Is there always a solution to room acoustics?

[Ansur]

Hello, while this is my first post here, I've been reading a lot of useful information here, for which a big thank you!

I recently finished renovating the last floor of my house, turning it into my bureau / mancave. A place for my books, guitars, and audio.
That's to say, I don't have any proper audio equipment yet. I've been going back and forwards between many configurations, but I believe I'll settle on the following:
- Genelec 8030C (x2)
- Genelec 7040A Subwoofer (x1) - probably
- Arturia AudioFuse rev2 as an all-in-one system: DAC (music will be primarily from laptop), headphone amp, and some recording

Note that I haven't been able to hear these in person, as currently all stores are closed to COVID.
Based on what I've read this would fit the room size (~40m² / 430ft²) and listening distance (~1m / 3.3ft), as well as the application: hi-fi listening mainly, and a bit of recording fun. What I'm also looking for is a system that will last - I want great sound, but I'm not looking to upgrade in the near future, I want something that should last a long time. While Genelec only offers standard warranty, their spirit seems "built to last".

What I'm mostly concerned with - and hence my question - are room acoustics. The above configuration will already set me back quite a bit of money, so I would see improving the acoustics as an ongoing project spanning probably months or even years.
I've attached a layout of the space, and as you can see it's not your typical room:
- no square space
- conventional ceilings in front and back
- cathedral ceiling towards the centre

In short, I don't expect that the sound will be great out-of-the-box, but my aim is to quietly improve once I learn more about about measuring and room treatment, and once I have the budget to apply visually appealing treatment.

Now I don't want to invest in this setup if in the end the project is in vain. Can I expect good sound with this room and this equipment eventually (and without breaking the bank in sound treatment)? Or is there something I'm missing?

 

[dasdoing]

Hello, while this is my first post here, I've been reading a lot of useful information here, for which a big thank you!

I recently finished renovating the last floor of my house, turning it into my bureau / mancave. A place for my books, guitars, and audio.
That's to say, I don't have any proper audio equipment yet. I've been going back and forwards between many configurations, but I believe I'll settle on the following:
- Genelec 8030C (x2)
- Genelec 7040A Subwoofer (x1) - probably
- Arturia AudioFuse rev2 as an all-in-one system: DAC (music will be primarily from laptop), headphone amp, and some recording

Note that I haven't been able to hear these in person, as currently all stores are closed to COVID.
Based on what I've read this would fit the room size (~40m² / 430ft²) and listening distance (~1m / 3.3ft), as well as the application: hi-fi listening mainly, and a bit of recording fun. What I'm also looking for is a system that will last - I want great sound, but I'm not looking to upgrade in the near future, I want something that should last a long time. While Genelec only offers standard warranty, their spirit seems "built to last".

What I'm mostly concerned with - and hence my question - are room acoustics. The above configuration will already set me back quite a bit of money, so I would see improving the acoustics as an ongoing project spanning probably months or even years.
I've attached a layout of the space, and as you can see it's not your typical room:
- no square space
- conventional ceilings in front and back
- cathedral ceiling towards the centre

In short, I don't expect that the sound will be great out-of-the-box, but my aim is to quietly improve once I learn more about about measuring and room treatment, and once I have the budget to apply visually appealing treatment.

Now I don't want to invest in this setup if in the end the project is in vain. Can I expect good sound with this room and this equipment eventually (and without breaking the bank in sound treatment)? Or is there something I'm missing?

you better ask on Gearslutz.
and read there, A LOT

 

[infinitesymphony]

Every room presents its own difficulties. Your room is not a square, which is good, and it's not symmetrical, which could be good or bad depending on the way reflections bounce around differently on each side. Anything you can do to break up and decrease resonance and reverb time (not sure how large your room is) will be helpful. You could make the room more symmetrical by adding a hard surface parallel to your entry wall. You may or may not need to fly clouds on the slanted ceiling portions; depending on the monitor position it's possible that the upward slant could work in your favor.

I recommend starting with Genelec's Monitor Placement guide, which will help you to get your monitors into their optimal position.

After that, when you're ready to start treating the room, read Genelec's Calibration & Acoustics guide. Skip the calibration portion and focus on the room treatment section.

Finally, fine tune the frequency response to your room using the DSP method of your choice.

Other helpful starting points:

http://arqen.com/acoustics-101/room-setup-speaker-placement/

I'm no expert, so hopefully the real experts will also chime in.

 

[pozz]

General advice is to place speakers where you are comfortable having them, ideally in a symmetrical layout (not necessarily facing a wall, facing a corner is ok too), measure, EQ first. If you are unsatisfied or if there are real issues with uneven reverb times, buy the thickest absorbers you can.

 

[RayDunzl]

Ill-Educated Opinion:

Listening at low levels, you may not even notice the room.

Problems will likely become more noticeable with more volume.

Unless it's as lively as some bathrooms.

Will it have some carpet, at least?

Furnish it and listen and measure before deciding on treatments, would be my cheap advice.

Hand-claps are an effective excitation.

Not a professional example, but...

Area carpet example, pehaps a better fit for your immediate situation:

The beef starts at about 2:50

 

[pozz]

Hand-claps are an effective excitation.

Not a professional example, but...

(video)

Sorry Ray, I disagree for handclaps and the video.

I have a paper somewhere which analyzes (seriously) the optimal handclap. Placement of hands, force of the clap and so on. As you'd expect the excitation is uneven and midrange centric. The usual sweep, chirp, noise or impulse does a better job.

That video is a very wrong way to do it. Using 1" or 2" foam directly on the wall (so no an air gap) will absorb reflections for highs and high mids and leave the rest wild. It will sound very uneven. Maybe at first you'd like how crisp everything is, but then you'd notice the boom and mud below.

Speaking as someone who used 8" and 5" (with 3" air gap) absorbers.

Carpet is ok (less absorption than you'd think; not sure if that was the point of the video since I didn't watch it).

 

[RayDunzl]

Sorry Ray, I disagree for handclaps and the video.

Yeah, it's not calibrated...

And the video is just an example of a severe room, which most empty ones probably are, with a severe excitation (the snare drum).

The usual sweep, chirp, noise or impulse does a better job.

But the first post (the poster's first post, too) says "I don't have any proper audio equipment yet."

Carpet is ok (less absorption than you'd think; not sure if that was the point of the video since I didn't watch it).

I have carpet, and found it to be a bit infomative (again without quantification).

 

[pozz]

Fair 'nuff

 

[Mike-48]

This series of videos on YouTube covers a wide variety of acoustics information. I think you'll get a good background from them. The author does studio acoustics for a living and gives clear presentations that are, as far as I can tell, based on real acoustic science and considerable experience.

 

[tmtomh]

Hello, while this is my first post here, I've been reading a lot of useful information here, for which a big thank you!

I recently finished renovating the last floor of my house, turning it into my bureau / mancave. A place for my books, guitars, and audio.
That's to say, I don't have any proper audio equipment yet. I've been going back and forwards between many configurations, but I believe I'll settle on the following:
- Genelec 8030C (x2)
- Genelec 7040A Subwoofer (x1) - probably
- Arturia AudioFuse rev2 as an all-in-one system: DAC (music will be primarily from laptop), headphone amp, and some recording

Note that I haven't been able to hear these in person, as currently all stores are closed to COVID.
Based on what I've read this would fit the room size (~40m² / 430ft²) and listening distance (~1m / 3.3ft), as well as the application: hi-fi listening mainly, and a bit of recording fun. What I'm also looking for is a system that will last - I want great sound, but I'm not looking to upgrade in the near future, I want something that should last a long time. While Genelec only offers standard warranty, their spirit seems "built to last".

What I'm mostly concerned with - and hence my question - are room acoustics. The above configuration will already set me back quite a bit of money, so I would see improving the acoustics as an ongoing project spanning probably months or even years.
I've attached a layout of the space, and as you can see it's not your typical room:
- no square space
- conventional ceilings in front and back
- cathedral ceiling towards the centre

In short, I don't expect that the sound will be great out-of-the-box, but my aim is to quietly improve once I learn more about about measuring and room treatment, and once I have the budget to apply visually appealing treatment.

Now I don't want to invest in this setup if in the end the project is in vain. Can I expect good sound with this room and this equipment eventually (and without breaking the bank in sound treatment)? Or is there something I'm missing?

There is always a solution to room acoustics. However, there is not always a perfect or total solution, and there is not always an affordable or aesthetically pleasing solution.

That said, it really depends on what standard you are trying to reach. As per @RayDunzl 's comments above, the most obvious - and most irritating - type of room problem is pretty easy to address: slapback or flutter echo at the midrange frequencies that humans are most sensitive too. Put simply, that awful "bathroom" echo when you talk or clap your hands in an overly "live" room. Now, as @pozz notes, fixing obvious midrange echo isn't going to make a bad room into a truly hi-fi room - it's only going to remove the most obvious, most cringe-inducing issue.

My experience is that carpet is a shockingly good room treatment. Yes, most carpet has mediocre absorption qualities. But wall-to-wall carpet or a large rug covers so much more square footage than a wall panel that it provides a lot of absorption and really helps "un-liven" the room. Also, if you listen in a seated position as most people do, and your ceilings are at least 8 feet tall, then the floor is actually the earliest reflection point in the room, which makes carpet a very high-impact improvement.

Beyond that, though, I do have to again agree with @pozz that you're not going to make a dent in taming frequencies below about 300Hz (give or take) unless you install wall (and/or ceiling) panels of some thickness and ideally also with an air gap behind them, which increases the absorption. Because of limitations in my room (and budget limitations I had when setting it up), I have a couple of 3.5-inch thick panels with a 1.5-2 inch air gap placed on the corners behind my speakers and on the ceiling midway between the speakers and my listening sports; and some 2-inch panels I got cheap off Craigslist, with special brackets I got from the manufacturer to enable them to be placed 2 inches off the wall. Those treatments all help a lot and they cost less than $750 total - but I still have a mild bass mode that manifests itself at 80Hz and 160Hz and has to be controlled with EQ. I could probably reduce that issue by spending a few hundred bucks on thicker absorbers for the corners, but the issue is sufficiently modest that I just can't be bothered at the moment - I really enjoy my music as-is and so upgrading my absorbers is on my to-do list but not urgent.

So can you get decent room behavior for not a lot of money? Absolutely! Can you get truly excellent measured in-room performance without spending a good deal more money and putting up with much larger/thicker treatments? Unlikely. But you can still be a very happy listener if you are willing to spend 20-30% of what you paid for your speakers on some room treatments.

 

[dasdoing]

if you (plan to) put a decent amount of absorbtion, you better have no carpet, else it will be too dead (and the carpet has an uneven effect anyways).

foam (mis)treated rooms sound very bad. you kill the reflections only in the high frequency range. what happens now is you hear the mid range reflections even more. like when you have a boosted bass when you attenuate above 200Hz.

your room is very badly shaped. main problem is the hall; is there a way to remove it long term?

 

[mitchco]

Hello, while this is my first post here, I've been reading a lot of useful information here, for which a big thank you!
...
Now I don't want to invest in this setup if in the end the project is in vain. Can I expect good sound with this room and this equipment eventually (and without breaking the bank in sound treatment)? Or is there something I'm missing?

Post some measurements using REW so we can get an idea of your acoustic space. Most rooms untreated, but furnished usually fall within industry guidelines. What you are missing is digital room correction which is pretty much mandatory below your rooms transition or Schroeder frequency unless you want to stuff you room with bass traps (not recommended).

 

[RayDunzl]

Now I don't want to invest in this setup if in the end the project is in vain.

Nobody has a perfect room.

What have you had before?

---

When I bought this house, I looked at this room, and my analysis consisted of standing in it and saying "This'll work".

And it has.

---

It was a quick purchase... I hate "shopping".

Saw online Wednesday evening. Bank owned foreclosure.
Viewed Thursday, Sent offer to Bank Rep.
Bank accepted Friday.
Monday the Bank got all the paperwork together.
Closed Tuesday.
Met last day deadline for $8,000 "First Time Homebuyer" Obama Credit (though I really wasn't)

 

[tmtomh]

if you (plan to) put a decent amount of absorbtion, you better have no carpet, else it will be too dead (and the carpet has an uneven effect anyways).

foam (mis)treated rooms sound very bad. you kill the reflections only in the high frequency range. what happens now is you hear the mid range reflections even more. like when you have a boosted bass when you attenuate above 200Hz.

your room is very badly shaped. main problem is the hall; is there a way to remove it long term?

I'm sorry but this is nonsense. Preserving floor reflections in the hope of keeping the room from sounding overly "dead" is a terrible idea. First off, unless you have speakers with coaxial drivers or otherwise unusually good vertical directivity, floor and ceiling reflections tend to be worse than side-wall reflections and the better advice is to install carpet (and ceiling treatments, especially for a high/vaulted ceiling), but not overly damp/absorb on the walls.

In addition, one has to apply a pretty large number of wall panels to start overdamping a room. A half-dozen panels (just to pick a random number) on the walls of a space like the OP's is not going to even begin to overdamp the room, even with carpet installed.

 

[Mike-48]

It's hard to add to what @tmtomh and other have said already. But I thought I'd mention my framework, sort of a checklist. Usually when looking at a room I think of the following:

1. Killing slap echo. It is very irritating and you don't need a lot to kill it.
2. "Trapping" bass. This requires big stuff. The most noticeable result is shortening reverberation times, which can improve clarity a lot. In my experience, it's hard to have enough bass traps to change measured FR by more than a dB or two, but despite that, bass traps make a big difference in what you hear.
3. Killing or breaking up first reflections. They are irritating along the lines of slap echo. I agree that a rug or carpet between the speakers and listener is helpful to treat the floor.
4. Boundary issues. Make sure the main speakers are different distances from the front than they are from the sidewalls or other surfaces. Genelec suggests putting the speakers near the front wall for this reason.
5. DSP for the deep bass. Close to impossible to correct issues below 100 Hz without it. And it can be useful up to the Schroeder frequency (as @mitchco said) -- even above, in my experience.

Of course, before doing any of that, it really helps to find good positions for everything.

As far as "overdeadening," it can be avoided by using panels with a combination of absorption and scattering. Examples are the RPG BAD panels, any panel made by ASC (they use mylar strips for reflection), the Alpha panels of GIK. There are many others.

 

[Senior NEET Engineer]

I'm sorry but this is nonsense. Preserving floor reflections in the hope of keeping the room from sounding overly "dead" is a terrible idea. First off, unless you have speakers with coaxial drivers or otherwise unusually good vertical directivity, floor and ceiling reflections tend to be worse than side-wall reflections and the better advice is to install carpet (and ceiling treatments, especially for a high/vaulted ceiling), but not overly damp/absorb on the walls.

In addition, one has to apply a pretty large number of wall panels to start overdamping a room. A half-dozen panels (just to pick a random number) on the walls of a space like the OP's is not going to even begin to overdamp the room, even with carpet installed.

What acoustic problem are you trying to solve with large surface area of carpet on the floor?

 

[sfdoddsy]

Feeling overwhelmed yet Ansur?

Folk tend to over-analyse here.

Your room is better than most. The variations in width and height are potentially better than having a classic rectangle.

My question, given your admitted newness, is whether you want good or perfect.

Fill you room up with the stuff of life (sofas, rugs, bookcases etc etc) and you’ll get good sound without having to do a thing. Simple Room EQ will give you (comparatively) great sound.

You could then add various room treatments which may or may not improve things 10% further. It’s that extra 10% which costs 90% more.

Will you settle for great?

I would.

 

[Ansur]

Overwhelmed, but also reassured. Thank you all for the input and links to videos and guides.
It might be a good idea then to invest a bit more and buy 8330A's instead, as it seems this will already go a long way.

I would settle for "great", though there is also the learning aspect - being able to interpret room measurements sounds interesting and useful down the line.

 

[tmtomh]

What acoustic problem are you trying to solve with large surface area of carpet on the floor?

Refer to my prior comment. Carpet reduces what is usually the earliest reflection relative to the listening position (floor), and it also reduces reflections on the axis that typically has the most directivity issues (vertical). Not to mention, the mediocre absorption qualities of carpet nevertheless are effective at the midrange frequencies where @amirm 's test almost always show a dip due to vertical directivity issues.

It's not about using carpet in a precise manner to address a particular room issue per se. It's about how someone with an echoey room can most easily and effectively reduce the "overly live" quality of the room. Carpet is effective in that regard. Carpet is not sufficient by itself to correct the full range of reflection/room mode issues of course. And it is certainly possible to successfully address room issues without carpet. But for a typical home listening environment, carpet is an excellent first step and it makes a lot of sense in many cases because it's more easily integrated into most home environments than a large number of acoustic panels might be.