Here’s my mock-up of a 12x16’ room.
The spacing from back and side wall to the center of the speaker is 2’6", forgot to add it on the sketch.
Here’s my mock-up of a 12x16’ room.
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If you angled tannoys like that your ears would bleed.
What do you guys think for the angle and spacing? This is to scale with the Focal Chora 826 speakers and a chair.
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That’s how they said to angle them for the ones I had.
All you can do is try it out, looks great to me as a starting point. I like the tweeters to the outside of shoulder thing it generally works well.
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Hi, Regading dimensions, a good guideline is to ensure height + width = length, to reduce standing waves. Given the fixed height of 8 feet, good dimensions would be, 14 feet wide and 22 feet long. You can apply this ratio with the space you are able to allocate. The golden ratio works well for sound room dimensions
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With that chair nearly in the center of the room, you’ll have a good chance of sitting right at a bass null for many bass frequencies. But there is some good space in the back, so you can play with that.
Just like speaker position and toe-in for your specific speakers can’t be fixed by a floor plan in advance. I would recommend playing with positioning and listening after getting the basics right. There are a thousand speaker positioning guides on the web, but I’d recommend spending the time for:
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I would put studs on the backwall with fiber glass in it. Then put top to bottom high mass loaded vinyl over the studs, sealed 360 degrees around the wall. You van experiment by making partitions with different depths.these will be your bass traps tuned at different low frequencies. Then add some loose absorption over it, but be sure the limp vinyl membrane can move (vibrate) freely.
Later you can treat side and front walls with absorption materials as is needed.
But without measurements and calculations this has just as much chance to remove energy from the wrong frequencies (where there is already a trough) as it has removing it from the right frequencies (where there are peaks)
Good point, but broad band bass traps don’t suck out bass energie, they avoid ringing and reflections and especially at the back wall where the sound plane hits the wall in a perpendicular way, avoiding low frequency reflection, that also causes nulls and extremes, from that wall to the listening chair. There will probably be enough bass left.
But still, you have a good point, without much knowledge about the behavior of this room it is a lot of guessing of how it will be in reality.
True, they might not end up being that precisely tuned. Though for actual bass below 100 Hz or even lower, they must be huge as well. If the room is not very large, like in this case, it becomes a competition between the trap size and seating distance to back wall 
In the end, like I said before, I’d involve professionals (which e.g. GIK offers online without crazy costs) and perform measurements to be able to address the actual problems.
And active or diaphragm bass traps for the actual bass issues instead of cutting room size by half
I have a rather large room and the only actual bass issue is a room mode below 40Hz. It doesn’t bother me much because outside of electronics or organs nothing much happens there, but it would be a nightmare (more like impossible) trying to address this with passive solutions
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40 Hz is difficult to treat, you need some square meters of membrane damping.
I had troubles with a 71 Hz resonance, an oblque one going from the speakers bottom frontwall to the ceiling backwall, but I was never very sure about that one. 71 Hz didn’t fit my room dimensions but could only be generated by the roommodes themselves. I put two selfmade membrane absorbers on top of the cupboard in the ceiling corners and they help! The increase in level at 71 Hz is still there but less and doesn’t annoy anymore plus the note doesn’t ring anymore.
But building them was a hell of a job and they couldn’t be too heavy so I had to use a lot of expensive birch ply supported by some aluminum.
But they do work! Maybe I was also a bit lucky. I built the ones you find a diy drawing of at acoustic fields.
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If I ever decide to do something about it, it’s most likely going to be with Roon DSP (I probably listen to one vinyl record per year where it’s even an issue, so…).
To address analog sources and if one doesn’t fancy the challenge of an interesting DIY project, I would nowadays simply go active
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I’ve enlisted the help of a family member who is a general contractor (originally carpenter). The current plan is for a room 7’ ceiling, 12’ width, and 19’ length. Wood stud walls and mineral wool insulation between all walls and the ceiling joists, then 2 layers of 1/2 drywall, with caulking between layers to ensure a tight seal. When the walls are open I’ll install several dedicated 20A receptacles, and a large conduit for future wall-mounted TV cables (and an outlet by it for the TV). I plan on also adding LED pancake lights, a front/rear zone, with a dimmer. The back wall where the speakers will be is a cinderblock wall, but I’ll be adding a wood frame wall onto it to allow for wiring.
That is definitely a very innovative “thing”. I also thought about this devices as a way to reduce low frequency noise going through a wall by placing them against the concerning wall, as a last means to treat noise problems.
Here in The Netherlands real estate developers even use drywall in new buildings between two apartments because in dB(A), where only mids and highs count, these cheap wall are good enough on paper, but with music and cinema they are just paper.
Drywall can be built right, but yeah. In Germany, the officially used DIN norm is outdated and badly insufficient, and most new buildings actually conform to a newer and much better one, but guaranteeing the worse one is the only one necessary, so it’s a nightmare to get anyone to address a noise bridge.
When I moved to a new apartment, SQ and neighbor isolation was my top priority Not quite perfect, but I got close
It seems that the availability of building materials in the USA versus Germany or other countries is vastly different, to the extent that my construction method is a good value, but might be unrealistic or more expensive than a superior method outside the USA. Here drywall is the go-to.
That active bass trap looks excellent, however at combined $4,000 for two, it’s prohibitively expensive in my case (more than the whole room costs). There’s always damping and Roon EQ to correct the room.
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Will you plug in your equipment into the same power line or will you have a separate power line for you music equipment separate from the lights?
Yeah but damping does nothing in bass, the wave lengths are too long. Apart from a large room, the only room acoustic solution to bass modes is something like this or the tuned diaphragm traps. Measuring the room and using DSP in Roon is certainly the most sensible option if you don’t need a solution for analog sources. (Try the HAF filter thread)
The plan is to have a dedicated circuit that’s just for the equipment, and another for the lighting and other general-purpose outlets. Also one for a future wall mounted TV, with a large conduit for data cabling. Cat6 cables will be run to 1-2 jacks for network connection. It’s worth noting I’m an electrician and also the panel is 10’ from the room, so adding circuits doesn’t take much wire and there’s no install cost.
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