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    that gosh darned signal to noise ratio


    Hi guys. I'm hoping you can help me. I'm using a Fostex FR-2 and a Rode NT-4, not the quietest set-ups in the world but not bad either.

    In the Sound Effects Bible, the book reviewed in another thread, it says that ideal recording set-up is to have your master fader at eight o'clock and your trims at around two o'clock. Well when I follow this advice I have a really hard time getting the metres to move beyond -30 db even for sounds that are loud like vacuum cleaners, toilets flushing etc, so recording quieter sounds like laptops, birdsong etc is a difficult proposition to say the least. . I've also been told on more than one ocasion to adjust at the trims. Well to get the metres moving between -20 and -12 DB I have to pretty much max the trims and sometimes turn the master fader up a bit as well.

    Sigh. Now I've also been told that turning gain knobs up to their max point is a bad idea. So, what's going to be least damaging to my audio? To have the master fader higher than eight, to keep the master fader there and max the trims. Or to have the trims down a bit and the master at eight and apply something like 20 DB of gain in post?

    Thanks in advance.

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    I don't know if you've seen this or not, but perhaps your mic has the [http://www.freesound.org/forum/viewtopic.php?p=23890]built in cable pad. Else perhaps your record's sensitivity is turned down by accident (I don't know if there is a menu choice for something like that)?

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    Nope no mic pad, the switches are set to mic not line and the only other two places to adjust volume are at the trims and the master fader. I've seen a few other reviewers complain that the pre-amps on the Fostex don't offer a lot of gain. I just want to know what's the best way round it. Don't have the money to upgrade to a Sound Devices 702 yet and anyway I only just bought this so want to get my money's worth and, anyway, I'm pretty sure it's something I'm doing. Like I say, just knowing, where I should apply the most gain would help. I mean eight o'clock seems kind of low to have the master fader set at but someone seems to think that's the unity gain position.

    Lol I'm just tying myself in knots. Anyone with any other thoughts what the cleanest way to boost my signal would be?

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    It's always tough on these units that don't indicate gain levels clearly on the trim and faders. The 8 o'clock suggestion seems appropriate for the trim for getting around 0dB considering the trim's range is -60dB to +4dB. The challenge with this unit is there is no indicator on the fader for what amount of gain is being applied. Depending on the mic you're using, 0dB on the trim might be too much gain before the fader. The standard practice for setting a level is to set the fader to 0dB of gain and then adjusting the trim upward until the levels look good in reference to the mic's position and the loudness of the actual audio source you're recording.

    The best way to figure out where 0dB of gain is on the fader is to run a tone into the input of the recorder. But this still requires knowledge of how dBu translates to dBFS on the recorder. Generally 0dBu will translate to -20dBFS on digital recorders, but that's not a rule. Assuming that's true of this unit, you could try: Running a 0dBu tone into the recorder at mic level; Setting the recorder's input to mic; Setting the recorder's trim to 0dBu (About 8 o'clock I'm guessing). Turn the fader up until the meter on the recorder reads -20dBFS. That is the fader position that (Presumably) is 0dB of gain. Knowing that position, you can set levels by first setting the fader to that position and then putting the trim arbitrarily wherever the levels look good.

    Good luck! smile

    Nic Stage - Field recorder organism
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    nicStage
    It's always tough on these units that don't indicate gain levels clearly on the trim and faders. The 8 o'clock suggestion seems appropriate for the trim for getting around 0dB considering the trim's range is -60dB to +4dB. The challenge with this unit is there is no indicator on the fader for what amount of gain is being applied. Depending on the mic you're using, 0dB on the trim might be too much gain before the fader. The standard practice for setting a level is to set the fader to 0dB of gain and then adjusting the trim upward until the levels look good in reference to the mic's position and the loudness of the actual audio source you're recording.

    The best way to figure out where 0dB of gain is on the fader is to run a tone into the input of the recorder. But this still requires knowledge of how dBu translates to dBFS on the recorder. Generally 0dBu will translate to -20dBFS on digital recorders, but that's not a rule. Assuming that's true of this unit, you could try: Running a 0dBu tone into the recorder at mic level; Setting the recorder's input to mic; Setting the recorder's trim to 0dBu (About 8 o'clock I'm guessing). Turn the fader up until the meter on the recorder reads -20dBFS. That is the fader position that (Presumably) is 0dB of gain. Knowing that position, you can set levels by first setting the fader to that position and then putting the trim arbitrarily wherever the levels look good.

    Good luck! smile

    Sorry for the noob questions but how do I create a 0 Dbu tone? Also, I have the master fader at eight initially when running these tests but where do I have the mic trims? Having found the level on my master fader that gets the metres hitting -20 DBFS, I set my fader to that and go out and record. What do I do if what I'm trying to record requires more gain than the mic trims provide? Is it better to increase the master fader or increase in post?

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    Yeah it's an Fr-2 not Le. I'm glad that other people have had the problem and it's not just me. Guess I'll just have to focus on recording louder sounds until I have the money to get an outbord pre-amp or a field recorder capable of recording quieter sounds. Gain-staging tips so I can get the best out of what I've got still welcome though.

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