Your couch is fine. Your bookshelf is fine. Even the bed is probably fine.

What’s worth worrying about is the hard stuff sitting right behind your chair.

I know that’s not how it feels when you sit in your room and look around. The sofa at the back, the shelf full of books, the guitar on the wall, the second desk because the room is also an office. Every one of them looks like it could be doing something to your sound. (Mike Senior called it “a whole bunch of other crap in the studio” when we recorded my latest video. He’s got a sofa at the back of his room too.)

Here’s my honest answer. Most of it won’t break the sound at your listening position. You’d have to pack your room pretty full before it gets in the way of your work.

Where it does get annoying is measurements. Fill a room with stuff and the graphs get very hard to read, because you can’t tell what’s the room and what’s the furniture anymore. But that’s a problem for the graphs, not for your mix.

So instead of me guessing what’s in your room, here are the three questions I ask. They work on anything.

Three questions for anything in your room

How big is it?

How close is it to your speakers and your listening position?

Does it soak sound up, or bounce it back?

Size comes first, because it tells you which frequencies can even notice the object. It’s like waves on a lake. A reed sticking out of the water does nothing to a long, slow swell. The wave just wraps around it. A big concrete pier is a different story. The swell hits it and comes back.

Sound works the same way. A wave only “sees” an object that’s roughly as big as its wavelength or bigger. 100 Hz has a wavelength of about three and a half metres (a bit over 11 feet). So unless something in your room is that big, it’s basically invisible to 100 Hz and everything below. Your room modes don’t care about your pot plant. A pot 20 to 30 centimetres across only starts to matter from around a kilohertz upwards.

Distance comes second. The closer an object, the louder its reflection is when it gets back to you, and the sooner it arrives after the direct sound. Both make things worse. A loud, early reflection interferes with the direct sound. That’s comb filtering, and it thins the sound out. It also smears your stereo image, so your brain has a harder time placing things.

Material comes third. Soft and porous stuff absorbs. Hard and flat stuff reflects.

Now let’s put the usual suspects through it.

The couch and the bed

A couch is two or three metres long, maybe a metre deep and a metre high. So it’s big enough to affect things from the low hundreds Hz upwards.

But it’s mostly soft. A fabric couch absorbs the highs, and the cushions inside take a bit more on top of that. With leather, some of the highs bounce off the surface. Either way you get a not-so-predictable mix of absorption and a little reflection, and absorption usually wins. If it’s fabric, you’re pretty safe. It won’t send much back to your listening position.

A bed is much the same. Mattress, duvet, pillows, all absorbing. Maybe the frame reflects a bit.

What a bed does do is break symmetry. Nobody puts their bed centred right behind the listening position. It sits in a corner or off to one side, so one side of your room absorbs more than the other. Same goes for a couch that isn’t centred.

That’s worth knowing. But it’s not worth panicking about. More on that further down.

The bookshelf

You’ve probably heard that a shelf full of books works as a cheap diffuser. I get why. All those different depths look a lot like one.

Let’s run it through the questions. As a whole, the shelf is big, so it might nudge the room mode pattern slightly. The books themselves are small. A spine is a few centimetres wide and 15 or 20 centimetres tall. So that irregular pattern only affects frequencies from several kilohertz up.

And a diffuser isn’t just irregular. It works through interference. Each little step reflects sound, and all those reflections interfere with each other in a controlled way. That’s why the depths follow a specific mathematical sequence. Your book collection doesn’t.

So the books scatter a bit of top end and take the edge off a flat wall. Better than nothing. But a diffuser it is not.

The rack behind your chair

This is the one I’d actually look at.

You’ve seen it in pro studios. A low table or a row of 19-inch racks right behind the mixing position. 

Run the questions again: It’s big, from about a metre across up to several metres. It’s hard and flat, so it reflects pretty much everything. And it’s close, right behind you. On top of that it’s usually angled slightly upwards so any reflection comes straight back to your ears.

Only one thing works in its favour. It sits low, below your speakers and your ears, which takes a little energy out of the reflection. That’s it. All told, these are pretty bad for the sound.

That’s one reason you rarely see measurements from pro studios once all the gear is back in the room. It doesn’t make the listening position any better, and some of it has quite a strong effect.

Ideally what you want to do is put racks low and off to the side of your mixing position. From there, a reflection can’t find its way back to your ears, because the angles don’t work.

The guitar on the wall

Instruments are the one thing in your room that has a sound of its own. Guitars, any string instrument, the drum kit in the corner. Put energy into the room from your speakers and they can start to resonate along with it.

I see that pop up in measurements all the time. So if you want clean measurements, take them out of the room first.

But while you mix? Usually it’s too quiet to notice. Your brain is very good at separating sounds, so even if you can hear it, it may not bother you. If it does, put it somewhere else.

What actually needs protecting

Put it all together and you get one rule. Keep the line of sight between your speakers and your ears free. Anything you don’t need in front of you every day goes to the sides, and down.

Do that, and the rest of the room can just be a room. If something really does wreck the sound, you’ll notice. In my experience it’s usually pretty obvious and fairly straight forward to do something about.

That’s also where symmetry comes back in. If the bed or the couch tips your room off balance, absorption in the right spots can counteract a lot of it, and so can speaker calibration. 

Why pro rooms look so empty

So why does a high-end mastering room look the way it does? Big speakers. Often a small desk. Everything is symmetrical. Almost nothing else in the room.

Because the higher you climb the skill ladder, the more sensitive you get to small imperfections. At that level a reflection off a rack, or one side of the room being a little softer than the other, does matter. The room is built around one job, and everything else is secondary to that.

But in a home studio you can turn that around. Get the fundamentals right (where you sit, where the speakers go, a clear line of sight) and let everything else land where it lands.

How far up that ladder you go is your call. It comes down to how much you prioritize pure sound, compared with everything else you use your room for.

And don’t forget the part no graph shows. If you can’t work comfortably in your room and get into a flow, the cleanest response in the world won’t help you much.

The couch can stay.