Sample Aid
  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Logic 8 Independent Monitoring Level feature

Discussion in 'Logic 8' started by pfloyd714714, Jul 14, 2010.

  1. pfloyd714714

    pfloyd714714 Senior member

    I have this box checked in the Audio Preferences, but moving the record-enabled channel strip's fader has no effect on the volume through my headphones. All faders control volume levels work as expected during playback. Can anyone tell me why? Additional info: I have my audio interface's outs going into a Mackie Big Knob. My headphone and monitor levels are controlled there.

    Thanks for any help,

    Jim

    iMac quad-core i7, Logic 8.02
     
  2.  
  3. Peter Ostry

    Peter Ostry Administrator Staff Member

    Are you sure that you monitor the recording signal through Logic? I had a Big Knob for a short while but do not remember all functions. Maybe you monitor the incoming signal through this controller or you use direct monitoring in your audio interface. With direct monitoring and "Software Monitoring" turned off in Logic the volume fader has no effect because this is not the signal you hear.

    Btw, if you can, it is better not to monitor through the computer. Less latency.
     
  4. pfloyd714714

    pfloyd714714 Senior member

    Thanks for the remarkably quick reply, Peter.

    I've always avoided the "Software Monitoring" option because I understood that it imparts all the latency created by any instantiated plugins, thereby making recording difficult. (When tracking, I have some plugins on audio channel strips, but never on the Output strip.) Is this how you record? Or are there still more Logic basics that I don't understand?

    Thanks again,

    Jim
     
  5. Peter Ostry

    Peter Ostry Administrator Staff Member

    No, I work with external preamps, split the signals before the interface and use a mixer and a controller for monitoring. Not the easiest way but latency-free and allows to deliver a good monitoring sound via EQ, Compressor and reverb which are built into the mixer.
     
  6. pfloyd714714

    pfloyd714714 Senior member

    OK--I can see how your method works. But is this what's required for the "Independent Monitoring Level" function to work?
     
  7. pfloyd714714

    pfloyd714714 Senior member

    Peter

    Further to your 12:00 post...

    I, too, use external preamps. So can you answer these questions.

    First, how do you "split the signal" coming out of the preamp. Do you simply use a y-xlr cable (if there is such a thing) or is something more complex needed to maintain signal integrity?

    Secondly, as you're recording into the preamp, the backing tracks are being played through Logic, right? Aren't those effected by latency? In other words, I see how monitoring the signal you're recording through a mixer = zero latency, but what of the sounds that you're listening to, which are already tracks in Logic?

    I'm an amateur (can't you tell?!?) who records for fun, not profit--so sorry if the questions are on the daft side.

    Jim
     
  8. Peter Ostry

    Peter Ostry Administrator Staff Member

    No it just means that if you monitor outside of the computer, it makes no sense to wiggle with the fader in Logic. It's not this signal you are hearing. If you want to use Logic for monitoring, you have to turn on Software Monitoring there. Then the fader would work.
     
  9. Peter Ostry

    Peter Ostry Administrator Staff Member

    Nothing complex, there are several ways to do this. First the electrical part: Your preamp may have an output impedance of 80 Ohm. Your interface-, controller- or mixer inputs may have 10 kOhm. If you connect the output to two inputs, your preamp output sees still 5 kOhm and will be happy with that.

    After the preamps you get a healthy line signal, preferably balanced, not easy to disturb. The impedances are ok, therefore you can safely distribute one output to two inputs without degrading the quality.

    You can make your own cables or use a standard half-normalled patch panel or solder custom connectors. It does not matter as long as you connect one output to two or maybe three inputs. Don't try this in the other direction! Never connect several outputs to one input because this may destroy the output stages of your equipment.

    Another method are split boxes, they are used to split microphone lines before the preamps. They work similar to passive DI-boxes but overall balanced. They have one input and two or more outputs per module. The input goes straight through, parallel outputs go through transformers which isolate the original signal from the clones. A solid solution but needs a lot of space and is not necessary to clone a line signal.

    The third and widely used method is to split electronically. Many audio interfaces can do this and the manufacturers call it "direct monitoring". The name is often misleading. If the analog signal gets converted to digital, then splitted and routed to an output where another A/D conversion happens, the signal flow is by no means "direct". There is the latency of two A/D conversions. It can be very short and many people live with it. It is not a good solution if you want to monitor many signals because you would use all of your interface outputs. If you have an interface with an ADAT output, you can use an ADAT converter for monitoring. However, in my opinion splitting before the interface is the way to go if your want zero latency.


    Yes they are but it does not matter. That's the magic of delay compensation in a DAW. Logic measures all plugins and calculates the maximum delay time. Let us look at an unrealistic extreme situation: Due to a special plugin, your playback latency is 20 minutes. Means, when you press the play button, you have to wait 20 minutes to hear the first tone. What are the musicians doing during this time? They drink a beer or two because they hear nothing and cannot play. Then the music comes and they play along. Finally Logic says, "What was the latency? Ah, it was 20 minutes. So I put the files 20 minutes before they were recorded and everything is fine."

    Got it? As long as your interface latency is correctly set, which is really important, you wont have a problem. You play along the playback and Logic knows where to place the recorded parts.

    To check and adjust the latency compensation of your audio interface you can follow John Pitcairn's instructions on his web page:
    http://www.opuslocus.com/logic/record_offset.php
    It is an old article but still valid.


    Me too, most of the time.
     
  10. pfloyd714714

    pfloyd714714 Senior member

    Thanks again for the reply, Peter. You suggest that one can either split the mic signal before or after the preamp. Do you have a preference? There are certainly more commercial options for mic splitters than line level splitters. Are there any specs to avoid?

    Jim
     
  11. Peter Ostry

    Peter Ostry Administrator Staff Member

    I prefer after the preamps because it is technically easier and I don't need additional preamps for monitoring.

    It depends on your setup. If it doesn't change, splitting line signals is good. For more flexibility splitting mic signals is good. Take a piece of paper and draw a couple of configurations. Decide for one with the best routing and optimal cabling. Then think about the technical way of splitting.

    The planning process is more work than one might think. I need at least one or two days, even for small setups. The most time consuming part is to collect detailed information about all circumstances and the kind of usage. And I mean really everything because forgetting about one single fact may render the best plan useless.

    For line splitting you should avoid active mic splitters where the manufacturer definitely says that they are built for mics. At least ask about that detail. Simple passive mic splitters work for line signals too, each module has a direct path for recording and one or more 1:1 transformers for the cloned signals.

    For simple line splitting where you split one line signal into two, you can use a half-normalled patch panel. If TRS plugs and jacks are not solid enough for you, you can use a TT panel. If you want XLR, I think there is at least one simple line splitter available, without transformers. Or take one or two rack panels with holes for Neutrik jacks and solder your own splitter. Or, if you use multipin connectors, you may be able to solder your splits right there if there is enough space per contact. You can also split by custom made Y-cables but I don't like this very much. I prefer "hard" split points and single cables or multicore.
     

Share This Page