Thats exactly the current plan unless there is something wrong with it. I'm building 7 line arrays. Yes I know its overkill for one room but I wanted to standardise on a design and make all channels the same. Current thought is that they will be ported to around 80hz. Should be okay according to some people that have used these drivers. But while 80HZ might be okay for the surround channels they seem a bit weak for front speakers. The issue I'm struggling with is the following.
In a good HT setup wouldn't you want the front speakers to be capable to play lower then 80hz and then the LFE handles only the very low end?
Sources will be plugged into a normal receiver and the pre-amp output for each channel will be plugged into the mini-dsp to handle the crossover and eq.
So I will be dependent on the receiver to handle the main bass management. If all speakers are set as small, I assume the receiver will redirect all low frequency to the LFE. If this will work perfectly then this will be my preferred setup.
It sounds like there are many possible setups.
1. All front speakers as small speakers, plus IB LFE (2 towers) to handle all content below 80hz.
2. Front 2 speakers large, done as 2 way plus IB bass towers as the 3way on two channels, center as small and no LFE.
3. Front 3 speakers large plus IB LFE.
Will these options be same sound if receivers bass management does its job?
Option 1 is what I prepared the IB holes for. With option 2 I could still use these holes as a way to make the 3 way towers smaller. But I only have 2 holes in my floor. Option 3 I would add woofers to the front channels and make them 3 ways but only if it will be a much better option.
Whats your opinion on the optimal setup?
I'm getting ready to order the active setup and amplifier part so I would need to finalize my design.
Any help is appreciated.
Cheers.
The best setups are true full range 20-20kHz bi or tri amped speakers on each channel plus several LFE subs, which mirrors what is installed in very high end theaters (IMAX)
You don't have that, so the next best is to set everything to small and let all the bass go to the LFE channel. That will keep low frequency signal from muddying up your mains and will increase intelligibility all around.
I wouldn't tune the mains to the Fxo. If you have to use bass reflex for the tops, tune much lower than your expected crossover point or it will be very difficult to align the two systems.
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Hi,
Personally I don't like line arrays, and I don't think anyone should build
7 of them blind without having experienced them in 2 channel mode.
FWIW I have a pair of speakers with 2ft ribbon mid/tweeters, which
circumvents most line array issues and and I still don't like them much.
No way would I build all seven channels the same, that's expensively pointless.
What I'd suggest to go with the 2 massive but fairly cheap bass modules is taking you pick from :
Zaph|Audio - ZA5 Speaker Designs with ZA14W08 woofer and Vifa DQ25SC16-04 tweeter
Ideally what you want is an AV amplifier than lets you vary the c/o
to each speaker, the lowest to the left and right, higher for the
centre and higher still for the other channels.
It makes sense to me to have the "ZA5.5tt - MMTMM 2.5-way vertical array"
+ bass modules for 2 channel music duties and add the lesser rest for AV.
Not sure you'd actually need 12 x 15's to go with the above, but if you want
7 identical speakers that do go loud above 80Hz you could do a lot worse
than the "ZA5.5tt - MMTMM 2.5-way vertical array".
rgds, sreten.
Personally I don't like line arrays, and I don't think anyone should build
7 of them blind without having experienced them in 2 channel mode.
FWIW I have a pair of speakers with 2ft ribbon mid/tweeters, which
circumvents most line array issues and and I still don't like them much.
No way would I build all seven channels the same, that's expensively pointless.
What I'd suggest to go with the 2 massive but fairly cheap bass modules is taking you pick from :
Zaph|Audio - ZA5 Speaker Designs with ZA14W08 woofer and Vifa DQ25SC16-04 tweeter
Ideally what you want is an AV amplifier than lets you vary the c/o
to each speaker, the lowest to the left and right, higher for the
centre and higher still for the other channels.
It makes sense to me to have the "ZA5.5tt - MMTMM 2.5-way vertical array"
+ bass modules for 2 channel music duties and add the lesser rest for AV.
Not sure you'd actually need 12 x 15's to go with the above, but if you want
7 identical speakers that do go loud above 80Hz you could do a lot worse
than the "ZA5.5tt - MMTMM 2.5-way vertical array".
rgds, sreten.
The issue is that I have all the drivers since 5 years at home! (except the 15" woofers)/ Thus for me to change and go for another design, I need to spend funds for new drivers and then suddenly I will find a wife that will be very upset that I previously spent all that money getting massive amount of drivers delivered from the US.....
Just this week I built a very simple test line array of 16 4" drivers that I currently run open baffle and full range. I actually don't hate it but it sure does not have any bass. This will tell you that I am not a very experienced audio connoisseur.
Okay I don't think its feasible to dream about a more capable system. I think I should just settle for my option 1 and figure out the best/cheapest 15" woofer. MCM is currently the one but they still have not responded to my mail.
I have a mail out to STX as well. They have another 15" driver that have 16mm excursion (p.p). SW.STX.15.3.800.8.F.S.MC - Kino domowe, g?o?niki, kolumny - STX polski producent
Hi,
The latest driver you posted Qts is far too low for IB.
Good luck with the mains, they are far more important.
rgds, sreten.
Have you considered this driver? Dayton IB385-8 15" Infinite Baffle Subwoofer 295-455
shipping 2 drivers vs 12... enough said.
Two of them wired in parallel, one in each IB tower next to your mains would do fine. Also power both of them with one SPA500 or similar amp. Dayton Audio SPA500 500W Subwoofer Plate Amplifier 300-807
shipping 2 drivers vs 12... enough said.
Two of them wired in parallel, one in each IB tower next to your mains would do fine. Also power both of them with one SPA500 or similar amp. Dayton Audio SPA500 500W Subwoofer Plate Amplifier 300-807
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Some of the best theaters have common characteristics:
identical arrays for LRC and surround which ensures continuity of timbre during pans.
80Hz crossover to LFE to prevent lfe localization.
solid room build to prevent localization of resonances and allow deep bass propagation, stabalize standing waves and control reflection without smothering reverb and ambience retrieval.
a good place to look might be the THX site for room design hints.
also remember that the best theater is the one you forget your in.
A poorly designed theater will even make you dislike a movie, ive experienced it.
I hope you can post some pics of the build, im stoked to see this monster theater!
identical arrays for LRC and surround which ensures continuity of timbre during pans.
80Hz crossover to LFE to prevent lfe localization.
solid room build to prevent localization of resonances and allow deep bass propagation, stabalize standing waves and control reflection without smothering reverb and ambience retrieval.
a good place to look might be the THX site for room design hints.
also remember that the best theater is the one you forget your in.
A poorly designed theater will even make you dislike a movie, ive experienced it.
I hope you can post some pics of the build, im stoked to see this monster theater!
Room shell is now almost done. Its room within a room and it has some extensive sound insulation done. Sand filled stage, riser platform and sofits are now done. I'm now going to finalize some electrical and ventilation and then I will be ready for acoustic treatments and finishings.
Thus I'm now needing to get cracking on the speaker side.
I have looked at the dayton IB driver, its very well priced for a very capable IB subwoofer but I feel 2 will be to few for a proper IB. I also really like the idea of many drivers sharing the load...impressive at least.
I have pretty much decided that I will go with identical 2 ways across all 7 channels. I have also decided that I will pair them with 2 bass towers which will contain many 15" woofers.
Any other suggestions regarding cheaper woofers that can be sourced here in Europe?
Merry Christmas!
Which software are you using to model the above drivers? Anything free? I'm on a Mac which makes it difficult but I hope to install parallels desktop which will enable me to work with windows soft.
I have pretty much forgotten about the MC electronics drivers. I called and was told they cant send them in international package due to the magnets. I also have forgotten about the STX drivers since they don't seem powerful enough with low xmax.
I'm now leaning towards car subwoofer drivers from Germany. I found the following drivers that are interesting.
the ASX15 at http://www.audiodesign.de/downloads/tsp/Hifonics.pdf
The xmax figures are for back and forth travel but still one way will be 35mm. I assume 4 of these at around 200E each will be a good IB choice at 22L of displacement. They have received some good reviews in German sites (google translation is good
http://www.audiodesign.de/downloads/testberichte2011/ASX15.pdf
But I wonder if they will model good enough to work all the way to where my 2 way front speakers will give up around 80-100hz. Will they also require mega big power to work well? I will have class D modules of 250W so I could dedicate one module of 250W for each subwoofer for a total of 1000W for the full IB solution.
Will this be a better solution then two bigger towers with more drivers of less capable 12" woofers? Say I used 12 of the BX12 in the above list the expenditure will be similar but will it be a better or worse solution?
Thanks...
Which software are you using to model the above drivers? Anything free? I'm on a Mac which makes it difficult but I hope to install parallels desktop which will enable me to work with windows soft.
I have pretty much forgotten about the MC electronics drivers. I called and was told they cant send them in international package due to the magnets. I also have forgotten about the STX drivers since they don't seem powerful enough with low xmax.
I'm now leaning towards car subwoofer drivers from Germany. I found the following drivers that are interesting.
the ASX15 at http://www.audiodesign.de/downloads/tsp/Hifonics.pdf
The xmax figures are for back and forth travel but still one way will be 35mm. I assume 4 of these at around 200E each will be a good IB choice at 22L of displacement. They have received some good reviews in German sites (google translation is good
http://www.audiodesign.de/downloads/testberichte2011/ASX15.pdf
But I wonder if they will model good enough to work all the way to where my 2 way front speakers will give up around 80-100hz. Will they also require mega big power to work well? I will have class D modules of 250W so I could dedicate one module of 250W for each subwoofer for a total of 1000W for the full IB solution.
Will this be a better solution then two bigger towers with more drivers of less capable 12" woofers? Say I used 12 of the BX12 in the above list the expenditure will be similar but will it be a better or worse solution?
Thanks...
Am I doing it right?
Okay did some modeling using bassbox. Not sure if I am doing it right though.
Following graphs are for 4 of the Hifonics ASX 15" subwoofers in an IB (20m3 box). First scenario is with 1200W power (one amp board of 300W for each woofer) and second one with 3400W power.
First scenario give me 116db at 20hz and 108db at 10hz with a cone excursion of 20mm at 10hz. Second scenario give me 120db at 20hz and 112db at 10hz with a cone excursion of 33.6mm at 10hz.
Does this look good? What does these figures really mean though. To little, enough, or to much? The extra amp power will cost a bit so is the difference of 4db going to be noticeable?
Okay did some modeling using bassbox. Not sure if I am doing it right though.
Following graphs are for 4 of the Hifonics ASX 15" subwoofers in an IB (20m3 box). First scenario is with 1200W power (one amp board of 300W for each woofer) and second one with 3400W power.
First scenario give me 116db at 20hz and 108db at 10hz with a cone excursion of 20mm at 10hz. Second scenario give me 120db at 20hz and 112db at 10hz with a cone excursion of 33.6mm at 10hz.
Does this look good? What does these figures really mean though. To little, enough, or to much? The extra amp power will cost a bit so is the difference of 4db going to be noticeable?
Attachments
Notice 4db, no. At 116db at 20Hz what you will notice is all the things in the room that are not glued down.
For thx spec you only need 112db at 35Hz and 105db at 20Hz. Are you planning to use the minidsp to eq these flat / cut the upper frequencies?Yes I have one channel on the mini DSP for the subwoofer and I will splitt it into two boxes. I will do the eq and filtering there.
Do the woofers look good? One thing I'm worried about is that people usually say IB woofers should not have to low Cts. These have 0.39 Cts.
D in mm 387
Xmax mm 70 (two way travel)
SD qcm 804
Mms g 223
Re Ohm 4
Fs (Hz) 27
Qms 4,5
Qes 0,42
Qts 0,39
VAS (L) 139
SPL (dB) 90
Le mH 1,5
VC mm 76
RMS (W) 850
Depth (mm) 189
Opening(mm) 352
Do the woofers look good? One thing I'm worried about is that people usually say IB woofers should not have to low Cts. These have 0.39 Cts.
D in mm 387
Xmax mm 70 (two way travel)
SD qcm 804
Mms g 223
Re Ohm 4
Fs (Hz) 27
Qms 4,5
Qes 0,42
Qts 0,39
VAS (L) 139
SPL (dB) 90
Le mH 1,5
VC mm 76
RMS (W) 850
Depth (mm) 189
Opening(mm) 352
Have not fully figured it out yet. But I have the drivers since 5 years back. They are the old Partsexpress buyout NSB 4". And ApexJr tweeters.
The miniDSP boards are on route and hopefully will arrive beginning of January. Same with the amplifiers. Right now I have one crude line array connected with only 16 of the drivers running full range and open baffle.
I'll need them to play well down to 80hz at least and thus are considering ported. I will probably have each set of 4 drivers ported. I will also try a line array version that has two woofer lines of 16 drivers and see if that helps.
I went ahead and ordered the subwoofers in the end. 4 of the 15" Hifonics Atlas. Have always been interested in trying the IB but will be open for other designs as well.
The miniDSP boards are on route and hopefully will arrive beginning of January. Same with the amplifiers. Right now I have one crude line array connected with only 16 of the drivers running full range and open baffle.
I'll need them to play well down to 80hz at least and thus are considering ported. I will probably have each set of 4 drivers ported. I will also try a line array version that has two woofer lines of 16 drivers and see if that helps.
I went ahead and ordered the subwoofers in the end. 4 of the 15" Hifonics Atlas. Have always been interested in trying the IB but will be open for other designs as well.
I received the drivers. Very heavy and quality it seems. There was a separate sheet with the thiele/small parameters and an xmax linear that was different to the published specs. They have "only" 16.4mm xmax linear and 35mm is the Xmech.
Well I'm obvious disapointed but most probably will try to do something with them anyway or loose close to 200E in shipping costs.
So IB maybe out but what else could I do? Shall I do 4 small small boxes with one driver each? 2 boxes with 2 drivers each? Shall I have 2 boxes in the front and 2 in the back?
Cheers,
Kosta
What are the new TS specs? Personally for my home theater room I have two subs directly under the projection screen which has the mains (R/C/L) behind it. The subs are aligned with the L and R mains. Basically it's set up just like i'd set up a premiere in a real movie house, just smaller.
Hi,
They are the same as above but the xmax instead of 35mm is 16,4mm linear in one direction.
Behind the screen next to the mains sounds like a good way since I rather have them out of view. Should I make one box for each woofer or combine 2 woofers in one box?
Hi there,
Two Dual opposed subs would be nice, four separate sealed boxes spread around the room would give a flatter response.
5 cubic feet gives a Qtc of .673 (two drivers) which would be good for HT.
Personally I would go with two boxes (two drivers each), 9 cubic feet tuned to 26Hz, using a 8" port would be fine, you would need a HPF at around 20Hz.
The ported box will do around 120db @ 30Hz, and 111db @ 20Hz.
The dual opposed will do around 113 @ 30Hz, and 107db @ 20Hz, 102db @ 15Hz
Both designs can handle 1Kw, the ported design gives you twice the output of the sealed at the expensive of taking up more room.
John.
Two Dual opposed subs would be nice, four separate sealed boxes spread around the room would give a flatter response.
5 cubic feet gives a Qtc of .673 (two drivers) which would be good for HT.
Personally I would go with two boxes (two drivers each), 9 cubic feet tuned to 26Hz, using a 8" port would be fine, you would need a HPF at around 20Hz.
The ported box will do around 120db @ 30Hz, and 111db @ 20Hz.
The dual opposed will do around 113 @ 30Hz, and 107db @ 20Hz, 102db @ 15Hz
Both designs can handle 1Kw, the ported design gives you twice the output of the sealed at the expensive of taking up more room.
John.
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