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Gear / Technical Help => Battery Boxes, Preamps, Mixers, ADCs, and Processors => Topic started by: Teen Wolf Blitzer on February 28, 2006, 06:30:22 PM
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Way way way better volume on the headphone jack. Big improvement. I think so anyway. I've seen Nicks Picks say it the same. No way I say.
Also on the R4 interface it shows you all 4 channels with levels and a clip indicator. What do the other level meters represent on the lower right hand corner? I think they say line out levels?
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Also on the R4 interface it shows you all 4 channels with levels and a clip indicator. What do the other level meters represent on the lower right hand corner?
They're an average of the 4 meters, good for if you were running a 4 channel BWF, otherwise useless.
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Way way way better volume on the headphone jack. Big improvement. I think so anyway. I've seen Nicks Picks say it the same. No way I say.
Also on the R4 interface it shows you all 4 channels with levels and a clip indicator. What do the other level meters represent on the lower right hand corner? I think they say line out levels?
The headphone volume is much stronger on the r4 than the ua-5. Quieter too.
JAson
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Also on the R4 interface it shows you all 4 channels with levels and a clip indicator. What do the other level meters represent on the lower right hand corner?
They're an average of the 4 meters, good for if you were running a 4 channel BWF, otherwise useless.
Ok because it was weird all four levels were good..no clipping at all but those two on the right were clipping. It sounded good so I didn't worry about it. Weird though. I can't find a thing in the manual at all about them.
Also is there a way to turn down the input on say line in channels 3 and 4? My mics were good...about 11 0clock but the board patch was turned all the way down and the levels were a little higher than I liked but nothing could be turned down on the crappy board. I tried. Maybe a pad is what I'm thinking of?
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Those two lower-right level displays are for your output levels, i.e., the gain level seen at your digi/coax out, and rca outs.
You may turn those two lower right levels down by accessing the display button, twice. Then you can select wichever channel is clipping, utilize cursor/monitor select. Then use the scrub/value dial and lower the value. This only affects the output gain, not what is seen at the input to the R4.
FYI factory settings are for a gain value of 100/110 default.
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This brings up a newb question for me actually. Say you were recording 4-channel for a known 50-50 matrix in post. Should you record both stereo pairs at their optimal levels (close to clipping without going over), then when mixing turn them down so when added together they don't clip? Or is it better to leave headroom during aquisition on both stereo pairs so when you mix in post they add together and don't clip. My guess is for noise floor reasons, you'd always want to do the former, but honestly I'm not sure, curious though.
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This brings up a newb question for me actually. Say you were recording 4-channel for a known 50-50 matrix in post. Should you record both stereo pairs at their optimal levels (close to clipping without going over), then when mixing turn them down so when added together they don't clip? Or is it better to leave headroom during aquisition on both stereo pairs so when you mix in post they add together and don't clip. My guess is for noise floor reasons, you'd always want to do the former, but honestly I'm not sure, curious though.
If you are recording in 24-bit, whether you are matrixing or not, I would highly recommend leaving more headroom, there simply is no need to crank the gain past -12 dB, the extra dynamic range you get is theoretically not as much as you think it is, somebody put some numbers on this board explaining why, but I forget them and where they are. If you are recording in 16-bit, it is up to you and your preamp whether the extra noise introduced is worth it to get your peaks up to -3 / -5 dB.
When you know that you will be mixing two different stereo signals in the post, I would say that there is no need to push the gain (and risk clipping and extra noise) when you know that you would have to attenuate in the post just so you can mix the two signals later. However, I will try to get optimal levels (based on my comment in my first paragraph) on the aud feed if it is onstage (which it usually is for me), just so I can capture the wonderful onstage dynamics as purely as possible, and I'll leave the sbd feed relatively safe and low. If it's a PA, I still try to get somewhat optimal levels but I'm much more reluctant to push them as high as an onstage recording.
These are just my experiences/preferences, I hope someone who has a lot more experience and knowledge will offer their point of view.
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Can the signals sum to a higher peak than either has individually?
example
track A peak = -3db
track B peak = -2db
I would assume the sum (A+B) peak would be -2db?
Can it sum higher?
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I cannot explain the numbers, all I know is that when I would mix down two files, neither of which were clipping (but close to 0 dB), the end result was a file that is clipping.
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i still think it sucks.
If I cant hear it on my headphones durring a show, then I dont like it.
Ety's...need not apply. those make any headphone amp sound fine. try driving a pair of Senns w/it.
yuk!
sucks comparred to the FR2. now THAT was a headphone amp. the DAP1 also was way better, imo.
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Can the signals sum to a higher peak than either has individually?
example
track A peak = -3db
track B peak = -2db
I would assume the sum (A+B) peak would be -2db?
Can it sum higher?
Yes it can sum higher. After all 1+1 sure is 2.
If you add two identical signals the sum is +6dB up.
I would expect adding -3 + -2 to end up at around 0 to +1dB.
Gunnar
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Yes, the sum will actually be higher. There's some math that will let you figure out exactly how much. Decibels (dB) are a ratio and can be used to represent many things from power to voltage to acoustic sound pressure level. The relevant equations are 10 log E2/E1 and 20 log P2/P1. experiment with sine waves in a DAW and see what happens.
http://www.hottconsultants.com/techtips/decibel.html
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This brings up a newb question for me actually. Say you were recording 4-channel for a known 50-50 matrix in post. Should you record both stereo pairs at their optimal levels (close to clipping without going over), then when mixing turn them down so when added together they don't clip? Or is it better to leave headroom during aquisition on both stereo pairs so when you mix in post they add together and don't clip. My guess is for noise floor reasons, you'd always want to do the former, but honestly I'm not sure, curious though.
If you are recording in 24-bit, whether you are matrixing or not, I would highly recommend leaving more headroom, there simply is no need to crank the gain past -12 dB, the extra dynamic range you get is theoretically not as much as you think it is, somebody put some numbers on this board explaining why, but I forget them and where they are. If you are recording in 16-bit, it is up to you and your preamp whether the extra noise introduced is worth it to get your peaks up to -3 / -5 dB.
When you know that you will be mixing two different stereo signals in the post, I would say that there is no need to push the gain (and risk clipping and extra noise) when you know that you would have to attenuate in the post just so you can mix the two signals later. However, I will try to get optimal levels (based on my comment in my first paragraph) on the aud feed if it is onstage (which it usually is for me), just so I can capture the wonderful onstage dynamics as purely as possible, and I'll leave the sbd feed relatively safe and low. If it's a PA, I still try to get somewhat optimal levels but I'm much more reluctant to push them as high as an onstage recording.
These are just my experiences/preferences, I hope someone who has a lot more experience and knowledge will offer their point of view.
Isn't there a balance here though? I mean, yeah, if you are maxing out the gain on your preamp, most likely you are introducing a bunch of noise, so of course you wouldn't want to do that. But on the other hand, if you apply way too little gain, the recorded music's volume will be down closer to the noise floor, so when you normalize in post, you'll be bringing up both the music and the noise floor together. So, it seems to me, there is a sweet spot.
My take on this is that you should apply gain as far up until the point of clipping (but obviously NOT clipping) as you can as long as you aren't maxing out your preamp to the point it starts getting noisy. For concerts, this is usually pretty easy to do without going too far on the gain. This results in the recorded music being as far above the noise floor as possible in your recording. Then, if you are mixing two sources, you'll have to reduce the levels such that the sum of the two sources don't add up to a clip. But even though you have to reduce the volume during the mixdown, at least you are preserving the spread between the recorded music and the noise floor. Again, only if you don't have to crank the gain past your pre's ability to add lots of noise.
Doesn't that make sense? Or am I missing something here?
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This brings up a newb question for me actually. Say you were recording 4-channel for a known 50-50 matrix in post. Should you record both stereo pairs at their optimal levels (close to clipping without going over), then when mixing turn them down so when added together they don't clip? Or is it better to leave headroom during aquisition on both stereo pairs so when you mix in post they add together and don't clip. My guess is for noise floor reasons, you'd always want to do the former, but honestly I'm not sure, curious though.
If you are recording in 24-bit, whether you are matrixing or not, I would highly recommend leaving more headroom, there simply is no need to crank the gain past -12 dB, the extra dynamic range you get is theoretically not as much as you think it is, somebody put some numbers on this board explaining why, but I forget them and where they are. If you are recording in 16-bit, it is up to you and your preamp whether the extra noise introduced is worth it to get your peaks up to -3 / -5 dB.
When you know that you will be mixing two different stereo signals in the post, I would say that there is no need to push the gain (and risk clipping and extra noise) when you know that you would have to attenuate in the post just so you can mix the two signals later. However, I will try to get optimal levels (based on my comment in my first paragraph) on the aud feed if it is onstage (which it usually is for me), just so I can capture the wonderful onstage dynamics as purely as possible, and I'll leave the sbd feed relatively safe and low. If it's a PA, I still try to get somewhat optimal levels but I'm much more reluctant to push them as high as an onstage recording.
These are just my experiences/preferences, I hope someone who has a lot more experience and knowledge will offer their point of view.
Isn't there a balance here though? I mean, yeah, if you are maxing out the gain on your preamp, most likely you are introducing a bunch of noise, so of course you wouldn't want to do that. But on the other hand, if you apply way too little gain, the recorded music's volume will be down closer to the noise floor, so when you normalize in post, you'll be bringing up both the music and the noise floor together. So, it seems to me, there is a sweet spot.
My take on this is that you should apply gain as far up until the point of clipping (but obviously NOT clipping) as you can as long as you aren't maxing out your preamp to the point it starts getting noisy. For concerts, this is usually pretty easy to do without going too far on the gain. This results in the recorded music being as far above the noise floor as possible in your recording. Then, if you are mixing two sources, you'll have to reduce the levels such that the sum of the two sources don't add up to a clip. But even though you have to reduce the volume during the mixdown, at least you are preserving the spread between the recorded music and the noise floor. Again, only if you don't have to crank the gain past your pre's ability to add lots of noise.
Doesn't that make sense? Or am I missing something here?
I agree with this, but if you can get the right mix w/o having to make adjustments in post, you are in the best case scenarion (good use of the output meter defaulted to -0-). Good luck with that though! You definately don't want to spend a lot of time riding levels on a multi... it just isn't worth it. Set it and forget it unless you are looking at a clip. With my r4 I find myself leaving a fair amount of headroom. I try to get it to dance around the -9db mark (at show start) when doing a 4 track recording, but I try to keep it hot when doing 2 chan. With a 2 chan recording I don't mind riding the levels a little bit, although, like the ua5, when you get past 12 o'clock, the pots are super sensitive, so be careful with the movement.
And yes, as other's have stated, mixing 2 similar sources together will increase output level. That is only perfectly true with a full range signal like white noise, or an exact duplicate signal like a test tone. Music is neither. If you have one source (i.e. sbd) that is all mids (vox) and another source (i.e. stage mics) that has all the low-end and highs (percussion and bass) this wont be true. If you take a recording and run a highpass filter on it and save, then do the same with a low-pass at the same frequency, then mix them together, you will have almost what you started with except where the filter roll-off frequencies overlap... much more to it than 50/50 or 6 db or any other calculation. The only consistants are that the sum equals the whole, and it is different every time. That is why we have ears on our heads, and meters in the software!
Matt
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I try to avoid seeing anything hotter than -10dBFS, period..... 0dBFS in 16 bit is the equivalent of -40dBFS in 24bit, so noise isnt an issue..I dont agree with riding the levels to -0,,..theres just no excuse for having any overs.
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So the acoustic phenomenom of phase cancellation and reinforcement are not in play...it doesnt work the same way in the electrical world?
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I try to avoid seeing anything hotter than -10dBFS, period..... 0dBFS in 16 bit is the equivalent of -40dBFS in 24bit, so noise isnt an issue..I dont agree with riding the levels to -0,,..theres just no excuse for having any overs.
You are loosing me here Teddy. The noise is from the analog end not the digital. How does this differ. the pre's are the same either way.
Matt
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So the acoustic phenomenom of phase cancellation and reinforcement are not in play...it doesnt work the same way in the electrical world?
I'm not sure what you are saying either.
Matt
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one thing about recording in 24bit ..yes, you can have great dynamics and detail with a "shallow" signal that peaks at -12db.
OTOH, you have to have MASSIVE power in your playback system to get that to reproduce back at the same volume as the actual performance.
this said, there is no harm in ridding a little hotter. I try to get my 24bit stuff to peak at around -2db...but hitting 0db doesnt hurt anything.
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i still think it sucks.
If I cant hear it on my headphones durring a show, then I dont like it.
Ety's...need not apply. those make any headphone amp sound fine. try driving a pair of Senns w/it.
yuk!
sucks comparred to the FR2. now THAT was a headphone amp. the DAP1 also was way better, imo.
the ety's will make the output volume of any headphone amp sound fine but they WILL NOT make any headphone amp sound fine. they WILL make any bad headphone amp sound bad. with that said, however, at a loud show, i am not really too worried about how noisy my headphone amp is.
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i still think it sucks.
If I cant hear it on my headphones durring a show, then I dont like it.
Ety's...need not apply. those make any headphone amp sound fine. try driving a pair of Senns w/it.
yuk!
sucks comparred to the FR2. now THAT was a headphone amp. the DAP1 also was way better, imo.
the ety's will make the output volume of any headphone amp sound fine but they WILL NOT make any headphone amp sound fine. they WILL make any bad headphone amp sound bad. with that said, however, at a loud show, i am not really too worried about how noisy my headphone amp is.
I have used both my hd280 pro's and my ety er-4p's with my r4. I prefer the ety's but either is passable imo.
Matt
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That is why we have ears on our heads, and meters in the software!
So long as you have a good set of both! ;)