with an analogue mixer, but the same principle applies (for me). The monitor outputs on both systems go to studio monitor speakers. On the analogue mixer, the stereo outputs go to a separate recorder, but the dp machines have a built-in recorder so its stereo outputs are unused.
    If you use active speakers with a TRS balanced input jack, you just need a simple TRS-to-TRS cable to connect the monitor outputs to the speakers.
    Mark Richards and -mjk- like this.
  7. Mark Richards

    Mark Richards Well-Known Member

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    The Stereo Out feeds my main audio reference system: power amp driving 4 paired passive studio monitors.

    The Monitor Out feeds my smaller secondary reference system: a pair of active reference speakers.
    -mjk- likes this.