How do you EQ / treat this room?

[PK1]

Its not a job, its an adventure...

Yeah It’s a ton of fun too. It’s the research about everything that takes a of time. For example, if I want to apply EQ and time delays, do I need all the apps and plugins that you highlighted above, or would one (or two) of them do it and everything else is extra features?

 

[PK1]

Why doesn't the OP simply rotate his system 90 degrees so that the loudspeakers are set up in front of the longer 23' left wall? This would allow the speakers to operate in an acoustically symmetrical space with regards to the front and sidewall boundaries, avoiding large scale differences between the left and right loudspeakers' low frequency response curves...

In the schematic I have only shown the audio set up, not everything else. This is also a game room with a shuffle board, air hockey, foosball, etc, and the TV is mounted in between where the speakers are. I’d prefer keeping the set up this way because I simply cannot put the other items in different locations while ensuring functionality of the room (you also need walking space to access other parts of the house through this room), aesthetics, etc. This is why in my first post I had mentioned that changing the layout wasn’t an option.

 

[VinceHoffman]

Well I'll make a reasonably educated guess that the green line in your response graph is the left speaker stuck in the corner @PK1?

 

[PK1]

Well I'll make a reasonably educated guess that the green line in your response graph is the left speaker stuck in the corner @PK1?

Correct. Since the legend wasn’t showing I had pointed this out in the text above the graph. Obvious difference between the left and right speakers in the lower frequency range.

 

[VinceHoffman]

Well no

Correct. Since the legend wasn’t showing I had pointed this out in the text above the graph. Obvious difference between the left and right speakers in the lower frequency range.

Well as others have suggested, the nested pair of suck-outs just above and below 100Hz are gonna be SBIR from the nearby front wall and side wall boundaries. EQ can't fix this. To address this problem you either need to move the loudspeaker 5+ feet off the wall boundaries or acoustically treat the adjacent room boundaries causing the problematic low frequency reflection. The latter would require a substantial bass trap on each of the wall surfaces immediately to the side and rear of the left speaker.

You can definitively prove this for free! Stack a couple of unopened bags of pink fluffy fiberglass joist insulation at the wall boundaries immediately opposite the speaker position, then re-measure with REW. These make-shift bass traps won't perfectly address the problem (the insulation is packed too tightly in the bags) but you will see a clear measured reduction in the suck-out. Return the unopened bags to the builder's supply store you bought them from and either buy or DIY the real bass traps capable of efficient absorption down to 90Hz.

In my (symmetrical) room I successfully addressed the sidewall SBIR issue I had at the same frequency you are dealing with (my speakers are 3' off the sidewalls) with a pair of 13"D x 6'H ASC Tube Traps. There are (much) cheaper commercially made solutions available from companies like GIK.

 

[ddude003]

I agree with @VinceHoffman that you should try and address some your room issues with acoustic treatments first... You can't just EQ boost your way out of those dips below the Schroeder frequency... You can however flatten the peaks around them... And while we are on the subject of room modes it might be fun to have a look at https://amcoustics.com/tools/amroc if you haven't looked at REWs Room Sim, now might be a good time...

The way to go is to do what you can to your room with acoustic treatments and then apply digital room correction...

And watch a master class in digital room correction...

I'll answer your questions a little later today after I get a few things done around here...

 

[PK1]

@VinceHoffman that’s quite the set up you have there! The material that @JStewart had posted earlier in this thread was very educational for me and made it clear that SBIR can’t be fixed with EQ, which makes a ton of sense now that I know why. I still applied EQ filters to align the response to the Harman curve as an experiment, and it actually made a difference by taking some of the “boominess” away, making the music more pleasant to listen to. I have subwoofers located right next to each speaker (on the inside), and through adjusting crossovers and gain, the right sub has entirely disappeared and has “snapped on” to the right speaker. With the same settings on the left speaker, however, I can sometimes hear the left sub, especially the lower frequencies. I’m assuming this has to do location of it and SBIR. I’ll be looking at some “minimal” and strategic room correction as my better half isn’t overly excited about looking at room correction material in that room! In the meanwhile I’ll be playing with the settings on the left sub to see if I can make it a little better.

@ddude003 thanks for posting the material. I listened to the first few minutes of the video and it seems to be very comprehensive. I’ll be watching the whole thing when I find a couple of hours later tonight or tomorrow.

 

[ddude003]

So, lets see if I can catch up... If your better half does not like the idea of traps and absorbers scattered about maybe she would be happier with some potted plants... Stands of bamboo or other things that are big and leafy... Pots of dirt or sand with live or dried bamboo or other dried arrangements... Especially placed around the corner speaker and where may be its first reflection point along that left wall...

Next is those plugins... In order to get your hooks into the MacOS sound system you need BlackHole as it a router for all things MacOS audio... And you need a AU plugin host... Then you can use the Apple AUNBandEQ you are using, if you use that HangLoose host you can split your left and right channels for gain and eq which it doesn't seem SoundSource can't do... You don't "need" a convolver although it will do a better job for Room Correction than a simple several band EQ... I use the HangLoose Convolver with FIR filters for Digital Room Correction and layer some other plugin EQs to add a little flavor to taste...

If you are looking for another plugin EQ that may be better than the Apple AUNBandEQ here are a few to look into...
Here are the best FREE EQ Plugins available in 2023:

TDR Nova
TDR VOS SlickEQ
MEqualizer
Cockos ReaEQ
lkjb QRange
lkjb Luftikus
Blue Cat Triple EQ
Fuse Audio RS-W2395C
PTEq-X
Rare “BPB Edition”
Warmy EP1A Tube EQ V2
Sonimus SonEQ
Voxengo Marvel GEQ
EQ560
Blindfold EQ
DDMF ColourEQ

Hope that helps...

 

[VinceHoffman]

So, lets see if I can catch up... If your better half does not like the idea of traps and absorbers scattered about maybe she would be happier with some potted plants... Stands of bamboo or other things that are big and leafy... Pots of dirt or sand with live or dried bamboo or other dried arrangements... Especially placed around the corner speaker and where may be its first reflection point along that left wall...
...

Not to be that guy @ddude003, but the above potted plant suggestions- live or dead -will do next to nothing at the problematic frequencies the OP is dealing with.

 

[ddude003]

@VinceHoffman, Next to nothing is better than nothing, a bare wall... Its not just the plants, its the dirt, sand or even Activated Carbon in the pots...

 

[VinceHoffman]

Again, not to be that guy @ddude003, but you are propagating "audiophile myths" that no accredited acoustics professional would support.

 

[ddude003]

Again, not to be that guy @ddude003, but you are propagating "audiophile myths" that no accredited acoustics professional would support.

I guess you haven't kept up on the science of the middle ages... Ceramic pots can be thought of and used as Helmholtz resonators... And what about the acoustic properties of bamboo... Maybe you can tell me why some speaker manufactures use Activated Carbon in the speaker cabinets... I don't see the point of arguing... Maybe you can tell me why you have cable elevators in the photo of your room...

 

[JStewart]

@PK1 , to address the low bass issue on the left speaker, is moving the speakers closer to the wall an option? It will push the problematic cancellation frequency higher for the front wall reflection and perhaps it won’t be as severe if your speaker is not as omnidirectional at the frequency it then lands on. In any case, the front wall/side wall distances won’t be the same any longer. Our forum member @DanDan is a recording engineer, I believe, and a proponent of having speakers against the front wall. Perhaps if he sees this thread he may have a suggestion.

You might also try the subs to the outside of the speakers if you can, but keep the speaker baffle even with or more towards you than the sub baffle. You should definitely need some PEQ on the sub frequencies to lower peaks if try the subs on the outside.

Unfortunately, while there is some known physics involved, things don’t always work as one might expect, especially in a room that is not a sealed rectangle with furnishings in it. Experimenting is time consuming, but also the only way to know.

@VinceHoffman that’s quite the set up you have there!

There’s more photos of it around here. Simply to die for. No doubt sounds as amazing as it looks.

 

[VinceHoffman]

I guess you haven't kept up on the science of the middle ages... Ceramic pots can be thought of and used as Helmholtz resonators... And what about the acoustic properties of bamboo... Maybe you can tell me why some speaker manufactures use Activated Carbon in the speaker cabinets... I don't see the point of arguing... Maybe you can tell me why you have cable elevators in the photo of your room...

No open top plant pot (made from ceramic, plastic, or anything else you can dream up can be a Helmholtz resonator @ddude003. But a ceramic, glass, steel, etc. bottle where the bottle volume and small port opening are tuned to the desired resonant frequency can be. Of course sticking a few real or fake plant stems in the small port mouth of your Helmholtz jar would ruin its tuning and function as a resonant trap. And even if we just stuck to the tuned bottles themselves we'd need a bookshelf full of them on each of the problematic walls in order to achieve a useful degree of absorption of that offending frequency associated with the SBIR suck-out.

As for those cable elevators- For the portion of the low level interconnect cable runs to my active loudspeakers which runs in parallel with the power cords to each speaker, the signal cables are strung across $.50ea 6" tall plastic stands (used to neatly space out steel rebar in poured concrete construction)... This ensures that the low level signal cable doesn't end up with 60Hz induced hum from the high current AC power cable running in parallel beneath it.

 

[VinceHoffman]

Getting back on track, if you are willing to lay out the dough, a pair of the RPG Plate 2.0 bass traps, one on each of the adjacent wall surfaces will get the job done in a pretty stealthy fashion @PK1. The Modex Plate VPR bass traps are only 4" deep. They are available upholstered in any Guilford of Maine acoustic fabric color allowing you to match your room's wall or trim paint color. Not completely invisible but not visually objectionable either- certainly when compared to other 12+ inch depth bass trap solutions which are effective to these frequencies...

 

[PK1]

@ddude003 thanks for the list of apps and plugins, very helpful. So sounds like Blackhole effectively does what SoundSource does but you said it also needs a plugin host for AU. Is this something that is within the app or a separate thing I need to install? Also, is another way of thinking about this that with Blackhole and Hangloose I could do most of my room corrections and would only need EQ (e.g. AUNbandEQ) as a “flavor” only?
One major flaw of SoundSource is that id doesn’t load output files from REW automatically into AUNBandEQ, you have to manually enter each parameter (I verified this with SoundSource directly). There are workarounds and scripts online but I don’t want to mess with that, so if Blackhole + Hangloose (or Blackhole + AU host + AUNbandEQ) will give me a more user friendly result I’ll switch to that.

@JStewart the speaker placement guide that you had listed earlier also talked about putting the speakers against the wall as the next best thing compared to building them into the wall directly. I always thought (read) that doing so will come at the expense of imaging That said, I did try it briefly (speakers only) and as expected got more bass so I need to tweak things. I’ll need time to move things around to experiment. One other thing that isn’t shown in the diagram is that in the left corner I have my equipment cabinet which is a pain to move around. Here are a couple of pictures to show the left and right arrangement. Yet another restriction is that I have a closet door next to the right speakers so I need to keep that space open. Moving the subs to the outside means that the main speakers will be too close to one another relative to my listening position. Telling you, first world problems!

@VinceHoffman have to agree that those RPG plates do look decent - but at a cost! In the above pictures you’ll see wall space limitations so I may need something custom-made or DIY to make it fit and look good.

 

[PK1]

And the whole set up for good measure:

 

[ddude003]

Here is an example of using Blackhole, the HangLoose Plugin Host and a left and right channel with two instances of Apple's AUNBandEQ... I don't think it is any easier to load your parameters, although you can adjust gain and EQ on the individual left and right channels... I don't think you can do this with SoundSource...

Blackhole is free, your Apple plugins are free and the HangLoose Plugin Host is $20... It also comes included if you get their Convolver...
You can use most any EQ or other AU plugins, some free ones I listed above... This is one solution...

Another would be to do this same setup and instead of the AUNBandEQ use one of the many free or otherwise EQs on the market...

Another solution would be to use Blackhole, the HangLoose Plugin Host and the HangLoose Convolver, or another convolver... The trick here is you will have to create FIR filters for your room correction... You can see from the videos that it may be no simple task to create your own FIR filters...

 

[ddude003]

Here is the the HangLoose Host + HangLoose Convolver running one of my Room Correction FIR filters...

You can easily add other plugin(s) between the HLConvolver and the Audio Output... In my case its usually another, so many choices, colorful EQ... And oh, once you get Blackhole installed and setup you don't really ever see it again...

 

[ddude003]

And for fun and completeness there is this example with two plugins, Convolution Room Correction and Dynamic EQ...

 

[PK1]

Very clear, thanks for posting. I still have to do some physical room correction or do some repositioning of speakers but for digital correction I’ll do what you’re doing.

SoundSource doesn’t do individual channels and also doesn’t automatically load REW filters in AUNbandEQ, although apparently does through other plugins. It is a good product for what it’s supposed to be and their customer service is great (they are very responsive and customer friendly) so for more simple EQ corrections it’s a solid solution, but for tinkering and experimenting it has its limitations.

 

[ddude003]

No open top plant pot (made from ceramic, plastic, or anything else you can dream up can be a Helmholtz resonator @ddude003. But a ceramic, glass, steel, etc. bottle where the bottle volume and small port opening are tuned to the desired resonant frequency can be. Of course sticking a few real or fake plant stems in the small port mouth of your Helmholtz jar would ruin its tuning and function as a resonant trap. And even if we just stuck to the tuned bottles themselves we'd need a bookshelf full of them on each of the problematic walls in order to achieve a useful degree of absorption of that offending frequency associated with the SBIR suck-out.

As for those cable elevators- For the portion of the low level interconnect cable runs to my active loudspeakers which runs in parallel with the power cords to each speaker, the signal cables are strung across $.50ea 6" tall plastic stands (used to neatly space out steel rebar in poured concrete construction)... This ensures that the low level signal cable doesn't end up with 60Hz induced hum from the high current AC power cable running in parallel beneath it.

You can take your straw man and stick him in that plastic pot, add a few plastic straws and a miniature umbrella, place it on that zero point energy grid in your basement and surround him with a few empty beer and wine bottles and measure him for some dynamo hum...

I don't appreciate you taking what I said and twisting it about... And I don't take your accusations of my propagating "audiophile myths" that no accredited acoustics professional would support without pushing you back... In fact, anything you place in an acoustic environment will change the acoustics...

 

[DanDan]

Quote PK1 I always thought (read) that doing so will come at the expense of imaging

If that were true then the World's Top Recording Studios with Flush Mounted Monitors must have poor imaging.
Acoustic Treatment is very effective at improving the sound from speakers to ear.
Location is also very influential and as mentioned earlier I do advocate try the speakers almost touching the Front Wall. I use masking tape to prevent them scratching..... Even with Subs and Satellites I reckon it still worth trying Kissing the Front Wall.