Room size.

13 X 13 feet 8 1/2 high...

All small room need to be controlled for the reverberation timing... 

Passive material treatment in balance between diffusive sbsorbing and reflective surfaces

ACTIVE treatment with 32 tubes and pipes fine tuned , my mechanical equalizer, take care of ALL resonance...

An electronical equalizer modify the reponse of the speakers to the room and then modify the original "voice" of the speaker for a position very restrictive in millimeter...you turn the head a few inches and all is lost...

My mechanical equalizer modify FOR MY EARS the response of the room to each of the speakers drivers in particular without modifying the response of the speakers themselves... Instead of finetuning with a mic and chosen frequencies, the finetuning is with large bandwith response of the room/ears with human voices timbre coming from the speakers.... And all position of listening in the room are then optimized not only the main listening position...

It need to be done in a dedicated audio room.... No wife will accept 32 tubes and pipes distributed around in his living room...

The result: my 500 bucks sytem is so good that any upgrade is cancelled till i die...

Acoustic and psychoacoustic are the key.... The rest is important for sure but means way less in S.Q. without total control of the room and plastic fluid adaptation of the room to the speakers...

I would think 20’ x 25’ would be about the minimum to be called large.

Rules in audio can always be broken. I have heard an outstanding system in something the size of a walk in closet... and not a big one. I have hear terrible sounding, very expensive big components in a tiny space. I have heard a ridiculously large system in a tiny room that was breathtaking..

If you want scale and volume in a big space you need big speakers. It can be harder to get really big speakers to sound good in a small room. But it is absolutely possible. I think where the utility of the rule comes in is in cost effectiveness and in ease of achieving good sound.

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Most of us approach this from the inexpensive side. So spending $40K on speakers for a tiny room might not be putting money in the right place when $20K speakers would have done the trick... but even then it is a question of what sound do you value... if massive bass is it... then oversized speakers may be the ticket.

Like everything in audio, there is seldom a rule that does not have exceptions.

Like everything in audio, there is seldom a rule that does not have exceptions.

You are right about the relation between room and speakers size...

But no one can work mocking acoustical or psychoacoustical law.... We must work with them....No choice here....

There is no real value to defining room sizes. The point is in general you need larger speakers to deliver flat extended bass in larger rooms.

A good example is Ohm Walsh speakers. https://ohmspeaker.com. You will find every speaker there provides specs on the range of room sizes each is suited for. Too large a speaker in too small of a room will deliver too much bass. Too small a speaker in too large a room not enough. The right amount provides near flat response down to the lowest frequency spec’ed in the right sized room.

Beyond that, room acoustics will always have an effect on bass response producing more at some frequencies and less at others. That’s where setup and possibly room treatments can come in.


The Ohm Walsh very wide dispersion near Omni speaker design is pretty unique though and makes it easier to place the speakers effectively in the room for good results than more directional designs. Also closer to walls and corners which tends to reinforce bass.


The Walsh models large and small all tend to sound similar placed in the right size room.

So how big the speaker need be and how much it will cost is determined primarily by room size which makes choosing the right model per room very easy. 
More detail:

https://ohmspeaker.com/news/how-big-is-a-big-room/

Hope that helps.

My room is only 11x10 x 9 and I have Thiel CS3.7's in there. For over a decade I was hearing that you need a large room for these speakers so I held off from buying them. However, recently I put in room treatments and then Convolution file based DSP and the CS3.7's sound about 95% as good as in a much larger room. I no longer am working on improving the acoustics of the room just trying out different gear. I use ROON to run the Convolution.