"Location sound 101 - This is how it is"

in simple words - the line level on microtrack cant handle full signal your mix pre can deliver ( about 22 dbu before It start distort) - so you need attenuate the output to match your recorder

1/4" Mic/Line Inputs

Maximum Input Level: +4.3dBu, balanced; +2.1dBV, unbalanced

the maximum level your mixer suply before distort is 22 dbu



for unbalance out from mini pl on mixpre 6 db attenuation will be fine and not as i did write before 10
to work normally and still have the 8-10 db headroom with your packs you have to calibrate the microtrack for-20 dbfs after you insert attenuation , if you calibrate it now you probably blow your input( distort) before the mixer distort - that shouldn't happen
the 30v issue on the microtrack is not the only thing thatsucks:-)
the m- audio did not provide normal line input and its quit limiting if you go with -10dbv signal as well - then you are working on the age since the mixer defiantly will giveyou 5-6 db more before your input will distort - so if you don't wont to make pads and work from -10dbv out - you mast see the +12,14 point on your mixer as the highest point that you cant go over and calibrate the mixer limiters on +10 db - stupid isn't it?
like droog sad these devices have different scales - the microtrack use the same as your dvx - dbfs( db -fullscale) which starts at 0 and going down - the 0 is digital zero which is the highest point you can record , since microtrack has hard limiter on analog to digital stage it wouldn't go over and will not bring you to digital distortion but it would show already distorted level if you came with grater signal in the input
the mixer has dbu scale so you tone is is on 0dbu and your peaks should be +8+10 for normal working
if that was normal equip i was calibrating the 0 db from your mixer as -16-18 dbfs
since it is not normal you have to match this with attenuation
its very simple to make attenuation cables , jay rose have the schemes on his site
always try run balance signal , its good to prevent ham in your setup from ground loops
 
Matt and Droog - I think, and Im by no means an expert here, that you guys are talking about the difference between a normal (1k?) and a FULL SCALE tone. I know that the 302 and maybe the Mixpre (FP24) can deliver an uber-hot tone that will match up exactly on the scales of the cam.

I could be wrong, Ive never tried this, just read it in the manual. For full scale, 0 on the mixer would be 0 on the cam?

Am I being dumb?

ALSO one other thing, sometimes I find when Im shooting that+8 for the peaks is sometimes hard to get without cranking the mics to full! Whys that, Im not too far away with the boom usually... Using a 4073a too, so the mic is hot... Comments?
 
to change the ton have nothing to do with calibrating missmatch on you recorder inputs ,the benefit of 302 is to decrease the output level while you still see the right levels on your meter before the general attenuation .
the tone change good for calibrating the ref for editting purposes - like you did for150

check where are your preamp had been set
for 10 mv mikes as schoeps the preamp is about 4 o clock in normal conversation boom about 1-2 feet over
for 4073 you have to be about 18 db lower on your input stage
if it is not like that might be something wrong with the mixer
 
4o'clock meaning almost full on the input gain knob (preamp?)?

im always kinda scared to push the preamp that high..
 
4 oclock - yes its less then the end but its there :-) about 50 db
check the loudness of you recording and adjust that the pick level indicator will hit on the strongest signal ( if iam not mistake its 3 db before clipping)
there are different amplifying gain structure on different mixers , some like audio development amplifying the signal first to the maximum and then you decrease the signal with the fader , some have steps( wendt ,sqn) and then aditional gain on the fader , some have continus gain as SD
 
I'm sorry if I'm not being clear... and I hope George will step in if he thinks I'm giving bad advice. If he corrects me I'll go back and edit my posts to be more concise. I don't want to pollute this good thread.

If I setup the 1kHz test tone on the fp24 the mixer is at 0db... and if you put on phones at the normal listening level it sounds LOUD. I haven't had the fp24 and 671 long enough yet to be an expert on it, but in my limited experience I find that keeping the levels below zero, even on the fp24 has worked out best for my sound. Why is this? Because I set up my recorder to be below zero, as I was saying before... then all I have to do is watch the mixpre. In one of my posts a ways back I said something about setting the recorder 12db down... and I was guessing at a safe setup, but that's what Tim is saying right? That makes sense but I've got my best sound by zeroing both machines and then just keeping levels under 0db on the fp24.

What George is saying about the MicroTrack is what you mentioned earlier in the thread Jon... and that is you need an attenuation cable since you have the fp24/mixpre... the 302 includes a feature to attenuate the output because there's a pot/pad built into the mixer... and you need to mimic that with the -20db cable. Then all should be right with the world. Still, without something on the MicroTrack to indicate a 0db clipping level I can see where it would be hard to set up. There's got to be something on there to tell you what's happening.

The other thing is your recordings are sounding great... so you must be doing something right.
 
how do you connnect your 671 ? pl-mini to rca ?
xlr outs to xlrs with pad down 20db?
i didnt work or checked the 671 to say wjhat is the best deal for it

does it sounds bad on the mixer when your picks go over the 0?9 mixer not recorder and not mixwer return)

the setting have to be 0 tone on your mixer =-16 ,-18 on the recorder dbfs scale
while the evereg recording around -10dbfs
 
Thanks george, Im going to try that out...

Ive been thinking about it Matt, and at the end of the day, -12, -20, 0, its all just about how much headroom you're trying to give yourself... I guess for broadcast its a no-nonsense business and thats why levels around -20 for safety are set up:

I know for a fact that recording as close to 0dbfs as possible without clipping is the ultimate level to record at.

-12Dbfs a safe setup?yes. And this is a good thread? Yes... so Ill shut up now. :)
 
Exile, ok I am on the same page with you now. I see the point you are making about needing pads. The problem is that the micro track is essentially consumer and distorts at +4 dbu, wonderful. Alright so pad your signal, I still advocate setting reference tone for -20 dbfs. That has been an industry standard for me. Now, you guys do what you want, sounds like most of you are doing your own productions and and for sure, if it sounds good it is good, but ultimately I cannot afford to not give the person paying me what they want, how they want it.

Also Exile, yes your suggestion for finding -20 is spot on, though I don't think that is possible with the FP24 as its meters do not go that high. The 302 would do it, yes?

The reason -20 is used to equal 0 dbu is not so that your content is at -20, yes it gives you that 20 db of head room, but ideally your analog signal is going to be well over 0. So if your content is living around +5 or +8 dbu then you have a good 13 db of headroom for peaks before you start distorting your digital recording device. This is pretty standard procedure for field work. Now in the recording studio its not uncommon to calibrate DATS to -12, but that is a controlled environment and a different beast all together.

I apologize if I have added to the confusion, though it is not that confusing. In the end the Micro track is not a profesional recording device and we have to make allowances for this, the 302 is the way to go because of the output attenuation. Calibrate however you will but like I said, you need hot signal in the analog world and hot signals in the digital world, not one or the other.
 
This thread has really helped me a lot so far. I think I was running too close to the wire. I was trying to balance the fp24 with the 671 and then avoid riding levels, but found I was forced to. I'll try setting it up like you suggest and see what I get. The reason I was trying to run the 671 hotter and the fp24 lower was because I've noticed a strange characteristic of the 671. When I'm running stereo mics in an ORTF configuration I notice a super-wide soundstage directly out of the fp24... then when I switch to the monitor (671) the stage gets HALF as wide. If I turn up the 671 and bring down the fp24 it's not nearly as bad. I realize that the fp24 has way better channel seperation then the 671, but all I know is the soundstage is wider if the 671 is running higher gain. Does that sound strange to anybody?
 
MattinSTL said:
This thread has really helped me a lot so far. I think I was running too close to the wire. I was trying to balance the fp24 with the 671 and then avoid riding levels, but found I was forced to. I'll try setting it up like you suggest and see what I get. The reason I was trying to run the 671 hotter and the fp24 lower was because I've noticed a strange characteristic of the 671. When I'm running stereo mics in an ORTF configuration I notice a super-wide soundstage directly out of the fp24... then when I switch to the monitor (671) the stage gets HALF as wide. If I turn up the 671 and bring down the fp24 it's not nearly as bad. I realize that the fp24 has way better channel seperation then the 671, but all I know is the soundstage is wider if the 671 is running higher gain. Does that sound strange to anybody?
Click to expand...

That does sound strange, but it could also be that its the headphone jack/amp on the 671. I would bet that everything is getting recorded right but the monitoring is deceiving. When you load it into your NLE how does it sound? Also keep in mind that the better your signal is on your 671 or any digital device, the higher the quality will be, more resolution. I would imagine that the monitoring of 671 is not the most reliable. Also make sure that both your channels are still in phase, its possible that for some reason, one channel is out of phase with the other at the 671 and that will drastically alter your stereo image. Sometimes you gotta just trust your skills and equipement, because location is not always an ideal place for critcal listening.
 
Guy!!!, parle you Chinese, me not understehen nothing!!!

Ok I'm going to try to bring this thread back in to the 101 realm as i don't have a clue what you are talking about, that surly being my own fault.

Anyways, what I'm wondering is when we talk about ideal signal, noice...it would be nice if we can discuss it relative to the tests as it gives a practical illustration of what you are saying, and the chance that i may be able to understand and follow is somewhat improved. Remember baby steps, baby language, we are at the 101 level here. :huh:

So as i mentioned before i made an unbalanced cable to run from the mixer to the M-Audio recorder. When i record dialog what i have bin doing so far is speak in to the microphone and adjust the levels so that the clip signal on the Micro-track stops blinking. This puts me at more or less -15 db on the mixer, although i fell that the sound in my headphones which are running from the mixer on the highest setting is to present and sounds almost forced as you will hear in test's #005,006,007.
The levels on the M-Audio look good, not clipping but dancing around the middle of the scale, occasionally reaching close to the top.

Can you guys comment directly on those tests and come up with suggestions how to improve?

Is this cable that i made a -20db cable?

thank you :thumbsup:
 
This is location sound test
#005,006,007

TEST#005

TEST#006

TEST#007



LS#005
Octava 102a (from 1.5 feet, no wind protection)
Shure FP24 (levels set to -15db, 80hz filter on)
M-Audio Micro-track (recorder)

Same conditions as in test #002

I's this sound distorting?



LS#006
Countryman B6 wired (modified)
Shure FP24 (levels set to -15db, 80hz filter on)
M-Audio Micro-track (recorder)

Same conditions as in test #002



LS#007
Countryman B6 wireless (modified)
Senheiser G2 (wireless unit)
Shure FP24 (levels set to -15db, 80hz filter on)
M-Audio Micro-track (recorder)

Same conditions as in test #002

Is the wireless signal good?
 
Basically they are speaking basic 101 dB speak. Since you do have Jay book and we are treating this as a classroom Jay's book should be our textbook. The assigned reading is pgs 55 thru 58 in our text book (had to break it out but if we all have the same reference this will save time).

To anyone who doesn't have Jay's book and is seriously trying to understand audio, go get it. People can type on this forum until our fingers fall off, all the key information to getting started is in this book.

In particular you will see on those pages a section called "Cross-connecting -10dBV and +4dBu equipment". I was unaware but I guess Excile is saying the Microtrack is consumer -10dBv. The Mixpre/FP24 only outputs +4dBv. So the key idea is you need to pad the signal down to -10 in order to not get distortion.

As for your clips, I can't download them for some reason.

Best
 
I can't open any of those, probably my machine, but it just ends up at "sorry" page at .mac. Also the thing about having mp3 tests is that they are not the best way to determine good from not so good. Also, most people do not have the greatest speakers or sound card on there internet compy. What I am saying is that it may be hard to determine what is making a recording sound bad when monitoring in a deceiving fashion.

As far as that unbalanced cable goes, I doubt if it is -20. Simply unbalancing a cable does not make it -20. Seems to me that balanced is going to be preferable anyway, if I remember right the Micro Track distorts at +2 unbalanced, but at +4 when balanced.

Maybe something like this Shure A15LA would do the trick. Its a little excessive at 50 db, but I imagine you could compensate at the Micro Track.
 
Wabbit,

I'm hearing you and like the way you want to aproch this, i will now reread those pages of a truly grate book. The only reason why i started this thread though was that although the book is very clear and in reasonably plain language, it covers a more general V.S specific explanation relating to this equipment. And while all the comments here are grate and sound like they are coming from people that really know what they are talking about, i think that people in my situation (no experience with sound, but common sense) will benefit more from a less extensive explanation and a more hands on approach. Maybe changing one thing at a time rather than giving a general "this is how you do it" type of answer, as thats when i completely lose you.

"If you could say something like test #005 seems to noisy, so try bringing the mic closer and get a cable like this .....(link if possible) as this will do this.....than try again."

That would be loads of help :thumbup:

As for tests, try again! I had no problem downloading!

And Droog, as mentioned before, this thread is probably not gona be of grate benefit for people that don't have professional monitoring headphones.
 
Get ready for picture-a-thon 2005!!!

FP24 setup 1.jpg
 
Yes, tilting you head while the mic is angled sideways doesn't replicate the vertical positioning of the mic because it's aimed at the wall.

Lesson learned from 001: Location and orientation is KEY.

To learn more;

A: go to my site. click on the location audio link, read "The Letter."
B: When you make a test, make sure you don't side step reality as you did by positioning the mic sideways.


Boom on young skywalker,


Ty Ford
 
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