[bigshot]

If you don't have a powerful subwoofer, I doubt your system goes below 20Hz. It takes a huge amount of power and a great deal of excursion to push those ultra low frequencies. I have a sunfire sub that goes down to around 11Hz. I have to reel it in because it hits the resonant frequency of the walls and the building materials inside the walls start buzzing and rattling. That's only with movies though, not music. Movies go as low as a system can handle. Popular music resides above 40. Classical music above 80.

When I was a kid, I was all into bright treble and heavy bass. Classic U shaped curve. As I listened more, I realized the limitations to that. It isn't very clear sounding that way. The octaves at the farthest reaches of the audible spectrum really aren't that important for music. Most transducers make a hash of them if they reproduce them at all. The most important frequencies to balance are the ones in the middle, particularly the area of sensitivity above 2kHz. If you can get flat from 10kHz to 80Hz, you're doing very good. Anything below 80 is a bonus- not vital, but nice to have.

 

[gregorio]

well im not sure how they tested but if not playing music at the same time the result could vary a lot i guess

Actually there’s been quite a lot of research into bone-conduction audibility because there are quite a few potential applications, hearing-aids being just one. Testing of bone-conduction is less potentially damaging because you can just mechanically create the vibrations coupled to the skull, rather than actually blasting the ears with high SPLs. Think of the old trick of placing a tuning fork against the bone behind the ear.

well im not sure where it comes down to but i can use a lowpass filter starting(!) at 16khz and still hear a difference, even if my hearing just goes to 15-15,5khz
right now i can just explain it that the high frequencys "modulate" other frequencys to some degree which leads to a audible difference

Ah, unfortunately that’s a common audiophile issue! They only know, are only “sold” or can only think of one explanation, so they jump on it. In reality, there are various other potential explanations, all of which are almost infinitely more likely because they all commonly occur and are all provably audible, while hearing differences caused by modulating with freqs above the hearing threshold has never been shown to be audible. Again, this is very easy to test yourself, a square wave sounds the same as a sine wave at say 12kHz because the difference is the square wave has (inaudible) harmonics. Likely explanations are: Using a LPF at 16kHz acts as a reconstruction filter and raises the output level typically by 0.5-3dB, so that’s within audible thresholds. Depending on the filter design, it will cause phase variations lower in the spectrum (group delay for example), again audible. Filtering out >16kHz could easily be removing HF causing IMD far lower in the spectrum, which is audible even at very low levels because it’s dissonant (unrelated harmonically).

G

 

[Ghoostknight]

Using a LPF at 16kHz acts as a reconstruction filter and raises the output level typically by 0.5-3dB, so that’s within audible thresholds

with Q of 0.7 ?

Depending on the filter design, it will cause phase variations lower in the spectrum (group delay for example), again audible.

EasyEffects offers not just IIR filters, but also FIR and SPM which shouldnt mess with phase

Filtering out >16kHz could easily be removing HF causing IMD far lower in the spectrum, which is audible even at very low levels because it’s dissonant (unrelated harmonically).

how?

Again, this is very easy to test yourself, a square wave sounds the same as a sine wave at say 12kHz because the difference is the square wave has (inaudible) harmonics.

will try later

 

[Steve999]

We’ve covered some of this ground before. Low E on a typical electric bass or a jazz stand up bass or classical string contrabass / double bass (same thing as a stand up bass really just played differently) goes down to 41 hz. So the fundamental in lot of modern music down to 41 hz gets a lot of play, though sometimes our brain just infers it if the recording or a speaker system doesn’t recreate it to the extent it was present when performed, a phenomenon that is called the missing fundamental.

So 41 to 80 hz in most music we listen to is way more than a rumble. Still, I don’t see too much reason to doubt, I wouldn’t be surprised if it’s true, that most of the bass present is between 80 and 120 hz. I’m just saying there’s lots of musically meaningful stuff, including tuned pitch, from 41 hz on up. And on many systems, even more so without subwoofers, 40 to 80 hz is not covered well or evenly due to limitations in speakers and recordings, and due to room modes. When it is recorded and reproduced well it feels pretty cool.

I’ve also seen it demonstrated to a classroom full of music majors that a lot of people lose the ability to discern pitch well somewhere between 41 and 80 hz, and I imagine this would be even more so if they didn’t play instruments, but that’s a different kettle of fish.

 

[bigshot]

A bass covers three octaves, doesn't it? That would be around 40 to 320Hz. I would imagine most of the playing would be somewhere in the middle around 80-160Hz. I guess it depends on whether the player is one of the bass players who doesn't play a lot of melody and just treats the bass line percussively, or whether they're the kind that plays low tunes under the leads.

 

[danadam]

if you have "infrasonic" music give some examples to test

Maybe: Michael Murray - The Organ at St. Andreas-Kirche, Hildesheim

 

[Davesrose]

If you don't have a powerful subwoofer, I doubt your system goes below 20Hz. It takes a huge amount of power and a great deal of excursion to push those ultra low frequencies. I have a sunfire sub that goes down to around 11Hz. I have to reel it in because it hits the resonant frequency of the walls and the building materials inside the walls start buzzing and rattling. That's only with movies though, not music. Movies go as low as a system can handle. Popular music resides above 40. Classical music above 80.

Most music has all content that's above 80Hz: there are some exceptions (IE certain pipe organ music or particular synthesized music).

As far as subwoofer, that is the one component I find interesting about my receiver's auto calibration (where it's playing test tones with each speaker and determining position and crossover frequency queues with a microphone). My sub has a pretty powerful amp for it's driver (12" high excursion). The calibration setup asks to lower my subwoofer level quite a bit (IE going past 1/4 is too loud for it). I start with the calibration, but then I also have a laser pointer for dialing in speaker distance and SPL meter to get consistent levels with my primary listening positions. It's interesting the amount of discussion in AV forums about what crossover you should set with speakers and bass settings for the subwoofer. Since my receiver has a pretty good remote app on my phone, I do have the level set a bit higher, and then adjust a negative offset on my phone (where grossly speaking, streaming content might have a lower level than blu-ray).

 

[Davesrose]

Actually there’s been quite a lot of research into bone-conduction audibility because there are quite a few potential applications, hearing-aids being just one. Testing of bone-conduction is less potentially damaging because you can just mechanically create the vibrations coupled to the skull, rather than actually blasting the ears with high SPLs. Think of the old trick of placing a tuning fork against the bone behind the ear.

There's actually now bone conducting headphones as well. They've entered the market for people wanting to listen to music while working out (and don't have to worry about shorting out the driver ).

 

[bigshot]

As far as subwoofer, that is the one component I find interesting about my receiver's auto calibration (where it's playing test tones with each speaker and determining position and crossover frequency queues with a microphone). My sub has a pretty powerful amp for it's driver (12" high excursion). The calibration setup asks to lower my subwoofer level quite a bit (IE going past 1/4 is too loud for it).

My calibration wanted me to turn my sub off altogether! I think some calibration software schemes have their limits.

 

[Davesrose]

My calibration wanted me to turn my sub off altogether! I think some calibration software schemes have their limits.

Indeed....I just used mine as the first baseline before adding my own measured settings. Then there's still so much debate about what kind of crossover to apply for your mains, or surrounds and if you should apply a "cinema EQ" (to attenuate the treble).

 

[bigshot]

After hitting the recommendations of calibration, I go by ear. Calibration in a home system is a direction, not a destination.

 

[Steve999]

Lots of content from 41 to 80 hz in jazz, rock & classical. Every time you see someone play an open E string on the bass (the lowest note on the lowest string) that’s 41 hertz. That note gets a lot of play and that lowest octave guests a whole lot of play, in rock, jazz and classical, acoustic and electronic. Not trying to be argumentative, it’s just a simple day-to-day fact.

Guitar starts an octave up from a bass. The low E on a bass is one octave down from the lowest note on a guitar. Just to help folks visualize it if you haven’t had regular exposure to the different instruments, @Davesrose I know you’ve had lots of experience on guitar, and @bigshot i know you’ve taken a crack at guitar now and then, which puts you in a good place to try to visualize this stuff. That low E on a guitar, that is in the vicinity 82 to 83 hz. Everything that is on a bass that is not on a guitar, that’s 41 hz to 80 hz, and it is ubiquitous in Western music. Honest!

 

[Steve999]

My calibration wanted me to turn my sub off altogether! I think some calibration software schemes have their limits.

You have probably heard of it, I used REW and a UMIK-1 on an Apple laptop, using I think it was sine wave frequency sweeps, and EQ’ed things manually and by trial and error, adjust and measure, adjust and measure, also move the subs around some, until I got smooth bass. With no EQ and my two subs I have crazy emphases due to room modes under 40 hz and between around 100 to 120 hz. I obsessed over it for a couple of weeks and finally decided good enough, I learned a ton in doing so, and the improvement in sound was really gratifying.

 

[Mintz]

Man... this is not the way I thought this thread would go...

 

[bigshot]

Yeah Steve999, I understand what you're saying. You're just pointing at lowest notes. I'm pointing at the middle of the range, assuming that the average notes played are in the middle. Maybe some bass players play all in the bottom octave. I never played a bass. But I like Jaco and Tina Weymouth.