Sign in to follow this  
Followers 0
TTS56A

Bass punch threshold

107 posts in this topic

Hello men! I'd like to ask you what is the threshold for feeling bass frequencies (40-80 Hz range) in the cest like slam and punch. I found this is the frequency range wich has more tactile feedback. 

 


It says: At 116 dB(?) HUMAN BODY BEGINS TO PERCEIVE VIBRATION IN THE LOW FREQUENCIES.

 

But it doesn't explain if it is talking about dBA, dBC or what other kind of pondaration, because from A and C there is a difference of 30 dB at 50 Hz!! So if 116 dB is the right level, what is the ponderation and frequency range? Maybe 116 dBC at 80 Hz it's like 130 dBC at 20 Hz... I'd like to know it

 

I also heard talking about "sound intensity" wich take into account particle velocity. 

 

Thanks!  :)

Share this post


Link to post
Share on other sites

A lot of times those studies refer to dB SPL rather than any weighting. Refer to the Wikipedia page on sound pressure for more information there. Some studies do use weighting, and you have to look them up individually to see if that is the case. Audioholics published this article which has a similar list (although not as comprehensive) which arranges bass sensations by frequency rather than loudness. I don't think you need 116 dB to experience vibration. I think a lot of that has to do with individual's physique. The air in the lung cavity may have resonant frequencies based on the size of that individual's lungs which can make them more sensitive to vibrations at a certain frequencies. Body fat will also play a role, as fat will damp resonances. Sobriety level may also play a role. 

1 person likes this

Share this post


Link to post
Share on other sites

"The air in the lung cavity may have resonant frequencies based on the size of that individual's lungs which can make them more sensitive to vibrations at a certain frequencies. Body fat will also play a role, as fat will damp resonances. Sobriety level may also play a role."

 

That's very interestin! I'd like to deepen the discussion. Maybe there are some studies (books or pdf) wich i can learn more.. For example about sound intensity and the relationship between PVL and SPL.

Share this post


Link to post
Share on other sites

Tactile sensation definitely begins below 116 dB regardless of weighting method.  I think the rough threshold may be closer to 90 dB, depending on the content and such.  Of course, it depends a lot on the signal and may also depend a lot on the response of the system at the listening position.  Another complication is that vibrations in your furniture, either picked up from the floor or resonating with the air, may be transmitted directly to the body.  This phenomenon most certainly contributes tactile sensations at lower frequencies than one would probably otherwise feel.

 

It is my own experience that bass at and below 40 Hz is felt by the whole body.  Above 40 Hz, the tactile feelings seem to originate from within the torso.  The higher the frequency, the higher in the torso they are felt.  From 40-60 Hz or so, the feeling may be mostly in the abdomen.  From 60-120 Hz, the feelings are localized more in the sternum, and for 120 Hz up somewhere north of 200 Hz, the feelings are felt higher up in chest.  Of course, other people may have different impressions, and I'd also bet that women on average experience sensations at somewhat higher frequencies than men.

 

It is also my experience that I notice tactile sensations more readily with transient sounds than continuous sounds.  That may simply be due to transient sounds typically being at higher SPL (albeit briefly) than continuous sounds in actual content, but it may also be the case that the body resonances are low Q and are excited more readily by broadband sounds.  To the extent that this is the case, it may explain (at least partly) why home theater systems often lack in the "chest punch" area.  Systems in residential sized rooms tend to have the most inconsistent response in the 50-200 Hz region because of room resonances and SBIR effects.  For anyone who listens with speakers placed ~1-6 feet away from the front wall without sufficient acoustic treatment to absorb the frequencies that are affected by this reflection, there is likely to be one or more deep nulls in the direct part of the impulse response within this crucial frequency range.  This tends to spread transients out in time and may considerably reduce the impact felt from them.  It has been my own experience as I've made incremental improvements over time that the smoother my response over that range, the better my system punches.

 

I'm not aware of any formal studies linking sound intensity or PVL to tactile sensation, but a few people here have proposed this hypothesis.  I personally am skeptical that PVL or sound intensity explains this at all.  The human body is not porous, so no air actually passes through it into the chest cavity.  Energy is transferred when a difference in pressure between the outside and inside of the chest induces a force, and the force causes acceleration (a change in velocity over time) of the flesh.  Impedance is a measure of how pressure it takes to achieve a given PVL in a material.  Being dense and solid, flesh has a much higher impedance than air does, and this limits the transfer of energy from the air into the flesh.  For more efficient energy transfer, and as a consequence more tactile feel, the impedance of the air should match more closely to the impedance of the flesh.  In other words, for more energy transfer, the ratio of PVL / pressure for the air should be *decreased* (i.e., higher impedance in the air) as tends to happen when one is sitting near a wall or some other rigid boundary.  But this scenario is opposite to what is being argued by PVL proponents as being important for good tactile feel.  My guess is that near-field subs improve tactile response, not because of PVL, but because they interact with the room less and help fill in gaps in the frequency response.  Even if crossed at 80 Hz, subs may still contribute a lot of sound, relative to the mains, in the 80-200 Hz region, either because the mains have weak output in that region or because of deep room and/or SBIR nulls.

 

One more point that may or may not be relevant is inductance in the subs and/or mains.  Inductance in a woofer reduces high frequency output, increases distortion, and also contributes some phase shift.  Some people argue that subwoofer and/or mains with lower inductance have better punch, but I'm not entirely sure how important this is relative to smooth frequency response or if it's important at all.  I've definitely noticed more and better punch since upgrading my mains to AE TD12Ms with extraordinarily low inductance.  However, these woofers also have a lot more headroom than the woofers they replaced, and the interface between my new speakers and the front wall is *much* better as far as avoiding SBIR effects.  Indeed, the increased punch may simply be due to a big improvements in smoothness across the 100-300 Hz range.

4 people like this

Share this post


Link to post
Share on other sites

I agree with many of the points above, but also add that furniture resonance plays significantly into this.  A drum hit that excites the furniture you are sitting on or floor you are standing on will be 'more powerful'.  For a given SPL, SME is right, improving the 50-200Hz bandwidth and ETC/IR and reducing modal ringing will improve slam/punch (I have done this recently by adding plinth bass traps to my HT).  But you need SPL.  Lots of it.  And the right mix.

 

I will quote Ricci on the subject as well:

 

"Midbass...or bass punch or whatever...In my opinion it goes like this.

 

#1...Identify your reference. What exactly was the time/place/system that you so desperately want to recreate? For me and for so many others it is often a concert or many concerts or live events with huge stacks of very efficient speakers. For another smaller amount of people it may be a car audio system. Again probably multiple big sub drivers, lots of power and a very efficient space. Does anyone else's reference for a punchy bass system come from anywhere else? Mine is from both.

 

#2. Here's the thing. Most people think it is about the speakers or the amount of power. That's partly right. IMHO a very large chunk of it is sheer acoustic power and SPL. You will never get there at 95dB and you will never get there with two  6.5" midwoofers and a single 12" sub in a home. Car audio systems are very powerful. 140dB is easy. Instant face / chest/ gut slam. Big concert sub stack? The same thing. They run the subs really hot and 125dB peaks a few meters in front of the stack is no big deal. (They measure the system SPL with A weighting typically which is how you'll see things like 105dB when they were crushing the room with bass. Perfect for getting around noise ordinances.)

 

#3. What else do car audio and live rigs have in common? The content is different. Live sound has a mixer and microphones and it is not unheard of for the kick drum to be 20dB hotter than everything else in the mix. Instant punch if the rig can keep up. The cd, vinyl, radio or concert disc you will be throwing in simply will not be mixed anything like that. Car audio simply has the bass turned up a good 20dB from the rest of the mix. Often it is high passed and EQ'd into a pretty severe peak around 40-80Hz too. Flat calibrated playback of recorded media is never going to get the sound that was heard in either of these places.

 

To me it is these 3 things that cover 95% of it. Out of the 3 I actually think #3 has a huge bearing. The bass isn't hot enough relative to the rest of the bandwidth or the overall mix is completely different. Some people will say things like system integration, decay, phase response etc, which can help but it's really about the bass just being loud and the mix having it jacked way up in level.

 

that's my take on it."

 

A great mix that emphasizes drum hits:

 

http://www.demo-world.eu/2d-demo-trailers-hd/

 

Scroll down to the DTS Paint Symphony trailer.  Played back at Reference Level, if you do not experience some punch, you need to really look at your IR/ETC/modal ringing and make changes, or upgrade your components so that your system is not compressing at these levels (BIG CULPRIT ROBBING MANY OF SLAM).

 

Make no mistake.  Playback of this track at reference will tax your system.  You cannot do it justice with low sensitivity speakers and AVR power.

 

JSS

5 people like this

Share this post


Link to post
Share on other sites

Well thank JSS...Now I don't have anything to post. LOL. <_<

 

But seriously I think point #1 from the above quote is key. Have you heard punchy bass? What was your reference experience for it?

Move to #2 point. Think about that environment, system and playback level. Is your source material, listening space, equipment anything like the reference experience? Is it capable of clean headroom in the neighborhood of what you originally heard? Are you listening to a cd mix with the bass run flat and expecting it to sound like ACDC live from row 10?

 

SME makes a lot of great points as well, but I think the very first step is the evaluation above.

 

As far as identifying a threshold that probably varies greatly for each individual, with frequency, duration and the environment. I just don't see this being quantified any more than in the most general sense. There are just too many variables.

 

Speaking of massive bass attack...I've been listening to a pair of sealed opposed IPAL 21's in my Jeep GC for a few months now. I got bored with my Alpine SWR 10 in the JL stealth box. I'm running them mixed about as hot as I can stand it before the bass becomes annoyingly overpowered compared to the rest of the FR. I only have a single Alpine PDX1000 amp on them which they completely laugh at(1kW to share) and there's barely 6cu ft of airspace for both drivers to share. Damn it is fun though. Monstrous kick drum attack and none of the flubbery bloated linger from a typical peaky 35Hz vented cab. Yep...It's just plain fun.

4 people like this

Share this post


Link to post
Share on other sites

"Are you listening to a cd mix with the bass run flat and expecting it to sound like ACDC live from row 10?"

 

Yes. Duh!

 

"Speaking of massive bass attack...I've been listening to a pair of sealed opposed IPAL 21's in my Jeep GC for a few months now."

 

2142317272.jpg

1 person likes this

Share this post


Link to post
Share on other sites

"Are you listening to a cd mix with the bass run flat and expecting it to sound like ACDC live from row 10?"

 

Yes. Duh!

 

"Speaking of massive bass attack...I've been listening to a pair of sealed opposed IPAL 21's in my Jeep GC for a few months now."

 

2142317272.jpg

He's had Othorns in a vehicle before, so I'm not surprised.

Share this post


Link to post
Share on other sites

Good lord.

 

That's awesome. I always wondered why I don't see more of that kind of thing for bass competition.

Share this post


Link to post
Share on other sites

It's the combination of many frequencies that results in maximum tactile expression.

 

This is a very good example of recorded sound that "feels" as extreme as it "sounds":

 

6PlZHVp.png

 

Take any one of the frequencies that comprise the effect and play it as loud as you like, it won't have the tactile feel of the whole effect. This is what makes great sound design. For example, a similar spread of frequencies with the emphasis shifted downward in frequency gives a completely different tactile effect.

 

They both have fairly equal 40-80 content but present to a human body (and, as Max points out, to your house and furnishings) very differently:

 

GLdhDPz.png

Share this post


Link to post
Share on other sites

He's had Othorns in a vehicle before, so I'm not surprised.

 

Not exactly...What happened is I've had a JL stealthbox for years. Realized I am always toting around some bass cab or another. Alpine amp is under the seat. Thought it would be fun to hook them up while they are in the vehicle. Cut a hole in the fiberglass and threw a 4 pole speakon jack in there. Took a 4 pole speakon and wired it up as a jumper so if it is plugged in the 10" is on as normal. Unplug the jumper and pull the speakon cable out of the spare tire well and plug in whatever cab I'm moving and that's it. Adjust the bass level from the HU.  I did briefly hook up one Othorn in there for a day. Even with only the 1kw amp it was stupid. Not like it was a "real" setup with it or I had it in there for long or anything. Nothing scientific about it, just for giggles.

1 person likes this

Share this post


Link to post
Share on other sites

"The air in the lung cavity may have resonant frequencies based on the size of that individual's lungs which can make them more sensitive to vibrations at a certain frequencies. Body fat will also play a role, as fat will damp resonances. Sobriety level may also play a role."

 

That's very interestin! I'd like to deepen the discussion. Maybe there are some studies (books or pdf) wich i can learn more.. For example about sound intensity and the relationship between PVL and SPL.

 

The isn't a massive body of research in the area of physical sensation of sounds. However a place to start would be to look at the reference section of that Audioholics article I linked to. 

1 person likes this

Share this post


Link to post
Share on other sites

Tactile sensation definitely begins below 116 dB regardless of weighting method. I think the rough threshold may be closer to 90 dB, depending on the content and such. Of course, it depends a lot on the signal and may also depend a lot on the response of the system at the listening position. Another complication is that vibrations in your furniture, either picked up from the floor or resonating with the air, may be transmitted directly to the body. This phenomenon most certainly contributes tactile sensations at lower frequencies than one would probably otherwise feel.

 

It is my own experience that bass at and below 40 Hz is felt by the whole body. Above 40 Hz, the tactile feelings seem to originate from within the torso. The higher the frequency, the higher in the torso they are felt. From 40-60 Hz or so, the feeling may be mostly in the abdomen. From 60-120 Hz, the feelings are localized more in the sternum, and for 120 Hz up somewhere north of 200 Hz, the feelings are felt higher up in chest. Of course, other people may have different impressions, and I'd also bet that women on average experience sensations at somewhat higher frequencies than men.

 

It is also my experience that I notice tactile sensations more readily with transient sounds than continuous sounds. That may simply be due to transient sounds typically being at higher SPL (albeit briefly) than continuous sounds in actual content, but it may also be the case that the body resonances are low Q and are excited more readily by broadband sounds. To the extent that this is the case, it may explain (at least partly) why home theater systems often lack in the "chest punch" area. Systems in residential sized rooms tend to have the most inconsistent response in the 50-200 Hz region because of room resonances and SBIR effects. For anyone who listens with speakers placed ~1-6 feet away from the front wall without sufficient acoustic treatment to absorb the frequencies that are affected by this reflection, there is likely to be one or more deep nulls in the direct part of the impulse response within this crucial frequency range. This tends to spread transients out in time and may considerably reduce the impact felt from them. It has been my own experience as I've made incremental improvements over time that the smoother my response over that range, the better my system punches.

 

I'm not aware of any formal studies linking sound intensity or PVL to tactile sensation, but a few people here have proposed this hypothesis. I personally am skeptical that PVL or sound intensity explains this at all. The human body is not porous, so no air actually passes through it into the chest cavity. Energy is transferred when a difference in pressure between the outside and inside of the chest induces a force, and the force causes acceleration (a change in velocity over time) of the flesh. Impedance is a measure of how pressure it takes to achieve a given PVL in a material. Being dense and solid, flesh has a much higher impedance than air does, and this limits the transfer of energy from the air into the flesh. For more efficient energy transfer, and as a consequence more tactile feel, the impedance of the air should match more closely to the impedance of the flesh. In other words, for more energy transfer, the ratio of PVL / pressure for the air should be *decreased* (i.e., higher impedance in the air) as tends to happen when one is sitting near a wall or some other rigid boundary. But this scenario is opposite to what is being argued by PVL proponents as being important for good tactile feel. My guess is that near-field subs improve tactile response, not because of PVL, but because they interact with the room less and help fill in gaps in the frequency response. Even if crossed at 80 Hz, subs may still contribute a lot of sound, relative to the mains, in the 80-200 Hz region, either because the mains have weak output in that region or because of deep room and/or SBIR nulls.

 

One more point that may or may not be relevant is inductance in the subs and/or mains. Inductance in a woofer reduces high frequency output, increases distortion, and also contributes some phase shift. Some people argue that subwoofer and/or mains with lower inductance have better punch, but I'm not entirely sure how important this is relative to smooth frequency response or if it's important at all. I've definitely noticed more and better punch since upgrading my mains to AE TD12Ms with extraordinarily low inductance. However, these woofers also have a lot more headroom than the woofers they replaced, and the interface between my new speakers and the front wall is *much* better as far as avoiding SBIR effects. Indeed, the increased punch may simply be due to a big improvements in smoothness across the 100-300 Hz range.

That's a very good and complete explanation, thanks SME!

 

You said that when impedance get higher, for example close to a rigid surface, PVL must decrease. Doesn't human body behave like a boundary? Then if we want to maximise the energy tranfered, do we need to take both impedances closest as possible? How can it be done? Maybe increasing air density (for example air humidity and temperature can be a factor). I think the goal is the better impedance matching. A trick can be maximising the radiation surface area of the woofer instead of excursion. Then the resistance seens by the membrane gets higher.

Share this post


Link to post
Share on other sites

It is also my experience that I notice tactile sensations more readily with transient sounds than continuous sounds.  That may simply be due to transient sounds typically being at higher SPL (albeit briefly) than continuous sounds in actual content, but it may also be the case that the body resonances are low Q and are excited more readily by broadband sounds. 

Another factor to consider regarding the greater sensitivity to transient sounds is that there is two class of mechanoreceptor nerves ('touch' nerves that sense vibration and pressure); one which fire only when a change is detected in in the physical state and one which fire when in a certain state. So when these nerves are triggered by pressure, they will both fire at the onset of that pressure, but only one will fire as long as that pressure is continuous. So you could feel more in the attack of a sound than a continuous sound since more nerve activity is registered by your brain at the start of that sensation.

1 person likes this

Share this post


Link to post
Share on other sites

 A trick can be maximising the radiation surface area of the woofer instead of excursion.

 

This may very well be why basshorns are often said to have more slam and punch, with such a huge radiating mouth area.  But it could also be the huge SPL they are capable of producing.

 

JSS

Share this post


Link to post
Share on other sites

That's a very good and complete explanation, thanks SME!

 

You said that when impedance get higher, for example close to a rigid surface, PVL must decrease. Doesn't human body behave like a boundary? Then if we want to maximise the energy tranfered, do we need to take both impedances closest as possible? How can it be done? Maybe increasing air density (for example air humidity and temperature can be a factor). I think the goal is the better impedance matching. A trick can be maximising the radiation surface area of the woofer instead of excursion. Then the resistance seens by the membrane gets higher.

 

I don't believe the human body acts like a boundary, actually.  It's too small in width and depth relative to the wavelengths involved to really cause much reflection.  Instead, the sound mostly diffracts around the body with some of it being absorbed by the body.  The wavelength of 200 Hz is 68", and the wavelength at 100 Hz is twice that at 146".

 

I also don't believe more woofer radiation surface versus excursion makes any difference either.  The reasoning is the same.  What happens instead when the woofer size approaches the wavelength is that the woofer beams.

Share this post


Link to post
Share on other sites

Another factor to consider regarding the greater sensitivity to transient sounds is that there is two class of mechanoreceptor nerves ('touch' nerves that sense vibration and pressure); one which fire only when a change is detected in in the physical state and one which fire when in a certain state. So when these nerves are triggered by pressure, they will both fire at the onset of that pressure, but only one will fire as long as that pressure is continuous. So you could feel more in the attack of a sound than a continuous sound since more nerve activity is registered by your brain at the start of that sensation.

 

Do you have a reference for this?  It agrees strongly with my subjective experience.  In fact, one thing I really noticed when I got bass traps is just how much less I *heard* bass transients and how much more I *felt* them instead.  This makes me wonder if we are more sensitive to impulsive than continuous vibrations in general.  That would be fascinating because that's totally opposite of how the ear works.  Anyway, I've had a hard time finding good literature on vibrotactile sensation using Google.  That's a real shame, because I'd like to know more.  Undoubtedly, vibrotactile sensation has abig impact on the overall listening experience, even though we don't have any kind of reference to calibrate ourselves to.

Share this post


Link to post
Share on other sites
#1...Identify your reference. What exactly was the time/place/system that you so desperately want to recreate? For me and for so many others it is often a concert or many concerts or live events with huge stacks of very efficient speakers. For another smaller amount of people it may be a car audio system. Again probably multiple big sub drivers, lots of power and a very efficient space. Does anyone else's reference for a punchy bass system come from anywhere else? Mine is from both.

 

I don't have any real car experience, but I have felt some nice kick at live events.  I've also heard some live system with a heck of a lot of SPL but not much punch at all.  Yes, it might be enough to feel a lot in my chest, but it does not have that feeling of swift impact, if you know what I mean.

 

My current reference then may be some of the Danley recordings, which I listened to after getting my new mains speakers setup with the Motu.  For anyone unfamiliar with these, the dynamics in these recordings will blow up your stuff if you don't know your system's limits, so be careful and start low.  In one of the parade recordings here, there a drum troupe that walks by playing drums (not sure of the type) that have a very with some very tonal resonances resonant pretty strongly in the 100-200ish range range that just pummel my chest.  It's not an isolated resonance either because the drums are tuned to different frequencies.  Other drummers (in the same troupe, IIRC) beat their sticks on drum parts and create very strong treble transients.  I actually backed down the volume briefly when I saw how high the peak levels to the horns (active crossover here) were bouncing on my Motu front display.  While these didn't quite slam, they did exhibit a kind of realism you don't really hear in most recorded material.  Anyway, the fireworks are the real king of slam.  They made the peak-hold bars on my Motu jump higher than anything else.  And oh, did they slam!  I've never experienced anything like it from an audio system.

 

So yeah, I totally agree with you that SPL matters a lot!  The cool thing is that you can get excellent slam from high SPL transients without irritating the ears, as long as you can find source material that has the dynamics.  Too bad a lot of music content has pretty weak bass these days.  It's just another casualty of the loudness war where bass gets shoved aside to make room for loud upper mids and treble.  But that is far from universal.  You may have to look around, but you can find lots of examples of well recorded music with good dynamic range.  There's little gems hidden everywhere.  Take YouTube for example:

 

This Marc Broussard guy can sing, wow!  But seriously, I absolutely love the sound on this video and still need to figure out if they actually have a BD or not.

 

 

I understand this Metallica movie is a GTG favorite.  The double kick drum is a phenomenal tactile assault in my experience:

 

 

These tracks are great played at levels approaching and even exceeding theatrical reference.

 

I also have a "Shpongle - Live at Red Rocks" BD with fantastic sound.  While some members of the band appeared to not be having the best night, the recording, mixing, and mastering on that BD are absolutely stunning.  I'm quite familiar with the Red Rocks venue (outside Denver, CO), and I've never heard anything that captured its acoustics so well.  But it was actually better than that.  I got to hear and feel the super, tight chest thumpy bass that I'd expect to hear sitting near the front of the house and at the same time, hear the ambiance of the outdoor acoustic space as it would sound in the mid-field (roughly half way back) at the same time.  And of course, all that enjoyed without the wind causing phase distortion and less-than-stellar line arrays.

 

Other than that, I've got a fair number of digital downloads and CDs with DR and plenty of slam.  Lots of stuff from the mid to late 80s is very nice and open.  And invariably, the ones that aren't as loudness-warred have much nicer tactile bass.  Some Jazz releases also have some great DR, and you can get drum hits that slam pretty nicely.

 

So yeah, content is a big deal.  I've been to a few weddings (both of my sisters', actually) in which I felt plenty of bass in my chest, and I left the room both times within minutes because the average SPL was so abrasive and the systems were distorting so badly.  You can try to EQ more bass out of that kind of stuff, but most likely, all you'll get is a muddier, more bloated sound.  I hope the loudness war winds down quickly with level normalization becoming more commonplace.

 

One last thing.  I think the 80-200 Hz range (and maybe higher) is underrated for tactile sensation.  In fact, it might be more important than 40-80 Hz.  On a few occasions, I've tried cranking up the sub level, just to hear what "too much bass" sound like.  The thing is, I don't like it at all.  The sub bass bloats way too much and drowns out all the higher stuff that gives it definition and speed.  My experience is that it actually *loses* punchiness.  A more satisfactory solution is to EQ in a gentle house curve that raises the levels well above the typical sub crossover.  Mine starts at 200-300 Hz and is 2 or 3 dB higher by the time it hits 80 Hz.  Yeah, tends to place greater demands on the mains.  Newsflash to resident bassophiles here: don't skimp on the mains.  :)  High headroom and clean response in the higher octaves makes a huge impact on the "bass" as your hear it.  Harmonics are a crucial part of any bass sound, *especially* in so far as the perception of speed is concerned.

1 person likes this

Share this post


Link to post
Share on other sites

High headroom and clean response in the higher octaves makes a huge impact on the "bass" as your hear it.  Harmonics are a crucial part of any bass sound, *especially* in so far as the perception of speed is concerned.

 

That's simply right! For example when you mix a kick drum, it's a common mistake to emphasize just around 60-80 hz to get more punch, because in this way you just reduce the attack of the kick. You have to get a flat frequency response, leaving the kick's energy to pass equally around the band. Try to loops the kick in the mix with main speakers and subwoofers on.  After turn off main speakers, only allowing the kick' fundamental to pass through subwoofer. You will notice a lack in the punch. That's an extreme example but it gets the idea.

 

I also don't believe more woofer radiation surface versus excursion makes any difference either.  The reasoning is the same.  What happens instead when the woofer size approaches the wavelength is that the woofer beams.

 

Yes, beams and directivity are another fact... But if we take two selaed enclosure for the same pressure generated i think that the smaller one needs to move faster than big one. So the smaller one produces more PVL in the near field. Ported subs are another story, we need to take into account the port velocity. At high level, undersized ports act like a damper, so the high velocity will compress the air too much resoulting in lacking of SPL 

 

Anyway i also think that air's temperature, humidity and viscosity play an important role in how we perceive sound intensity. That's can be a reason why there are some days who i feel more tactile feedback from my system at the same loudness.

 

p.s sorry for my quite bad english, i come from italy  :)

Share this post


Link to post
Share on other sites

I will quote Ricci on the subject as well:

 

"Midbass...or bass punch or whatever...In my opinion it goes like this.

 

#1...Identify your reference. What exactly was the time/place/system that you so desperately want to recreate? For me and for so many others it is often a concert or many concerts or live events with huge stacks of very efficient speakers. For another smaller amount of people it may be a car audio system. Again probably multiple big sub drivers, lots of power and a very efficient space. Does anyone else's reference for a punchy bass system come from anywhere else? Mine is from both.

 

 

I recently had the opportunity to listen to a friend's car audio system. Two 15" ported subs with 4x8" mids and then a lot of power.. All wich can i say is that the pressure was very crazy, i don't know that spl but i supposed to be over 130 db at the lower octaves. Sure cabin gain was extreme, but i didnt really feel the impact like standing 30-40 feet from a small-medium live concert rig. Of course the played back music from the car was less dynamic (7-10 db crest factor max) as well all the most recent products. Anyway the pressure in that sealed car made me feel my ears like being underwater, but not slam at all. That made me think the pressure is not what i looking for.

 

I think the key is to know how different sound field properties behave:

 

1) car sound field: LP approach near field, then wave front behave like spherical wave, so PVL and SPL are out of phase

 

2) concert sound field: LP approach far field, then wave front behave like plane wave, so PVL and SPL are in phase.

 

That's may be a reason and i firmly believe that SIL plays a very important role in how we perceive the intensity through our body

Share this post


Link to post
Share on other sites

p.s sorry for my quite bad english, i come from italy  :)

Nonsense, you write quite well and I hope you continue to post. Thanks for sharing your experience.

Share this post


Link to post
Share on other sites

Do you have a reference for this?  It agrees strongly with my subjective experience.  In fact, one thing I really noticed when I got bass traps is just how much less I *heard* bass transients and how much more I *felt* them instead.  This makes me wonder if we are more sensitive to impulsive than continuous vibrations in general.  That would be fascinating because that's totally opposite of how the ear works.  Anyway, I've had a hard time finding good literature on vibrotactile sensation using Google.  That's a real shame, because I'd like to know more.  Undoubtedly, vibrotactile sensation has abig impact on the overall listening experience, even though we don't have any kind of reference to calibrate ourselves to.

There is a huge wealth of information about vibrotactile sensation out there, you must have been using the wrong search strings. If you want to know about the different mechanoreceptors, a great place to start (as always) is wikipedia: mechanoreceptors. The types we are interested in for this discussion is cutaneous RA and SA mechanoreceptors (rapidly adapting and slowly adapting). Rapidly adapting are the receptors that only sense change of state, but does not say what the state has changed to. Slowly adapting senses the state of the nerve, but, as their name implies, does not react swiftly by comparison. Here are a few interesting youtube videos that make this subject accessible and explains the jargon a bit:overview of sensation 1, 2, 3. There is a ton more about this out there, but that is a great intro. 

Share this post


Link to post
Share on other sites

...

That made me think the pressure is not what i looking for.

 

I think the key is to know how different sound field properties behave:

 

1) car sound field: LP approach near field, then wave front behave like spherical wave, so PVL and SPL are out of phase

 

2) concert sound field: LP approach far field, then wave front behave like plane wave, so PVL and SPL are in phase.

 

That's may be a reason and i firmly believe that SIL plays a very important role in how we perceive the intensity through our body

 

This is a major problem when trying to reproduce realistic low frequency sound inside any small space - you easily get very high spl, but the sound intensity is very low if the space is acoustically sealed.

 

This is mainly a problem at very low and low frequencies, below 40-60hz.

Higher up there are 2 factors that change things - one is perception of sound is different, and dimensions of the space becomes large compared to wavelength. 

Share this post


Link to post
Share on other sites

One last thing.  I think the 80-200 Hz range (and maybe higher) is underrated for tactile sensation.  In fact, it might be more important than 40-80 Hz.  On a few occasions, I've tried cranking up the sub level, just to hear what "too much bass" sound like.  The thing is, I don't like it at all.  The sub bass bloats way too much and drowns out all the higher stuff that gives it definition and speed.  My experience is that it actually *loses* punchiness.  A more satisfactory solution is to EQ in a gentle house curve that raises the levels well above the typical sub crossover.  Mine starts at 200-300 Hz and is 2 or 3 dB higher by the time it hits 80 Hz.  Yeah, tends to place greater demands on the mains.  Newsflash to resident bassophiles here: don't skimp on the mains.  :)  High headroom and clean response in the higher octaves makes a huge impact on the "bass" as your hear it.  Harmonics are a crucial part of any bass sound, *especially* in so far as the perception of speed is concerned

 

 

I actually did a sort of half-ass 'experiment' with this.  I ran a known soundtrack with 'slam' with my system at near Ref, with and without Etymotics in my ears:

 

etyplugs_nr_chart_foam_2015b.png

 

Taking out the high frequencies definitively took away impact, much more so than I would have expected.  The cochlear mechanism has a significant say in how much impact a sound has on our body.  You need VERY capable mains as well as a capable sub system and terrific room acoustic treatment to do the Danley recordings justice.

 

Thanks for the link!

 

JSS

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0