ChrisPFuchs
New member
Hi, I have a few questions regarding basic gain staging of my setup.
First, I have my microphone plugged into a Mackie ProFX8 mixer. After the mixer, it is getting sent out the main outputs into the corresponding line inputs on a LineSix Ux1, which is acting as my recording interface. It is set to record at 16bit/48kHz. This is plugged into my computer via USB, and I'm recording using ProTools 11.
There is a light on my mixer that lights up to help notify you to when you have a good level set for the gain nob. There is a second light that lights up to signify clipping. Generally, I set gain and keep the fader at unity. I also am keeping the main faders at unity. The level of which my preamp is set should then be getting sent out of the main outs at the same level.
I notice the light that signifies I have a good level set flashes exactly at 0dB on my Main Meters on the mixer. These meters are labled 0dB = 0dBu. 0 dB is in the middle of these meters with OL being more than 15dB above that. If the signal is steady around 0dB on the mixer, with the amount of headroom, usually there is plenty enough headroom for the transients. At this point, everything seems normal and how it should be.
Now, what I don't understand is as it gets recorded into Protools, a signal playing (I tested this with a 500 Hz sine wave) at exactly 0dB on my mixer is being recorded at -5dB in Protools. I understand that Protools has a different measurement for their meters. Since it's digital, Protools has it's meters in dBFS, so 0 is the point of clipping. The dynamic range between -5 dBFS and 0dBFS is tiny compared to the 0dB and +15dB of headroom on my mixer.
-Why is it that Protools will clip way before my mixer would ever overload?
-If I recorded at a 24bit rate, would the headroom in Protools raise so that the 0dB signal on my mixer equals to less than the -5dBFS with me recording in 16bit?
I've been taught to record into Protools at roughly -18 dB. This gives plenty of headroom. If I were to set the level of my Sinewave to record at -18dB in Protools, I dramatically have to turn down the gain or the fader in order to lower it to that level. The equivalent on the mixer shows that at around -20dB is equal to -18dBFS on the Protools meters.
-When it does clip in Protools when recording (but not overloading on mixer), it totally flattens the waveform as expected, but it doesn't actually sound distorted, more like very compressed? Why is this? Why doesn't it have a nasty distorted sound? Does anyone know what's causing this, or at what point the signal is getting clipped? Is it at the converters? I don't have a limiter or anything like that in my signal chain.
-To record at an acceptable level in Protools, I need to lower the levels on my mixer a lot. Should I lower the gain control on my mixer or the fader? I see two possible ways of thinking. One is that I could set the gain to hit 0dB on the mixer like normal, but then lower the fader a lot until it reads around -18dB in Protools. The other way of thinking is to lower the gain, because as I boost the gain, it introduces extra noise, and since I don't need the volume, might as well keep the noise out and the volume lower.
I just don't want to be missing something important, or have my gain set too low in order to record at a proper level in Protools.
If anyone can clear up some confusion, I'd really appreciate it, and thanks for taking the time to read my post.
-Chris F
First, I have my microphone plugged into a Mackie ProFX8 mixer. After the mixer, it is getting sent out the main outputs into the corresponding line inputs on a LineSix Ux1, which is acting as my recording interface. It is set to record at 16bit/48kHz. This is plugged into my computer via USB, and I'm recording using ProTools 11.
There is a light on my mixer that lights up to help notify you to when you have a good level set for the gain nob. There is a second light that lights up to signify clipping. Generally, I set gain and keep the fader at unity. I also am keeping the main faders at unity. The level of which my preamp is set should then be getting sent out of the main outs at the same level.
I notice the light that signifies I have a good level set flashes exactly at 0dB on my Main Meters on the mixer. These meters are labled 0dB = 0dBu. 0 dB is in the middle of these meters with OL being more than 15dB above that. If the signal is steady around 0dB on the mixer, with the amount of headroom, usually there is plenty enough headroom for the transients. At this point, everything seems normal and how it should be.
Now, what I don't understand is as it gets recorded into Protools, a signal playing (I tested this with a 500 Hz sine wave) at exactly 0dB on my mixer is being recorded at -5dB in Protools. I understand that Protools has a different measurement for their meters. Since it's digital, Protools has it's meters in dBFS, so 0 is the point of clipping. The dynamic range between -5 dBFS and 0dBFS is tiny compared to the 0dB and +15dB of headroom on my mixer.
-Why is it that Protools will clip way before my mixer would ever overload?
-If I recorded at a 24bit rate, would the headroom in Protools raise so that the 0dB signal on my mixer equals to less than the -5dBFS with me recording in 16bit?
I've been taught to record into Protools at roughly -18 dB. This gives plenty of headroom. If I were to set the level of my Sinewave to record at -18dB in Protools, I dramatically have to turn down the gain or the fader in order to lower it to that level. The equivalent on the mixer shows that at around -20dB is equal to -18dBFS on the Protools meters.
-When it does clip in Protools when recording (but not overloading on mixer), it totally flattens the waveform as expected, but it doesn't actually sound distorted, more like very compressed? Why is this? Why doesn't it have a nasty distorted sound? Does anyone know what's causing this, or at what point the signal is getting clipped? Is it at the converters? I don't have a limiter or anything like that in my signal chain.
-To record at an acceptable level in Protools, I need to lower the levels on my mixer a lot. Should I lower the gain control on my mixer or the fader? I see two possible ways of thinking. One is that I could set the gain to hit 0dB on the mixer like normal, but then lower the fader a lot until it reads around -18dB in Protools. The other way of thinking is to lower the gain, because as I boost the gain, it introduces extra noise, and since I don't need the volume, might as well keep the noise out and the volume lower.
I just don't want to be missing something important, or have my gain set too low in order to record at a proper level in Protools.
If anyone can clear up some confusion, I'd really appreciate it, and thanks for taking the time to read my post.
-Chris F