Mic pre-amp technique?

It depends... I have two mic pre's The Avalon came with a really nice manual that gives some good recommendations regarding what you're recording? For example, for vox, I think you usually want a cleaner sound going in? So there are compressor settings, and EQ settings that are recommended, that's what I go with.

For me, it's typically the Neuman U87AI in to the Avalon 737-VT, in to the Fireface 800. And once the track is comp'ed in, (I'm talking vox) I clone it a few times, put a send on one to a hard comp, a send on another to a delay, a send on another to a chorus, and put the output of all of those to a lead vox bus and use a channel strip there, and send that to the mains. 

It works differently for recording an acoustic guitar, or other things. You should do some trial and error and see what works best for you.

2. So, how do you adjust the end product? Which is best, to gain recording level by cranking the Input, or by cranking the output of the preamp?

Its a balancing act. You do not want to overload the input and you do not want to clip the outputs of your gain staging in the signal chain.
Some preamps give add color to your sound so you may want to pump that up some and not pump up your sound cards preamp if your going threw both. Its give and take until you get the sound/levels you want for that project.
 
Theres no set rules and steps for this.
 
Its been said again and again, but use your ears and do not clip any part of the gain staging. In 24bit recording, you do not need to record a signal at -3dB. Anything form -16dB to -6dB is great
Cj

montezuma


I don't think that really answers his question. I don't think he was asking about what you do with your Neuman, Avalon, Fireface...or comping, cloning, putting sends on, delay, chorus, panning, channel strips, compressor settings, eq.......As interesting as all that is...he wants to know what to do with level...should he be cranking the Input, or cranking the output of the preamp...you just told him you get settings from the manual. So, if you have time...post again coz I want to hear what people have to say about this topic too.

Well alright den. I crank the input low, and the output higher (to get the level) when recording vox? Typically the output not too high, up to neg 12. And higher on the input and lower on the output to get a warmer sound for something like bass? How's that? Higher input, lower output for more of a tube sound, or a pre-amp'ed sound? Opposite for more of a cleaner sound?

But I still recommend the "Neuman, Avalon, Fireface...or comping, cloning, putting sends on, delay, chorus, panning, channel strips, compressor settings, eq......." thing.

All of the preamps in my rack put out 24dBm before clipping while the MOTU 896 I use to digitize can handle about 16dBm before clipping.

I use the knobs on the preamps to make the signal sound nice... and then I make sure the signal doesn't fry the MOTU.

It's easy.

No need to worry about a monitor level calibration protocol while tracking... you should control your monitor levels over on your monitor system.

best regards,
mike

Another random thought...

My API 3124+ only has one knob per channel.

And it came with an instruction manual :-)

My Grace Designs pre has an LED light which is used to monitor the input level.  I use that as a reference for setting the input level and then adjust the output level to get a decent signal in SONAR.

The answer to every question on the forum. Middleman, you're a genius.

Thanks everyone for the replies.

What I've been doing is doing what some suggest, balancing till it sounds OK, but I have lost of what good is after a while.

I think my mind saturates and, anyway, "good" kind of needs to be compared to something else, and I do have trouble keeping one quality in mind while hearing another one real time, so settings as this has made me ask this question.

I checked briefly on the K system that Jeff mentions, and what he explains is what I was hoping to read about, without much pretense.

When I started learning a little over a year ago, or so, I was under the impression that I would move the knobs and just leave them there forever. How naive.

I thought the input was to match the microphone, and the rest was volume, but obviously that's not all there's to it.

Then, on reading about the K-system that Jeff mentions, they do talk about "matching impedances", so maybe that's another factor, so I'll see if there's some more info on that.

I also read somewhere, after I posted, that this issue can indeed get rather technical. Like, for instance, I read about for real important events engineers spend up to two days calibrating things and setting the levels. But elsewhere, I read that most good engineers can do those things without any parameters, just with their experience with the equipment they are using.

I incline for something like that...Have some technical basis on the equipment one has, or what one is doing.

And the truth is so far I find it hard to distinguish when I make the adjustment with the input, or do it with the output...And that's where I want to clear up on, to some degree.

Thanks everyone, again.

Ahhh...Jeff...my last comment was dripping with sarcasm. Sorry middleman.

Thank you Jeff, and Middleman for your new comments, which are indeed helpful, as well as those of others.

Jeff, I have currently three lower cost mic preamps. Two are mixers with pre-amps. One is in a 200 watt amplified mixer called Europower PMH1000, a smaller mixer/preamp called Xenix-802, and a preamp only called Tube MP-Studio. The first one I use only as amplifier, with all settings on neutral. The amp feeds 2 large Klipsch 3-way speakers, old ones, from the Hi-fi years, and also two smaller Infinity ones from the same times. I don't have monitors..I have set the speakers to sound as close as possible to the AKG-headphones, as to low and high frequencies, and as to hearing about the same on headphones as in speakers, specially on instruments. I adjust the high frequencies with the smaller Infinity ones, which are actually fed from an Altec powered system (I just removed the even smaller speakers and connected the Infinity ones in place). That also gives a subwoofer that is part of the Altec. So that's how I kind of get similar sound as from the AKG headphones, overall, but not exactly, of course.

I use two microphones, alternatively. The better one is an AKG-C535EB which is kind of a trade-off between a condenser-studio and stage type. It uses 48 VDC, and has a switch with 4 settings.

The other mic I use is a Telex brand unit that I have concocted into a neck-brace which I use as I play the keyboard..This is to help when I move the head, so the mic is generally close to the mouth...That one is electrect type and I put two 1.5 batteries in series for bias. The batteries are away from the mic, so the mic is very light. (On that one, I concocted a wind-screen made with pantyhose material). The AKG is mounted on an adjustable structure, and I am still not learned into playing the keys and keeping a constant volume on it. But the up-3db, or down-3db tedious task is a good motivation to improve voice-projection,  and I believe I am improving a little, to avoid that. Yes, editing the vocal waves is a good teacher, for me.

I believe somewhere the Xenix or the Europower said to put the dials in the middle, with not much further explanation..So, for a long time that's was the criteria for me. Moving sometimes a little, either input or output. Now those two actually also have a third way to increase the signal, which they call Main-Mix. I don't move that one, as I recall. I don't use currently any other external sounds, other than mics, and sometimes my flamenco guitar, or the harmonicas. My usual playing is keyboards, I use two: lower and upper manuals.

After reading all of the people's posts, yesterday, I did some simple tests, and found that I in general have (maybe) been setting the signals low.

Another way I had been guiding myself is observing waves-shapes of songs I like, and watching the difference from the voice to the accompaniment, typically on simple songs that I relate to, and then, on a blind-way, kind of try to get similar shapes of mic to music relationship...Also, I kind of use them as guides for magnitudes, or overall volumes...But I am interested in using "references" or "pink noise", as I have just read in searching for K-systems. That will be slow for me, though, I gather.

Also, lately, that I have been learning on VST's that provide ambience, resonance, compression, normalization, and so on, my mind and hearing do get confused, as to what is best as to settings of hardware knobs.

So, what I am after is some basic criteria (technical if possible) to set those gains to begin with, and I believe that with the advise so far, I have more than plenty to settle that.

I have not gone yet into the details of the K-system, but I believe the principles are manageable, and hopefully will help un-confuse me.

As to the quality of the pre-amps, I believe I am the limiting factor, rather than them, so I am putting off getting any thing better so far, but not rejecting it, either. I like the fact that some preamps don't have but maybe one control..That makes sense, since so much can be done with internal software, nowdays. And I do catch the explanations of the input adding color, distortion, and that it may or not be what one wants...And those things can be done with software too!...So all those controls I have (including some EQ knobs in hardware I do have them all in the center, by the way).

It seems to me that basically everyone is explaining somewhat the same principles, in different ways. The different explanations, I find, help unify the fundamentals things I still need to grasp. So I appreciate each and every one's.

Thanks everyone.

Thank you Jeff.

I find this a good guideline and I am already trying to figure this out.

If not too much asking, would you give some sketch as to how to set the faders or knobs to unity gain? I have the following to start with. Do I use the mic's output db's specs as a starting point?

Each Trim knob on top of each channel has a range of [+10]10 ccw and -40 [+60] cw.  I suppose the one value is for XLR and one for 1/4 jack.

Each corresponding LEVEL knob has a range of "infinity" ccw and +15 cw. The MainMIx Knob has the same range as the LEVELs.

Thanks.

Hi Jeff,

And thanks...I will study this on and on till I get it.

(I edited my previous post, before this reply explaining Unity Gain..So, please disregard my editing).

Very grateful.