AudioCircle
Industry Circles => GR Research => Topic started by: Early B. on 28 Sep 2017, 04:11 am
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Has anyone experimented with placing a third sub in the back of the room? I'm thinking maybe a quasi-swarm that consists of a single sealed servo sub to help even out the response.
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Has anyone experimented with placing a third sub in the back of the room? I'm thinking maybe a quasi-swarm that consists of a single sealed servo sub to help even out the response.
Early B,
Another GR Research user did and his results are here: http://www.audiocircle.com/index.php?topic=150042.0
Lots of details to learn and understand in that thread.
So yes, that's now a multisub setup.
Best,
Anand.
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Thanks for your post. I've been contemplating the same thing.
I only have a few positions that would work due to the system being in my living room and I don't want it out in the open.
Paralysis by analysis so far. Thanks for the link... will review.
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Yes using one. I run it out of phase to main subs. Placed 4' behind me.
charles
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I think I'll conduct an experiment this evening and report back. I have a third sub in the back corner of the room that's used exclusively for home theater. All I would need is a long run of RCA cable to hook it up to my 2-channel system. It might be interesting. I'll play around with the phase adjustment.
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Yes using one. I run it out of phase to main subs. Placed 4' behind me.
Hey -- give us all of the juicy details.
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Danny has routinely recommend a sub at the back of the room run out of phase. If I remember correctly that is how he set up his rooms at shows.
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Hey -- give us all of the juicy details.
First off using Rethm Saadhana full range speakers. www.rethm.com. Have an older Sunfire sub. To set up by ear put on some bass heavy music. With volume control on lowest setting sit in chair then adj. volume until you HEAR the rear sub. Then turn down until it is not prominent meaning you cannot tell where sub is.
charles
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Danny has routinely recommend a sub at the back of the room run out of phase. If I remember correctly that is how he set up his rooms at shows.
Yes, I believe he uses a pair of sealed sW12 -04's, one in each rear corner. Also beleive they are run out of phase from the front subs and typically at a much lower volume
Some sealed cabinets are "on the list : :lol:
jay
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Yes, we run them in the corners of the back of the room, but a single unit can also be very effective.
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OK... sounds easy. Extra sub- check! Extra Amp- check!.
Now all I have to do is figure how to set up the Berhinger 2496... not so easy, for me anyway.
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Yes, we run them in the corners of the back of the room, but a single unit can also be very effective.
stereo or mono signal input for the subs at the back.
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I think I'll conduct an experiment this evening and report back. I have a third sub in the back corner of the room that's used exclusively for home theater. All I would need is a long run of RCA cable to hook it up to my 2-channel system. It might be interesting. I'll play around with the phase adjustment.
OK, I just performed a quick experiment and here's my assessment: :o :o :o 8) :o :o :o
Gut wrenching, bowel busting, ball tingling bass!
I started with some very bass heavy George Duke tracks. The third sub took the bass to a completely different level. It's crazy, man. I like. A lot.
Then I slowed it down and put on the latest Lizz Wright CD where the first track has some great bass. Incredible! I set the phase level where I liked it. And I really like how I can easily dial in just how much or how little bass I want.
Bottom line -- a free tweak that's gonna remain part of my two-channel system.
FWIW -- I'm using a bastardized AV123 sub (remember those guys?). Well, actually, I'm only using the gorgeous cabinet. I upgraded the amp and the 15" woofer a few years ago. I believe Danny has a thread on here somewhere where he re-built the cabinet I have, but I won't go down that road.
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stereo or mono signal input for the subs at the back.
If you have a pair up front running in stereo and have a pair for the rear, runthe rears in stereo as well. If you're going to use a single inthe rear, run it in mono
jay
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Is there a way to hook up the third sub to both the HT receiver and 2-channel preamp? A Y-adapter doesn't work -- you'll get feedback. Right now, I have to manually plug and unplug cables. Of course, both systems will NEVER be on at the same time.
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One more question --
If I wanted a better quality sound from the third sub (or does it matter so much?), would this cost-effective, sealed servo sub be all I'd need: http://www.rythmikaudio.com/L12.html
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Is there a way to hook up the third sub to both the HT receiver and 2-channel preamp? A Y-adapter doesn't work -- you'll get feedback. Right now, I have to manually plug and unplug cables. Of course, both systems will NEVER be on at the same time.
It depends on the amp. If it has two pairs of inputs like an A370PEQ3 you would use one of the input pairs for HT and the other pair for 2-channel. I've done that before and it worked just fine.
One more question --
If I wanted a better quality sound from the third sub (or does it matter so much?), would this cost-effective, sealed servo sub be all I'd need: http://www.rythmikaudio.com/L12.html
More expensive than the L12 but I'd go with an F12G. This would also give you the A370PEQ3 amp so you'd have the two sets of inputs you'd need for both HT and 2-channel hookup
Mike
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It depends on the amp. If it has two pairs of inputs like an A370PEQ3 you would use one of the input pairs for HT and the other pair for 2-channel. I've done that before and it worked just fine.
I have the Dayton Audio 230 subwoofer amp: https://www.parts-express.com/dayton-audio-sa230-230w-subwoofer-amplifier--300-813
Works great. Very inexpensive and better than most plate amps (Parts Express has refurbished ones for $125 shipped)
This amp has a set of inputs and an LFE. I'd have to run a 35 ft. of RCA cable to make it work, but doable.
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The LFE input would be for the HT
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The LFE input would be for the HT
Correct. That's how I have it hooked up now. I just ordered a long RCA cable. Gonna hook it up this weekend.
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BACK AGAIN....
My attempt to use my HT sub was a temporary solution two years ago, but it didn't last very long due to connectivity issues. Nevertheless, it convinced me that a rear sub for my 2-channel system was in my future. Well, the future is now.
I finally assembled a third dual OB servo sub and placed it a couple of feet behind the listening position near the rear wall. With a low crossover setting and set out of phase, it blends seamlessly with the front subs. However, I only spent 15 minutes listening and tweaking, but it sounds great so far, as expected. I'll resume listening and tweaking after Christmas when I have more time. No pics worth posting yet.
What I said earlier in this thread when I was using my HT sub still applies, but cleaner and better: "Gut wrenching, bowel busting, ball tingling bass!"
I placed an order for an amp box from mlundy57. Once it arrives, I'll clean up the wiring with Neutrik connectors.
P.S. -- the WAF Police hasn't done a drive-by yet. Let's hope I don't get a speeding ticket.
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If you follow the teachings of Earl Geddes, Floyd Toole, and our own Duke LeJeune you'll discover the concept of using a subwoofer "swarm" to tame inherent in-room bass peaks/dips. In his seminal work "Sound Reproduction" Toole explains how bass behaves like waves and that those waves can double up, cancel, etc. due to the room size and shape (like waves in a shallow tub). Geddes points out that physical problems can best (only) be cured via physical means (not DSP). LeJeune sells a well received swarm system. The concept works with 3 but more frequently 4 subs located near corners.
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If you follow the teachings of Earl Geddes, Floyd Toole, and our own Duke LeJeune you'll discover the concept of using a subwoofer "swarm" to tame inherent in-room bass peaks/dips. In his seminal work "Sound Reproduction" Toole explains how bass behaves like waves and that those waves can double up, cancel, etc. due to the room size and shape (like waves in a shallow tub). Geddes points out that physical problems can best (only) be cured via physical means (not DSP). LeJeune sells a well received swarm system. The concept works with 3 but more frequently 4 subs located near corners.
I'm familiar with their work; their research is what prompted me to try a third sub. Since open baffle subs load the room differently than typical sealed subs, it would be interesting to see how an OB swarm would perform. I'd love to add a fourth sub, but my room configuration won't allow for it.
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The number of subs required to smooth out the bass responds has a lot to do with the number and placement of different seating positions. A listening room with only one seat is much different than a room with multiple rows of seats. The more seats, the more subs needed to get good bass at all positions. It’s another case of one size doesn’t fit all.
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Has anyone had luck using Room Correction to integrate multiple subwoofers? Doing it manually can be quite a chore.
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Yes, I did it for a customer with 2 front and 2 rear subs with a DSP crossover using time delay. Integrated very well.
Try using Room EQ Wizard and calibrated mic for measurements at the listening position. Start with one sub at a time. Even a RadioShack SPL meter will work with a warble tone CD.
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Has anyone had luck using Room Correction to integrate multiple subwoofers? Doing it manually can be quite a chore.
Yeah, if someone has a youtube video link or simple instructions for the non-tech savvy on how to integrate multiple subs, please provide it here. I don't know where to start, so I'm relying solely on my ears.
One of my recommendations to Danny was to do a Tuesday Tech Talk where he actually goes into someone's home and shows us how to conduct measurements, recommends treatment options, makes speaker placement suggestions, and sets up the open baffle subs properly.
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From HAL,
"Try using Room EQ Wizard and calibrated mic for measurements at the listening position. Start with one sub at a time. Even a Radio Shack SPL meter will work with a warble tone CD."
Thanks HAL,
I have 2 custom floor standing monitors Danny just re-worked for me. They are built with down firing 12" sealed servo subs built in to the bases. I have 2 more 12" sealed boxes left over from an older Super V project. I will build out the other 2 subs in the next month and start working on a true "Servo Swarm". :thumb:
I use a Lyngdorf Digital amp so running Room Perfect is in the plan. I have always considered setting up the Swarm properly daunting. Honestly I never broke it down to setting up 1 sub at a time. I can wrap my head around that. I have always had issues trying to get the phase perfect in outboard subs. I suppose Room EQ wizzard might help with that. I have a good Mic and stand (came with the Lyngdorf TDAI 270). but i think I need a good outboard sound card for the program to work properly. My Dell laptops are not set up for high end audio measuring. :|
From CujoBob,
"Has anyone had luck using Room Correction to integrate multiple subwoofers? Doing it manually can be quite a chore.
Bob, The DSP can do miracles on the room, but I don't think there is any shortcut to proper placement, phase, PEQ settings etc. Think I have to spend a Saturday doing measurements and adjusting subs. Then run Room Perfect to lock it in.
Some day, I hope someone will make a digital amp that can switch between Dirac, Anthem, Room Perfect, etc. like Dolby or DTS processing in a HT receiver. It would be nice to pick which one you like best. I'm very happy with Room Perfect, but the audiophile in me wonders if the others offer different flavors of DSP goodness. :)
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For a swarm, I'd recommend starting with a sub in each front corner, the 3rd sub placed along a side wall and the 4th sub placed along the rear wall.
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nickd, you already have servo subs built into your main speakers. You can just add a pair to the back of the room and you're done.
And did you ever get those speakers built out and playing yet?
I have a gut feeling that those will be very good.
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I have 2 more 12" sealed boxes left over from an older Super V project. I will build out the other 2 subs in the next month and start working on a true "Servo Swarm". :thumb:
Nick -- We'd love to read about your experience with building a servo swarm!
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Here's a shot of my third sub. It's next door neighbor is my HT sub. Love the finish on that thing. Amp box install and wiring clean up will probably be the first audio project for the new year.
BTW -- room is 13x20x8.
(https://www.audiocircle.com/image.php?id=201936)
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Yeah, if someone has a youtube video link or simple instructions for the non-tech savvy on how to integrate multiple subs, please provide it here. I don't know where to start, so I'm relying solely on my ears.
One of my recommendations to Danny was to do a Tuesday Tech Talk where he actually goes into someone's home and shows us how to conduct measurements, recommends treatment options, makes speaker placement suggestions, and sets up the open baffle subs properly.
I wrote this years ago:
https://www.audiocircle.com/index.php?topic=155030.msg1659006#msg1659006
Recently I helped a colleague who had a pair of GR Research NX Otica’s with Triple 12 inch OB/Rythmik’s as all of you know. Bass was good but not perfect. He added 2 more sealed subs and now it is golden. Did everything with REW and a MiniDSP to integrate the sealed subs. Done.
Pretty much everything we/he did is in that thread I linked above which has several systematic requirements and articles to read (which give you detailed instructions!). It’s a learning curve but very do able. Each person’s room and situation is different so the 1st thing that must happen before you integrate the subs is you must become an expert at measuring your room/speaker system. REW is popular and free and constantly upgraded. There are entire forums dedicated to it so I would definitely work at it. Hate to say it and as I learned years ago, you have to shovel some poop to reach nirvana with bass! A rite of passage so to speak! On my last effort I integrated 4 subs over a weekend. Once upon a time it took me an entire month to do.
Best,
Anand.
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I wrote this years ago:
https://www.audiocircle.com/index.php?topic=155030.msg1659006#msg1659006
This is awesome. It should be a sticky somewhere.
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Early B,
Thanks for the complement, but honestly on this forum there is very little if any interest in achieving bass perfection through REW and measurements. Everybody wants one stop shopping and the easy way out!
I'll leave you guys with this:
LF response, 50 dB vertical range, 5 dB vertical scaling, no smoothing:
(https://i.imgur.com/DypMTon.png)
LF response, 70 dB vertical range, 10 dB vertical scaling, no smoothing:
(https://i.imgur.com/gwQ0kxx.png)
LF response, 50 dB vertical range, 5 dB vertical scaling, 1/12th octave smoothing:
(https://i.imgur.com/k33maXi.png)
LF response, 70 dB vertical range, 10 dB vertical scaling, 1/12th octave smoothing:
(https://i.imgur.com/8XrI7Ka.png)
LF response, 70 dB vertical range, 10 dB vertical scaling, 1/12th octave smoothing, with Target Curve overlay:
(https://i.imgur.com/ZQ08ai6.png)
LF response, 50 dB vertical range, 5 dB vertical scaling, psychoacoustic smoothing:
(https://i.imgur.com/pv0iyWA.png)
That is what you get with didactic measurements and (4) asymmetrically distributed subs. Took me 3 days, 6 hours each day. The ramp up in the bass from 150Hz to 20Hz was on purpose, subjectively sounds a little more dynamic on the lowest octaves. The dip around 50Hz is a ceiling mode which is audibly harmless as you can tell in the 1/12th octave smoothed measurements and is also a very small range of the bass spectrum. The area close to 200Hz is the Schroeder frequency transition. Room dimensions are 16 feet wide, 10 feet tall, and 26 feet deep. The only area of boost EQ that I have is around 15-30Hz. There is no EQ from 30Hz up through 300Hz. Just overlapping of subs, xo points, xo slopes, gain, and phase. No delay used at all. Subjectively, it's hard to tell you what it sounds like, it has to be experienced. On my next post, I'll show the waterfalls (CSD) in the under 300Hz range if there is any interest.
If you guys have questions, please ask.
Best,
Anand.
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I wrote this years ago:
Each person’s room and situation is different so the 1st thing that must happen before you integrate the subs is you must become an expert at measuring your room/speaker system. REW is popular and free and constantly upgraded.
A quick google search reviels that to become and expert 10000 hours is required. Some quick math on my phone... 416 days 24 hours a day. UGH!. When I attempted this it was a struggle. Sure i didn't try for 4 years at 8 hours a day but i put in a good effort. I bought all the stuff. Physical hook up of the wires, learning new software. posting, resizing, asking questions... days and days turned into weeks. And I still wasn't even close to anything. It really sucked the fun out of it for me. AND the sweeping sound drove me crazy after 10,000 times.
I spend a lot of time on the Klipsch forum and those guys will tell you that unless you have a active crossover you will never achieve the right measurments. Not just the bass but to time delay the upper end... its really over whelming.
Most of the time my system sounds lovely....until i open up the computer and start reading forums. :duh:
NO one has been as hepful as you @Anand when dealing with this. I'm still grateful. Thanks!
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guf,
I was at Burning Amp just recently, I should have visited you! My parents live in San Jose.
Yes, of course I have a Behringer DCX or you can use a Minidsp or equivalent for the subs. I do not use any active crossover on the mains however, only for the subs. It takes time, but one of my colleagues who has GR Research NX Otica with a pair of Triple 12 OB Rythmik subs along with (2) other sealed 15 inch subs achieved excellent results as well and he was pretty much an REW noob. He is retired, so he had some extra time. I did help him through Facetime, and we are now close colleagues. The time and learning curve is the reason why Duke LeJeune's SWARM setup for most fellas is a bargain! He'll do it for you.
Thanks for the compliments.
Best,
Anand.
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nickd, you already have servo subs built into your main speakers. You can just add a pair to the back of the room and you're done.
And did you ever get those speakers built out and playing yet?
I have a gut feeling that those will be very good.
Danny,
Q4 for my company is crazy. Haven’t had time to finish them. Will likely build the extra 3 subs at the same time after December.
Borrowed some speakers with powered subs to get me through the holidays so although I’m anxious to hear the Hot rodded Elipticor III’s, I have to wait a bit.
(https://www.audiocircle.com/image.php?id=202021)
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Nick,
Cool speakers.
Here are the waterfalls, and low frequency spectrograms. They both tell the same thing. Bass basically decays quickly and cleanly, with little to no ringing whatsoever, except below 35Hz in my case (where you want some ringing for HT effects!). Midbass etc...is clean.
(https://i.imgur.com/o0ii5C3.png)
(https://i.imgur.com/GtghkNy.png)
Best,
Anand.
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Early B,
Thanks for the complement, but honestly on this forum there is very little if any interest in achieving bass perfection through REW and measurements. Everybody wants one stop shopping and the easy way out!
Yeah, you're right. We're audiophiles, not sound engineers. Learning to take measurements at the level you're talking about seems exhausting and antithetical to the goal which is to sit back and enjoy the music.
Besides, most of us don't control our audio space -- we share it with wives, kids, friends, etc. So whenever someone, for example, tells me to get some room treatment, I just shake my head. I think the best approach and question for most of us is -- "Based on my situation (budget, room size, WAF, time, etc.), how can I achieve the best possible sound?"
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Yeah, you're right. We're audiophiles, not sound engineers. Learning to take measurements at the level you're talking about seems exhausting and antithetical to the goal which is to sit back and enjoy the music.
Besides, most of us don't control our audio space -- we share it with wives, kids, friends, etc. So whenever someone, for example, tells me to get some room treatment, I just shake my head. I think the best approach and question for most of us is -- "Based on my situation (budget, room size, WAF, time, etc.), how can I achieve the best possible sound?"
Fair enough. First and foremost I am not a sound engineer and my job is far away from anything to do with audio engineering or acoustics. What I did discover years ago, was that achieving good bass (i.e. the frequencies above 10Hz and below 300Hz) has more to do with measurements and acoustics than it does about setting things with the human ear. The ear is useful with the end result (as a final judge or arbiter if you will) but it has an inability of taking you to the end result in an expeditious manner (i.e. you can spend years/decades). Measurement software like REW in particular is now free or inexpensive and very powerful. It is also constantly upgraded which is a boon. A dedicated room isn't required but a yearn to improve one's 2 channel experience is (and honestly your room might be dedicated 'enough' given that you are able to fit 3 subs). That is the only thing that drove me. Of course I was initially driven after having experienced the end result in another audiophile's home (an audition always helps!). I used and still use the measurements as a tool towards an end goal. And to be honest, there are entire forums dedicated to helping audiophiles achieve this end goal, it's just not that popular here. I can only encourage you to make those measurements and post them on AV Nirvana where the designer of REW participates. You don't have to use REW though as there may be other measurement softwares that are easier to learn or use. I am not aware of them, nor did I explore them as I found REW rather easy to use.
Achieving an improved bass response only helped me enjoy my music more. Soundstaging blossomed, midbass detail was greatly enhanced, and midrange/treble detail was far more apparent as I was not concentrating on bass issues in the room. Dynamics were unshackled. Bass ceased to be an impasse to the music being expressed. It literally was a night and day difference.
Perhaps the method in which I did it was somehow overzealous to you (and to others) and an antithesis to being or becoming an 'audiophile.' Yes, during the time that I spent measuring I wasn't listening to or enjoying music. But I was learning. And that is powerful.
Best,
Anand.
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Fair enough. First and foremost I am not a sound engineer and my job is far away from anything to do with audio engineering or acoustics. What I did discover years ago, was that achieving good bass (i.e. the frequencies above 10Hz and below 300Hz) has more to do with measurements and acoustics than it does about setting things with the human ear. The ear is useful with the end result (as a final judge or arbiter if you will) but it has an inability of taking you to the end result in an expeditious manner (i.e. you can spend years/decades). Measurement software like REW in particular is now free or inexpensive and very powerful. It is also constantly upgraded which is a boon. A dedicated room isn't required but a yearn to improve one's 2 channel experience is (and honestly your room might be dedicated 'enough' given that you are able to fit 3 subs). That is the only thing that drove me. Of course I was initially driven after having experienced the end result in another audiophile's home (an audition always helps!). I used and still use the measurements as a tool towards an end goal. And to be honest, there are entire forums dedicated to helping audiophiles achieve this end goal, it's just not that popular here. I can only encourage you to make those measurements and post them on AV Nirvana where the designer of REW participates. You don't have to use REW though as there may be other measurement softwares that are easier to learn or use. I am not aware of them, nor did I explore them as I found REW rather easy to use.
Achieving an improved bass response only helped me enjoy my music more. Soundstaging blossomed, midbass detail was greatly enhanced and midrange/treble detail was far more apparent as I was not concentrating on bass issues in the room. Dynamics were unshackled. Bass ceased to be an impasse to the music being expressed. It literally was a night and day difference.
Perhaps the method in which I did it was somehow overzealous to you (and to others) and an antithesis to being or becoming an 'audiophile.' Yes, the time that I spent measuring, I wasn't listening to or enjoying music. But I was learning.
I admire your fortitude and don't doubt that what you did significantly improved the sound of your system from the top down. At the very least, I should try and figure out how to set the PEQ on my A370 amps. The Rythmik website ain't much help. I've always kept the PEQ in the "off" position. Today, I turned them on, set everything at 12 o'clock, popped in some Stanley Clarke, and could already see the benefit of tinkering with the PEQ if I knew what I was doing. I won't make any promises, but I'll look deeper into how to measure my room and go from there.
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Yippee! The acoustic gods are smiling :P
Sometimes I feel that fellas give up because of “analysis paralysis.” I hear it all the time on phone calls with audiophile colleagues.
Best,
Anand.
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I'm with Anand here. REW has been a big help in getting my subs dialed in. Both with using the PEQ to bring down humps and with Phase to get the subs properly aligned with the mains. REW shows me where the problems are and gives me feedback on exactly what a change I made did. It lets me see how a change compares with what I had before the change and lets me write notes about a change. This way I can keep track of what I'm doing. Once I've dialed everything in individually with REW, I sit back and listen. If something sounds off, I may tweak the physical position. Once I no longer hear what was off I recheck REW. Sometimes when I move something the phase will be off again so I readjust then listen again. Once I'm satisfied with what I'm seeing on the graphs and with what I'm hearing I'm done. For one listening position, this takes me about 4 hours, but I haven't added a rear sub to the mix yet. Once I have time, I'll incorporate the HT sub in the back of the room for music also.
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The concept behind swarm is to limit bass production to the subs alone, big full range floor standing speakers need not apply as they act as subs in the very wrong room locations if set up away from walls for the best imaging performance. (Side by side subs just double the in-room bass peaks/dips.) Am a believer in room first, swarm second, treatment third, and room correction software last. Sorry if that's not what you want to accept, knowing that achieving a better room shape/size can be terribly inconvenient. Again, I'd apply REW/Dirac last as it only applies to a narrow listening area and so provides an artificial versus a physical/natural solution. This follows Earl Geddes' teachings. We all know of audiofools who way over spent on gear for the given space.
Keep in mind with all this that it's all about the room shape/size 'fighting' against the physics of bass sound wave sizes and how those waves function in a residentially sized room which can easily cause 10 - 20 dB peaks/dips. A tiny room is bound to be near cubic - a horrible sounding space. A long skinny room is bound to sound like a tunnel. A large but low room sounds claustrophobic. The ear adapts quickly leading to sonic confusion but ideally the room shape should follow something like the Fibonacci ratios (3:5:8:13:21) to minimize induced peaks/dips, refer to Toole's "Sound Reproduction".
The swarm concept is to even out the in-room bass peaks and dips by spreading out the 3 or 4 bass sources (ideally in a staggered manner). Again refer to "Sound Reproduction". I have my subs in a Fibonacci ratio of spacings from the corners. The experts suggest locating one sub off the floor and trying one sub out of phase.
Room treatment is another whole can of worms but know that the size of the sound waves (10-50ft) precludes the use of diffusion. So absorption is the only alternative and most materials are poor absorbers of bass frequencies. Owens Corning 703 fiberglass is the best material, that's why I have ten 2ft x 4ft GIK 244 panels in my room.
I know you younger computer oriented guys want a software solution, but in most cases DSP is a bandaid when the patient needs surgery. DSP should considered as the icing on the cake and only applied last. If you're saddled with a crummy room, can't install subs, and can't add treatments suggest using headphones.
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JLM,
While the thread is about the benefits (and set up) of additional subs, DSP is more available now than ever. I lived without it for 35+ years with many tube and SS systems. Horns, OB, Line Source, monitors, floor standing etc. Some from the worlds best designers.
My room is 14’ 6” w X 23’ d X 9’h. Some room treatments and a pop out to get the gear out of the room. I have a 18” custom transmission line sub built in to the pop out because it is huge and would not fit in room.
After investing in quality DSP based room correction, I could never go back. I’m sure I would have kept my LS9’s if I would have known how much difference room correction can make.
My rig offers a “bypass” mode that brings you back to reality. With the last 10 pair of Loudspeakers in my room priced from $300. monitors to $30,000. Reference grade towers, the improvement is always surprising.
While I agree with you that DSP might not be my first advice “go to” for improvement, good room correction software in a quality processor is game changing.
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FOLLOW-UP...
I looked into learning how to conduct my own measurements, downloaded REW, watched a few youtube videos, visited some forums, etc., and quickly realized once again -- hell, no! Too much time and energy is required for me to learn it.
Instead, I invited a technically-astute, audiophile friend over my house to measure my low end room response using REW. Actually, it measured quite well, with the exception of a minor bump at 35Hz. We made a couple of attempts to remove the bump, but eventually, I was happy to leave the settings as is.
I finally sat down with a extended listening session last night and really like what the third sub is contributing. At times, it's subtle, but during bass heavy passages, it thumps hard! Love it. The vast majority of music I listen to is jazz vocals, so bass isn't a prominent feature of this genre until an upright bass is played or the drummer jams out. It's during these moments when the third sub provides a 3rd dimension to the bass, almost like an echo. It's akin to the difference between a drummer in a small jazz club vs. a lively concert hall. Hard to describe, but natural sounding nonetheless.
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Good discussion fellas. I'm working through a lot of the same issues.
My main rig is in my living room, so, lots of compromises as a result.
I have two IB infloor subs (2-15" in ea) located right in front of my speakers. I am contemplating two more behind the listening position. Although I have both crawl space above and below the room, there are limitations as to where I can put them due to duct work etc..
I will be using a Berhinger 2496 to do the xover and some processing. Still working on the high pass as I want to keep upper bandwidth (between 80 and 100Hz and up) analogue and pure as possible. I have Dalquist DQ-LP1 that needs recapped (know anyone?) and will give this a try.
Anyone have success with a Passive Line Level XO? That may be the way to go as well.
(https://www.audiocircle.com/image.php?id=202531)
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Have heard an attic installed I.B. sub, crossed over very low (40 Hz as I recall), wasn't impressed. But the theory is good. Why do are you thinking of adding more I.B. subs? Have you measured bass peaks/dips? Again, best to stagger bass sources around the room to avoid peaks/dips, otherwise you could just add to the problems. How acoustically inert is the "infinite" space on the back side of the woofer (a big issue with I.B. just like any bass source)?
Also had a Behringer 2496 (a DEQ2496). Hideously difficult to learn (thanks YouTube), but effective if your particular unit is reliable (a known issue). Bought a modded version to use as a DAC and DEQ later on. If it works why look for another solution? Tried an "indirect" solutions (one device to measure, another to make adjustments) that left me wondering just how accurate the whole approach was. And had a DSPeaker Anti-Mode 2.0 Dual Core that measured/adjusted <250 Hz (the correct bass cutoff frequency IMO). But its display was too tiny to be useful.
Now have Dirac Live (<500 Hz) built into my NAD M10 but with my 3 subs is still confusing. Depending on the music, get the best sound with sans Dirac/subs, subs sans Dirac, or with both in play. This is an 8ft x 13ft x 21ft room, mid-field listening, ten GIK 244 panels, and three tall randomly filled bookcases on side walls.
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"Have heard an attic installed I.B. sub, crossed over very low (40 Hz as I recall), wasn't impressed."
Mine needs some integration work but from what I'm hearing at this point, they have tremendous potential. Very efficient and very low distortion. With just a moderate amp, they have gobs of headroom.
"Why do are you thinking of adding more I.B. subs?"
To implement a swarm and/or "out of phase" strategy. Why IB instead of conventional? because of room and ease of build with of crawl space above and below the room. I suppose I could use "in room" subs but would need to hide them in a "behind the couch" scheme or a coffee table/sub build. Both much more difficult, more expensive and less efficient than IB.
Have you measured bass peaks/dips?
Yes… kind of. I have a microphone but REW has been extremely challenging for me. I have a bit more work to do before I dive in and try to make some decent measurements. But from what I’ve done so far, I have huge dips at 220 Hz and 50 hz… from what I understand that’s typical for untreated domestic rooms. There is also a hump at 100Hz. The rest of the response looks good.
best to stagger bass sources around the room to avoid peaks/dips, otherwise you could just add to the problems.
That’s the plan with the “back” subs. In either an out of phase strategy or a swarm strategy. The front subs wont be moving.
How acoustically inert is the "infinite" space on the back side of the woofer (a big issue with I.B. just like any bass source)?
The sub floor is dirt and the ceiling is roof rafters. Both have more than sufficient cubic feet to adequately support IB.
Also had a Behringer 2496 (a DEQ2496). Hideously difficult to learn (thanks YouTube), but effective if your particular unit is reliable (a known issue). Bought a modded version to use as a DAC and DEQ later on. If it works why look for another solution?
Yes. Learning curve was steep, but I got it working OK. Had to work through a problem getting it a strong enough signal. I don’t want to use the Berhinger as a high pass xover. Will need something else for that.
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I use a Xilica xp 3060 for my subs and super mini base. It’s a dsp active crossover 24/96 40 point floating processors phase peq multiple crossover settings adjustable every 1hz. I got to it used for 600$ but new they were around 1500$. Everyone on the Klipsch forum loves for horns cause there opamps are pretty quite and there xlr in out with super low output impeadance. I also have a Marchand xm46 passive line level crossover that uses caps inductors and resistors. You can buy different modules for your crossovers or you can use there online calculator and do it your self. I really like my Xilica and along with room eq wizard it’s super easy to setup subs.