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Mic In Or Pre-amp To Line-in?

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bisebaer

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Just a question: will it make a noticeable difference if I use mic pre-amps and then record via the line-in instead of using my Rode NT4 mic directly in the mic-input of my MD-unit (MZ-NH900)?

If so, can anyone recommend me a reasonably priced mic pre-amp (or set of pre-amps, since it's for a stereo mic)?

I'm not really in need of a mixing table, since everything needs to be portable, and I'd rather do some mixing on my computer afterwards.

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If you are using the a mic that has a battery power (you put a battery into the mic), then go line in. If you are using a mic without a battery, avoid going mic in for loud music, get a battery box. The loud SPL (sound pressure level) will cause distortion in the MD preamp mic inputs.

I rarely use the mic in on my MD, just for some outdoor sounds that are quiet that I don't mind a little extra noise (from the preamp).

For loud music, you always want to use the line In.

You should avoid using an external battery pack or preamp with most powered mics. The Audio Technica 822 is what I use and I go straight line in with just the AA and I get great results with loud rock. I usually normalize a little with Cool Edit Pro and I am very happy 9/10.

Since the Rode is a powered mic (9v), I would definitely say go Line In for music shows that have any volume whatsoever.

Edited by mrsoul
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Since the Rode is a powered mic (9v), I would definitely say go Line In for music shows that have any volume whatsoever.

Well, I tried it, and it worked OK, at least for the loud organ passages, but some passages are rather quiet, and I had the impression I lost some of the detail (record level was set at highest possible without distortion in loud passages) - or is that just an impression?

Are those powered mics like the NT4 made to go line-in?

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Are those powered mics like the NT4 made to go line-in?

No, they're not.

Powered microphones [with the the exception of some micros that have built-in preamps] are made for use with mic preamps, still. What the power does is make the mic work [condensers need bias voltage so that their element can act as a transducer, whereas dynamics actually induce their own power when hit by sound waves].

The mic impedance of powered mics is usually made to match the same range as that of dynamic mics - that way the same mic preamps can be used for both. Sensitivity &c. are another matter, but still, they're made to go through preamps.

Any mic can be used with a line-in as long as the SPL being transduced is high enough to drive such levels out of the mic [usually this would have to be very loud, i.e. rock-concert volumes]. Line-in, technically, is just another input preamp [buffer] much the same as a mic preamp [usually without 'phantom power' of any kind], but with a different default impedance, expecting a much higher input level as normal. Mixing consoles use the same inputs for both microphones and line-level signals, for example; the main difference there is that you have to turn the channel preamp up for microphones.

In most situations you'll want to use the mic-in for recording 'normal' sounds, unless the microphone has a built-in preamp [which is not usually the case]. If you're recording something extremely loud, you can try the line-in.

The main advantage of using the line-in in loud situations is that the mic preamps on many portables will clip if driven with too high a signal; the headroom added [by none other than what is technically an impedance mismatch] going into the line-in can mean undistorted recordings where the mic preamp may have been unable to cope with the levels coming in.

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Thanks Dex; the reason for my question is that I noticed that in two very loud passages I recorded with the NT4 via the mic-in, show some distortion, although the recording levels were set correctly.

So, perhaps I should invest in some reasonably priced pre-amps?

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Thanks Dex; the reason for my question is that I noticed that in two very loud passages I recorded with the NT4 via the mic-in, show some distortion, although the recording levels were set correctly.

So, perhaps I should invest in some reasonably priced pre-amps?

Giving more slack might work as well. The best way to find out is to just go out with the mic, and see how loud it goes without distortion.

Periodic peaks will exceed 0dBfs in any situation if you don't give enough headroom when recording. Setting levels to what looks safe and then backing off another 'dash' or two on the meters might have avoided the problem.

On the other hand, there are many handy things about having an external preamp. If it's not a problem to afford one, go for it. The advice about headroom still stands, though.

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New member here, making first post with a related question -- hope it's the approprite place. I do broadcast recording for public radio. My mic is an EV RE50N/D-B, and I'm about to order a Hosa xvm 105 cord (the XLR-1/8" stereo mini will fit into the mic and line in jacks on my Sony MD recorder). to minimize noise, and since I don't operate in teh field with a preamp, do you reccomend I use the mic or line-in jack? And if it's necessary, is a preamp feasible in the field?

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The key here is "to minimise noise." Chances are, plugged straight into the mic preamp, the ambient noise level of wherever you are recording will be much higher than the self-noise of the mic or the preamp's own noisefloor.

If you're recording *loud* sounds, go ahead and use the line in. Otherwise, the mic preamp gives you more control over things.

Also, preamps are more than feasible in the field. Take a look on sites like http://www.minidisc-canada.com for an idea of the preamps that are available. Most are roughly the same size as an MD, run on a 9V battery [meaning -much- higher headroom before the preamp goes into clipping], and also act as a battery box should your mic need "plug-in power."

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i have a question....

i just started using my big condenser mic with my HiMD (i had only used the in-ear binaurals that can be powered by the minidisc recorder itself before)

So i have the mic going into a behringer tube ultragain 2000 using 48v phantom power

i use the 1/4 TRS out on the behringer into the line in on my NH900

I understand gain-staging to mean keeping the signal as high as possible all the way through the signal chain without clipping

does this mean i should have the signal coming out of the behringer as high as i can get without clpping on that unit, so the NH900 is recieving as strong a signal as possible? This would mean keeping the NH900's gain on a very low setting, well below unity gain (of course, im keeping the meters on the nh900 as high as possible without clipping)

OR should i set up the signal going into the NH900 so that im using "unity gain" on the NH900?

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I am interested in the reply to that question as well. I am thinking about a different set of mics and a preamp box with adjustable gain. I understand I want the highest signal to the NH900 but do I set the levels high on the NH900 or the preamp output? Looking forward to continuation of this thread.

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does this mean i should have the signal coming out of the behringer as high as i can get without clpping on that unit, so the NH900 is recieving as strong a signal as possible? This would mean keeping the NH900's gain on a very low setting, well below unity gain (of course, im keeping the meters on the nh900 as high as possible without clipping)

OR should i set up the signal going into the NH900 so that im using "unity gain" on the NH900?

I find the best way to run any equipment is to do as close to actual calibration as possible. This is a bit fuzzy with mic preamps, [since there is no unity, just a "standard" amount of gain] though.

"Unity" on the HiMDs is at about 18/30.

If the gain control on your behringer has a centre position, check what its level is on the HiMD when it [the HiMD] is set at unity. Put the mic at a comfortable distance from the source, check the level, then adjust the preamp accordingly until you're comfortable with what's on the HiMD's meters.

edit:

Another point to press, one which I've made before -

Even with a lowly 16-bit, 44.1kHz recorder, the quality is sufficient that you can leave yourself LOADS of headroom [i.e. 20-30dB] and still make a very high-quality recording. Leaving lots of headroom means never worrying about peaking at 0dBfs; you'll likely never get clipping.

Most professional recordists I've seen run with their peak meters riding around -20dBfs. I also do this, unless the situation where I'm recording is predictably loud [like a punk concert] and you know the levels will never get above what yougre already hearing because this is as loud as anything near you can get..

In other words, unless you can predict that what you're setting you peaks at is actually the 'high average' of -everything- you want to record, don't be afraid to crank down that mic gain so that you have loads of headroom to protect yourself from digital clipping.

After all, it's easier to raise the overall volume and apply gentle compression or limiting to the really loud parts later than it is to try to resurrect something useful from a bunch of distorted, clipped garbage.

Running hot is not the best way to do things. If you know you'll be doing at least one pass of editing later, leave yourself a broad margin of safety.

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Just so I am clear in my understanding, Unity gain of 18/30 means there is no amplification of the input? Or am I wrong in that assumption?  Thanks for expounding on that briefly if you have time.

Unity means no gain and no attentuation. If you plug a calibrated line-level signal into the HiMD, a manual level of between 18 and 19/30 gives you measurable unity gain. Mine is off by about -1dB at 18/30.

The idea is that the HiMD should not be acting as either an amp or an attenuator when using it this way. The mic preamp should be given full resposibility as to how levels are set [i.e. use the preamp to do it].

Not all mic preamps have gain controls, so there are obvious exceptions to my opinion on this.

edit:

Note that there are different ways of measuring "unity" gain when digital come into play. What I'm calling unity here is when 0dBVU = 0dBfs; that's when a 0dB volume measurement - of the analogue signal - is equal to the highest level digitally recordable, 0dB full-scale.

There are other ways of doing this. I assume that Sony's convention with consumer electroncis is that -12dBVU = 0dB, sort of like how cassette decks are set with 0dBVU at -10dBV. I tend to ignore the 'peak dash' in the MD's volume meter as anything other than the '-12dBfs mark,' though.

Um. Yeah.

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