Reverb and space in IDM

[Afro88]

I'm currently searching around for some information regarding reverb and the way it creates space in a mix.

If anyone has any links to detailed guides on how to use reverb I would be grateful. I know how reverb works, I know what each control does and how it affects the sound, but I don't know how to use it effectively. It's like knowing what each function on an EQ does, and how it affects the sound, but not being able to actually use it to any useable degree. [I even built a reverb patch from scratch for the Modular G2 - I understand how a basic reverb unit works, just not how to use it effectively in a mix]

I don't want to know stuff like "use a small room on drums" and "use a large room with massive decay for pads and atmospheres". I've read a million and one web pages and magazine articles telling me what kind of reverb to use for what sound. I understand this, and it's satisfactory, but I'd really like to delve further into much more creative reverb uses and more the theory behind why a certain type of reverb makes an instrument sound one way or the other.

Also what I'm interested in reading is any information on more advanced psychoacoustical uses for reverb/delay. For example, creating the illusion of an instrument being right in front of you, or separating two instruments in a mix with reverb.

If anyone has any information/links to information regarding any of this, I would be very grateful. Thanks

[Kassen]

Excelent question.

There are couple of basics you need to mind; the rest mostly follows from those, at least from a physics perspective; composition is a different matter....

First of all air and walls act as very subtile and smooth lowpass filters. Second; the distance between you and a sound determines the ratio between the sound and the reverb. Very close relatively loud sounds sounds may not need reverb for small spaces as the sound will block out it´s own reverb due to temporal and frequency masking (nearfield monitors depend on this).

Delay will make a sound sound louder, the cleaner and longer the delay the more prominent the effect. This is because only very loud sounds bounce off a distant wall and come back sounding more or less the same in real life. This includes early reflections to some degree, especially if they are spaced far apart.

It´s often wise to imagine what sort of room your track is supposed to be hapening it. A intimate Jazz club filled to the brim with people and with smokey damp air will only have a subtile reverb with hardly any decay because the people and the air will quickly damp it. The soundcheck of a illegal warehouse rave with it´s volume and large amount of reflection from the flat and smooth walls will be a different matter (often the recordings played there will actively embrace this as a aesthetic too!). A group of canibals with bone woodblocks on the edge of a forest on the border of a cave will have a particular reverb indeed. I myself will often start a track by imagining the space it´s set in which will then guide my use of reverb (and often choice of instruments too).

When setting up your soundstage in your mix it often pays off to take such things into account. It´s established dogma that it´s best to use only one reverb per mixdown because presumably all the sounds in the mix would share the same space. That´s fine but comercial reverbs tend to come with only one input which (theorettically) results in all the sounds coming from the same spatial source as far as the reverb is concerned. That´s not too good from a psychoacoustical point of view even if it works for many aplications. Some tactical use of convolution might help if you have access to ways of amking impulses and access to a suitable space (and are willing to talk to the police about firering alarm pistols :¬) ). There are programs to make synthetic convolution umpulses that let you set both the place of the sound and the place of the listener; you could render one per track (or multiple if the track is supposed to "move around".

One option you could considder is using a software reverb that offers seperate settings for early reflections and the general tail. You could set up the early reflections (preferably with eq) for each track depending on such things as distance, l-r pan and volume using multiple copies, then use another copy for the general reverb trail. The muffled reverb trail of a distant large drum would perhaps be all we´d hear of it while a sensitive acoutstic guitar right in front of us´s reverb would only be noticable for loud notes during otherwise minimal pasages.

This is how I might tacle a atmospheric piece; for IDM it becomes both harder and more easy because IDM generally isn´t too concerned with realism and you might want to dramatically move sounds around the sound stage. Reverbs generally don´t take too kindly to being modulated while running. Dopler effect should also be considdered. C-sound has a 2d pan that will take care of volume and dopler for you, you might want to check that out and combine it with a reverb....

Often a couple of clues will already help establish things like the location of your piece, the placement of sound sources and their possible movement. Perfect realism is far, far harder and I´d wonder how badly you need it and how important it is compared to musical expression.

And listen in real life. Notice how walking on one side of the street, close to the wall will make the reverb asymetrical. Notice how having your back to a brick wall will affect sounds. Having your back to a brick wall will often place a wholy different emphasis on scary sounding sounds in front of you. You can use such effects.

Last weekend I was lucky enough to visit the Aya Sophia moske/church in Istanbul. If you ever can; visit it too. There´s a constant smooth noise coming from the (insanely high!) ceiling that blends all the sounds that happend in the building for the last couple of minutes. Yeah, your Lexicaon can do that more or less, but now walk around there and notice how it gets filtered and warped depending on where you are standing. Local churches might let you visit. Warehouses can be goten into by inocently "takinga a wrong turn". Did you ever jump into a concrete alleyway wearing army boots? Try it; it´s good.

Listen, learn and abuse.

[elektro80]

I know nothing about IDM, but a lot of what I have heard here that you guys are calling IDM is pretty damned great. Is it OK if don´t focus on IDM?

A great convolution reverb is Altiverb. http://www.audioease.com/Pages/Altiverb/AltiverbMain.html

You can make your own "impulse" files and you can make extremely weird sounds just by imaking intentionaly nonsensical impulse files. Outdoor spaces, caves.. stuff like that is also pretty interesting to explore.

The Clavia NM-1 and the G-2 are great modular synths but it is not easy to manage to set up patches like you would on analog modulars in the sense that you can use outboard like reverbs and stuff inside patches.

I am using this technique pretty much all the time one way or the other. I very often throw a vocoder or two into patches too.

[Afro88]

Thanks very much for the info Kassen! There's some really great stuff in there. I guess I'm not looking at reverb from the right perspective. See I'd normally set up a room I like, and go through each melody/fx track and slowly send more until I like where it sits, then do the same for drums, chords and bass, sometimes with different rooms. But this ends up with a very boring two dimentional mix.

After reading your post I'm liking the idea of trying to realistically recreate a kind of atmosphere, instead of relying on what someone has told you (small room for drums etc.). Really thinking about where in a room/space you want a sound to come from, where the listener for that sound is etc. It's certainly going to open my ears up to acoustic spaces in the future! I'm into creating more unique spaces, and I think if I approach this based on how it could exist in the real world, I will find it much easier to make it happen in the digital world.

Also, thanks Elektro for the link to Altiverb, but unfortunately I use a PC I'll definitely check out some IR reverbs though, sounds interesting. I always avoided them because I hadn't yet mastered the art of using traditional reverb, but I like the idea of creating your own response files. Vocoded reverb? Sounds like something I should really try out too!

[elektro80]

i have 2-3 songs here somewhere that all use extensively various of my "silly" patches. I should add that compressors are in there too. The main point is to create patches that will move in space, and contain a bit of spatiality withouut being wet the traditional way. You kind of get the spacy feel in a playable patch.. instead of actually getting a recognizable reverb feel to it.

[ian-s]

Interesting topic, especially as I work with entirely synthetic environments. I can only contribute one small tip to do with spatial location. The brain works out the direction of a sound (very quickly, it’s an evolutionary thing) by the relative volume in each ear and perhaps more importantly, the time it arrives. So in addition to panning, try small delays in one channel. Also I’m told that experimenting with subtle channel specific filtering, comb or low pass might be effective. Simulating the effects introduced by the head and ears. This type of thing is most noticeable in headphone mixes but might be helpful.

[elektro80]

[Kassen]

[Afro88]

[Kassen]

One thing I can realy recomend is that whenever you are wondering about how to use certain musical tools is trying to build one of them yourself from smaler building blocks. A envelope follower, a vca and some logic will get you a compressor, a few filters and a couple of mixers with some asorted bits gets you a eq. Noise gates are a nice simple place to start and have lots of room for quirky extra features.

This will get you a much deeper understanding of how the tool is related to what it´s supposed to do, what problems can arise from it and how the parameters relate to the effects. I gained much of my own insights on reverb from trying to build one, even if the end result wasn´t too good.

You´ll also get a oportunity to improve on the things, for example to build reverbs with more then one "location" to choose from with the inputs.

Obviously the G2 or the NM are excelent tools for such experiments.

[paul e.]

my 1.8 cents worth is that reverbs are gimmicky sounding... useful i guess if you are trying to convince a listener you really are in some kind of acoustic space..but i don;t think this is convincing to most ears..

best way to get reverb is to record in a reverberant space..if your sounds are 'throught the wires' only, using a reverb is pretty dubious and will often sound like 'that plug in'

i'm skeptical about fake reverb...today's reverb will sound pretty lame compared to tonmorrow's... just like yesterday's synthesized strings sound really silly today

you may as well play 'sax' on your sampler and ask people to abandon their john coltrane records

[mosc]

[Kassen]

Mosc, for conventional reverb use I can agree with you but I think that your statements here are too generalised. Spatialisation is a way of relating sounds to eachother, to the environment and to the listener. Just like the majority of the synth sounds is utterly unlistenable so is the majority of the attempts at spatialisation. We´re not writing off the use of synthetic sound because of bad euro rave and new age music and so I don´t think we should write off spatilisation because of all the bad examples.

Give some of my ideas above a go, considder the use of spring reverbs or grain based ones, then get back to me. Reverbration is a complex matter, you can´t expect off the shelf comercial solutions to work for your individual style. Just like with synthesis you need to know what you want, then plan out how to get there. This may need work, thought and render-time but proper, tastefull use is never a gimmick.

[Mohoyoho]

I like reverb.

Ofcourse it all depends on the track. Surf music wouldn't be surf music with out the splattering spring reverb.

I like space music, and I think it needs reverb to help create vastness and distance. In the mix some tracks need more reverb that others. I wouldn't want the whole mix to go through the same deep reverb.

When I play rock or blues guitar I don't use much reverb and I never use chorus or phazers (don't even own one). I use overdrive sparingly and prefer a clean sound. But for ambient, I go the other way. (although I still don't like chorus or phazers, and I never, ever use overdrive). Unfortunately good reverb is expensive and a cheap reverb is harsh and sometimes unbearable. Now I'm talking in terms of live performance, so a great deal depends on the room.

I'm a little more forgiving with chorus and phazers with a synth, but I don't like a lot of either when I do use the effects. Most built-in reverb on my synths aren't too good, so I'll add that through the board.

As far as basic experimental electronic music, I would say that reverb would be dependent on the track. I would think a lot of articulate textures would be lost with heavy reverb.

[The Why Project]

To come back onto IDM-specific reverb: Be free to experiment, there's
much more to reverb than only being sonic glue or a "space placement"
effect.

Why not put a expander/gate on your reverb and experiment with
triggering the expander/gate only under certain circumstances... you'll
end up using the reverb as a sound on it's own...

Or effect a nice synth in a 100% wet reverb, sample this off at certain
pitches, and use that as a melodic pad patch... use some pitch modulation
or micro-tunings and you're off on the road to proper IDM madness...

If you work with cut up loops, compress the reverb strongly within
loops (listen to SquarePusher, I'm sure he does quite a lot of this...).
I love this effect, it really can alter the dynamics of a track!

Or use and aux-send from your reverb return channel to effect parts
of the reverb (listen to the modulations within the reverb on the prepared
piano tracks on Aphex's Druqs)...

Or instead of reverb, try to use white noise... you'll be amazed how much
space you can create with just white noise, smart amplitude enveloping,
compression and some filtering!

Or... I'll just stop giving tips now before everybody sounds the same as
everybody else

Regards,

The Why Project

[mosc]

Sorry about my rant about reverb. I know it's controversial. Believe me I can really start flaming about convolution.

[elektro80]

You are among friends.. feel free to have a go at convolution..

[elektro80]

Personally I see nothing wrong with reverb, it is just another nice tool. Hmm, but I reckon I am using it 80% of the time for completely different things than actually just adding a splash of reverb on top of things. On the other hand, I am not a great fan of the late 80s / early 90s CDs created by dazed owners of Lexicon reverbs. If anything has ever contributed greatly to the demise of jazz apart from the jazz crowd, it is jazz record producers with a Lexicon in their back pocket. Saddam, my ass!

[Kassen]

[elektro80]

Abuse of reverb, or convolution or whatever is just another mainstream pop music trend. Nothing more.

I cannot see much wrong with convolution tech. I t can be argued that frankly the various vendors are promising too much right now. The usual hype. That does not however in any way reduce the usefulness of the technology.

[play]

'Verb can be a primary melodic/harmonic tool as well. I built a reaktor machine that converts midi note data into note frequencies and thence into millisecond delays for diffusers to create a 'verb that, essentially, plays notes. Throw that on a synth and program the pitches differently for the synth and it's verb and you can get some pretty interesting harmonics or user it to create a melodic drum line.

I'm no mastering engineer by a long shot but here's what little I've learned from experimenting. One way to create the illusion of space is dramatic shifts in delay lengths of verb over some period of time. Jumping from a wide to a very short verb quickly or slowly increasing delay lengths increases the perceived space. I find that rapid changes have this effect more so than subtle ones, but maybe that's just me.

Using simple pan and amplitude modulation can have a very beneficial effect on the mix as well. Doepler-type sounds, for instance can be faked using only pan and amplitude modulation, (add some slight FM for a true doepler) and you can't get much closer to the illusion of space than a deopler effect.

Here's a theory I think I'll try out when I get home. Do you think it is possible that the harmonic relationship between diffusers' delay lengths can change perceived field placement? Like for instance, a reverb with delay length of 100ms placed on a short sound and the same verb on the same sound but with a delay length half that, or a third of it, near each other in time. Would the sound with shorter delay be perceived as higher up? closer? smaller? or is it just pseudo-mystical claptrap ::)

[mosc]

Arrggg. Convolution.

Well, shit. I really don't like that surround technique of faking out your system to sound like some hall for which you have the impulse. I assume you aren't using it for that. What are you doing with convolution? I'm not in the mood to start another rant at the moment.

[elektro80]

.. just another tool for making cool sounds.. you can mangle the impulse files a lot..

I have been messing about in the bathtub recently . great sounds. Especially when the washing machine is trying to tear the house apart..

[play]

convolution is just one method of time-domain manipulation a.k.a. FFT. It can be used for a lot more than making cheesy reverbs. I think the basic technique is to modulate the frequency information of one sound with that of another, leaving the amplitude alone. Doing this with vocals and oscillators you can make vocoders but it's also neat to just do it with random sounds. You can create some very interesting sounds with little effort, much less than it takes to synthesize complex sounds.

[mosc]

Well, if you use it like that, then I've got no problem with it. It's those expensive boxes they sell with the butting that says Carnagie Hall that bug me. I'd be interested in hearing what you guys are doing with convolution. Maybe you could post a few mp3s.