Part of the MasterRig plugin in WaveLab is the ability to apply saturation to the lower frequencies. I love this plugin, it sounds amazing, but I don't love WaveLab and would like to do this in Logic. As far as I can tell, the MasterRig plugin is simply not available outside of WaveLab.

I have tried splitting the signal into low and high using busses (and the single band eq plugin). It works, but I'm not 100% sure what the correct settings would be to make sure this doesn't attenuate or amplify any of the frequencies in the crossover region. It's also a little awkward.

For the tape saturation, I'm using Apple's tape delay plugin with 0 delay. Also sounds great.

What's a better way to achieve this (ideally with stock Logic plugins)?

  • Does the crossover region matter that much? Is this for mastering? Apr 4, 2019 at 17:39
  • I guess it doesn't matter that much. Apr 5, 2019 at 8:54

1 Answer 1


Instead of sending it to two different busses, just duplicate the track. Put a high pass filter on one copy, and a low pass filter on the other copy and make sure the cutoff frequencies are the same.

Then just put whatever plugins you want on one track or the other.

This was done quite often in the analog world, where one tape track was multed to two or more channels on the mixing console. Then the same track could have two different mixes that could be switched between (using mutes) or layered on top of each other. The way to do the same thing in the DAW is with track duplication. Note that duplicating a track does not create a separate copy of the media files used by the track, so you're not taking up more hard drive space with this trick.

The reason why making the cutoff frequencies the same ensures no total attenuation or boost at the crossover point is because by definition, the cutoff frequencies are the 3 dB down points. At the exact crossover frequencies, each of the high and low tracks are 3 dB down. When they are combined, they add up to the original power level, because 3 dB down is half the power. The other aspects of the filters you want to match for smoothest crossover is the slopes. Once you pick 6 or 12 or 18 or 24 or whatever dB per octave, make both the highpass and lowpass filters have that slope.

All that said, once you put different plugins on the different high and low tracks, you're going to make them different from each other to the point that having a smooth crossover region is pretty much meaningless. If you tape saturate the lows and not the highs, then you've just changed the the levels and loudness of one while leaving the other the same, which means your crossover region is now a mixture of something different with something the same. There's no preventing that - that's part of what you are deliberately doing to the audio.

Another way to approach the whole thing is to leave the original track as is and then just low pass the duplicate track. Saturate the crap out of the "low" track - way more saturated than you want it to sound - and then turn it all the way down. Now slowly bring it up while playing back until you are adding in the amount of the low saturation that you want. If the whole thing seems like it has too much low end at this point, you can add a low shelf to the original track to drop it down slightly.

No matter what, your whole goal as a mixer is to make it sound good, not to make it sound... anything else. Don't worry about weird things happening in the crossover region. Worry about it sounding bad. If it sounds bad, isolate why and then change it. Maybe it turns out to be the EQ settings, you just have to change them to make them sound better, but there's no one set of EQ settings that someone else can tell you will sound good. You have to figure it out based on the actual musical material you are working with. It's like asking what paint colors to use to paint a flower in a picture. There's no one answer. Your answer is the answer that for you gives you the best representation of the material that you have.

  • The OP is worried about what happens with the crossover region: phasing, attenuation, amplification etc. If you do it manually, you have to solve it yourself, when in an integrated multiband processor it can be assumed that if it's properly made, the processor will keep things nice and tidy, particularly if it's meant for mastering. So how to set the band splitting EQs? Apr 4, 2019 at 17:38
  • @piiperi I'm not sure I understand your question. Are you asking how to set the EQs for the two duplicated tracks or are you asking how to configure the crossover frequencies for integrated multiband processors? In the latter case, of course it depends on the processor. In the former case, you can set them however you want. You don't even have to choose the same corner frequencies, even though I suggested that in my answer. Technical knowledge, experience, and artistic goals will inform the decisions about how to set the EQs. Apr 4, 2019 at 17:52
  • I meant this part of the OP's question: "It works, but I'm not 100% sure what the correct settings would be to make sure this doesn't attenuate or amplify any of the frequencies in the crossover region." Your answer does not address that part, and I don't think it helps to say you can set them however you want. Or that you just have to have technical knowledge, experience and artistic goals. ;) Apr 4, 2019 at 18:04
  • @piiperi I expanded my answer to address that more, but it really is that you can set them however you want. There are no objective answers to artistic decisions, and mixing is at least as much art as it is a science, and even moreso when applying tape saturation plugins to only the low frequencies of a track! Apr 4, 2019 at 18:12
  • 1
    @piiperi - I know this. But the equing method suggested is the same approach as arallel compression. Split it, treat it, and add a bit back in.
    – PeterJ
    Apr 5, 2019 at 10:57

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.