Lets have fun and create my new listening room

[banpuku]

Hi, I am moving into a new home with an empty 9' ceiling basement. Attached are photos of the basement and blueprints. I would like to get input on ideas for room location, dimensions, etc.

A bit about my system and listening preferences:
1. I listen primary to chamber music at about 90-94 db. I typically sit about 8-10 feet away from my Ilumnia Magister speakers (BTW: I love these speakers!!! Very balanced, dynamic and distortion free). My amps are 5W DHT monoblocks (C3g drives EML 45B) that easily drive the Ilumnia Magisters.
2. Empty nesters, so noise traveling up to first floor is not a problem. Noise traveling down from first floor not a huge problem, but foot fall might need to be eliminated with a high mass ceiling in the listening room.
3. On the blue prints and photos, notice the HVAC duct work. Ideally, I don't want to have that running thru the room, but not sure if the duct work can be avoided. I won't move the duct work. Only option is to locate the listening room aaway from duct work.
4. In my prior 2 listening rooms, the dimensions were a bit small (20L x 12W) and (17L x 14W). Ideally, I am thinking of 25 x 14 or something like that. I don't want the room too big because I do near field listening.

Some questions (just thinking out loud):
5. Should any of the walls be splayed in order to eliminate parallel walls?
6. Thoughts on making the front wall or back wall a large diffusion panel? See attached photos for ideas on decorative diffusion ideas.
7. Avoid the HVAC duct work completely? If so, this limits the size of the room.
8. If the room is adjacent to the stairwell, does the stairwell present any acoustic problems?

Any ideas are welcome. Let's make this fun!
Pat

 

[sbnx]

Hello, This is a huge room. Some thoughts.

you don't really want to hear the rumble of the HVAC system. So you may have to do some insulation/Damping work on the duct.

Your room is so large that I don't thing you are going to have major issues with modes. It is odd shaped.

I don't know what you have planned for the rest of the space. However, I am a believer that you want the speakers as far from the wall as possible. I posted two pics of where I would start with the listening position and speaker position. in both you will not have any SBIR issues from the wall behind the speakers as it will be below 20Hz. You would have to find the best sofa position for the best bass balance then position the speakers for best sound.

In general you would like to have left/right symmetry where ever you place the speakers. I prefer AA for this reason.

Will the stairwell cause acoustic problems? Well, the short answer is yes. All things influence the acoustics of the room.

 

[sbnx]

Of course if you don't mind everything in the middle this is probably the best place.

 

[Cellcbern]

See my posts on my testing of the ZR Acoustics panels and take a look at the DHDI website:

Delta H Design

Check out SFSCS.org

deltahdesign.com

A disruptive technology that obviates the need for bass traps and would place the speakers very close to the panels/wall behind them, perhaps allowing for changes in listening room dimensions.

 

[LenWhite]

This is what I did when adding a dedicated listening room to my house in 2015.

Acoustic Frontiers (acousticfrontiers.com) established the optimum room size consistent with a house addition, designed the room acoustics and provided optimum inside wall dimensions.

The media room acoustic "foundation" consists of an isolated wall system comprised of 130 Kinetics IsoMax clips attached to 1-1/2" furring strips nailed to CBS blocks on all four walls. 440 linear feet of 25mm hat channel is supported by the isolation clips. R-11 open faced fiberglass (3-1/2" thickness) fills the empty areas between the CBS walls and drywall. Soundboard XP damped drywall is attached to the hat channel. Acoustic sealant seals the areas between the top, bottom, corner areas of the damped drywall.

The ceiling utilizes Soundboard XP attached to the ceiling joists. The media room attic has R-38 fiberglass insulation. A knee-wall with attached R30 fiberglass insulation separates the media room attic and the original structure interior attic area.

The A/V electronics are served by a dedicated 100A electrical sub-panel with (4) 20A circuits and 20A Furutech GTX-D duplex receptacles. Twisted pair wiring (#12) is used for each circuit with the neutral and hot wires wrapped on 2" centers and the ground wire placed parallel in PVC conduit. A paper presented at the 2010 AES 129th Convention shows this method has the lowest ground voltage induction tested.

The media room has a dedicated 1-1/2 ton A/C system. Large exhaust ducts in each room corner, and a large return duct on the rear ceiling leading to the air handler/evaporator minimizes room noise.

Acoustic Frontiers incorporated my existing Rives Audio ceiling "clouds" and using room dimensions and frequency measurements specified the interior room acoustic products and locations. The acoustic design creates a flatter frequency response; lowers the room reverberation time; and provides bass trapping. Clarity, sound staging, and imaging are all improved while keeping the room as live as possible.

The interior acoustic panel positioning:
- Ceiling: (4) 6'x6' wood frame acoustic "clouds" hung with all thread from the ceiling joists room centered. Each wood frame consists of (4) 2'x4' RPG BAD panels supported by the frame support structure. UltraTouch R19 sound absorption batts are placed on top of the structure.
- Front wall: (2) 39"x59" RPG Modex type 1 plates (outward positions), (2) 39"x59" RPG Modex broadband panels (inward positions). Panels with 6" spacing except at side walls, hung 23" from floor.
- Side walls: (3) 2'x2' RPG BAD ARC panels @ the L/R wall first reflection points; (3) 2'x2' Listen Audio natural birch diffusers @ the L/R 2nd reflection points; (3) 2'x2' Listen Audio natural birch diffusers flanking the listening positions on the R sidewall and behind the listening positions on the L sidewall. All panels hung 18" from floor.
- Rear wall: (1) 6'x6'x12"d absorber box (R38 fiberglass filled) centered. The existing floor standing RPG BAD panel templates wrapped with acoustic cloth attached to the front of the absorber box. The absorber box is hung 26" from the floor.

There are some construction pictures on my Audiogon webpage https://systems.audiogon.com/systems/5013

Best thing I ever did for music listening - good luck.

 

[Kingrex]

I have read horror stories of people doing their rooms without a professional team with a solid track record creating the design and providing details on how to build the walls and ceiling. You really should hire a pro like Foley or Hedbeck or maybe Acoustic Frontier I know nothing about AF. Wouldn't it be heartbreaking to screw it up and have odd room modes. Dips and peaks, phase reflection issues. I have a friend who tried this. He studied for years what to do. It took 5 tries to get it right. Put it in, rip it out, put it in, rip it out.

 

[sbnx]

I agree with Kingrex. If you are going to undertake a major, whole room treatment then I would contact an acoustician. But, your room is pretty large so you probably won't need a whole lot. Also keep in mind when talking to acousticians. Home theater is a whole different approach than 2 channel stereo. Home theater is usually way more damped. Here are some names to consider.

Anthony Grimani -- Sonitus/PMI Engineering
Norm Varney -- AV Room Services
Bonnie Schnitta -- Sound Sense
Jeff Headbeck -- Headbeck acoustics

 

[Ron Resnick]

What an exciting project, banpuku!

If your long-term plan is to keep those speakers, 25' x 14', or whatever is the golden ratio width for a 25' to 30' long room, seems like a great place to start.

 

[banpuku]

Thanks everyone for your input. The more the merrier. I do plan on keeping my speakers for the foreseeable future.

Wondering if anyone has tried splayed walls and if so, with success or failure. Theoretically, this should help tame some room modes, but also introduce multiple modes that might be harder to conquer.

In my most recent room (23' x 12'), the speaker performed very well. I noticed that too much sound absorption was killing the liveliness and thus, as I removed 1st reflection absorption, the liveliness came back.

What are your thoughts on diffusion on the front wall vs. rear wall? Which is best, assuming there is such a thing as best.

FWIW: at one point, I put concrete cinder blocks staggered against the front wall in such a way that there was no uniformity. The cinder blocks were every which way about 4' high, behind the speakers. This actually was a very nice treatment and helped on many fronts: 1st reflections points on the front wall was a non-issue, bass mode was slightly improved, and diffusion was introduced. I might go back to such a solution, albeit ugly. Then there is the option of placing random sized cardboard boxes staggered in all 3 dimensions (like the photo in the original post). Just thinking out loud.

Please respond with ideas and experiences.

 

[cjf]

Here's what I would do sitting here probably from far,far away but looking at the pictures and diagrams provided.

The red lines are walls and the green boxes are speakers located in this sectioned off room

 

[AMR / iFi audio]

Here's what I would do sitting here probably from far,far away but looking at the pictures and diagrams provided.

The red lines are walls and the green boxes are speakers located in this sectioned off room

Looks like a solid solution. I'm not an construction expert, so I'm just hoping you haven't just blocked the stairwell and it goes other way round

My question to your idea would be - Why don't you see any need to put any speaker in the back of the room?

 

[Tim Link]

Here's an idea that would keep the hvac out of the listening space and give you immediate access to your listening area when you walk down the stairs. This should be a plenty large space being about 16' wide and about 22' long. Nice and symmetrical in the front with doors at the back, away from the speakers. Diffusion in the front of a room this size should be of the type that creates coherent reflections, so polycylincrical diffusors or absorption/reflection diffusors would be advisable. Diffusion which involves various depth wells should be far away from the speakers - at the back of the room if anywhere in there. I agree with John Calder's old post from 2011: https://www.whatsbestforum.com/threads/diffusers-in-early-reflection-zone.3250/#post-51478

 

[Cellcbern]

Regardless of the ultimate dimensions of your listening room, I recommend that you take a look at DHDI's (disruptive with respect to conventional room acoustics) ZR Acoustics panels. They are superior to all conventional room treatments I've experienced, yet combine well with conventional panels (to reduce costs). At a minimum consider them for use on the walls directly behind the speakers and listening position, where they will eliminate reflections without the deadening effect of conventional absorbers. You can use conventional panels if desired (less expensive) on the side walls. With some rooms/systems they obviate the need for bass traps. My own experiences with them are documented on this forum:

Trying the ZR Acoustics Panels

With the pandemic keeping me in the house much more than I'd like, I decided to remove, replace, retry, and validate all of the various tweaks (including acoustical treatments) I've added to my system/listening room over the years. My conclusion as a result of doing this over many months was...

www.whatsbestforum.com

FYI:

https://sonicscoop.com/2012/12/12/delta-h-designs-zr-acoustics-removing-the-room-from-the-room/

From Stereophile:

4. Delta H Design Inc. ZR Acoustics panels: $299 and up
Delta H Design Inc. (DHDI) is an architecture firm and acoustics consultancy in Marina del Rey, California. Their audacious claims for their ZR Acoustics room treatments (patent pending) include that the acoustical panels, which range in thickness from 3/4" to about 4", can control sound in a range from 1Hz all the way up to three octaves above the range of human hearing, ca 160kHz.

Obviously, such claims fly in the face of conventional "quarter-wave theory." Designer-inventor Hanson Hsu says that his mission is to drag architectural acoustics away from the Newtonian billiard-ball model and base it instead on quantum and Mandelbrotian realities. DHDI's technique for radically increasing the number of nonparallel surfaces in a panel "employs fractal and tessellation mathematics hybridized with chaos theory."

Chaos is not anarchy—ie, that the natural universe has no laws. In this context, chaos theory means—as shown by Henri Poincaré's brilliant failure to solve the three-body problem (footnote 1)—that what may appear to be completely random is instead merely bafflingly nonlinear.

DHDI sent me two 24" by 24" by 1.25" ZR Micro panels ($599 each) to go behind my speakers, and three 20" by 40" by 0.75" ZR Sample Rate 8 Bit panels ($299 each) to go between and above the speakers (total: $2095 plus shipping). Hanson Hsu thought those the bare minimum needed to appreciably improve my listening room's sound.

Hsu says that DHDI's design goal is a sound that is "transparent, organic, and musical." In my room, the ZRs accomplished all that in spades. To boil it down to one adjective, the sound was richer. Mobile Fidelity's amazing SACD remastering of Dire Straits' Brothers in Arms converted even a hardened room-treatment agnostic. I was very impressed. A review is in the works. (www.deltahdesign.com)

The Fifth Element #90

As a film title, Quantizing Hanson Hsu might not rank up there with Kissing Jessica Stein, but we work with what we have to work with. Hanson Hsu is the principal designer at Delta H Design, Inc., an acoustics and architecture firm based in Marina del Rey, California. Though he dabbles in some...

www.stereophile.com

See DHDI's client list here: https://deltahdesign.com/portfolio/

 

[cjf]

Looks like a solid solution. I'm not an construction expert, so I'm just hoping you haven't just blocked the stairwell and it goes other way round

My question to your idea would be - Why don't you see any need to put any speaker in the back of the room?

As best I can tell the second picture provided by the OP appears to show the staircase descending down to the right side of the basement. Assuming that my old eyes haven't completely failed me, yet, it also appears to show that given the wall layout i very roughly drew that there would be a solid 4-5ft of hallway remaining along the right side of the room to access the stairs. All of which would be outside of the drawn room.

I think there could be several options for speaker placement in the drawn room. I did my caveman drawing on this silly tablet and using my fat fingers so precision was not on my side at the time. One could do a long wall layout here too given the OP's mention of somewhat nearfield listening.

 

[AMR / iFi audio]

As best I can tell the second picture provided by the OP appears to show the staircase descending down to the right side of the basement. Assuming that my old eyes haven't completely failed me, yet, it also appears to show that given the wall layout i very roughly drew that there would be a solid 4-5ft of hallway remaining along the right side of the room to access the stairs. All of which would be outside of the drawn room.

I had precisely the same assumptions, although I was really curious how will you justify yours. Now I know - there's two of us (at least).

I think there could be several options for speaker placement in the drawn room. I did my caveman drawing on this silly tablet and using my fat fingers so precision was not on my side at the time. One could do a long wall layout here too given the OP's mention of somewhat nearfield listening.

I believe you chose the safest option and I am not much suprised. I was rather interested to know if you somehow took other options into account and made a decision based on some facts that I could not see. I still think that your idea is pretty right.

 

[dcathro]

Hey Pat,

Great looking space that gives you the opportunity to create the perfect listening room.

My only piece of advice would be to find the best acoustic architect to help you - talk to as many people you can to find out who that is.

I got lucky 24 years ago when building a room in London and Billy Woodman from ATC recommended I use "Recording Architecture" (now defunct) and Nick Whittaker. The room they created was the best audio component I have ever used or heard.

Good luck!

 

[Brucemck2]

Two thumbs up for going to a pro at Acoustic Frontiers or similar.

You could just about copy and past LenWhite’s guidance and likely get a pretty good outcome. I am a huge fan of ceiling treatments, with plenty of absorption and diffusers above the listening area.

In prior rooms I found two things useful.

(1) I put cheap speakers in the room and measured the response using Room EQ Wizzard at various alternative speaker and seat positioning points. It’s amazing what a few feet one way or another do in real rooms and provides great guidance on alternatives.

(2) If “wife acceptance factor” does not need to be high, you can buy 2’x2’ RPG absorbers and skyline diffusors and then mount 45 degree wood “hangers” on the back. You then run opposite cut 45 degree wood mounting brackets along the walls at roughly 2.5’ distances apart. That way you can easily move the treatments around until you find a configuration that works well. (In my case I had 4” absorbers running vertically at the corners and along the floor and ceiling junctures, skyline diffusors in between along the front wall, and a smattering for BAD panels and diffusors on the side walls.)

Finally, the giant RPG bass traps work really well. In step #1 up above you can determine where they are most likely to be helpful, and, the frequency range to target.

Good luck.

 

[airbearing]

Hi Banpuku,

don ´t mind, you do not need professionell help if you focus on the mayor issues:
1. use the golden ratio (very important)
2. dampen you walls by LPs or CDs or books - uneven surfaces
3. use ceiling installations as I did in my listening room
4. use the right distance from your speakers (you may move or change the units if possible)

best
eckart

https://audiocirc.com/2014/05/21/a-listening-room/
https://audiocirc.com/2020/02/07/some-15-years-ago/

 

[audioarcher]

Here's an idea that would keep the hvac out of the listening space and give you immediate access to your listening area when you walk down the stairs. This should be a plenty large space being about 16' wide and about 22' long. Nice and symmetrical in the front with doors at the back, away from the speakers. Diffusion in the front of a room this size should be of the type that creates coherent reflections, so polycylincrical diffusors or absorption/reflection diffusors would be advisable. Diffusion which involves various depth wells should be far away from the speakers - at the back of the room if anywhere in there. I agree with John Calder's old post from 2011: https://www.whatsbestforum.com/threads/diffusers-in-early-reflection-zone.3250/#post-51478

I had the same thoughts as Tim, about the location of the room. It's too bad the stairs are located there though.

Ideally the plumbing should have been cast iron instead of pvc. Cast iron is much quieter, and is often used in commercial buildings because of the noise damping. You can insulate the pvc to lower the noise though.

If possible I would build a room within a room to keep out as much noise as possible.

 

[AMR / iFi audio]

(1) I put cheap speakers in the room and measured the response using Room EQ Wizzard at various alternative speaker and seat positioning points. It’s amazing what a few feet one way or another do in real rooms and provides great guidance on alternatives.

This indeed is a very useful tip. I would call it "acoustic scouting".