Topic: Microtrack Inputs and Headroom

[neutrino]

I was given the specs tonight for the 1/4" and 1/8" inputs which clarified how they can be used, so I thought I would pass it along. According to the MT manual the 1/8" "mic input" can be activated via the switch on the side of the MT to act as a line input, but according to Steve at M-Audio it only has a headroom of -10dbv where the 1/4" activated as a line input has +4dbv of headroom.

As an example to those who were formally using a Sony D100/M1 and stereo mics, the MT 1/8" "line in" mode is not in the same class as the D100/M1 1/8" "line in" which had +4dbv of headroom. So if you ran line in on the D100/M1 to avoid clipping or brickwalling, your most likely going to have to convert your 1/8" stereo mini plugs over to 1/4" jacks to avoid clipping. 

If anyone has anything to add or correct please have at it...
dB-

[udovdh]

I was given the specs tonight for the 1/4" and 1/8" inputs which clarified how they can be used, so I thought I would pass it along. According to the MT manual the 1/8" "mic input" can be activated via the switch on the side of the MT to act as a line input, but according to Steve at M-Audio it only has a headroom of -10dbv where the 1/4" activated as a line input has +4dbv of headroom.

So this means there is only one sensitivity level at the 1/8" input? (-10dbV)

[rdvdijk]

If anyone has anything to add or correct please have at it...

Thanks for allt he info, neutrino. This is an excellent board to pick up knowledge like this.

 I also found this page on wikipedia: http://en.wikipedia.org/wiki/Line-level

Line level is the strength of an audio signal used to transmit analog sound information between audio components such as CD and DVD players, TVs, amplifiers, and mixing consoles. Line levels are stated in units of decibel volts or dBV, and depending on the equipment being used, can vary from -10 dBV to +4 dBV. The most common level used in consumer audio equipment is -10 dBV, which corresponds to a signal of about 316 millivolts RMS. The most common level used in professional audio equipment is +4 dBV, which corresponds to a signal of about 1.585 volts RMS.

So apparently the 1/4" are +4dBV or "professional", and the 1/8" is -10dBV or "consumer".

Roel

[jefflester]

As an example to those who were formally using a Sony D100/M1 and stereo mics, the MT 1/8" "line in" mode is not in the same class as the D100/M1 1/8" "line in" which had +4dbv of headroom. So if you ran line in on the D100/M1 to avoid clipping or brickwalling, your most likely going to have to convert your 1/8" stereo mini plugs over to 1/4" jacks to avoid clipping.

Not really. The reason for running line-in into a D100/M1 is because of the headroom on the mic-inputs not being able to handle the voltage level, not the headroom of the line-level. Sounds like the MT line-in helps close the hole between running mic-in and line-in, where for a quieter show (though loud enough that one worries about mic-in) running line-in (on an D100/M1) with the level at 10 still gives pretty low levels. Sounds like the MT will accept line-in from these types of mics and actually allow for setting better levels.

Now a SBD patch is a different matter. The +4dBv level is typical for SBD outputs, so where previously a D100/M1 could take a normal SBD out as line-in, the MT would need to use the 1/4" rather than the 1/8".

[jefflester]

Of course I also could be full of it, since freelunch has reported elsewhere that DPA4061s into the 1/8" at min gain clipped.