BOSSOBASS Raptor system 3

[dbstedt]

RMS to each driver, average, is 1KW, transient peaks to 1750W.

 

Excellent, thanks Dave!  Just about all the detailed info I could ask for.  I really like the adjustable gain, limiter and bridge LED.

 

I will say that I keep seeing the '7' in that font as a '1'.  Anyways, great work and I hope this amp delivers what we've all been waiting for.  A reliable, efficient and affordable mega-power amp.

 

Cheers!

[maxmercy]

Almost forgot we watched Dredd tonight in 3D......that movie was awesome! I dind't run Speclab though so I could enjoy the movie haha. I DID run it on TIH though at the sonic cannons and when he beats Abomination into the ground. Was ridiculous at 15db hot.

 

Make sure and 'sign' the peitition!

 

https://www.facebook.com/MakeADreddSequel

 

JSS

[Madaeel]

Make sure and 'sign' the peitition!

 

https://www.facebook.com/MakeADreddSequel

 

JSS

WHAAAAAAAAAAAAAA??!

 

That movie was badass. Plus the 3D was pretty good too. I can't believe how great Karl Urban was as Dredd. I of course realized it would be a pretty good action movie but I'm really glad I bought this. I loved it. Definitely signing that. Thx for telling me.

[Madaeel]

Dave sorry for not posting any graphs but 12's have been kicking my ass. Ethan is coming over to watch TF4 tomorrow and I think I'll man up and graph WotW and HTTYD at the MLP.

[Madaeel]

 

 

Here's the scene you were talking about Dave. It felt amazing....even on concrete.

 

I really need a new mic though cuz 125db just ain't enough.

[Madaeel]

 

 

This is one of my favorite scenes ever now. This is the WotW lightning strikes when TC and his daughter run inside the house and he says they never hit twice. Damn this sounded and felt awesome.

 

Forgot to mention this and the ST graph is 15db hot at the MLP with some left in the tank. Sorry Dave but it can handle it.

[Bossobass Dave]

Star Trek warp.jpg

 

Here's the scene you were talking about Dave. It felt amazing....even on concrete.

 

I really need a new mic though cuz 125db just ain't enough.

Hey Adam,

 

Awesome screen caps. Remember to make sure your mouse isn't in the graph when you hit print screen. Just keep it in the left side tool bar and the graph will capture cleanly.

 

First, it's great to hear Jazzy is back home safely. I hope the trip was a good one and I'm sure you're glad to have her back home.

 

I don't think transients have ever gotten the press they deserve. Max and I are fans of playing back transients as accurately as possible. That's why we prefer a track that has higher dynamics and lower levels vs a track with higher levels but compressed transients.

 

You can always adjust the levels at playback to your preference, providing your system has the headroom to allow for it, but you can't restore clipped transients, whether they're clipped via limiters, a compressor or just plain driven above the red line.

 

Transients are extremely difficult to measure accurately because they're, um, transient. Micro-seconds, They also have content to DC, regardless of the fundamental center.

 

That means they're not only difficult to measure, they're difficult to play back.

 

I read an article by Bob Carver in the 80s. Here's a reference to part of the article I found and saved:

 

Once, Bob Carver visited a famous sound researcher who was attempting to recreate the "snip" of an ordinary pair of scissors. He used no less than TWENTY-FOUR 200-watt amplifiers for playback. Yet when viewed on an oscilloscope it was apparent that the top of that instantaneous transition was being distorted. Believe it or not, he needed more power! It was evident that real-world sound occurs very quickly and requires far more power than ANY current amplifier could produce. The M-1.5t is a culmination of Bob's search for enough power, the ultimate amplifier for the reproduction of music today and for years to come. Why such massive amounts of amplifier power? Music is full of surprises such as explosive crescendos, combinant crests of demand created by multiple instrument sounds and the shock levels that some well-recorded instruments can instantly attain. This is what makes music live. These incredibly intense bursts of sound don't necessarily have to be loud. They are too short in duration. But, like the scissor snip, they are intense and demand power. Recorded music sounds dull without these constantly-occurring high instant peaks. If your amplifier cannot provide the instantaneous power to surmount these rigorous musical punches when they are presented at its inputs, it makes a sound of its own devising, literally an electronic gagging we call, clipping. The result is an audible degradation which has pervaded your listening for years.

 

So, the Star Trek warp scenes don't sound as loud as the sine tone chords in the 1st chapter of Edge Of Tomorrow, but they most certainly are at least as loud if measured accurately. And, as the article mentions, compression sounds dull. The main difference between a live event and the playback of the recorded event is existence of the transients. Loudness wars techniques erase transients altogether for the sake of overall loudness. When the transients are preserved in production and the playback is through a system with headroom, the difference is unmistakeable.

 

This is the reason many people will forsake ULF in favor of a large horn, IMO. Back in the Danley DIY thread, there was discussion of why a horn sounds different. There was mention of group delay and other phenomena, but I always felt the logical reason is because the horn is so much more efficient, there is inevitably more amplifier headroom for transients and the subjective comments on the difference between amplifier limited subs and a horn most always harmonize with this.

 

I have made many outrageous statements in the past 12 or so years regarding low end reproduction. One of them was a blanket statement that "all commercial subs are amp-limited". It's extremely risky to design a subwoofer system that has amplifier headroom beyond the capabilities of the driver's mechanical limits, but I believe that anyone who sees the benefits on paper to the point of wanting to purchase a system like the Raptor 3 will likely have the smarts to keep the system operating within safe operating limits. If you require more SPL, get more system.

 

This is also why Josh gets such great results from the raw driver-in-a-box testing. He has plenty of amplifier and knows how to safely use it. For example, the Velo DD-18 is a 1 x 18" sealed sub with a 1250W with rated burst capability to 3000W. Josh tests a 1 x 18" raw driver-in-a-box sealed sub with 6-12dB more amplifier headroom. The results are as predicted.

 

 

I did tests using the "Go after him!" Spock going to warp followed by the Nirada following from Star Trek scene using the same sub with the same calibration only using different amplifiers. One of the tests included a Marathon 5050 (5KW burst rated) vs a Sanway FP 9000, which was in reality a K12000 amp (12KW burst rated). I used my graphics software to overlay the speclab results wherein I could very slowly fade one graph out and in while zoomed in very close so that I could see every pixel in the SL graph. The higher burst capable amp showed better definition which amounted to 2-3dB better rendering of the transient peaks at almost any frequency.

 

Sorry for the long post. I've been meaning to specifically address this subject for a number of years now and the ST scene you posted fits perfectly with the subject. It also fits nicely with what Max & I recently commented on regarding preferring higher dynamics/lower levels vs higher levels/compressed dynamics. It also ties in with my position on under-powered subs with limiters that alter frequency response to make the sub "idiot proof".

[Madaeel]

Thanks Dave. Yah she's glad to be back home. She's not a fan of those plane rides anymore. It's almost 10 hours coming back. I'm happy as hell she's back but working long hours I still barely see her except on the weekends. Oh well at least she's home.

 

I was rushing trying to get a graph up before work and forgot to delete the graph underneath that one. I promised I'd get that to you and was waiting on Verizon to get my internet back up. They should look cleaner from now on except for the mic clipping...

 

That scene in ST sounded awesome. I love the buildup in that scene. I plan on watching that whole movie again.

 

I love that info regarding transients. It reminds me of the conversation we had about a sub that can do this many db at 10hz but when it comes to reproducing a soundtrack like WotW or even the Skadoosh scene it just butchers it. Transients are a little hard to do with 500w when the soundtrack is calling for so much power across the entire subwoofer bandwidth. Speaking of transients here's a graph of the bridge scene in WotW.

 

 

Hmmm. Bob Carver. That explains why he's known for his amps huh. That's just silly that that much power couldn't replicate the snip of the scissors. Great info Dave.

[Madaeel]

Here's the plane crash scene where they're in the basement. Now THIS is one of my favorite scenes. The low's feel amazing in this scene. Plus my mic isn't clipping for once. Pos...

 

 

[Bossobass Dave]

Thanks Dave. Yah she's glad to be back home. She's not a fan of those plane rides anymore. It's almost 10 hours coming back. I'm happy as hell she's back but working long hours I still barely see her except on the weekends. Oh well at least she's home.

 

I was rushing trying to get a graph up before work and forgot to delete the graph underneath that one. I promised I'd get that to you and was waiting on Verizon to get my internet back up. They should look cleaner from now on except for the mic clipping...

 

That scene in ST sounded awesome. I love the buildup in that scene. I plan on watching that whole movie again.

 

I love that info regarding transients. It reminds me of the conversation we had about a sub that can do this many db at 10hz but when it comes to reproducing a soundtrack like WotW or even the Skadoosh scene it just butchers it. Transients are a little hard to do with 500w when the soundtrack is calling for so much power across the entire subwoofer bandwidth. Speaking of transients here's a graph of the bridge scene in WotW.

WotW Bridge demolition.png

 

Hmmm. Bob Carver. That explains why he's known for his amps huh. That's just silly that that much power couldn't replicate the snip of the scissors. Great info Dave.

 

 

Holy shiznit

 

I can't believe you run that scene that hot. I just overlaid my mic'd version of that scene and your cap shows you're freakin' 10dB hotter than I was at the seats. Allowing a dB or 3 for calibration of the mic, etc., that's just insane. Are the drivers still in the enclosures?

 

I NEVER run WOTW hot.

 

Paul said that scene is one of 3 of the top scenes he's measured for maximum voltage to the A14K from the signal chain. I'll bet the max voltage LED on the SEQSS burst into flames... you'd better check it when you get home tonight.

[Madaeel]

Yah I listened 13-15db hot only because at 10db hot the drivers were barely moving and the amp wasn't even close to reaching the VPL. The crazy thing is even at those levels I *still* had headroom. It sounded AMAZING on that scene to say the least. I watched the movie for another 20 minutes afterward and all seemed fine. I'm assuming all is well but I know once I get the Oppo or any pre/pro with less rolloff I can't run that hot. I watch the amp and drivers every time I run a scene for the first time though unless it's a filtered movie.

 

I've been going back and checking graphs for movies I wanna buy and it did crack me up all your graphs are mostly red, and I'm purple, pink, and a little white. So yah I ran WotW hot but in my room at reference and the subs flat the system is coasting. I run everything, except I won't for EoT, 10db hot at -10 from reference to start and go from there. In my room the drivers and amp are barely doing anything at those levels for any movie I've played so far. I still haven't done HTTYD yet but again I know to keep it low to start.

 

Hopefully that makes sense and you don't think I'm just blasting it full tilt to begin with. I'm dumb but not that dumb. Or I tell myself that anyway.

[Bossobass Dave]

BTW, Paul put vids up of the Raptors moving to the EOT and "comin' in hot' scenes on YT.

 

I wanted to mention that Paul is a wicked baddass 6 stringer. He included a 1-1/2 minute riff in there with the excursion vids.

 

He was in a forum somewhere and there was a Stones worshipper arguing with him that Keith Richards was the best guitar player or some such and Paul disagreed. The guy prob said something like "Well, he's definitely better than YOU".

 

So, Paul took a music track of the chords to Sympathy For The Devil and as his response instead of arguing further. Please check it out if you get a minute and a half and, if you do... CRANK!

 

Yeah, I know he's my kid but as a musician everyone who's ever known me knows I don't pull any punches when it comes to commenting on talent. He's just able to play the snot outta a guitar. And, believe me, this vid is just a taste.

 

[BeastAudio]

Ha-ha-ha... Yes, Rowdy Roddy, you nailed it... the Next-Gen it is. It was either that or film my head exploding and put it on YouTube. 

 

Thanks for the kind words and yes, in bridged mode into a nominal 4 ohm load, the amp is all that.

 

I am interested. I mentioned to Paul that you guys outa try and make it up to my g2g this coming Saturday and bring one of those a-14's to play with (and inevitably I will fall in love and buy it), but he said ya'll were a bit busy lately and to look out for the next one perhaps. Love what I am seeing with the systems though, and hopefully we can get up soon! If you guys change your mind @ Saturday, just lemme know man

[Bossobass Dave]

Hey B,

 

Yeah, Paul mentioned the GTG last week and we decided then that we'd just have to wait til the last sec and see if we could shoot up there. I'd love to be there but it really has been a bear of a week for us here.

 

If we do, we'll def bring the necessary hardware to make it a fun time.

 

If we miss it, please come back here and post a thread with pics and vids???

[Bossobass Dave]

My Friday night rant...

 

A friend pinged me with a link to a thread at AVS with the age-old "Ported or Sealed?" question, wherein my name was mentioned.

 

I'm really as burned out on that question as is possible and glad I'm away from AVS for that and similar reasons.

 

Those discussions are always only about peak dBSPL and nothing else.

 

For me, since the very beginning, it has always been about accurate playback of the content on the disc. Nothing more and certainly nothing less. Playback level is achieved by multiples... period. Going from ported to sealed, halve the box, double the drivers and up the power amp from +4 to +6dB. That's the basic rule as I've stated it a go-zillion times over the years.

 

A resonant system offers a peaked response at tune and the price is loss of content + very large enclosure. Why that would still be so apparently hard to grasp in 2014 is beyond me.

 

I use the way I've approached the challenge of reproduction of soundtrack content in my own HT from the beginning as an example. It can also be applied to Adam's HT as well as most every room gain profile I've documented over the years because the room gain profile average is from posted and known response data and is (+/-) 3dB across all of them. Size of room and open or "sealed" room have little to nothing to do with the RG profile curve.

 

When we set up the Raptor System 3 in Adam's room, we ran sweeps to capture the FR at the 3 main seats. We then actually had to use his AVR's EQ to pull down at 20 Hz by -6dB to get a (+/-) 3dB final response from 5-100 Hz.

 

Now, let's assume that we wanted bang-for-buck or whatever the latest stated reason is to go ported instead. The general thought, or parroted opinion, is that one would want more output per driver at 15-25 Hz because it's cheaper and anything below that is a non event. Never mind that the size and complexity of the build increases and that the idea that <20 Hz (or whatever arbitrary frequency) being a non event is hogwash, let's see what would have been different for Adam:

 

Here is the estimated response of a ported version tuned to around 18 Hz without injecting the PEQ vs the actual sealed & signal shaped Raptor system.

 

 

In the stock situation of a noob building the ported version, no measurements would be taken. Would the ported version sound different than the EQ'd sealed version? Duh. Is it better? That's the question and to me it certainly would not. Would I miss the <15 Hz content? There is absolutely zero question about that. Of course I would and so would anyone else.

 

Again, if certain content with effects centered at 18 Hz were played, the ported version will clock +8dB higher dBSPL, but the presentation will be grossly distorted from what was actually mixed. Loud vs accurate. If loud is the goal, multiples solve that. Adam can push the SW trim levels to +15dB over reference with no problem. If 1/2 the system were used, he could "only" push it to around +8dB over reference.

 

So going from 4x15" sealed with 8KW burst power to 2x15" ported with 3KW burst power he would have 8dB more output at 18 Hz but lose 2 octaves of bandwidth and triple enclosure size to save $1,000.00, based on a typical black box DIY system in each case. That's all well and good but that's the difference, less all of the "velocity of air", "tactile feel", "<18 Hz is nothing", "99% of content", "99% of people", etc baloney.

 

I never bothered to mess with the ported version of the BHT-15 driver but I did with Blackbird and actually built and tested the ported version of the original BB driver. BB is 2x15" in 3.5 cubes and the ported sub was 1X15" in 7 cubes. IOW, as I've said many times, halve the box, add a driver and double the power when going from ported to sealed.

 

Here's the result, after using EQ to pull the hump in FR at the seats at the ported sub's tune (because that hump at 18 Hz sounds like butt to me), playing a scene from WOTW. IOW, both responses are identical except for the roll off below tune of the ported sub. Watch the low end disappear.

 

 

Of course, the ported sub will "go louder" at 18 Hz by xdB, depending on the design and build quality of the box, but, why would you need that? It's just a distortion of the content. Just as those who say <15 Hz does nothing for them, I say bumping 15-25 Hz does nothing for me, especially when the price is erasure of 2 octaves.

 

notnyt posted a sine wave at 10 Hz at 130dB through his sealed system. Supposing that was an actual calibrated measurement, one can assume that the result at 15 Hz would be 136dB with a similar low THD result. So, his ported version is claimed to be capable of +15dB at 15 Hz. So flippin' what? There is no content in existence that requires 136dB at 15 Hz even running the MVL and SW trim and amplifier gain at full open with a disc that's encoded as hot as the format allows. And, if the disc is encoded as hot as the format allows, bumping the SW trim and MVL full open will either be grossly clipping or internally compressed.

 

Adam can chime in as to whether or not 5-15 Hz adds anything to the presentation in his basement HT on a concrete slab when watching the Hulk vs Abomination fight scene and others like it. I've conducted the tests many times. Concrete, wood or steel frame floor, matters not. The content is there, it's intended to be there and it matters.

 

Adam could also up the VPL on the A14K, leave the 18 Hz peak in his in-room response and dial in a 10 Hz HPF and play the system as hot as the upstream hardware allows for without danger of over excursion. So what? He clocks a higher number with the rs meter by chopping out 2 octaves of content?

 

I'd love to see some of the ported proponents post their mic'd speclab versions of these sorts of scenes at their seats with whatever ported subs are supposed to be the good sort. You know, some data to back the rhetoric. Haven't we moved past WinISD models from LTD (who has never heard a sub, sealed or ported) with the associated falsehoods about content and it's perception?

 

Resonant systems shape the response by affecting a resonant peak. They do so more efficiently than shaping the signal with the added power on tap, but so what? Directly comparing naked responses with no signal shaping on the sealed system and no knowledge of whether the system itself rolls off at 15 Hz or 3 Hz before the amplifier is not comparing sealed to ported.

 

Properly executed, there is no other way to get full bandwidth reproduction from a subwoofer than sealed. Every other method is a compromise. Not much else you can say on the subject.

[theJman]

A friend pinged me with a link to a thread at AVS with the age-old "Ported or Sealed?" question, wherein my name was mentioned.

 

I'm really as burned out on that question as is possible and glad I'm away from AVS for that and similar reasons.

 

Those discussions are always only about peak dBSPL and nothing else.

 

Wait, you mean total SPL is not the holy grail?  Wow, have I ever been chasing my tail...

[Madaeel]

Honestly before you sold me the system I had my doubts about going sealed. I obviously never heard a system of this caliber in my room so I was skeptical of how it would sound and feel. We like the way the bass *feels* on our body and the sensations it gives us. That is  Ethan had his eD A7s-450 firing directly into the couch at his house so of course you could feel it but knowing my subs would be 10ft from me I was worried. Actually that's the main reason I bought the SI's and stacked them 3ft from the couch. Shoulda saved my money...

 

Remember when we first fired up TDK? Man I was nervous when I didn't feel anything. At that point of course we were running the system flat and IIRC around 10db from reference. Well after one of us walked over and saw the drivers weren't even moving and we bumped the trim I knew I had been nervous for no reason. I easily felt the note from the Batcycle and knew I made the right decision.

 

If your room is bigger than 5k cubes and you don't have the money for multiple sealed subs I can understand going ported. You could build a couple THT's or LLT's and have some pretty good output. With drivers like the SI's though it still wouldn't be much less money, and as you always mention you would miss the first 2-3 octaves. Having said that I do understand it for monetary reasons since there's plenty of people who simply can't afford to spend more than they've budgeted and to them $500 for one sub is a lot of money.

 

I'm just as confused as you by those who go ported for 130db+ capability though. Not only is it not ever needed in a soundtrack but even from 15hz up I would be scared for my house at those levels. The Raptors can easily do that but I never run music that loud for and movies are just peaks. Even those peaks at the levels I run at are scary.

 

If it's simply for a tactile sensation, which I completely understand, I still don't see how you can't feel the waves hitting your couch regardless of what alignment you have?? Unless it's a concrete block you should feel something! Even a properly powered sealed systen with enough displacement can do 20hz and down with authority. I see people with ported AND sealed systems on concrete using buttkickers/shakers or whatever the heck you wanna call them and I don't get it. I know my floor won't give me the sensation I'll get on a suspended floor but I don't even miss it. WotW and TIH in my room feel like an earthquake. It makes you scared to sit in the room and often people I have over usually say "oh shit!" along with some genuine fear in their faces haha.

 

So far I've had roughly ten people over to hear the system. Each one could tell the difference between the scenes I played. I have scenes that are centered at 30hz, 20hz, 16hz, 13hz, 10hz, and 7hz. It's very easy to tell in my room. The 7hz was obviously the most subtle, but my roll-off was the main culprit in that, and you can still feel it and its an eerie feeling.

 

I will never forget when I played Tron and Jazzy, who had never seen it, said something was worng when the scene was done playing.....what was "wrong" was I had the 18hz HPF engaged. For someone who knows nothing about subs to realize that definitely says something about the difference the low frequencies make. A HUGE one.

 

The *entire* Hulk vs Abomination scene is absolutely ridculous on my Raptor system. My favorite is when he falls to the ground which is strong to 5hz and when he punches Abomination into the ground the 10hz effect is amazing. Literally though that entire scene has so much content below 15hz. I know that's why Max said it's still his movie he judges all others by. With an 18hz tune it just wouldn't be the same.

 

All I know is if you need more output and/or tactile sensation the easiest thing to do is go nearfield which many have done. Unless it's for finanical reasons I would never go ported. When you experience full bandwidth it's an eye opening experience and something I will never give up.

 

My only regret is not having a room that warranted a Condor system.

 

[nube]

I had the (mis)fortune of being 100ft from a Blackhawk chopper the other day as it was spinning up and taking off from a movie set.  While it was loud, the thing that was shocking was the absolute pounding it gave to the ground and everyone around. 

 

Those 6-7Hz frequencies in BHD F'ing Irene, and the really long one in Lone Survivor, are completely legit, and it's terribly important for me to be able to hit them in my HT, but you'd pop the brown note if you reproduced them at the levels at home that they're reproduced in real life.  The same goes for explosions, especially if anyone's ever viewed in person the sustained ones produced by shuttle/rocket launches. 

 

When played back on a capable sealed system matched to its room, there's a sense of realism imparted via unfiltered movie mixes which you simply cannot achieve with ported systems (unless you go ultra huge 500 cubes ported for 5.4Hz tuning or whatever MKTheater is doing these days ).  That's the use case where sealed totally makes sense, and I'm glad you helped me see the light a few years ago, Dave.  This is also why we bitch and moan so much about filtered mixes - they cut out the things that are present in real life, or would be if what was on screen was real - and it impacts the immersion we get from a HT experience.

 

Similarly, I can appreciate budgets, lack of DIY skills/tools/time, or a desire to mostly listen to music which would lead folks ported.  I really don't care what type of systems people use, as long as they enjoy the presentation.

 

P.S.  Dave, get back to me about amp options when you can.  I now have income.

[maxmercy]

Having fast-roped out of BlackHawks and CH53's, I can tell you no HT can match what you feel when you are near/in/getting out of one of those things, and the Ospreys must be even louder/lower.  One of the best ULF moments in real life is any time an old UH-1 helo goes by, as you can tell it is coming from miles away due to the thump-thump-thump its 2-bladed rotor makes, and the Super Cobra to a lesser extent.  All ULF and midbass slam, from over 1/2 mile away.

 

What film set was this for?

 

Bosso, haven't you heard?  LOUDAH IS BETTAH!!!  I recently made the mistake of posting on AVS, and I was immediately reminded as to why I don't post there anymore, except to follow PI's sealed sub build....can't remember who it was, but they were stating that they always watch at +10dBRef minimum, with +10dB subwoofer trim on top of that, minimum.  That would mean 148dB theoretical peaks, and I'm not sure anyone's theater is that capable, but who knows...

 

As a super-system-test, I am still working on a test disc that includes tonebursts down to 1.5Hz, all channels driven in 7.1 at 0dBFs.  It is a true test of any system's headroom and freq response.  More on that later.

 

JSS

[MKtheater]

My wall ended up having a very low tune due to me not sealing up the speakers properly. It basically added a LT with no extra power needed but the trade off is a faster roll off after 4hz. I figure that is where my signal chain drops anyways so just leave it. There are no ports in my wall. The accurate and realism is what I like about the single digits because when you fell a 30hz blast with 5-10hz it just feels right! Dave hit the nail on the head when he said comparing sealed to ported is not accurate unless the sealed has the proper LT in place. I also have been arguing that if one has 8x18 or mucho displacement all they have to do to compare to a horn or ported is to apply a HPF at 18hz and let me know which one has more output. This was when I was trying to compare dual OS's to pop's 16x18 system and they were saying it was close in max output. I also reminded them that the OS to play max SPL is only within 30-60hz and everything below would be compressed significantly. what should have been an eye opener to all to see was when Luke took a video of his GH's pounding EOT. Just watch and listen to the 10hz tone, he registers the same SPL but the meter shows 32hz! It was all or 100% distortion playing and the sound changed. I know Luke knows it was distortion but how many think a GH will now play 128dBs at 10hz! Again, the 10hz was never reproduced, the harmonics were.

[lukeamdman]

My wall ended up having a very low tune due to me not sealing up the speakers properly. It basically added a LT with no extra power needed but the trade off is a faster roll off after 4hz. I figure that is where my signal chain drops anyways so just leave it. There are no ports in my wall. The accurate and realism is what I like about the single digits because when you fell a 30hz blast with 5-10hz it just feels right! Dave hit the nail on the head when he said comparing sealed to ported is not accurate unless the sealed has the proper LT in place. I also have been arguing that if one has 8x18 or mucho displacement all they have to do to compare to a horn or ported is to apply a HPF at 18hz and let me know which one has more output. This was when I was trying to compare dual OS's to pop's 16x18 system and they were saying it was close in max output. I also reminded them that the OS to play max SPL is only within 30-60hz and everything below would be compressed significantly. what should have been an eye opener to all to see was when Luke took a video of his GH's pounding EOT. Just watch and listen to the 10hz tone, he registers the same SPL but the meter shows 32hz! It was all or 100% distortion playing and the sound changed. I know Luke knows it was distortion but how many think a GH will now play 128dBs at 10hz! Again, the 10hz was never reproduced, the harmonics were.

 

Wrong...

 

I guess I need to clarify the EXACT same thing I did on AVS about the 10hz portion...

 

Here's the EOT scene with just the Ghorns playing.  Notice there's nothing audible whatsoever during the 10hz portion, and the SPL Lab measures nothing at 10hz or 32hz:

 

 

 

 

That 30hz during the 10hz portion only shows up when the Othorns are on, and that's because on the Blu-ray recording, during the 10hz portion there's also 30hz present:

 

[MKtheater]

I stand corrected. I remember you saying that too. the GH would still play the harmonics at 100% if you tried but it was no made for 10hz. I also know you had a HP filter at 13hz. The different tone is a different sub then?

[lukeamdman]

I stand corrected. I remember you saying that too. the GH would still play the harmonics at 100% if you tried but it was no made for 10hz. I also know you had a HP filter at 13hz. The different tone is a different sub then?

 

Yes, with the video of both playing you'll hear that weird tone during the 10hz portion.  It's 30hz, 50hz, and 70hz all playing at a lower level...  

 

Honestly, with 30hz and up enabled, I don't think this "demo" sounds all that great because of everything else mixed in.  I think it sounds great when 30hz and up are filtered out!

[Bossobass Dave]

Hi Luke,

 

But the title of the vid is "GHorns at 136.4dB at 20 Hz". It's actually 20+60+100 Hz with no simple way to extract 20 Hz from the total dBSPL.

 

I'm confused as to how the measurement works, as it appears to only capture a single frequency?

 

And, why doesn't the Ghorn show 30 Hz output during the 10 Hz fundamental? (Maybe the answer is the same as the answer would be to the first Q)

 

Can you mic that scene through SpecLab? Or, post a file of the audio and I'll SL it? The camera mic is useless.

[MKtheater]

He has a 22 hz LPF on the GH's I believe. Luke I know you posted on the other thread thinking I was starting trouble but it was a misunderstanding with no ill will. The GH's would produce the harmonics much louder than the fundamental at 10hz if you let it but like I said you know that and why you have it setup the way you do, I would think.