The Subwoofer Integration Thread (1 Viewer)

[Dave Upton]

Something I hadn't considered is that the MiniDSP can make phase adjustments that are frequency dependent, rather than just making sweeping changes. Is that what you're saying? It completely makes sense that would solve a lot more problems than the internal controls can.

Caveat: This is primarily for 2ch listening, as with subs it isn't as critical if you're using a good room correction tool after miniDSP integration.

Yes, each FIR filter tap can do so. Keep in mind REW primarily generates IIR filters which focus on frequency, so the process for true phase correction without paying for Dirac on the 2x4HD, is to use REW to generate the IIR filters for frequency correction, then adjust delay using the miniDSP, and finally, use RePhase/Acourate/Audiolens to generate FIR filters as needed to correct phase.

rePhase FIR Tool

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I would suggest you start by reading this article - it's short and sweet but will help you understand the filter types (IIR vs FIR): https://www.minidsp.com/applications/dsp-basics/fir-vs-iir-filtering

 

[JohnRice]

I have a significant subwoofer upgrade coming, and I’m busy picking out passages to test the limits. The movies Serenity, Cloverfield and Dredd will be in there. Music from Tool, Dream Theater, Mahler, Saint-Saens, and then if they can reproduce My Favorite Addiction and Bury a Friend by Billie Eilish without rattling, I’ll be impressed. Those last two songs are just about impossible.

Any suggestions?

 

[Dave Upton]

I’m busy picking out passages to test the limits. The movies Serenity, Cloverfield and Dredd will be in there. Music from Tool, Dream Theater, Mahler, Saint-Saens, and then if they can reproduce My Favorite Addiction and Bury a Friend by Billie Eilish without rattling, I’ll be impressed. Those last two songs are just about impossible.

Any suggestions?

Here are some of my favorites. You already nailed it with Billy - her recordings are extremely bass rich.

Bassnectar: "Science Fiction" from Into the Sun

Bassnectar & The Glitch Mob - Paracosm

The Glitch Mob - Drink The Sea

Birds of Paradise - Soulgasm

Daft Punk (Tron Legacy Soundtrack) - Disc Wars

Boards of Canada: "You Could Feel The Sky" from Geogaddi

 

[John Dirk]

This sounds like you're dealing with the dominant axial nulls in your room. One way to save yourself a little time, is to use a tool like amroc to determine where the nulls are worst in your space. You can then try to put your subs in "good" spots:

Thanks Dave! Nice tool. It shows my main problem areas as being the ceiling and middle space, two areas I obviously have no control over. Also possibly complicating things is the odd shape of my room. See crude representation. Not perfect by a long stretch but it's "what I got".

 

[Dave Upton]

Since your room is not a perfect rectangle, that does complicate things somewhat, but I can tell immediately some challenges with your room.

1) You're using too much of the front wall for screen. If your speakers are close to a boundary (wall) you're hurting their performance quite a lot. I know nobody wants to hear this, but going down in screen size or going with an AT screen could substantially improve your audio.
2) I modeled your room as a rectangle, just to look for "safe spots". It appears that you are doing pretty well in your current spot, but would benefit a lot from some bass trapping. This is difficult with how much of the room you're using for screen, but I'd put corner traps in the front left and right walls at a minimum, if I were you.

Here's a picture of that in my room (same width as yours). I have 2 bass traps in each front corner. 1 GIK Tri-Trap, and 1 MSR Acoustics SpringTrap:

 

[John Dirk]

Since your room is not a perfect rectangle, that does complicate things somewhat, but I can tell immediately some challenges with your room.

1) You're using too much of the front wall for screen. If your speakers are close to a boundary (wall) you're hurting their performance quite a lot. I know nobody wants to hear this, but going down in screen size or going with an AT screen could substantially improve your audio.
2) I modeled your room as a rectangle, just to look for "safe spots". It appears that you are doing pretty well in your current spot, but would benefit a lot from some bass trapping. This is difficult with how much of the room you're using for screen, but I'd put corner traps in the front left and right walls at a minimum, if I were you.

Here's a picture of that in my room (same width as yours). I have 2 bass traps in each front corner. 1 GIK Tri-Trap, and 1 MSR Acoustics SpringTrap:

View attachment 96243

Yep. Your suggestions are pretty much in line with what I expected and underscore @Sam Posten 's comments from the February podcast. There's always a tradeoff between optimal performance and real-world conditions. In my specific case it looks like it comes down to whether I want to optimize audio or video.

I knew the speakers would be a challenge when I purchased them due to their size and worked hard to get them placed in a way that allowed me to retain most of my screen area. Fortunately though, my projector supports lens memory so I can quickly switch between this setup and a smaller screen area for test purposes. I'll have to do that and decide if the performance improvements are worth it to me.

Thanks for recommending GIK Acoustics. Turns out they're located right here in ATL, about 30 minutes from me. I'll definitely be reaching out.

 

[JohnRice]

Since your room is not a perfect rectangle, that does complicate things somewhat, but I can tell immediately some challenges with your room.

1) You're using too much of the front wall for screen. If your speakers are close to a boundary (wall) you're hurting their performance quite a lot. I know nobody wants to hear this, but going down in screen size or going with an AT screen could substantially improve your audio.
2) I modeled your room as a rectangle, just to look for "safe spots". It appears that you are doing pretty well in your current spot, but would benefit a lot from some bass trapping. This is difficult with how much of the room you're using for screen, but I'd put corner traps in the front left and right walls at a minimum, if I were you.

Here's a picture of that in my room (same width as yours). I have 2 bass traps in each front corner. 1 GIK Tri-Trap, and 1 MSR Acoustics SpringTrap:

View attachment 96243

Dave, slightly off-topic question. Is your center speaker a pre-production unit?

 

[John Dirk]

Dave, slightly off-topic question. Is your center speaker a pre-production unit?

I can answer that one on Dave's behalf. "Yes."

 

[Dave Upton]

I can answer that one on Dave's behalf. "Yes."

Yeah, my center was an early version of the Marquis XD. Bill gave me the opportunity to get the new drivers and I couldn’t say no

 

[JohnRice]

The subwoofer upgrade is very close. It has arrived in Denver and just needs to travel the final 60-70 miles.

Hopefully tomorrow.

 

[JohnRice]

And today... it will be tomorrow. Gives me an excuse to take an extra day off, depending on when they're delivered.

 

[John Dirk]

I just got on GIK Acoustics' schedule for a room evaluation. Pretty straightforward process. You just describe your room and it's intended use, upload some photos [they tell you what is needed] and wait to hear back from them with a recommended plan. @JohnRice , if this is something you think might interest you I would suggest contacting them sooner than later as they're on a 8 - 10 week backlog for product orders.

 

[JohnRice]

I just got on GIK Acoustics' schedule for a room evaluation. Pretty straightforward process. You just describe your room and it's intended use, upload some photos [they tell you what is needed] and wait to hear back from them with a recommended plan. @JohnRice , if this is something you think might interest you I would suggest contacting them sooner than later as they're on a 8 - 10 week backlog for product orders.

That looks really interesting. Fortunately, my HT room seems to be good where those kinds of problems are involved.
The living room has bigger issues. Actually, the main thing in my HT is I need to hunt down and secure rattles. Various things around the room and walls that resonate at different frequencies at theatrical levels.

 

[John Dirk]

And today... it will be tomorrow. Gives me an excuse to take an extra day off, depending on when they're delivered.

Pro tip - Offer a little incentive to the carrier and they may help you get them where they need to be inside your house.

 

[DaveF]

How long did fulfillment take after order? I’ve got something ordered but awaiting order shipment info. Don’t know if there’s a wait due to pandemic problems. (I haven’t gotten to the point of contacting to get info, yet, since I’m not in a hurry.)

 

[JohnRice]

How long did fulfillment take after order? I’ve got something ordered but awaiting order shipment info. Don’t know if there’s a wait due to pandemic problems. (I haven’t gotten to the point of contacting to get info, yet, since I’m not in a hurry.)

What did you order? Is it in stock?

 

[DaveF]

What did you order? Is it in stock?

I think it’s in stock. I’ll post about it when I get and can do photos and such. (It’s not dual Ultras or anything crazy like that, but it should be nice)

I’ll check on the status this Friday if I’ve not gotten shipping info.

 

[John Dirk]

I think it’s in stock. I’ll post about it when I get and can do photos and such. (It’s not dual Ultras or anything crazy like that, but it should be nice)

I’ll check on the status this Friday if I’ve not gotten shipping info.

That's odd from SVS. They're usually right on top of such things. I suspect a carrier issue.

 

[DaveF]

That's odd from SVS. They're usually right on top of such things. I suspect a carrier issue.

I'll followup tomorrow. I'm not particuarly concerned, but something might have fallen in the gap, as it's been a week without fulfillment or shipping info.

 

[John Dirk]

Pro tip - Offer a little incentive to the carrier and they may help you get them where they need to be inside your house.

Any update???