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Old 01-29-2016, 11:43 PM
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Originally Posted by bgtighe23 View Post
So true. Based on this chart, I'm beating out dual SVS SB Ultras. Which is over 2.5 times the cost. And 18" drivers look so much better than 13.5" drivers

I felt bad when I had to return both of my SVS subs back to SVS and they asked me why...well DIY beat the poop out of them.

Who needs 4K?... just go see your optometrist.
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Old 01-30-2016, 05:42 AM
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I felt bad when I had to return both of my SVS subs back to SVS and they asked me why...well DIY beat the poop out of them.
HA. I sort of did. I was just hoping for a little more sub for the money I was spending.

When I called them to ask for an RA as well, and I was asked why I wasn't satisfied. I told them I decided to go DIY to maximize my price to performance. The person I spoke with attitude never changed throughout the conversation which was nice. We spoke for about another 5 minutes on random sub stuff and seemed to hang up on a good note.

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Front Stage : Martin Logan Motion 60XTs/Elac Debut F5 Center
Surround Speakers : HTD Level 3 Towers/RBH R5Bi Front and Rear Heights
Subwooferage : Dual UM-18s/6 SI HT18s
Born in 1995 and still continuing my HT journey

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Old 01-30-2016, 12:49 PM
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Originally Posted by bgtighe23 View Post
HA. I sort of did. I was just hoping for a little more sub for the money I was spending.

When I called them to ask for an RA as well, and I was asked why I wasn't satisfied. I told them I decided to go DIY to maximize my price to performance. The person I spoke with attitude never changed throughout the conversation which was nice. We spoke for about another 5 minutes on random sub stuff and seemed to hang up on a good note.

Yeah I was satisfied with the SVS, but the guy in me said WHAT IF...I could go louder, researched and DIY popped up

Who needs 4K?... just go see your optometrist.
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Old 01-30-2016, 01:46 PM
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Yeah I was satisfied with the SVS, but the guy in me said WHAT IF...I could go louder, researched and DIY popped up
I've known about DIY kits before I purchased the SB-2000s, but always doubted myself and figured it would be too difficult and I wouldn't be able to finish it.

Once I fired up the SB-2000s, I said forget it. I'm trying out UM-18s instead. They better be a huge upgrade

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Old 01-31-2016, 10:09 AM - Thread Starter
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Originally Posted by MKtheater View Post
WTH did I just do! I still have to measure but I am going to destroy my house. I just ported all my subs. Still flat to 5hz in room but big peak at 8-10hz, more info coming. It produces 130 dB at 10hz, 130.5 at 12.5, 131 at 16hz and 132 at 20hz from the sims.
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No, I tried porting the fi drivers which did not work as they are pure IB drivers, these are very different. I only gain from 6-25hz and lose below 6hz. I want to try lone survivor and see what happens.
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Well, so what happened?
Wellllll, what's the story?

Can you post the sim against the SI sim?

I'm hopeful to be getting an update to the ULF lists soon. MK, and anyone else that needs an update, please post your new ULF Card.
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Old 01-31-2016, 06:56 PM
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Well, it is good to see you Dom. I hope all has been well and you have had some time for yourself to have a little fun.
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Old 02-01-2016, 09:42 AM
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Here is the sim



Marantz 7702 Atmos
3 Inuke NU4-6000 amps for all speakers.
Speakers- 7 Behringer B215XL's, 4 212xl's for ceiling speakers.
Front subs 8 SI 18ht ported SLLT powered by Peavy IPR 7500
Rear subs 4 SI 18HT ported SLLT powered by Inuke 6000.
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Old 02-01-2016, 09:52 AM - Thread Starter
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Originally Posted by MKtheater View Post
Here is the sim


Can you put the si sim in there?
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Old 02-01-2016, 12:57 PM
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Marantz 7702 Atmos
3 Inuke NU4-6000 amps for all speakers.
Speakers- 7 Behringer B215XL's, 4 212xl's for ceiling speakers.
Front subs 8 SI 18ht ported SLLT powered by Peavy IPR 7500
Rear subs 4 SI 18HT ported SLLT powered by Inuke 6000.
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Old 02-01-2016, 12:58 PM
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How can I make that full size?

Marantz 7702 Atmos
3 Inuke NU4-6000 amps for all speakers.
Speakers- 7 Behringer B215XL's, 4 212xl's for ceiling speakers.
Front subs 8 SI 18ht ported SLLT powered by Peavy IPR 7500
Rear subs 4 SI 18HT ported SLLT powered by Inuke 6000.
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Old 02-02-2016, 05:44 PM - Thread Starter
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Old 02-02-2016, 05:49 PM - Thread Starter
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Well, it is good to see you Dom. I hope all has been well and you have had some time for yourself to have a little fun.
Thanks DJ!

Been super busy with non-AVS stuff unfortunately...still lurking of course.

I do want to update the spreadsheet and lists, and have some more tests planned to continue to prove out the PVL theory, specifically with ported vs sealed tactile response difference in Post 4 and Post 5.
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Old 02-02-2016, 07:43 PM
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Hey Dom, the biggest difference is I can play it even louder without tripping any breakers. It feels more violent but the proof will come in spec lab graphs. I was experiencing my IB with Audyssey XT32 and without and I will show the differences on a very low scene, BEQ of my matrix from Tfransformers 2. I actually have more 3-9 hz with Audyssey engaged and more mid bass as well. Without Audyssey I have more 9-20hz and slightly less 3-9 hz and less midbass and it feels stronger. That 9-20hz sure packs a wallop. This ported system boosts that same region and in my small room still flat to 5hz. I would never port to lose under 10hz though. You need to visit again as I now have Atmos going and it sounds awesome! I like this setup much more than the last you heard, by a huge margin.
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Old 02-02-2016, 07:45 PM
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Oh yeah, I have a friend coming over to take a 3D pic or something after we put up the 24 panels. I have not shown the berries in wall yet.
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Old 02-03-2016, 08:16 AM
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Oh yeah, I have a friend coming over to take a 3D pic or something after we put up the 24 panels. I have not shown the berries in wall yet.
Do you have a build thread or thread that you post your pictures to? I've only read about your setup and seen the short clips of your IB subs.

Congrats on the Atmos, btw.

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Old 02-03-2016, 10:01 AM
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I post so much I can't even remember. I will post pics in the Behringer thread. I think I started a thread for my SIs so I will dig it up and post pics there too.
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Old 02-04-2016, 09:32 AM - Thread Starter
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Hey Dom, the biggest difference is I can play it even louder without tripping any breakers. It feels more violent but the proof will come in spec lab graphs. I was experiencing my IB with Audyssey XT32 and without and I will show the differences on a very low scene, BEQ of my matrix from Tfransformers 2. I actually have more 3-9 hz with Audyssey engaged and more mid bass as well. Without Audyssey I have more 9-20hz and slightly less 3-9 hz and less midbass and it feels stronger. That 9-20hz sure packs a wallop. This ported system boosts that same region and in my small room still flat to 5hz. I would never port to lose under 10hz though. You need to visit again as I now have Atmos going and it sounds awesome! I like this setup much more than the last you heard, by a huge margin.
Damn....I may have to make that trip! You're right, you literally have a completely different setup since last I went...nearfield, ported, atmos...the whole thing!

So, do you think it's more violent even at the same levels as sealed? Part of my PVL theory is that the port induces more particle velocity near tune, increasing sound intensity, and thus more tactile response.

Oh, and feel free to post pictures of your setup here...this thread needs some life.
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Old 02-04-2016, 02:15 PM
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I will, my friend came over to start the panels and we ended up making steel stands for all my speakers so they don't move. They are pretty sweet but I am back top square one! It is more violent and still deep. I have to love my giant enclosures, it lets me do anything and when I get bored I can seal them up again.

Marantz 7702 Atmos
3 Inuke NU4-6000 amps for all speakers.
Speakers- 7 Behringer B215XL's, 4 212xl's for ceiling speakers.
Front subs 8 SI 18ht ported SLLT powered by Peavy IPR 7500
Rear subs 4 SI 18HT ported SLLT powered by Inuke 6000.
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Old 02-04-2016, 06:09 PM
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On the PVL theory, the vibsensor thread should show some trending on sealed vs ported once there is enough data. Ports in the nearfiled produce more air at tuning and should result in a greater TR. I recently did a total layout change of the room after adding a projector and have a somewhat nearfield rear array of ported sub. The res to the subs are around the room. Two things resulted: Nice FR and brutal TR.

Every since I joined this thread, it has done nothing but, cost me to spend more money, lol.
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Old 02-04-2016, 06:48 PM - Thread Starter
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Originally Posted by derrickdj1 View Post
On the PVL theory, the vibsensor thread should show some trending on sealed vs ported once there is enough data. Ports in the nearfiled produce more air at tuning and should result in a greater TR. I recently did a total layout change of the room after adding a projector and have a somewhat nearfield rear array of ported sub. The res to the subs are around the room. Two things resulted: Nice FR and brutal TR.

Every since I joined this thread, it has done nothing but, cost me to spend more money, lol.
Lol, but look at the ULF masterpiece of an HT room you have!

The only way the vibsensor thread will show prove that is if someone does a direct comparison within their own room. Comparisons across different room introduce to many variables (furniture, floor, sub, etc.) to adequately compare, IMO.

Also, I don't think the air of the port is contributing anything to the shaking...take a blow dryer on high and point it at the back of your couch...it's not going to shake the couch at all.

OTH, perhaps its the frequency of the air that shakes it? IOW, if you took a blow dryer and turned it on and off 15 times per second (15hz), would it shake the couch? I still don't think so...I think it's the additional PVL being produced...

Thoughts?
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Old 02-04-2016, 07:44 PM
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I am lost when it comes to that! I just know I have full band, high Spl, and lots of shaking. Too much shaking becomes artificial feeling and when the shaking is accompanied with the pressure and weight I know it is a good thing. I know my room helps me a ton being so sealed and with low ceilings which act like another boundary!
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Old 02-04-2016, 08:09 PM
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I have the full and Mini Marty's, the dual box UM 18's, and dual box SI HT. If I remeber the spl number should be fairly similar to around 15 or 16 Hz of one of the dual boxes compared to a Mini Marty. If this is so, I may be able to compare the two. The two subs are not exactly equal but, may be close enough to show a trend. I need to do a little research.
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Old 02-06-2016, 10:52 PM
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Originally Posted by dominguez1 View Post
Lol, but look at the ULF masterpiece of an HT room you have!

The only way the vibsensor thread will show prove that is if someone does a direct comparison within their own room. Comparisons across different room introduce to many variables (furniture, floor, sub, etc.) to adequately compare, IMO.

Also, I don't think the air of the port is contributing anything to the shaking...take a blow dryer on high and point it at the back of your couch...it's not going to shake the couch at all.

OTH, perhaps its the frequency of the air that shakes it? IOW, if you took a blow dryer and turned it on and off 15 times per second (15hz), would it shake the couch? I still don't think so...I think it's the additional PVL being produced...

Thoughts?
Greetings Fellas. Winter hibernation is almost over and its time to get back to business here. Will finally have my front array up and running again and ready to fire up another round of testing.

Just a few comments concerning using VS. While there is variables, clear patterns have been established concerning Vented, Sealed, IB's and other designs. Actually the air from the port is the primary contributing factor to the TR in a vented system. But its relatively narrow band at peak TR(15-25hz), as well as being a typical cabbed speaker above and boxless (free air) below tune. The driver is damped at the tune, do to the resonator loading it, then it unloads below the tune. You referred to this effect Dom, when you moved your Vented subs to the rear, with a corresponding increase in TR.
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Old 02-08-2016, 03:47 AM
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I finally got my room put back together and hopefully will be able to do some more Vibsenor testing. I went with the array approach so, I expect for this will change the TR. Maybe this time I can get some good phone data, lol.
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Old 02-08-2016, 03:00 PM - Thread Starter
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Greetings Fellas. Winter hibernation is almost over and its time to get back to business here. Will finally have my front array up and running again and ready to fire up another round of testing.

Just a few comments concerning using VS. While there is variables, clear patterns have been established concerning Vented, Sealed, IB's and other designs. Actually the air from the port is the primary contributing factor to the TR in a vented system. But its relatively narrow band at peak TR(15-25hz), as well as being a typical cabbed speaker above and boxless (free air) below tune. The driver is damped at the tune, do to the resonator loading it, then it unloads below the tune. You referred to this effect Dom, when you moved your Vented subs to the rear, with a corresponding increase in TR.
That's cool if you have vibsensor data that shows the impact of different designs...do you have enough data to see trends in the different alignments?

Regarding the port air:

I still don't believe it's the air causing the tactile response. I believe the sound wave is displacing the air molecules (causing 'wind'), but the particle velocity along the wave is what causes the tactile response. The air is just a side effect. Going back to my hair dryer analogy, I don't believe turning on a hair dryer on and off 15 times a second would cause a 200lb couch to shake....there is no sound wave (like a sub) that's being produced from the dryer, and thus wouldn't move the couch.

Air is not going to excite any resonant frequencies in the couch.

Does that make sense?
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Old 02-09-2016, 06:28 PM
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^ That's a great analogy, makes sense when you put it that way.

HT: PSA dual V3600's - PSA MTM-210T L/R - PSA MTM-210 Center- PSA 110sr Surrounds - Denon X4200 - Sony BDP-S5200 - Panamax M4300 - Direct TV - Apple TV - Xbox360
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Old 02-09-2016, 09:48 PM
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That's cool if you have vibsensor data that shows the impact of different designs...do you have enough data to see trends in the different alignments?

Regarding the port air:

I still don't believe it's the air causing the tactile response. I believe the sound wave is displacing the air molecules (causing 'wind'), but the particle velocity along the wave is what causes the tactile response. The air is just a side effect. Going back to my hair dryer analogy, I don't believe turning on a hair dryer on and off 15 times a second would cause a 200lb couch to shake....there is no sound wave (like a sub) that's being produced from the dryer, and thus wouldn't move the couch.

Air is not going to excite any resonant frequencies in the couch.

Does that make sense?
The blow dryer just blows air. A port works differently. There's no pressure variation like theres is with a vented box. Here's some info from wikipedia that explains whats happening in detail.

Helmholtz described in his 1862 book, "On the Sensations of Tone", an apparatus able to pick out specific frequencies from a complex sound. The Helmholtz resonator, as it is now called, consists of a rigid container of a known volume, nearly spherical in shape, with a small neck and hole in one end and a larger hole in the other end to admit the sound.

When the resonator's 'nipple' is placed inside one's ear, a specific frequency of the complex sound can be picked out and heard clearly. In Helmholtz’ book we read: When we “apply a resonator to the ear, most of the tones produced in the surrounding air will be considerably damped; but if the proper tone of the resonator is sounded, it brays into the ear most powerfully…. The proper tone of the resonator may even be sometimes heard cropping up in the whistling of the wind, the rattling of carriage wheels, the splashing of water.”

A set of varied size resonators was sold to be used as discrete acoustic filters for the spectral analysis of complex sounds. Picture: Resonator from Koenig's Acoustic Catalogue, 1889. Cost: 380 francs for a series of 14 resonators.

There is also an adjustable type, called a universal resonator, which consists of two cylinders, one inside the other, which can slide in or out to change the volume of the cavity over a continuous range. This type of resonator is in use in the Fourier analyzer, and is equivalent to tone variator in its function. <http://www.phys.cwru.edu/ccpi/Helmholtz_resonator.html> When air is forced into a cavity, the pressure inside increases. When the external force pushing the air into the cavity is removed, the higher-pressure air inside will flow out. Due to the inertia of the moving air the cavity will be left at a pressure slightly lower than the outside, causing air to be drawn back in. This process repeats, with the magnitude of the pressure oscillations increasing and decreasing asymptotically after the sound starts and stops.

The port (the neck of the chamber) is placed in the external meatus of the ear, allowing the experimenter to hear the sound and to determine its loudness. The resonant mass of air in the chamber is set in motion through the second hole, which is larger and doesn't have a neck.

A gastropod seashell can form a low Q Helmholtz resonator, resulting in the "sounds of the sea".

The term Helmholtz resonator is now more generally applied to include bottles from which sound is generated by blowing air across the mouth of the bottle. In this case the length and diameter of the bottle neck also contribute to the resonance frequency and its Q factor.

By one definition a Helmholtz resonator augments the amplitude of the vibratory motion of the enclosed air in a chamber by taking energy from sound waves passing in the surrounding air. In the other definition the sound waves are generated by a uniform stream of air flowing across the open top of an enclosed volume of air.
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Old 02-09-2016, 09:59 PM
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I finally got my room put back together and hopefully will be able to do some more Vibsenor testing. I went with the array approach so, I expect for this will change the TR. Maybe this time I can get some good phone data, lol.
I'll be watching.
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Old 02-10-2016, 05:59 AM - Thread Starter
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Thanks for the reference @coolrda . Sounds like we agree that it is not the air causing the tactile response, but rather the pressure wave from the port.

To that end, my hypothesis remains around a vented design having a greater tactile response around port tune (given the same spl as a sealed design), since both the port and the driver (albeit small) are producing pressure waves.

How can there be a different tactile response if the designs are producing the same spl? Answer: Greater Sound Intensity.

Sound Intensity(sil) = particle velocity (pvl) * sound pressure (spl)

If spl is kept constant, then the only way to achieve greater sound intensity (and resulting tactile response) is to have greater particle velocity (pvl).

Since the driver and port are producing pressure waves, the hypothesis is that the combination produces more particle velocity (pvl) than just the sealed driver alone.
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Old 02-10-2016, 07:13 AM
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Since the driver is barely moving at this point, isn't it more likely that a port produces greater pvl per SPL than a driver? If we assume the driver doesn't contribute in the ported system, you could test this by applying a bandpass filter to a sub so as to coerce it into the same FR as the port has alone. Compare the tr results when playing a sine wave (or noise band limited to the port output passband?) and see which one wins.
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