Friday, December 30, 2011

New Ears Eve

Alright folks - time to learn something about your ears and analog stuff.

In a previous blog post I talked about loudness and how our ears perceive loudness from primarily average levels rather than peak levels. It's pretty interesting how that happens. We hear a certain frequency balance, a certain punch, a certain width (hmm...all words we use when describing analog gear) and it sounds LOUDER to us. More ALIVE.

Part of this is because of a little thing called saturation. Sure, compression helps aide in the squashing of dynamic range in order to bring up RMS level. You compress something 4dB and then bring up the makeup gain 4dB, the "apparent loudness" of the track easily went up 4dB because your peaks stayed the same (thanks to the makeup gain) but your average went up. But what about those times we DON'T want to use a compressor? When it sounds too obvious? When it pumps? What then!??!

Analog desks have multiple benefits. One of which is saturation. Another of which is routing possibilities. Another still is analog summing. A Big trend these days is to use analog summing mixers like the Dangerous 2Bus. This product allows mixers to send out of their DAW into an analog box that sums using components, all analog, like an analog console does. However, these boxes are usually 16 channels. An analog console is usually much larger. 24, 48, 64, 96 input boards are common. This means that you have to do digital summing in the box to get the mix down to 8 stereo groups (i.e., 16 mono outs) anyway. On a real analog console, it's easily one track per fader.

So what makes analog summing better? I used to think it was some mythical thing about width and depth and blah blah. What I've learned (at least what I THINK is happening) is the subtle saturation characteristics from each channel adds what I call a "tightening and heightening" effect. It tightens up the low end thanks to its saturation (i.e., saturation from transformers / circuitry) and it sort of livens it up due to the harmonic content added by the saturation circuitry. It's subtle. You may not notice it on a track by track basis. However, when added up together, it's sort of like the Lombard effect - people in the pub talk louder and louder as they slowly can't hear themselves over each other, and soon enough the loudness of the room is extremely obvious. Little bits add up quick.

To prove my point, take a listen to these two drum clips.

DRUM CLIP A:
http://www.theclosetstudios.com/Drumtest-A.wav

DRUM CLIP B:
http://www.thecloststudios.com/Drumtest-B.wav

Which one of these sounds more like the "analog characteristics" we talked about? More punch, apparent loudness, and width?

If you put them side by side in a DAW and play them, you will notice a few things. First, Clip A sounds a bit louder, wider, and has more depth. Listen to the room sound on clip A - it's more apparent! You hear more of the snare in the room. Now look at the meters - Clip A is 4dB QUIETER than clip B. On my meters, Clip A is -9.4 dBFS and Clip B is -6.0 dBFS.

Why does Clip A sound bigger, wider, and deeper, but it's over 3dB quieter?

Answer: ANALOG SATURATION.

Clip B was the original drum bus render. I ran it through some analog preamps and drove the transformers fairly hot. No EQ or compression, just natural saturation from analog preamps. This decreases the peaks, bringing up the harmonics and saturation, and allows for the natural compression (without pumping) to take place. This in turn yields a fuller, more balanced drum sound.

So, then after you do that, turn up Clip A 3.4dB to match the peak levels of clip B. Now guess which one is still louder? Haha...much more obvious that time.

Crest Factor is a term that means "the different between the highest peak level and the RMS level." So if your mix peaks at -1.0dB and your RMS level is -11dB, you have a crest factor of 10. Most modern standards suggest that anything more than 20dB is a super dynamic mix. Many modern rock mixes have crest factors of around 5-8dB. It is very likely that if you did a mix on an analog console and tracked to tape, your mix (DRY) would have a natural crest factor of maybe 10-12dB BEFORE compression, and a digital one may have 20+dB before compression. It is in this way that digital mixers often have to add more compression than analog mixers to compensate for this.

The solution: If you're wanting the Analog sound (like many of us are), use a healthy balance of saturation and compression. If you only use saturation, your mix will likely be out of control and probably gritty and overdriven. If you use only compression, your mix may have no edge, and instead pump and breathe in weird ways - it will sound smaller and wimpy rather than in your face.

Find a balance between saturation and compression and you will surely improve your mixes.


So the verdict on analog's depth? I don't think it's some magical "stereo widening" effect or some crazy "depth creator" even though we use the terms like "more width" and "more depth" from analog. Why is that though? I truly believe it's because of the aforementioned "tightening and heightening" effect of analog. Single tracks, entire mixes, it was obvious in the drum clip I send you above.

Another thing to think about - these days we are often using smaller rooms for recording (as many large studios have gone out) and then having to create ambience later. By running through analog gear post mix and driving it, we are essentially compressing it via saturation. When you compress something with ambience, the ambience is brought up. Note the drum example! Those were done in a big room with lots of compressed room mics. When you run it through analog, the room sound gets compressed too, making it much more obvious. This I believe is what makes a lot of "analog" mixes better. We used to record more room mics, more "real space" and now we don't, we use it on FX sends.

Another one of my solutions for this? Don't do aux sends for your room sounds. Plates, chambers, delays, sure --those have very often been aux sends. But for room sound - if you want the recording to sound REAL like it was REAL ambience recorded on those drum tracks, put the reverb ON THE TRACK. Come on, your computer is powerful enough to do that. That way when you compress them, it will react like it really would have in the analog days. Real room sound to a compressor. Sending a compressed drumkit to a room is nowhere close to compressing a big drum room stereo pair and blending it in. TRY IT.

In my opinion, the inserted reverb sounds more ALIVE. More REAL. I've been working on a book / DVD about recording and mixing for ITB and this is one of the biggest chapters in there - understanding ambience! It's not just "reverb," it's supposed to be PART of the sound. Sending the mics to an aux does very little for us. It doesn't make the room part of the recording. It makes it an effect. It doesn't make the sound quality of a space apart of what affects our EQ and compression decisions, which I 100% believe it SHOULD.

Doing it this way also allows you to be more tactile with mix. You need more verb? Turn up the ROOM MICS. Not "reach for an aux." It's more natural. Easier to remember, also.



Take these things into consideration, and have a safe new year.

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