Mic preamp

Started by chip, April 20, 2013, 04:14:12 AM

Hilary

I don't think you can rely on it, mine rarely comes on but I still get clipping - I check my vox in Audacity and adjust the levels accordingly :)
recorder
Boss BR-80

comme ci, comme ça

64Guitars

Quote from: Hilary on April 22, 2013, 12:14:49 PMI'd take off all the effects, set the input sensitivity to say +5 and the recording level as high as it will go without clipping and see how you go.

Sorry Haylie, but setting input sensitivity to a specific setting without regard for the level of the source is bad advice. There's only one correct way to set input sensitivity. While playing or singing at your highest expected level, you increase the input sensitivity until the PEAK indicator lights occasionally (indicating clipping). Then back off the level slightly so that the PEAK indicator no longer lights. The idea is to have the input level as high as possible without clipping (indicated by the PEAK indicator).

Input sensitivity isn't something that you set once then forget. It must be set correctly before each recording. That's because the input signal changes between recordings. For example, if you record some chords with an electric guitar, then record some bass guitar on a different track, the levels from the electric guitar and the bass will be quite different. So you need to set the input sensitivity accordingly. Even with the same instrument, the input level can be quite different between recordings. For instance, strumming chords on an electric guitar will produce a different level than fingerpicking or a lead solo. So you have to play the way you intend to record and set the input sensitivity according to your loudest playing. It's the same with vocals. Every time you sing, the level is different, so you have to set the input sensitivity each time. If you just use the same setting all the time, you're sure to get either clipping or a poor signal-to-noise ratio and dynamic range.

Quote from: Hilary on April 22, 2013, 12:58:36 PMI don't think you can rely on it, mine rarely comes on but I still get clipping - I check my vox in Audacity and adjust the levels accordingly :)

Clipping can occur at any point where the level can be changed. To avoid clipping, you have to know where those level-change points are, and set each one correctly in the order of the signal flow. The order is critical because once clipping is introduced, it will be present at every subsequent stage. Turning down the level can't remove clipping once it's present. It can only prevent the clipping from happening in the first place.

The signal flow on a BR-80 in MTR mode is like this:



Since it's critical to set the levels in the order of signal flow, the Input Sensitivity is the place to start within the BR-80. Set it as I described above. However, it's important to note that the correct input sensitivity setting depends on the level of the source (guitar, mic, etc.) If you set the input sensitivity perfectly, then go and change the volume, tone, or pickup selection on your guitar, you'll have to go through the input sensitivity setting procedure again because the level from your guitar has changed. It's the same with microphones. If you set the input sensitivity perfectly, then change your distance from the mic or change the loudest of your voice, you'll have to reset the input sensitivity to these new conditions.

Once you've set the input sensitivity correctly, you can set any effects you want to use.

After you've set the effects, you can set the record level according to the IN level meters in the display. There's no peak indicator here, so you want to set the levels as high as possible without lighting the top segment of the meters very often, if at all. In digital recording, clipping is always more objectionable than poor signal-to-noise or dynamic range. So, if you want to play it safe, set the levels so that the top segment of the meters never lights. But don't set it any lower than you have to. If the level's too low, you'll get noisy recordings with little dynamic range. You can boost the level during mastering, but it will boost the noise too, and it won't improve the dynamic range because the lowest levels are boosted just as much as the highest.

Once the recording level is set, don't change anything. If you change anything, you'll have to redo all of the settings after it in the signal flow. For instance, if you set all of your levels perfectly, then decide to switch pickups on your guitar, you'll have to redo the input sensitivity, then the effects, then the record level. If you set all your levels perfectly, then wanted to change effects, you'd just have to redo the recording level. The input sensitivity should still be okay in this case because it comes before the effects in the signal chain, so changing the effects can't affect the input signal but it will affect the record level.

Finally, you can also get clipping during bouncing or mastering. When bouncing or mastering, there is a separate level parameter and meters. The meters include a peak indicator, so set the level so that the "P" never lights.

Also, remember that it's not just the parameters labelled "LEVEL" that can affect signal level. Many other parameters will have an effect on the level too. For example, changing EQ changes the level. So, once your levels are set, it's important not to change anything. Or, if you do, then you need to redo all your levels that come after that point in the signal path.

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Boss BR-864
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"When one person suffers from a delusion it is called insanity. When many people suffer from a delusion it is called religion." - Robert M. Pirsig

Hilary

Quote from: 64Guitars on April 22, 2013, 05:38:39 PM
Quote from: Hilary on April 22, 2013, 12:14:49 PMI'd take off all the effects, set the input sensitivity to say +5 and the recording level as high as it will go without clipping and see how you go.


it was a suggested starting point to experiment with - it's a very personal thing and you need to find your own settings specific to your voice (in this instance as that's what the query was about). I usually have mine set at
-5 and yes, do change it, depending on what I'm singing - but -5 for me is usually a good base at which to start (but I have a very loud voice and capturing it has proved extremely difficult and taken on long time to find out how to do with a Rode mic). As I said, the only real way to sort it out is good, old fashioned trial and error because mics, preamps, voices are all individual and have their own requirements.
recorder
Boss BR-80

comme ci, comme ça

chip

Hi thanks for the help. 64 mentions  segments but the BR80 has none. So am I correct in saying that the input level should not hit the horizontal  line on the BR80' screen? I just find the recording level to low for reference when it doesn't for vocals, the guitar is fine. I am getting closer, the peak doesn't light in either input sens or input level but it does hit the top on vocals only.
Sweet young thing aint sweet no more.

64Guitars

Quote from: chip on April 23, 2013, 03:22:57 AMHi thanks for the help. 64 mentions  segments but the BR80 has none. So am I correct in saying that the input level should not hit the horizontal  line on the BR80' screen?

The BR-80's meters have a higher resolution than the older BRs. But each meter is about 24 pixels high by 5 pixels wide. Each row of pixels is what I mean by a segment. I don't have access to a BR-80 so I don't know if the meters extend all the way up to the line above them. If they do, then you just need to make sure that there's always a gap between the top of the meter and the line.

However, it could be that the meter doesn't extend all the way to the line, in which case there will always be a gap. You can find out by increasing the level so that the meter is displayed at its maximum height. If, for example, you find that there's a 1-pixel gap between the top of the meter and the line, then you'd have to make sure that it never goes beyond 2 pixels below the line, as shown in Track 2 and the left Rhythm channel of the following screenshot.



recorder
Zoom R20
recorder
Boss BR-864
recorder
Ardour
recorder
Audacity
recorder
Bitwig 8-Track
     My Boss BR website


"When one person suffers from a delusion it is called insanity. When many people suffer from a delusion it is called religion." - Robert M. Pirsig

chip

Quote from: 64Guitars on April 23, 2013, 10:40:31 AM
Quote from: chip on April 23, 2013, 03:22:57 AMHi thanks for the help. 64 mentions  segments but the BR80 has none. So am I correct in saying that the input level should not hit the horizontal  line on the BR80' screen?

The BR-80's meters have a higher resolution than the older BRs. But each meter is about 24 pixels high by 5 pixels wide. Each row of pixels is what I mean by a segment. I don't have access to a BR-80 so I don't know if the meters extend all the way up to the line above them. If they do, then you just need to make sure that there's always a gap between the top of the meter and the line.

However, it could be that the meter doesn't extend all the way to the line, in which case there will always be a gap. You can find out by increasing the level so that the meter is displayed at its maximum height. If, for example, you find that there's a 1-pixel gap between the top of the meter and the line, then you'd have to make sure that it never goes beyond 2 pixels below the line, as shown in Track 2 and the left Rhythm channel of the following screenshot.





Hi. I see what you mean. If we look at the input levels far left. When I sing into the mic I keep hitting the horizontal first line, it does not go over the first line as that's as far as it can go. If I shout then a peak warning appears above the first line. I cannot get the signal into the position you show as it is simply not loud enough to be of much use so the meter will always be touching the line but not continuously. It will fluctuate depending on my range and attack

Lets look at the say track 4 on the picture, lets say this is vocals. When I play back the vocal track, the meter will hit the first horizontal line on a more than regular basis. If I sing in a continuous manner, say a long harmony the meter will stay almost glued to the top line.

The MBR seemed better for louder playback and recording. I will have a more in depth look at it all later, if I get time.
Sweet young thing aint sweet no more.

Auroran

Quote from: chip on April 24, 2013, 04:02:28 AMLets look at the say track 4 on the picture, lets say this is vocals. When I play back the vocal track, the meter will hit the first horizontal line on a more than regular basis. If I sing in a continuous manner, say a long harmony the meter will stay almost glued to the top line.




I don't know if the  mbr/BR80 series has a mixer? With the mixer on the BR-800, if the faders are set to unity gain, the meters on individual tracks tend to go about 80-90% to that first line . Some of those tracks are imported into the BR from my DAW, which has more accurate metering. That's plenty loud. In fact, I can't get one to hit the line unless I turn the fader all the way up. If your individual tracks are hovering on that line, I'm guessing that they are recorded too hot (only a guess). Or, your faders/settings whatever might not be correct.

In general, prosumer gear has less-than accurate metering, and the pres don't need to be pushed. In other words, don't lose any sleep over it. ;D  Getting a nice strong signal is important of course, but beyond that it's not going to help you to cram it to the line. Most of my pro engineer buddies don't record all that hot, and scoff at the notion of doing so (snide buggers they are  ;D).

Remember: The "Loudness War" is usually about the mastering process, not tracking or mixing. There are plenty of tricks like compression and limiters to help along the way, but tracking levels don't have to be so high that there's even a remote chance of clipping. The best way to get an individual track loud is to avoid peaks all they way through the process, whether that means a smoother performance, editing, compression/limiting etc.




recorder
Boss BR-800

64Guitars

Quote from: chip on April 24, 2013, 04:02:28 AMLets look at the say track 4 on the picture, lets say this is vocals. When I play back the vocal track, the meter will hit the first horizontal line on a more than regular basis. If I sing in a continuous manner, say a long harmony the meter will stay almost glued to the top line.

If the IN meters do that, then your record level is too high and you'll definitely have clipping. The only way to fix it is to re-record the track at a lower level.

However, if your IN levels were fine (never touching the top line), then it just means that your track levels are too high for mixing. Reduce the level of that track before you bounce or master. See page 63 of the BR-80 manual.

Quote from: chip on April 24, 2013, 04:02:28 AMThe MBR seemed better for louder playback and recording.

Don't confuse recording and mixing levels with monitoring loudness. They're two separate issues. Recording levels must be set for the highest signal level without clipping. When mixing, you set the track levels for relative loudness in the mix, but must also be sure not to get clipping on any track. The monitoring loudness in your headphones is determined by the BR's built-in headphone amp and the Volume control on the left side of the BR. If the monitoring level isn't loud enough for you, don't try to compensate by increasing your recording level or track levels. That will only result in clipping. Instead, consider using a separate amplifier for monitoring. For example, you can connect the BR's Line Out to your home stereo system and plug your headphones into its amplifier instead of the BR. Or, you can purchase a small headphone amplifier like this Behringer HA400, for example:

http://www.dv247.com/studio-equipment/behringer-ha400-microamp-ultra-compact-stereo-headphone-amplifier--33860

recorder
Zoom R20
recorder
Boss BR-864
recorder
Ardour
recorder
Audacity
recorder
Bitwig 8-Track
     My Boss BR website


"When one person suffers from a delusion it is called insanity. When many people suffer from a delusion it is called religion." - Robert M. Pirsig

chip

Thanks for the help there folks. The headphone amp sounds plausible. I found this http://www.amazon.co.uk/FiiO-E06-Portable-Headphone-Amplifier/dp/B005HJWWW8 which looks cool and has only one input instead of four like the behringer. It seems to fit the bill and has great reviews. What do you think?
Sweet young thing aint sweet no more.

64Guitars

Yeah, that should work okay. I watched a YouTube review on it just now and the only thing that might not be too good is that you have to hold the switch for 3 seconds to turn it on or off. That could get annoying.

Another thing to consider is that it runs from an internal rechargeable battery. Depending on the type, it might be hard to find and/or expensive when it comes time to replace it. If that's a concern, you might be better off finding a headphone amp that uses ordinary batteries or a power adapter.

recorder
Zoom R20
recorder
Boss BR-864
recorder
Ardour
recorder
Audacity
recorder
Bitwig 8-Track
     My Boss BR website


"When one person suffers from a delusion it is called insanity. When many people suffer from a delusion it is called religion." - Robert M. Pirsig