Rooms

Small rooms are almost impossible to make sound good#

The smaller the room, the harder it is to treat. Low frequencies need thick absorption, and the smaller the room, the thicker the rockwool has to be, which makes the room smaller still. Below a certain footprint you hit a tipping point where it just can't be treated.

Big speakers don't rescue it either. They need a metre and a half or two for their drivers to integrate, so in a small room you can end up sitting against the back wall, in an antinode, with far too much bass. In theory big speakers in a superbly treated small room would be fine. In practice it isn't feasible.

For mastering you need at least about 30 square metres. Below that you'll struggle to get the low end steady and even, the room modes get weird, and you can't position the equipment properly. If some professionals get great results in smaller rooms because they know their room's faults, fair enough. But most home studios physically can't be mastering grade, so for mastering it often makes more sense to take the room out of the equation.

Foam makes your room worse#

Common panels of foam do nothing below roughly 500 Hz - 1 kHz. Above that they suck the life out of the room, and below it the room still sounds like a bathroom. Many people clap their hands, hear less reverb and think the job's done. It isn't, because a hand clap is mosly a mid-high frequency sound.

You still can't judge the bass or the lower mids.

So some of them rip the foam off and buy thin commercial broadband absorbers, which are basically rockwool in a frame. Now it tends to sound like a bathroom below 300 or 400 Hz instead. Proper treatment is the opposite of foam: thick low-frequency absorption and bass trapping, plus diffusion to scatter the highs so you don't kill the top end.

DIY absorbers are good enough for an all right room#

I would start at the hardware store, not the audio shop. Wooden frames, rockwool batts (or another material if you can source it and find it more health conscious), a thin polythene painter's sheet over the front to keep the fibres in, then any fabric you like stapled on top. Wear gloves and a mask. People object that the plastic blocks the bass. It doesn't. At most it reflects something around 10k, and we don't care about 10k. A room's worth of absorbers costs a few hundred quid, about what a shop charges for three or four panels.

That gets you an all right room to work and listen in, though not one for critical decisions. Either way, treatment usually does far more for what you hear than the audiophile cables people buy instead.

You can't EQ your way out of a room#

Room-correction EQ, hardware or software, can't get around the physics. A correction curve is valid at one head position. The second you move your head, you have a different sound and the curve is wrong.

Turning it down doesn't tame room modes#

One claim is that if you turn the level down, you won't excite the bass so much, so it will be easier to judge the bass - or maybe even that this results in a flatter response somehow.

It doesn't because a resonance decays at the same rate regardless of whether it's loud or quiet. Monitoring quieter only pushes the ringing below your threshold of hearing but then other parts of the mix get pushed below the threshold too.

It's like saying that if you want less surface noise on a record, play it quieter. Monitoring quietly isn't a substitute for acoustic treatment and level matters for its own reasons: see monitoring level.

A kick drum test for the low end#

Here's a quick test. Play Radiohead's "Feral" on your speakers and concentrate on the kick and the low end. Then listen again on a decent pair of headphones. In a flawed room with ported monitors, many people will hear the kick sounding longer on the speakers.