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Waterboy77,


You'll not have to worry about how close the Mackie C200 are to the AT screen You can have them right up against it and you won't get any movement. The ports are plenty big on the Mackie C200 and I've never seen them move my screen even though they are right up against the AT fabric. Also you'll likely cross them over at 80hz or there abouts - and you'll probably never see the 10" driver move much at all - even at reference levels.


You will want to toe the Mackie C200 in. I personally like them aimed at the center seat position.


I'm still happy with these Mackie C200 --- with Audyssey mutiXT32 engaged and for the price I don't know how you could really beat them - even with DIY. Street price is $170 shipped at nearly any bigbox movie store with the recurring 15% off coupons that are generally available on any given holiday.


I got compliments on them from some of the KC home theater crawl folk. They far outperform their pricepoint, and excel for a very inexpensive cinema speaker. I've been around the block on the home theater electronics circuit and found I think a practical and reasonably inexpensive setup like the Mackie C200 really delivers to levels, and beyond, that general enthusiasts seek. Yes there are better speakers, and some might want or need more --- assuming the requirements of above reference listening -- that's fun for a quick demo --- but really I'm never going to listen to a full movie that loud. (at least I don't think so) :) If money was no object, then something like JTR would be my absolute go to (something like @dlbeck's theater with all JTR speakers is nothing short of phenomenal)---- but if funds aren't unlimited, I'm satisfied with where I landed on the price to performance scale.


When @Scott Simonian visited from CA for the recent KC Home Theater tour, he and @Luke Kamp, and I , and a friend of Luke's watched Gravity at -3dB from Reference and that's the loudest I've actually ever watched a full length movie in my theater. I thought the sound was great and didn't notice a single weakness from the speakers the entire movie. The center channel voices sounded crystal clear - no small boxy sound that typically spews from inexpensive or overdriven speakers. I have no reason to listen to a movie louder than that. In fact, though it was fun and sounded great, I typically wouldn't even listen that loud -- preferring more like -12dB as my typical go to volume --- of course with the subwoofers running 6-15dB hot - depending on the movie. When a scene that is really cool arrives, sometimes I'll rewind and pump the volume -- but for the full - movie -- I don't need it at reference levels.
 

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I think professional design services yield benefit.
So do capable speakers, and all the more for capable subwoofers.

However, I think that with just some homework and reading on the forums (something you seem willing to do) you can derive a enjoyable experience without the expense of professional services. (not that professional services don't have their place)

We recently hosted a KC home theater crawl with five different hosts in greatly differing rooms and with greatly differing costs of equipment/room. Two were professionally designed and setup, three were not - I enjoyed each and every room on the crawl.


Craig John implemented a dead front, live back room design, and it remains, perhaps, my favorite room treatment for sound of those I've visited.

As for drop ceiling. Look long and hard at Certainteed Theater Black F tiles. They work EXCELLENTLY, 3% light reflectivity, and .75 NRC. Put R30 pink fluffy above them in the floor joists and you'll have a much higher NRC. They don't rattle either like typical white drop ceiling tiles. My original white ceiling tiles rattled like mad everytime the bass hit. My certainteed tiles are silent. No changes to the grid. If I had to describe them, they are basically OC703 tiles with a light absorbing black material on one side.

https://www.certainteed.com/products/ceilings/by-brand/performa/314184
http://www.certainteed.com/resources/CTC_Performa_Theatre_Black_f.pdf
 

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Thanks for the feedback. I am certainly willing to and already have done lots of homework and reading. Just need to make better notes :eek:
Do the five hosts have build threads I can go through?
What did Craig John do for treatments?
Do you know what their factors where for using and not using professional services?
Here is the KC HT crawl thread. You can read through the thread to see people's impressions of the rooms and pictures of the rooms. I took some video from each I need to upload. I'll work on that tonight.
http://www.avsforum.com/forum/61-area-home-theater-meets/1898233-kc-crazy-2015-theater-crawl.html

Craig John's Room Thread
http://www.avsforum.com/forum/29-what-s-your-system-configuration/1349395-craig-john-s-theater.html
 

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Are you looking for cimema theater volumes for show off sessions?

If so, four sealed 10"s won't do it.
(And even if they make it to reference volumes it'll probably be 35hz and up ---not flat frequency respnse reproduction all the way down to 20hz which is kind of the minimal ideal starting point imo)

Four 12s would be better, but probably won't get you to reference.

Four 15s would probably get you flat 20hz-120hz cinema reference volumes if you seats are close to them.

If you like to run your bass hot and want to play at reference volumes you are probably looking at four 18" sealed subs.

Don't expect any of these systems to pressurize your space with 6800 cubic feet.

General guidelines...
 

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12 Gauge Copper wire should be fine for 18" subs. Monoprice is pretty much as good as any for price. Don't buy CCA. (copper coated aluminum)
http://www.roger-russell.com/wire/wire.htm#wiretable

You want to rival a movie theater, you'll need four 15"s or 18"s -------- or more.

I can confidently say my bass with eight sealed 18" subwoofers is far superior to any movie theater I've visited, including the local (AMC headquartered in KC) flagship AMC Primes, and Dolby Cinema Primes of which there are only a handful of these premier theaters in the entire nation. (
 

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omnimic just works.


REW has hassles.

I've used both, I've seen both used multiple times.


You can pull the omnimic from my cold dead fingers. I'll give you REW for the price I paid for it.


I don't want to be fiddling around with setup endlessly, and try to iron out weird random problems all the time. I want to pull my mic out, take measurement, and move on. The real-time measement with omnimic is invaluable. I can go to any room with any Windows PC, and take an accurate SPL calibrated measurement in less than a minute. If they have the capability to play a CD or a mp3/wav file (what home theater doesn't?) - that's all I need.


Home Theater Shack reached out to me at one point through PM and asked if I'd consider becoming an official subwoofer reviewer there, but they had a couple conditions - neither of which I was comfortable with. One was to drop Omnimic and start using REW, because REW is promoted there. I'm glad they make a great tool, and it's free, but like I said, I've played with both, and I'm going to pull out the easier to use, hassle free tool every time.


Dessertdome used to be a big proponent of REW, he relatively recently bought an omnimic, and conceded that for ease of use and immediate startup time the omnimic has his vote, and it's what he uses most of the time now, even though he still knows the ins and outs of REW. I know there are guys that love their REW. I'm happy for them, and I'm happy there is a free software option and I truly applaud the design team and ongoing improvement efforts and the fact Home Theater Shack keeps it free. I just like omnimic better for my casual use. The all in one package, with realtime sweeps so you can see exactly on the graph what that 2% angle to-in or physical replacement of the speaker 2" to the left does to the frequency response at the MLP. It's truly so easy a cave man could do it.


As to optimizing your room to the nth degree with treatments, frankly I'm just not that into that. I've been in many rooms at many avsforum home theaters, and room optimization/speaker optimazation is easy to do in a major way without all that expense that makes it a tad bit better. Use the REW or Omnimic tool to optimize initial physical placements - let your AVR's auto EQ take over from there. I had a super live room in my last theater room and I loved it. I have a more dead room now, and I love it. I don't get too uptight about the details. I'd be happy in either type of room again -- and I had lots of compliments about both rooms. Just optimize the subwoofer placement to start with as flat of an EQ as possible in the MLP, and likewise optimize the speaker physical placement and toe them in to your preference and K. I. S. S.
Use some common principles that seem to work well. Deaden the front wall, use carpet where you can, if you have a drop ceiling install sound aborbing panels an pink fluffy above them, if not install a couple absorption panels like @carp did. Play with absorption panels on the side wall if you like, or buy speakers that have more limited dispersion horizontally (constant directivity type for instance) and toe the L and R in a bit. Don't automatically assume absorbion panels at the first reflection point is the right thing to do because some people say it is. Maybe contra-lateral panels are what you need? Maybe like me you'll find you don't even need panels at first or contra-lateral positions and you're happy with the sound as is. I ended up hanging some 3" studio foam in kind of a strange, unexpected place on the wall behind my computer monitor because I was hearing a bit of a slap echo originating strongly from there. It wasn't really a measured thing. It was an audible fix.


Sure, my room could probably be a bit more optimized with a proper acoustic engineer at the helm - but IMO, I'm pretty happy with the results as is - in just playing around with stuff and using these basic principles. My room, IMO, easily bests any commercial cinema I've ever visited except the newest AMC Prime (premiere flagship theater), and my bass is better than the prime, so I'm really only giving up a little bit to the main speakers (JBL line arrays) the seats, (electric recliners - super comfy) and laser projectors (which are phenomenal). All of which if purchased and installed would probably 10x + over increase the cost I've spent on my room - for no where near that level of appreciation over what I have.

If you want a recommendation on a good professional acoustic design person - dlbeck used Niles from Acoustic Fontier, and his theater is the best I've ever visited --- so I'd start there. dlbeck has very solid recommendations for Niles. Niles planned absorption, diffraction, and reflection treatments down to 1/4" IIRC in dlbecks room. And obviously it worked... I'm just not at that level, not really sure I need to be at that level for my personal financial and interest level.
 

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There is a school of thought that I mostly agree with, that you should rotate the speakers to the lesser degree angle in a theater where you have that ability - ESPECIALLY, perhaps exlusively? in a home theater with multiple rows.

IIRC, some well experienced people like @beastaudio, and @dlbeck, and @Scott Simonian, @desertdome, etc have even recommended putting your side surrounds slightly before the front row, and putting the rear surrounds on the back of the side wall, (more in a typical surround speaker position) - because our ears can hear the differences in the surround field better that way.

I've not played with that myself, but having sat in a few home theaters where that concept was employeed it does seem to work generally pretty well IMO. It's at least worth consideration. I know I mounted my rear surround closer to the dolby spec placement (using the maximums because of room constraints --- used about 110* for sides, and about 150* for rears) and even though I have two speakers back there, I'd never know if it was the left rear playing or the right rear speaker playing because my ears can't easily identify the diffference unless only one speaker is playing a test tone at at time. In actual content - to my ears - it's all just rear fill the way it is with the Dolby spec - so I might as well have just used a single speaker back there --- this is to my ears anyway. Putting the rear surrounds on my side walls would potentially have given me more of an ability to discern from which side the rear surround speaker is playing.
 

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I've got a shorty rack so I can't comment - all of it is below my waist - but ideally you'd put your hottest things towards the top so as your heat rises it doesn't saturate everything to the same temp as your hottest item if it sits on the bottom. Hottest thing may be your AVR... Especially if it's a higher class flagship unit or an Onkyo. :) (can't only say Onkyo because my X4520 and now X7200wa Denon also run hot --- but why the heck is the prepro Onkyo 5508 so hot -- it doesn't even have internal amps????? Onkyo just runs hot for the fun of it apparently. My fomer Onkyo 1007 would almost burn your hand after a movie, and there was nothing on top of - it was sitting on top of the rack in free air.


At any rate - you don't want that kind of heat soaking up through your gear if you can avoid it.
 

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yeah 12 gauge should shore up any concerns for most distances --- but a 75 foot run is pretty darn long --- what impedance is your subwoofer setup going to be using?


This should put your mind at ease somewhat. The Crown XLS-5000 is noted to be a beast of an amp and actually put forth a great deal more power than forum favorites like the Behringer EP4000. Even the Crown manual says you should be fine with 16 gauge wire up to 25foot. For 75' it should be 10 gauge minimum according to Crown.
http://www.avsforum.com/forum/155-d...-speaker-wire-should-used-3.html#post21595273


2.5 Choose Output Wire and Connectors
Crown recommends using pre-built or professionally
wired, high-quality, two-conductor, heavy gauge
speaker wire and connectors. You may use 2-pole or 4-
pole Speakon® connectors (Figure 2.5 ), banana plugs,
or bare wire for your output connectors (Figure 2.6). To
prevent the possibility of short-circuits, wrap or otherwise
insulate exposed loudspeaker cable connectors.

Using the guidelines below, select the appropriate size
of wire based on the distance from amplifier to speaker.
CAUTION: Never use shielded cable for output
wiring.
Distance Wire Size
up to 25 ft. 16 AWG
25-40 ft. 14 AWG
41-60 ft. 12 AWG
61-100 ft. 10 AWG
101-150 ft. 8 AWG
151-250 ft. 6 AWG



-------------------------


There is more knowledge in that thread than I can impart.
FWIW - I actually used 12 gauge for my subwoofer runs just to be safe but none of my runs are over about 25 foot.
14 gauge is fine (read overkill) for your 8 ohm mains


Also ------ don't forget you can double up your speaker wire and it effectively is the same as 3 gauges larger. So doubling up two strands of 14 gauge speaker wire becomes 11 gauge - if that's a cheaper route for you. (four runs of 14gauge wire would be the equivalent of 8 gauge).
Man, 75 foot is a LONG distance, You should consider running your subs at 8ohm instead of 4ohm or 2ohm if you have the ability to ease the cable concern.
 

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pros and cons to 8 ohm vs 4 ohm vs 2 ohm?

Virtually nothing in home theater application use in relation to sound quality.
It's more practical than that --- higher ohm load is easier on the amp, but requires more powerful amp to get the same power output levels, and allows for thinner cables without introducing audible distortion (at a given length). By contrast, a lower ohm load is more strain on the amp, but produces more output, and requires thicker copper cables. :) (super generic explanation)

More details:


2 ohm stereo is the same as 4 ohm bridged in regards to the amp's load.
4 ohm stereo is the same power output as 8 ohm bridged.


Generally this is the way amp power scaling works......

So e.g. - the Cerwin Vega CV-5000 puts out
2500 watts x 2 channels at 2ohm stereo (and 5,000 watts at 4 ohm bridged)
or 1800watt x 2 channels at 4 ohm stereo (and 3,600 watts at 8 ohm bridged)
or 1,100 watts x 2 channels at 8 ohm stereo (and likely (but unadvertised) 2,400 watts at 16 ohm bridged)
etc etc etc....


The CV-5000 is capable of running less than 2 ohm stereo, but it is limited by the power supply from producing much more than what it is rated for a 2 ohm stereo. That's typical of some of the nicer amps (speakerpower, etc) - they can run lower impedance than rated for - but they can't really produce any more power because the power supply is already 'mostly' maxed out at their 2 ohm rating. For instance. I run my CV-5000 at ~ 3ohm bridged right now on three nearfield UM18-22 subs wired to 1 ohm each. (they have dual 2ohm voice coils)



The historical guidance is running at 2ohm stereo is harder on the amplifier and is to be avoided in pro applications (that old adage is generally only applicable for pro audio DJ use where you are running an amp at max tilt for entire evenings --- some DJ professionals would tell you the only reason you should ever run an amp at two ohms is because one of your 4 or 8 ohm loaded amplifiers died and you are doubling down speakers at the lower impedance on the surviving amplifier to get you through the show at the same volume.) Running an amp at 2 ohm stereo creates more heat, and can stress the power supply more heavily. That said, LOT and LOTS of us AV enthusiasts run 2 ohm stereo in our home theater environments without any issue. Myself included when I had the 2ohm Captivators. I ran those successfully on a EP4000, an iNuke DSP 3000, and a Crown XLS-5000 at 2 ohm without issue. (well I did blow up a EP4000 - but that was fan modded and run for all she was worth at 2 ohm until she let out the magic smoke shortly after maxing her out. I think if I hadn't fan modded that unit it'd still be fine, cause my next new EP4000 never had any problems at 2ohm :) )

There is some dampening factors to contend with based on ohm load and cable distances but some people who understand much more about audio than me say dampening is pretty much completely negligible to our human ears in any given home theater setup - even if it can be measured with scientific tools. So you can probably pretty safely disregard anything related to dampening factor. The concern is pushed more heavily in audiophile circles.


You have a couple options. You can place your amps close to your subwoofers, and run a long XLR cable to provide signal - but that might introduce hum/noise into the signal line which is then amplified and annoying. Otherwise at those distances you probably ought to shoot for a 4 ohm load or 8 ohm load with the subs, run a long speaker wire, and just plan on buying more powerful amplifiers to account for your 4 or 8 ohm subs. It really isn't that big of a difference when you boil it all out.


Remember that a doubling of power is effectively only 3dB louder. So if you gave a sub 1,000 watts vs. 2,000 watts - the sub will only be 3dB louder with the extra power. That's basically three ticks on your AVR volume dial ---- say -13 to -10 main volume. Not that big of a deal at the end of the day. Quadrouple the power gets you ~six dB.




This might be time for another call so I can explain all the details out more easily. You still have my number?


No matter what your ohm rating on your subwoofer driver you can effectively reach many other common ohm configurations by using multiples of that driver. See some of these calcs to learn how that works...
http://www.the12volt.com/caraudio/woofer_configurations.asp
http://www.rockfordfosgate.com/rftech/woofer_wizard_form.asp
http://www.crutchfield.com/S-jdjsah9pOJ2/learn/learningcenter/car/subwoofers_wiring.html
http://www.bcae1.com/spkrmlti.htm
 

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So how many watts does an "average" guys subs need? I say average because I see I lot of over the top base systems in this forum..... ya @Archaea in my little world you are over the top :D

----------


yeah - that question can't really be answered except after you have pickedout your subwoofer driver (also factoring in impedance load), box alignment(ported, sealed, horn?), volume preferences/expectations, and all that thenneeds to be factored into the equation alongside room size and placement(boundary gain) – which is a heavy variable.

Let me give you a clear example. A friend of mine locally @Scrappydue has tocut his bass levels down at 15-20hz via parametric EQ on his four SI 18HT inhis theater room by about 8-10dB and he still has a bit of a house curve.8-10dB is a power factor of more than 4x. By contrast I have to boost my eightUM18-22 subs by that same amount in my room just to get a flat frequencyresponse. So he's cutting by ~8-10dB with half the subs, and I'm boosting by~8-10dB with twice the subs to get to the same basic output levels. I have touse an incredible amount more power and subs to end up at a similar place. He'susing a single iNuke DSP 6000 to power his four subs and he never clips hisamp, rarely uses more than a single light or two of power. I'm using three iNuke amps and a Cerwin VegaCV-5000 amp on my eight sub setup and frankly, probably couldn't get as loud inthe low bass as he can, while easily clipping all four of my amps. A 16-20dB swing is a huge hurdle toovercome. That’s kind of a best andworst scenario though.

This delta measured and verified with two omnimics. His room is a smaller'concrete bunker' type space which is the best scenario for boundary gain, andmine is a larger space and my subs are not loaded against any concrete boundaries.I'm using a baffle wall, and effectively my subs are nearly at a 1/4 or 1/3point depth relative to the actual physical size of the basement's concreteframework. So I get relatively very little boundary gain down low. He's using apittance of the power I am using and getting better results.





As another comparison, @carp has a more powerful bass experience than I canmuster with his 8 SI 18HT and a single CV-5000 amp powering all eight subs. So I have an additional ~15,000 watts ofamplification over carp, and a slightly better driver, and yet his subs can golouder and be observably more tactile (concrete boundaries again, and smaller theater room in his case aswell)



So ---- yeah, it depends.
 

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What the heck happened with my spacing above? :)

I actually don't even know how big my basement is. It's not at all sealed, and it's big, and there are four connected rooms. My house is 3,200 sq feet (not counting basement), and the basement media room is effectively the whole basement, because there are effectively no doors that matter - every room is connected by an open hall at some location. My main space if it was a square is 22 x 28, but there is a baffle wall/storage section that adds another 8' or 10' or so on the 28' depth dimmension and an area the spawns off on the 22' side to probably be 35' still in the same main airspace - and then at least another 20' or 25' beyond that on width dimmension 22' side that is not sealed at all.

I probably just need to measure the outside of the house, and calculate from that for my basement theater space......
 

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I spent a few minutes throwing together a sim in winisdpro. I'm not as familiar with the drivers around here as some of the guys are, but the UM12-22 got some good press on some professional reviews I read, and seems a decent 12" sub for excursion and price. So I started there - there might be better 12" subs for the money. I'm not the guy to ask.

With what you've said about not really needing a ton of bass - a 12" in each column, would be an okay start, but frankly it may leave you wanting. As you'd still be a good 10dB below reference with a couple 12" ported subs. (not counting for distance or boundary gain) A couple 12" in a couple columns would be smoothing bass only IMO. For this sim, You could buy a couple Dayton UM12-22 and port them to 15hz and feed them about 450 watts to them to get a max SPL of about 107 to 108dB SPL at 1 meter. That's in a 6cubic foot cab with 4 ports. You could basically turn your whole column into a subwoofer cab to get the 6 cubic foot of volume pretty easily I think. I suppose you could repeat for all four columns but if they aren't equal distance from the listening position you are going to get into phase misalignments (timing/distance settings) - which is definitely correctable through the iNuke DSP software, but requires measuring equipment like the omnimic or REW and some tinkering time. Depends on if you are up for the task or not?!?!

An Inuke DSP 3000 would do the trick for 2 column subs as far as power and DSP.

The iNuke's do a real good job with voltage limiting (watt limiting basically) You choose the power you want the driver to get, and it soft limits the driver. It won't make any bad noises when it hits the limits - it'll just not get louder and the clip lights will display. So that 450 watts will keep the cone excursion under control, and they'll do real nice until about -10dB on the AVR.

If you want more volume than that you'll either have to raise the ported tune. (yuck), or get bigger drivers. a 12" subwoofer can only do so much. Remember that when you calculate displacement a speaker is a lot more than just a couple inches smaller. Because we are calculating the surface area in total - a larger woofer has much more surface area than a couple inches would lead you to believe. For instance - a friend of mine recently told me his two 5.25" woofers should be about the equivalent of my 10" woofer. I said no. I showed him the math. It's really only the equivalent surface area of about 1/2 my 10" woofer for two 5.25" drivers. Using a simple math calculator for circles which discounts the surround and basket space - a 12" diameter's circle's surface area is about 113", for a 18" diameter's circle the surface area is about 254.5". So two 12" woofers have less surface area than a single 18" woofer - not to mention the larger woofers typically have more xmax (excursion) so that allows them even more displacement, and the surround takes up less space on a single 18" vs. two 12" further favoring the 18"
http://www.calculatorsoup.com/calculators/geometry-plane/circle.php

Truly - bigger is better when it comes to subwoofer displacement.




You could put a couple 18" up front for a bit more SPL. Either ported or sealed. (I like a good strong ported sub up front, but prefer sealed nearfield directly behind my seat when possible) If size wasn't an issue and you only wanted two subs I'd port for 15hz-16hz personally, or get about four 18" sealed instead at minimum. (I thought my two JTR captivators (ported 4000 watt variants) bested 4 sealed Um18-22 and 4 sealed SI 18HT subs. When I did the comparison in two different rooms on two different dates - 6 was about equitable - eight - then the decision went to the eight sealed.

Here is some info on the Dayton Audio UM subs.

18"
http://www.daytonaudio.com/index.ph...2-18-ultimax-dvc-subwoofer-2-ohms-per-co.html
12"
http://www.daytonaudio.com/index.ph...-12-ultimax-dvc-subwoofer-2-ohm-per-coil.html


I've attached the winisdpro sim for you to take a look at.
Download the tool here:
http://www.linearteam.dk/?pageid=winisdpro

Play around with it.

Pay attention to several things
SPL
Cone Excursion
Frequency Response
If you are making a ported box you'll need to look at air velocity too from the ports. You don't want much over low 20's on that number - otherwise the ports will chuff (sound like wind is forcibly being pushed through them)
If I'm forgetting anything I'm sure one of the guys will let me know...
see the attached pictures for some examples...









 

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I wrote up a real long response for the last 30 minutes over my lunch break and it got erased when I pushed something on my keyboard and the browser went back a page unintentionally.


I lack the motivation to write it again.


Suffice to say - with a driver that can handle both ported and sealed --- in correctly appropriated boxes - the driver in the ported will have nearly a 10dB advantage around port tune over the same driver in a sealed box. At the upper bass frequencies the drivers will be pretty much equitable, but that deep bass advantage is significant for ported.


There are a WHOLE lot of caveats here --- that's what I wrote out. But some other time perhaps.
 

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@LTD02

Help! :)

I'm calling on an expert.
I'd be guessing on both questions.

My guesses - I doubt the driver's volume matters enough to really effect the sim terribly on a big ported box.
The port needs to be outside the box or accounted for in the volume calculation - especially with ports that long. (up and down the length of the box one time each x 4 )
 

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why not both?

just cost and effort to results consideration---

We'll probably never see it because of the time/frustration involved in this type of test....but it would be interesting to see an example of the differences between the SPL transmission to the above room with:

  1. No treatment
  2. Roxuol or R30 or something similar
  3. GGDW single layer
  4. GGDWx2
  5. All together

From what I can see - it doesn't appear the second layer of drywall and green glue did much of anything over a single layer in the tests...considering one can see a pretty easy +/- 1dB swing as the testing tolerance to begin with.


For instance - what if DW+GG gives you a 4dB reduction and adding Roxul gives you a new total of 6dB reduction - so total between the two is 6dB reduction, but what if doing Roxul alone gave you a 4.5 dB reduction. Is DW + GG worth the time/cost/effort for this examples 1.5dB of further attentuation? With his DW + GG already up - we won't know what the Roxul would do alone.

Never the less interesting to see some numbers on this for comparison.
 
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