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BOSSOBASS Raptor system 3


Madaeel

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My "opinion" is that you should take a minute to check the content of the soundtracks that we rate in the content forum, so that you may re-familiarize yourself with the bandwidth of the content in those soundtracks.

 

Hopefully, that should cement your understanding of the bandwidth of the content we have to deal with in order to accurately reproduce that content.

 

BTW, with all due respect, the data you'll find there is not my opinion. ;) I keep to the facts in this debate. I don't care what is palatable, but there should be no denying what is vital to achieve accurate playback... not "parlor tricks", whatever in the hell that's supposed to mean. You say that my stating the facts of the matter is really only stating my opinion on the matter then you talk about joining some imaginary list of people who prefer losing 2 octaves of playback because, in your opinion, it's all you need. Cool... got it.

 

What I have found is that same frequency response and same levels, two different rooms will NOT reproduce that content in the same way as has been discussed above. So if a tree falls in the woods and nobody around, does it make a sound? Of course it does, but who cares? So those sitting on concrete and sitting on a nice suspended floor with everything else the same will have a very different opinion on same content.

 

The other thing that has been discussed before is that some are better at recognizing the content no doubt. When we were comparing caps and sealed (needed more displacement for that room) in Archaea's space. They could hardly pic out the low note in Bass I Love You. I said I could and closed my eyes and pointed out every time said content was reproduced. Extremely subtle, but I still want it there.

 

I get it, you take a hard lined stance because somebody needs to. The more noise we make about this, the better chance we have of the actually influencing the guys that have the choice in if this content should be included in the soundtracks instead or a couple more dB at 30 Hz. We all know there are plenty of hard line "can't hear nothin belough 20 Hz blah blah blah" out there. Some of the teams and or directors influencing these soundtracks being released should be embarrassed at the clipped compressed garbage with a few octaves lopped off they are putting out. At the same time educating others on this important topic of extension and headroom utilization is paramount in getting this message across. If you get to defensive or in your face about it, I am afraid that turns a lot off and they go build another resonant system to have a Marty party and talk up how BA the last Transformers movie was.

 

I used to get worked up about those running 15, 20, 25 dB hot. Now I say who cares, have a good ole time, but I don't care too much of what they think of a soundtrack when running the bass that much over reference. A recording of my grandma farting would be pretty intense at those levels. At the end of the day it comes down to having fun and enjoying how we decide to reproduce said content. If somebody chooses to chop of an octave or two of said content, knowing what they are missing out on, good for them. They still are reproducing more than the commercial arena. Heck I have seen more than one instance of someone with gobs of output to single digits, with a 40" monitor, 6 1/2" drivers in mains, and zero room treatments. IMO they would have been better off allocating some of that somewhere else. Heck I explained all of this to a relative of mine on concrete and he is doing two 11 cu. ft. low tuned subs with the UM 18's that will be hidden behind false wall. After he has finished up the rest of the theater and made all other purchases, big deal we order more drivers, amps, wood, and have a nice fire with beers next winter with the old enclosures.

 

I don't post much anywhere anymore as I am just having fun and tired of the Audio VIdeo Shill site. With the knowledge on this site, I don't have much to add and can't as eloquently say it as the next guy to post. Your subs and Adam's room and setup are both a knock out of the park. I guess I can still pat people on the back though. :)  I have nothing but the utmost respect for you and all you have done on the low frequency front. You have brought the importance of <20 Hz to the table and keep the discussion going. I enjoy reading all you have to say, but I don't see the need to waist time (like you commented about a couple pages back) telling this group of guys. Probably 90% are running sealed setups and love them, including myself.

 

I wouldn't be surprised if I alter or completely rebuild my riser on concrete multiple times over the coming years to see changes in presentation. I will try out multiple TT's to see what they are all about along the way as well. I don't disagree with anything Scott said about my current iteration, but f it, I am having fun.  :o The crowson's have a 30 day return, try them out before knocking them. I think they are great.

 

Dildo's? Nut massagers? Whatever are you on about, old man? :P

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Well said, Luke. It's all about having fun and enjoying YOUR own system.

 

 

Btw, Jon and I really enjoyed your system and your TT install. I was just comparing it to the Crowson's in that previous post.

 

I know Scott and we even discussed price of admission and how I ended up where I am at. A different riser, possibly with a couple Crowsons under might be something I explore down the road. Not going to get too far without constructive criticism and I welcome it. I come from a car audio background, so enjoy feeling the bass more than most others I assume. I am not one promoting a limited bandwidth system and "filling in" with a TT. I do think they and or nearfield have merit in complimenting a broadband system wanting a little more without distorting the presentation with huge house curves or sub level.

 

It was a real treat to have you over and pick your brain a bit. If you ever make it this way again, you are more than welcome to stay or stop by whenever. Looking back I wish I would have turned the TT on and off and played with levels. I just played it the way I enjoy it, so YMMV. Next time. B)

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So I finally got around to watching X:DOFP and Interstellar. Talk about violent! That was my favorite Xmen movie so far and 2nd in bass with First Class still being king. Interstellar though was the first movie I didn't run hot. That was one loud movie. Scared the crap outta me a couple times. Loved the movie and the AV. Yah it clipped in a couple places that I noticed but I thought the bass was well executed, dug deep, and loud. Actually that was the first movie I ran below reference. ;)

 

What's up with all the sealed vs ported debate?? Sealed is the HNIC. :lol:

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Hey you have mentioned something about single frequency sine waves or even sweeps being irrelevant to actual playback a few times. :D I was siding with you on that one and responding to the post about 105dB at 5Hz which I read as being all that was required for most users. You've said many times the wide band complex content is what counts for movie playback. In most cases a sealed system with 105dB of headroom at 5Hz will have similar headroom up till the 15-20Hz range in room. If the system is intended to be flat down to the sub 10Hz zone it is going to take way more than 105dB of headroom at REF playback levels for something like WOTW, Hulk, or HTTYD . Depending on listening habits, the room, etc, of course.

 

Hope that made sense. In a rush...

 

It makes sense. I just want to be crystal clear on the 126dB thing in that there are no soundtracks with a requirement for that playback level at the single frequency of 5 Hz. If so, it would be impossible to play back.

 

The peak hold graphs show what's required at 5 Hz, which is -15dBFS on every 5 star movie. If you reckon that FS = 121dB (those 5 star movies you mention are all 5.1 soundtracks), that means 106dB at 5 Hz, but roll off and room gain mate nicely with 105dB as a nice round number.

 

For the guys who love it loud (really, I could not care less who prefers what, just stating the facts here), <15 Hz becomes a much higher mountain to climb:

 

b1657691ecd1fc6ea3dbaaa993c434a2.png

 

Pushing it +15dB hot or more makes 15 Hz doable but below that impossible, regardless of the number of drivers. Commercial subs will compress accordingly and DIY will clip accordingly because they're unanimously under powered.

 

Keeping the drivers at Xmax makes reference level easily doable, with headroom.

 

What I'm saying is that almost every poster who claims flat-to-5 Hz by posting a non-calibrated Omnimic FR showing 90dB at 5 Hz with sine wave input CANNOT play WOTW at +15dB hot and retain the 5 Hz content. So, commenting on that performance has little to do with actual reference playback at 5 Hz.

 

Currently, Adam's roll off allows for +15dB operation because, IMO, his room is so well built and transmission loss is a big factor as well. Even so, as he may flatten his signal chain roll off in the future, he will be less able to run those 5 star movies at +15dB hot without exceeding the capability of his system.

 

The bottom line is that people who equate running the subs at +15dB hot or more with having fun prefer resonant alignments because they have no other choice. Even Pop's system with 32 x 18" drivers only added +6dB to his 16 x 18" system. Running a system that hot is about fun and not about accuracy, so lopping off a couple octaves is imperative.

 

Not only do I not object to that sort of sport audio, I included 9 native curves to allow the system to accommodate that pursuit. One just has to know the mechanics of the task and not forget to ENGAGE.

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So I finally got around to watching X:DOFP and Interstellar. Talk about violent! That was my favorite Xmen movie so far and 2nd in bass with First Class still being king. Interstellar though was the first movie I didn't run hot. That was one loud movie. Scared the crap outta me a couple times. Loved the movie and the AV. Yah it clipped in a couple places that I noticed but I thought the bass was well executed, dug deep, and loud. Actually that was the first movie I ran below reference. ;)

 

What's up with all the sealed vs ported debate?? Sealed is the HNIC. :lol:

 

Awesome. Glad you finally got to check those out. Both good films, but Interstellar is a unique experience, IMO. When they travel into the black hole, not only is the low end amped but the front L&R high end is as well. Takes a pretty good system to handle all of that and the sound assaults the listener like no other soundtrack I remember.

 

Also glad to hear you went flat. I honestly think that acclimating to a flat presentation gives a higher ability to evaluate a good mix and a greater appreciation of the system when bumping for fun. IOW, you can tell when the mix sux and when the subs are hot because you're brain is educated to a balanced system. Just my opinion, as I made the effort from the beginning to keep things flat and venture out from there. I tested every sub I built at reference level. It's a great standard for testing system capability and for listening.

 

What's HNIC?

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In my best Aretha Franklin from The Blues Brothers voice:

 

DON'T YOU  BLASPHEME IN HERE!

 

JSS

:lol: :lol: Man I was dyin after reading this! I actually would like to hear you say that haha.

 

In my defense it was 2am and Jazzy was sleeping. I couldn't believe how hot that was recorded. I had it at -10 from reference with the subs 5db hot and almost every scene sounded like it was at ref. That's DTS for you. I realized for most tracks the DTS soundtrack is much hotter than DD. I know they run the surrounds hotter but it seems like every channel is at least 5db hotter than the DD counterpart.

 

Awesome. Glad you finally got to check those out. Both good films, but Interstellar is a unique experience, IMO. When they travel into the black hole, not only is the low end amped but the front L&R high end is as well. Takes a pretty good system to handle all of that and the sound assaults the listener like no other soundtrack I remember.

 

Also glad to hear you went flat. I honestly think that acclimating to a flat presentation gives a higher ability to evaluate a good mix and a greater appreciation of the system when bumping for fun. IOW, you can tell when the mix sux and when the subs are hot because you're brain is educated to a balanced system. Just my opinion, as I made the effort from the beginnng to keep things flat and venture out from there. I tested every sub I built at reference level. It's a great standard for testing system capability and for listening.

 

What's HNIC?

Agreed. I loved Interstellar and bought it because you and a couple other guys' comments. When I got to the black hole scene I had it at -15 from ref and it STIll sounded amazing! I knew that was digging deep. Wish I had my Speclab up and running for that one. I'm gonna watch the movie again a little louder next time.

 

I have been running the subs around 5-10db hot lately and usually it's just 5. I have been thinking about what you said about replacing the concrete with a suspended floor around the seating area. I'm not gonna do the work so the idea doesn't bother me. ;)

 

HNIC=Head n**** in charge. It's from an older movie with Morgan Freeman. Prolly would be funny if anyone knew what the hell I was talking about haha.

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The peak hold graphs show what's required at 5 Hz, which is -15dBFS on every 5 star movie. If you reckon that FS = 121dB (those 5 star movies you mention are all 5.1 soundtracks), that means 106dB at 5 Hz, but roll off and room gain mate nicely with 105dB as a nice round number.

 

FWIW, digital 5.1 FS = 123 dB.  That means -15 dB actually requires 108 dB, in case anyone's counting.  Of course, it's always possible something will come around (such as the space shuttle recording I posted) that demands more than that at reference.

 

Edit: I checked out a few PvAs of heavy hitters, and it looks like5 Hz content above 105 dB is not unheard of.  Many films have content at or exceeding 115 dB (e.g. HTTYD) at frequencies somewhat above or below 5 Hz.  I don't think aiming for 115 dB output at 5 Hz is unreasonable for reference level playback.

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Thanks to Paul and Adam's referral I have spec lab up and running. The only problem is that my UMIK sucks below 10hz so it shows I have rolloff which I don't. I would love to see my true results with Bosso's measuring gear! When I get back in town I will throw some spec labs up, where should I post them?

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FWIW, digital 5.1 FS = 123 dB.  That means -15 dB actually requires 108 dB, in case anyone's counting.  Of course, it's always possible something will come around (such as the space shuttle recording I posted) that demands more than that at reference.

 

Edit: I checked out a few PvAs of heavy hitters, and it looks like5 Hz content above 105 dB is not unheard of.  Many films have content at or exceeding 115 dB (e.g. HTTYD) at frequencies somewhat above or below 5 Hz.  I don't think aiming for 115 dB output at 5 Hz is unreasonable for reference level playback.

 

So, you 'checked out a few' and concluded that 'many' have higher levels at 5 Hz? I assure you, it's not many.

 

115dB is not entirely unreasonable, unless you believe there will be zero room gain at 5 Hz, then it's unreasonable. In my experience, 105dB at 5 Hz is the requirement. If there's a system that capable of 115dB @ 5 Hz before room gain, please post a link to the data.

 

That would be around 35 LMS-Ultra 18" with 100,000 watts and zero signal chain roll off. :)

 

The BHT-15 gives around 73dB @ 5 Hz @ 2M. Raptor System 3 gives around 91dB @ 5 Hz. I have 22dB of room gain at 5 Hz, total = 113dB @ 5 Hz. I have measured every soundtrack available showing clean reference reproduction at 5 Hz at the seats (4M). Since I know my system is not capable of 115dB at 4M @ 5 Hz cleanly, I must conclude that a requirement of 115dB @ 5 Hz is an incorrect calculation.

 

Here's the in-room compression sweeps graph posted 4 years ago when first tests of the Raptor began:

 

274b2dec64b05f4c2af98ee65f608200.png

 

HTTYD's toughest scene shows accurate repro to 4 Hz at the seats with zero 2HD, 3HD, 4HD, etc.:

 

8e08652b6a3eec5369351661ab2b8161.jpg

 

The evidence I've gathered is pretty compelling. That's not to say that I think there will never be a soundtrack that demands more, but that's another discussion altogether.

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123.2 is the sum of ((5*105) + 115) when the signals are coherent (e.g. as per http://www.sengpielaudio.com/calculator-coherentsources.htm)

That link appears to be bad.  In any case, start from the definition of SPL:

 

SPL = 20*log10(P/P_ref)

 

Derive an expressions for P of each type of source and the sum of all sources:

 

P = 10^(SPL/20)*P_ref

P_LFE = 10^(115/20)*P_ref

P_MAIN = 10^(105/20)*P_ref

P_5.1_TOTAL = (10^(115/20) + 5*10^(105/20))*P_ref

P_7.1_TOTAL = (10^(115/20) + 7*10^(105/20))*P_ref

 

Evaluate the total SPL (the P_ref value cancels):

 

SPL_5.1_TOTAL = 20*log10(10^(115/20) + 5*10^(105/20)) = 123.24

SPL_7.1_TOTAL = 20*log10(10^(115/20) + 5*10^(105/20)) = 125.14

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One more thing.  My recent reading suggests that the 85 dBC calibration standard should really be treated as "85 dB (nominal)".  Apparently, using the Dolby pink noise signal and measurement equipment with the standard calibration procedure leads to a system that produces closer to 83 dB per channel when using C-weighted -20 dBFS RMS pink noise.  So actually, the 121 dB figure for 5.1 (and 123 dB for 7.1) may be closer to reality for a system calibrated to "85 dB (nominal)" using the standard Dolby tools.

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Bosso,

 

I've gone from a very capable ported sub setup with my two JTR captivators to a very capable sealed system with eight 18" Ultimax 18 drivers.

 

Your strong opinion that sealed is the only palatable answer and frequency responses below 15hz is vital, is simply that --- your opinion.  I personally add my name to the list of those that disagree here.

A sub that reaches to 15hz is all I need, and having owned both capable sealed and capable ported systems -  I can say I would be perfectly pleased with ported subs tuned to 15hz, in anything other than a room with a suspended wooden floor.   On a suspended wooden floor - sealed do come into their own and manifest some fun parlor tricks.

 

My frequency response is now flat to below 10hz, and nearly 7Hz on a basement slab in my big room.  See FR capture here taken by DesertDome at the recent KC crawl this last weekend.  This is a no smoothing capture with his omnimic.v2.  It was taken from the MLP.

http://www.avsforum.com/forum/15-general-home-theater-media-game-rooms/1525397-archaea-s-multi-purpose-home-theater-room-28.html#post33827977

qqbd41.jpg

 

Besides my use of the nearfield sealed I don't get any perceived value out of the sealed subs below 15hz when they are placed at the front of the room.  I do think the sealed nearfield are worthwhile (so much so that I'd probably take one sealed nearfield 18" over the other seven subs loaded at the front of the room) - but quite honestly the two captivators were 95% of the performance of these eight sealed, and they were tuned to 20hz natively.  Considering I paid nearly double the money in total for these eight sealed (amps, boxes, wiring, drivers) over the two ported captivators -- I wouldn't be disappointed to go back to a pair of caps or equivalent tuned to 15hz, and put nearly $3k back in my pocket.  Real world performance was only a hair different in my experience.  If I went to different subs up front I'd probably want to keep the sealed nearfield --- I've grown quite fond of them in that position.

 

I guess I'm just pointing out that you seem to maintain that anyone who disagrees sealed is the only game in town hasn't experienced otherwise - and that's just not accurate.  I now own one of the more capable sealed systems, and I'm certainly still excited by a pair (or more) of high capability ported subwoofers, or horn subwoofers.  (Orbit Shifters, Gjallarhorns, etc)

 

I have tried three different amps on my Captivator Pro pair.  The EP4000, the Inuke DSP 3000, and the Crown XLS-5000.  The Crown is the only one of the three that can pretty much be counted on to drive the JTR Caps for what their worth.  I use a single amp in all cases and my subs are wired for 2ohm.

 

Arch,

 

I've had a few minutes since last week to look at this post and I'm wondering if you can provide some details?

 

Do you have a FR of the near field sub? I mean no harm here but a 1x18 near field besting 7x18 far field? Honestly? I'd like to compare the FR you posted to the near field response, per previous discussions here on the subject. It's useful info.

 

Beyond that...

 

How on earth is the Dayton system $3k more than a pair of passive Caps + XLS-5K? Maybe I'm missing something, but weren't the Caps $2k each plus the Crown amp?

 

 

Eight of these Ultimax 18" subs (2K), and two iNuke DSP 6000 amps ($800) makes a world beater setup on a comparatively cheap budget.

 

IOW, I have to say that I think you're laying some silly putty here with the cost vs performance claims (1x18 near field bests 7x18" far field, dual ported Caps + Crown XLS-5K = 95% of 8 UM 18s + dual iNuke 6Ks, 6th order roll off at 20 Hz = flat to <7 Hz and putting $3K back in your pocket, etc). You seem to have been saying the exact opposite in posts elsewhere. Nevertheless, actual data says you're exaggerating the ported rig's abilities, at a minimum.

 

An honest comment posted here is appreciated, but your post seems a bit tainted by Cap worship and/or a seriously entrenched position from previous debates on the subject with others. In any case, filling in the blanks would be appreciated, if you see this post and have the data. :)

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Random post to back up Dave's comment on very low frequency gain. My data for my current room shows a gain of roughly 5dB at 16Hz, 14dB or so at 10Hz and a massive 28dB at 7Hz. My data for frequencies lower than that is somewhat suspect due to equipment roll off and bad SNR in the outdoor results. 30dB at 5Hz would seem to be about right at least in my room. This is all comparing to 2m ground plane/ 1m anechoic. YMMV

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