Room acoustics explores how sound behaves within enclosed spaces, and it has a far bigger impact on what you hear than most people expect. Hard surfaces like concrete or glass reflect sound waves, creating echoes and reverberation, while soft materials such as carpets or curtains absorb them. To understand exactly how that plays out in a real listening room, we sat down with Roland Hoffmann, Director of Product Marketing at Steinway Lyngdorf, for an Academy session on room acoustics.
Listen to the full conversation below, or read on for the highlights.
Why Loudspeaker and Room Are Acoustically One
A loudspeaker isn’t like a television screen — a static object you simply look at. It emits sound waves into a space that, for most people, has a ceiling, a floor and four walls. Those waves don’t travel in a straight line from speaker to ear; they get trapped in the room and interact with it. Acoustically speaking, a loudspeaker and the room it plays in are effectively one system, and the room has a very strong impact on what you actually hear.
Picture Sound Waves as Water Waves
One of the easiest ways to understand room acoustics is to imagine sound waves as water waves: low frequencies behave like big, powerful waves, while higher frequencies are more like fast ripples. Picture a speaker emitting those waves into a room. A bass wave travels to the wall behind the speaker — and since it can’t go anywhere, it comes back. The same happens at the side walls. Every reflection creates a new wave that interacts with the original one, and it becomes easy to imagine just how messy that can get once reflections start arriving from every direction at once.
How Direct and Reflected Sound Overlap
That’s the difference between direct sound (what travels straight from the speaker to your ears) and indirect sound (everything that bounces off a surface first). The wall behind your listening position matters just as much: those waves travel there, bounce back, and arrive delayed — overlapping with whatever sound is already in the room. A bare wall reflects quite hard, while a bookcase or a set of shelves breaks the wave up. Exactly the same principle applies to every reflective surface in the room.
Why a Cube-Shaped Room Is the Worst Case
The shape of a room matters enormously, but it’s usually the one thing you can’t change unless you’re building or renovating. The worst-case scenario is a room shaped like a perfect cube — for example, three metres wide, three metres long and three metres high. Every acoustic problem that occurs at that three-metre dimension gets multiplied across all three axes, because width, length and height are all identical. The result: certain frequencies become far too loud, others cancel out, and hard reflections pile up in the same places.
The Golden Ratio Approach to Room Dimensions
The fix, where possible, is to move away from equal dimensions. Making the width, length and height of a room unequal — ideally something close to a golden ratio — breaks up standing waves in a much healthier way. The more uneven the proportions, the better, and it’s also worth avoiding simple doubling: a room measuring three by six metres is better than a perfect cube, but it’s still an exact double, so some problems will still be exaggerated. Most people can’t simply redesign their room around this principle, but understanding it makes it much easier to recognise why a particular room has a problem in the first place — for instance, discovering through measurement that the width and length are nearly identical.
Does Bass Perform Better in a Bigger Room?
In general, yes. A smaller room fills up with bass energy more easily and can quickly become too much, whereas in a larger room, bass waves spread out more evenly and have more space to dissipate. That said, a very large room — think of a hall — introduces its own trade-off: reverb, the delayed reflection returning to your ears, takes longer to arrive, making the space sound more echoey. But in general, the bigger the room, the less bass compression you’ll experience.
Tip One — Find the Right Spot for Your Speakers by Ear
With five practical, cost-free tips on the table, the first is simply this: find a good spot for your speakers by ear. You don’t need to be a sound engineer — just a pair of speakers, some music, and a willingness to do A/B comparisons. Move the speakers closer together or further apart, push them back toward the wall or pull them forward, and pay attention to how each change actually sounds. Trust your ears first; how something measures matters far less. Speaker placement, and how the speakers interact with the room, has by far the biggest single influence on the sound.
Tip Two — Choose Your Listening Position With the Stereo Triangle
Before getting into different amplifiers, streamers or DA converters, room acoustics rules — and that starts with where the speakers are and where you sit. A good starting point is the classic stereo triangle, because that’s exactly how the music was mastered, recorded and mixed in the studio: engineers sit in that same triangle, in a room they’ve spent real effort optimising as a working environment. The closer you get to that configuration, the closer you get to hearing the music as it was intended. Beyond that, there’s no universal rule, blog post or forum thread that can tell you the ideal listening distance for your room — you have to experiment and trust what genuinely sounds better to you.
Tip Three — Furniture and Soft Furnishings Are Natural Room Treatment
An empty room sounds terrible; a room filled with furniture, fabric and everyday objects usually sounds surprisingly good. Bookcases, tables and other objects break up sound waves and even them out in a beneficial way — it barely matters exactly where a piece of furniture sits, only that it’s there. Soft fabric, drapes and carpet all help further. This is one area where it’s genuinely difficult to overdo it, since ordinary furnishings absorb and diffuse sound in a mild, natural way rather than aggressively.
Tip Four — Match the Speaker Size to the Room
It’s not just about finding the right spot for a speaker — it’s about choosing the right size of speaker for the room in the first place. A speaker that’s too large for its room tends to overpower the bass no matter how it’s positioned, while a speaker that’s too small, or placed too far from the listening position, simply runs into the limits of physics. Getting this right depends on room size, listening distance and speaker placement together — which is exactly where a good dealer adds real value, letting you compare a short list of candidates and, ideally, audition them at home rather than relying on a showroom impression or a spec sheet comparison alone.
Tip Five — Room Correction Fixes Problems Before They Happen
The fifth tip is room correction — using DSP, whether built into an active speaker or a capable amplifier, to go further than any amount of manual trial and error. Repositioning speakers by ear is inherently a subjective process; a room correction system, by contrast, measures the room’s actual response and can address problems with real precision. In principle, every calibration system works the same way: it measures the room and adjusts the original signal in the digital domain before the sound ever reaches the speaker — for example, reducing signal energy around a boomy frequency like 80Hz so the speaker never sends that excess energy into the room in the first place. That’s a more elegant approach than letting the problem happen and only afterwards trying to absorb it with a bass trap in the corner.
Why You Can’t Simply “Fill In” a Bass Null
Room correction can also help with the opposite problem: a lack of energy at certain frequencies, caused by standing waves cancelling each other out at specific points in the room — commonly called nodes or nulls. A very simple correction system might try to compensate by pumping more energy into that gap, but that’s a mistake: a null is a genuine cancellation, a matter of physics, and no amount of added energy fills it back in — it just makes the speaker and amplifier work harder for no audible benefit. A properly engineered correction algorithm avoids that trap rather than blindly boosting a frequency that’s being cancelled out in the room itself.
Why More Acoustic Panels Isn’t Always Better
Before reaching for a shopping cart full of acoustic treatment, it’s worth starting with natural room treatment: drapes, carpet, fabric and cushions, which work gently and are hard to overdo. Dedicated bass traps, panels and diffusers are genuinely effective, but precisely because of that, they’re also easy to overuse. Buying ten panels for a room that sounds “too echoey” often backfires into an unnaturally dead-sounding space, and a bass trap placed to tame one problem frequency — say, that same 80Hz example — rarely stops there; it typically removes more energy than intended, leaving the bass sounding thin and lean. These are precision tools, meant for a specific frequency and a specific amount of reduction in decibels — which means using them well really depends on having measured the actual problem first, not just reacting to how a room feels.
The Takeaway
Five tips, none of which cost a single euro: get the speaker placement right by ear, find your listening position using the stereo triangle as a starting point, furnish the room properly, choose a speaker that actually suits the room, and consider room correction as the more scientific finishing step. All it costs is time and a bit of effort — and it has more impact on how a system ultimately sounds than most of the gear decisions that come afterward.
Frequently asked questions
My listening room is almost square — why is that a problem?
Because equal dimensions multiply acoustic problems instead of spreading them out. The worst case is a perfect cube, for example three metres wide, long, and high: any problem that occurs at that one dimension happens simultaneously on all three axes. The result is that certain frequencies become far too loud, others cancel out, and hard reflections pile up in the same places. Room shape is usually the one thing you can’t change, but understanding why a room has a problem makes it much easier to recognise.
What is the golden ratio approach to room dimensions, and why does it work better than equal or doubled proportions?
Making a room’s width, length, and height unequal — ideally close to a golden ratio — breaks up standing waves in a much healthier way than equal dimensions do. It’s also worth avoiding simple doubling: a room measuring three by six metres is better than a perfect cube, but it’s still an exact multiple, so some problems remain exaggerated. The more uneven the proportions, the better.
How many acoustic panels do I need to improve my room?
Probably fewer than you think — and don’t start with panels. Curtains, carpet, fabric, and cushions work gently and are hard to overdo. Dedicated bass traps, panels, and diffusers are genuinely effective, but precisely because of that, they’re also easy to overuse: buying ten panels for a room that sounds “too echoey” often backfires into an unnaturally dead space, and a bass trap aimed at one problem frequency typically removes more energy than intended, leaving the bass thin and lean. These are precision tools, meant for a specific frequency and a specific amount of reduction — which means measuring the actual problem first matters more than reacting to how a room feels.
What is the stereo triangle, and why is it a good starting point for a listening position?
The classic stereo triangle — equal distance between both speakers and the listener — mirrors how a mix was made in the studio, where engineers sit in that same triangle, in a room they’ve spent real effort optimising. The closer you get to that configuration, the closer you get to hearing the music as intended.
Can room correction fix any acoustic problem?
Not everything. DSP-based room correction measures the room’s actual response and adjusts the signal digitally before it reaches the speaker — for example, reducing energy around a boomy frequency like 80Hz so that excess never enters the room in the first place, which is more elegant than absorbing the problem afterwards with a bass trap. But the opposite problem, a null, is a genuine cancellation caused by standing waves cancelling each other out at a specific point — that’s physics, and pumping in more energy doesn’t fill it back in; it just makes the speaker and amplifier work harder for no audible benefit. A well-designed algorithm avoids that trap rather than blindly boosting a cancelled-out frequency.
