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This a recording specifically designed to test impact/punch. It has an extremely high crest factor. If it doesn't punch and slam you've got problems.

Yep, but this one is even more intense, especially as the song goes on... (especially the FLAC version. Not YT version.)

It's the audiophile-dynamics equivalent of Bass I Love You. /forum/images/smilies/biggrin.gif
Totally. I remember seeing that on some vid where they were comparing a pair of speakers with some 12s to a live orchestra. The speakers were distorting on the bass and didn't sound realistic as I recall.
 

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Back in the '80s, I had a Marantz system claiming THD of .008% at rated power of 250 W/ch, or some such. To test this, I muted it, then turned it all the way up. I then hit play on The Police's Roxanne and un-muted it. It felt like the Hulk was giving me CPR chest compressions. Of course, I had to stop before the windows broke, but I've never felt anything like it since.

I'd say SPL and content has a lot to do with it.
 

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So I’m traveling on vacation this past week and next but I’ve been pondering my next steps in subwoofer world. Thanks to folks here I have my current setup working fine, but it’s missing something, the thing that 50% of the people here seem to chase - chest slam. I’ve got
 

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Discussion Starter #66
I have JBL 3677 as LCR paired with a JTR S1 and UM18 (both sealed design), crossed at 80Hz for sub duty. That's 3 x 15" and 2 x 18" and I still missed the midbass kick produced by a single Ken Kreisel 12012 I owned before. EQ didn't solve my problems too.

I decided to invest $90 on a PA460 and dropped it into a 3 cu ft sealed box with advice from forum member rhodesj. That small investment paid off the moment I dialed in the phase and delay. I don't know the science behind, will not attempt to explain as I'm sure other members have the knowledge :) Just sharing my experience as I was in a similar situation before. Hope you get that kick to your chest real soon with the PAs.

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Thanks for sharing. How big is your room and how far away did you end up placing the single pa460 from your main seating position?
 

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Thanks for sharing. How big is your room and how far away did you end up placing the single pa460 from your main seating position?
My system is in the hall, approximately 14ft x 21ft. The Dayton is about 5ft away. It is critical to have the subs time aligned. If your UM is ported, check out the VBSS thread that is designed to optimise the PA460.

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Well I am back to AVS Forum to research my next build for this very reason. Years ago I had Harmon/Kardon setup with a dedicated 200w amp for the mains. The speakers were DCM's with 2 12" woofers per cab. The chest thump was phenomenal. Then I got married and the wife insisted a downsize in speaker size. Since then I have been thru about 7 different sound systems and setups. I have even done major house remodeling for speaker placement/inconspicuous for WAF. I no doubt have/had systems that extend far lower with more SPL and still lack the chest thump of my HK-DCM setup. The closest that I have came near is with a 36" BFM THT Sub with a 120hz crossover. I currently run dual 460RS in sealed enclosures and have fantastic base that I feel in my whole body but still don't have the chest thump from the kick drum in my music. I am considering DIYSG 1299's in a ported build with a low xcross over to the subs. Probably do new subs with the 1299's, considering a IB setup or a large horn down firing thru ceiling.
 

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How to increase chest punch: opening your mouth, and other findings

Bass: the Physical Sensation of Sound
Useless.

First, it should be stressed that these results were not captured in an exacting laboratory setting...

…the SPL meter used loses precision below 31 Hz, so the output recorded...is not reliable...

...Furthermore, many of the test subjects had imbibed a few beers by the time testing began, so it is difficult to determine how much of the vibrotactile sensation was due to the test tones and how much was due to alcohol...
 

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Think about the systems you've heard that have had great chest slam. For me they have all been PA. The gentlemen above who suggested that you explore pa gear was spot on. You need efficiency. A low sensitivity sub driver in a vented enclosure has to move a long way to make much spl, that movement takes time. Percussive slam has to be fast. If you search diy pa forums I bet you will find more on chest slam. Long story short, you want a horn subwoofer down to 30 or 40 Hz then run vented infrasub and or bass shakers under that. Check out the "tuba ht", I've never heard it, but others descriptions say it hits very hard. I am currently building a 30hz front horn, but it's still in prototype. 30x30x60. The tuba is much smaller but less sensitive. Good luck! Craig
 

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If a lower efficiency driver took significantly longer to move to achieve a 100hz transient, that would be easily measurable as a form of distortion. So what you are saying is PA equipment generally has less distortion in the bass region - i dont agree with that at all.

Its spl. Ive never experienced chest slam at low spl. PA equipment used at concerts, parties, clubs, etc are typically played at much higher levels than one would comfortably listen at in their home.
 

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If a lower efficiency driver took significantly longer to move to achieve a 100hz transient, that would be easily measurable as a form of distortion. So what you are saying is PA equipment generally has less distortion in the bass region - i dont agree with that at all.

Its spl. Ive never experienced chest slam at low spl. PA equipment used at concerts, parties, clubs, etc are typically played at much higher levels than one would comfortably listen at in their home.
I watched Hitchikers Guide to the Galaxy last night for the first time in years, first time on a good system since the theater.

My near fields gave off huge slam and punch during all the ship sounds at about -9db from reference. My near fields are calibrated the same as the farfield subs (spl) and no doubt the nearfield is what gave the most feel. SPL is absolutely required but proximity to the moving air, without a doubt has dramatic effects. I can get the same feel from the other subs with a lot more spl....thus I have to conclude its spl and/or proximity to the airflow. Thoughts?
 

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I watched Hitchikers Guide to the Galaxy last night for the first time in years, first time on a good system since the theater.

My near fields gave off huge slam and punch during all the ship sounds at about -9db from reference. My near fields are calibrated the same as the farfield subs (spl) and no doubt the nearfield is what gave the most feel. SPL is absolutely required but proximity to the moving air, without a doubt has dramatic effects. I can get the same feel from the other subs with a lot more spl....thus I have to conclude its spl and/or proximity to the airflow. Thoughts?
Ported subs, right?

Because if sealed, closer proximity just takes us back to SPL. But ported subs actually send some air out the port, giving them a different effect.
 

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Discussion Starter #75
I built two ported enclosures from the design here:
https://www.avsforum.com/forum/155-diy-speakers-subs/2643073-slot-ported-nearfield-mbm-w-pa460.html


Am going to integrate and try them by my screen wall and see if I can get the chest slam from that distance at more moderate spl (doubtful). If that doesn’t work, will see if I can get it nearfield at more moderate spl (am hopeful I can based on others comments on the forums). Issue is I want chest slam without needing to always be at reference levels, even if that means ‘cheating’ with nearfield subs. If it works better nearfield, I’ll likely keep them there and build 2 more to sit behind the screen to keep the sound more directionally balanced since I’m hoping to cross these as high as possible with my mains (htm12s).

Have 2 UXLs and 2 um18s, all ported, for
 

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If a lower efficiency driver took significantly longer to move to achieve a 100hz transient, that would be easily measurable as a form of distortion. So what you are saying is PA equipment generally has less distortion in the bass region - i dont agree with that at all.

Its spl. Ive never experienced chest slam at low spl. PA equipment used at concerts, parties, clubs, etc are typically played at much higher levels than one would comfortably listen at in their home.

I hadn't considered that. What type of distortion do you think this would be? Definitely not harmonic, perhaps something in the impulse response I'm not aware of?

I
 

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I hadn't considered that. What type of distortion do you think this would be? Definitely not harmonic, perhaps something in the impulse response I'm not aware of?

I
Think about it this way: if Driver B took significantly longer than Driver A (of the same size) to produce a 100Hz tone, it wouldn't be producing a 100Hz tone.
It's like the difference between speed and acceleration and jerk (the derivative of acceleration). Different cars can go 10mph, but the getting there feels different. I believe that if 100hz ac is going through the voice coil it will make a 100hz tone. If the cone is heavy like most inefficient sub drivers, it seems like it's ability to launch a transient impulse should be inferior. I guess the proof is in the reality. We've all heard crazy loud systems with no chest slam, obviously there are other factors.
 

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It is fair to say that my thoughts were only a guess. Think about the first time you heard a rim shot through a large electrostatic speaker. It's startling in how much snap there is. Very similar to chest slam but at a higher frequency. That phenomenon cannot be explained by spl, and no loudspeaker measurement can quantify it. There is an aspect of "subjective speed" that we can't measure and don't understand. That's all I have to say about that.
 
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