I've been diving deep into studying reverb, and while I've managed to grasp several aspects of the concept, there's one that still leaves me a bit confused or isn't entirely clear: the early reflections.

I've come across tutorials where engineers like CLA and others apply 3 or even 4 types of reverb on a single source in a mix to add that 3D depth sensation. For instance, they use a slap delay and room reverb for the "early reflections," a Plate Reverb to add depth, and a Hall to introduce "height" to the elements. Of course, these types of reverb can vary depending on the genre and context. I've tried following a similar method, EQing each reverb to deepen the mix, but I'm still a bit puzzled by the early reflections part.

As I understand it, early reflections are the first sound bounces that reach our ears after bouncing off the closest surfaces, and they inform our brains about the size of a room. So, if I want to simulate a fairly large room, should those early reflections be more noticeable in the mix? I've noticed that many engineers set up this room reverb or slap delay in a way that it's more felt than heard. But if the space I want to emulate is large, should those initial reflections be more extensive and audible? Should some pre-delay be added to these early reflections? Honestly, this topic confuses me a bit, and I'd appreciate additional advice and explanations on this parameter.

 

If the space is very large, then in theory the reflections would take more time to reach you, so adding extra predelay would make the situation more realistic. But whether this kind of "realism" is going to be useful in a track or not is a whole other question.

Reflections "inside" the sound inform a human very viscerally about a lot more than just the normally taught "room size" parameter. They will inevitably have an effect on the timbre because they end up inside of every sound, and they affect emotional vibe and feel, which is why you see those famous mix engineers piling on different reverbs and delays like madmen, seemingly without logic or reason. It's got a reason and method to it, it's just not the "realism" factor they're after. They're using the different reverbs like chefs use spices to get a certain feel and vibe that they already know that reverb box is capable of adding.

You can do the exact same thing in your mixes, just play a lot with the reverbs and delays you like to get to know what feel and vibe you can get out of each of them, rather than thinking "I need more realism in this", be more like "I need more of that one cozy vibe I heard the other day from the delay box, that one which sucks on everything but is somehow magical on snare..."

 

Last edited: Feb 8, 2024

Find a simple, known reverb plugin that has a separate section of the ER and Late Reflection. Try to mute one or the other and test it with percussive elements. You can learn a lot about how the structure of reverb is designed by combining those two. Examine every factory preset. The preset name should give you a hint about the size and the character of the reverb. Mute the Tail, listen to the ER. Next mute the ER and only listen to the Tail only, figure out what is lost and how loud the ERs are. From that you can get a good estimation about their levels. The answer to your question is on those "Hall" "Large Room" "Tunnel" all sort of big space presets. Learn to understand how each reverb algo in one plugin differs from one another, an ER tactic used on say "Room" algo isn't necessarily the same for "Hall" algo. Then move on to another plugin. By doing it continuously you will sense a pattern in them and slowly develop a way to look at it correctly.

You'll also learn that every single reverb plugin (algorithm) is different for the way how they are coded/designed so there's no definite answer for it. Saying a certain predelay should work for the ER is simplifying it too much and can be misguiding, ultimately could affect you in a long run. The worst being, working in music production for 5 years but can't tell a good quality reverb vs bad algo reverb accurately.

One philosophy could work with one algo and wont for the other. Certain reverb algo define the reflection differently, such as the famous Quantec Room Simulator being one that you should study for its unique idea, apart from the usual Lexicon, Bricasti, EMT250 all those famous reverb designer. Most of the reverb plugins these days are rooted back to those legendary ones mentioned (and more, find it). So how one'd normally think of the levels, type of ER won't work on every reverb for how the whole reverb itself is designed and inspired from. Then there's diffusion topic, then modulation. It affects both ER and LR character differently. Some ER needs it to sound realistic, some will destroy the effectiveness of the ER.

Although ER is understood as the "First reflection" there is still layers in it. The very first reflection (of the first reflection, lol) is called "Principle Reflection" followed by "Ray Depth" which what happens next and how much it repeats. The idea being, things reflecting fairly quickly on small space, differently if the room is not perfect square, asymmetrical surfaces has different behavior, stuff like that. The types of ER also crucial to determine the right settings for it whether it's a Burst of Diffused Delays kind of ER. For a large space sometimes it's not the overall levels that matter, it could be how the ER simulate distance attenuation realistically. It's a rabbit hole.

Slap Delays, Ambience type of reverb are mostly used for give or take the same reason of why people use ER but they act more like FX than to simulate real spaces. However a smart/creative/experienced engineer knows how to make it sounds real with added characters of those FX. Gotta understand what is "real" first.

The most important thing is don't expect to even understand it in a day, or a week, or a month. Slowly, because you ears need time to learn too. It's not all theory. The understanding will develop slowly with your ability to focus listen them. You don't get to automatically able to listen to things happening in miliseconds of time just like that. Assuming you aren't born gifted with special power. It needs training and dedication. Understanding only the theory wont get you far if you dont know what to listen to. What you think is right today, wont feel right the next two weeks if you keep studying them, when you start to feel that, it means your ability is developing correctly. No known shortcut for it.

Apologies, I just typed without thinking, pretty sure a 5yo cant understand any of this.

 

I think you have a good understanding already. But early reflections would only provide "depth perception" to the closest reflective objects/surfaces in the space. It helps to add a front layer of depth, but can't be indicative of the size of the space. You could put a plate 2 feet in front of you, in a 200 foot long hall. The early reflections are not an indicator of the room size.

If you look into reverb and delay vs human hearing and depth perception, it's a generally accepted "fact" that most of us can discern 2 to 3 different static layers of depth consistently. It's just a rule of thumb, really. You can use pre-delay and early reflections to either add more texture to that, or even as one of your 3 layers.

But it is all just background information anyway, that you can keep in mind when building a template or things like that. I have never loaded up any reverb in a DAW project that did not need some listening to and tweaking.

 

Reverb really isn't that difficult a concept to understand cos everyone deals with it on a daily basis, and yes, that includes deaf people.

Reverb is largely about the science of how sound reflects off the various surface that exist in life and then reverberate, or bounce, around.

For people who can hear, this affects how you hear sound as the reverberation off various surfaces is naturally mixed in with the sound source. This is something humans are tuned into and instinctively understand and what ultimately translated into our spatial awareness, i.e. makes us able to understand and comprehend the space the sound if happening in and where the sound is coming from. It even applied to deaf people, particularly in the lower frequencies that carry heavier vibrations that can be felt; just think of how you feel the bass vibrating through your chest next time you're in a club or at a festival.

Using reverb in a track is simply trying to emulate and create this sense of familiar space for a listener so that the song instinctively makes sense to them and can be easily listened to.

Early reflections are a part of this. As a simple example, if you sit at your studio desk listening to sound from your speakers, the sound will reverberate, i.e. reflect, earlier off surfaces nearer to the speaker. So, you will have earlier reflections happening off the desk for example than you would off the back wall of the studio.

Therefore, think of these mixtures of multiple distanced reverb on a single sound source as just more comprehensively creating that sense of space with stuff in it, having multiple reverbs catering for the reverberation off different surfaces at close, mid, or far distances from the sound source, closer objects being the early reflections.

Or at least this is how I look at and understand reverb, without going into the science of sound waves, standing waves, wave lengths and frequencies and so on to give a more mathematical response.

 

It can be a confusing concept, so fair enough if it confuses you!

Look for the Mixing With Mike YouTube channel and search things like "early reflections" and "space" and "depth" within his channel's search field. You'll find probably 5 or 6 videos of his that have explained the topic. To me, his videos on early reflections set the best foundations for my understanding on the concept. So rather than me regurgitate his knowledge, I'll just recommend his vids. After you watch those you'll have all the fundamentals you need. From there your extra knowledge will come from experimentation.

Matthew Weiss also has a few good vids on the topic too.

To me this is one of the biggest keys of great mixes. But understanding how the parameters affect the space is something that's hard to gain from videos. It really must come from experimentation to get a good feel for it.

That said, if anybody knows great vids on this topic (from actual pros, not uni students masquerading as pros on YouTube) please link me! I'm always keen to pickup more tidbits of perspective on it, it's a fascinating concept and really satisfying when you get it to sit right

 

Do you have links to these tutorials referencing 4 or 5 reverbs on a single source? I'm always interested in how people use reverb and want to hear the results? I've encountered 2 being blended before and that makes sense. I've also seen producers subtly using just one per element to create beautifully spacious mixes. And almost no reverb in epic atmos film score mixes.

 

this is a good question.

as others have pointed out already, the "first reflection" of a sound event (which we should not put in quotes, because they are just that) is the by far most important element how the brain recognizes or associates the position of the sound event - and/or the room.

so you can indeed use first reflections (for example by using reflections-only in a reverb preset) as amixing tool similar to how you use parametric EQs or the panning and gain staging.

you would typically "build" a consistent room by using settings which are releated to each other, and to the pan position of the source signal.

but then there are similar techniques, which do not utilize reflections but work with haas delays between L and R or combinations of both, which are also used to mix tracks.

reflection == continous echo of the sound event including air damping and "wall" damping (i.e. frequency filtered)

they exist in real life everywhere (just as the L vsR delay mentioned above) and so you can recreate that phenomen to mix audio.

try walking through your house in complete darkness while covering your ears... or compare your studio with or without wall damping...