[bigshot]

Dispersion is a big issue for sure. Tweeters are highly directional and there are all kinds of tricks speaker manufacturers use to increase the sweet spot. My mains are custom made 15 inch 5 ways made by a designer at JBL back in the late 70s. They have the JBL "bullet" super tweeters, which is basically the JBL slot tweeter with a chrome plated "Studebaker nose" horn on it. It's not quite as directional as a standard tweeter, but that's OK because I have a center speaker to bridge the gap. My rears are KEF with concentric nested drivers that are designed to produce a super wide dispersion pattern by putting the source of all the frequencies in the exact same spot. The sound radiates out broader that way without crossover issues. My theater is about 20 feet across, and the rear channel is able to create a solid phantom center, even with that wide gap between speakers. There are also horn loaded speakers that emit a stripe of sound. I used to have a pair of horn loaded super tweeters and they worked like gangbusters.

 

[Davesrose]

Dispersion is a big issue for sure. Tweeters are highly directional and there are all kinds of tricks speaker manufacturers use to increase the sweet spot. My mains are custom made 15 inch 5 ways made by a designer at JBL back in the late 70s. They have the JBL "bullet" super tweeters, which is basically the JBL slot tweeter with a chrome plated "Studebaker nose" horn on it. It's not quite as directional as a standard tweeter, but that's OK because I have a center speaker to bridge the gap. My rears are KEF with concentric nested drivers that are designed to produce a super wide dispersion pattern by putting the source of all the frequencies in the exact same spot. The sound radiates out broader that way without crossover issues. My theater is about 20 feet across, and the rear channel is able to create a solid phantom center, even with that wide gap between speakers. There are also horn loaded speakers that emit a stripe of sound. I used to have a pair of horn loaded super tweeters and they worked like gangbusters.

Interesting....not familiar with JBL supertweeters of the 70s. Trying to google, are they a metallic cone design? That would be very different than today's offerings. Very unique. My speaker system is very good for Atmos surround at calibrated listening positions in my room. The tweeters have a higher dispersion being silk domes (compared to say ribbons)...so they do have a good sound stage if I'm just listening in stereo mode. The mid woofers are made of Kevlar. What's also unique about my center and main tower speakers is that they have a metal grills instead of cloth ones (which my matched bipole surround speakers have cloth). The metal may cut down a bit on some mid frequencies (and it is the ultimate child guard too with loudspeakers). With the latest surround systems, your crossover settings with the receiver is also important (IE how much bass is being directed for each channel as subwoofer LFE).

 

[gregorio]

what you guys say about people saying that supertweeters (20khz-40khz) enhance their music expierence?

Delusional. There’s nothing but audiophile marketing (and those deluded by it) to support such claims but there’s a wealth of scientific evidence to counter it, dating back to the late 1890’s.

Basically the research shows that some humans can hear above 20kHz but with ALL the following conditions: They have to be no older than their early 20s. Only a small percentage of people in this age group can hear above 20kHz. It has to be pure tones, not music or noise which includes >20kHz tones. The pure tones have to be very loud, typically around 110dB or higher. Tones up to around 24kHz have been detected by a very few subjects but at even higher levels, 115-120dB. Typically only with the use of in ear or on ear custom devices, not speakers or typically consumer HPs or IEMs, which cannot handle such HF high SPLs without distortion. More recent studies in the last few years (this one for example) demonstrate that the auditory cortex of the brain shows no activity/response above the individual thresholds. Although there’s been quite a few studies over the last 40 years or so, there’s not a huge amount due to the danger of causing hearing damage, even at short exposure durations.

which might be not audible directly, but either ultrasonic soundwaves mess with audible frequencys or we can "detect" them in a other way... skin?

Nope, to be audible, the modulation of audible freqs has to be with other audible freqs. This is an easy test, see if you can hear the difference between a sine wave and a square wave at say 12kHz. We can in fact sense ultrasound up to about 100kHz but through bone conduction and again, very high SPLs. So again, not applicable to listening to music on your hi-fi, unless you bolt your super-tweeter to your skull and max out the volume!

mp3 or CD quality (16bit ,44,1khz) surpresses those frequencys, so i truely believe lossy isnt "all humans need"

Actually, the opposite. Firstly, those subjects who could hear ultrasonic freqs at high SPLs almost unanimously described the experience as uncomfortable or unpleasant, not one subject liked/enjoyed it. Secondly, the higher the frequency content (and the higher the SPLs) the higher the chance of your amp or drivers producing audible Inter-Modulation Distortion, and it’s almost guaranteed at the SPLs and freqs mentioned above. So removing >20kHz content is beneficial.

G

 

[Ghoostknight]

Basically the research shows that some humans can hear above 20kHz but with ALL the following conditions: They have to be no older than their early 20s. Only a small percentage of people in this age group can hear above 20kHz. It has to be pure tones, not music or noise which includes >20kHz tones. The pure tones have to be very loud, typically around 110dB or higher. Tones up to around 24kHz have been detected by a very few subjects but at even higher levels, 115-120dB. Typically only with the use of in ear or on ear custom devices, not speakers or typically consumer HPs or IEMs, which cannot handle such HF high SPLs without distortion. More recent studies in the last few years (this one for example) demonstrate that the auditory cortex of the brain shows no activity/response above the individual thresholds. Although there’s been quite a few studies over the last 40 years or so, there’s not a huge amount due to the danger of causing hearing damage, even at short exposure durations.

im not talking about "hearing" the ultrasonics itself

We can in fact sense ultrasound up to about 100kHz but through bone conduction and again, very high SPLs. So again, not applicable to listening to music on your hi-fi, unless you bolt your super-tweeter to your skull and max out the volume!

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, the opposite. Firstly, those subjects who could hear ultrasonic freqs at high SPLs almost unanimously described the experience as uncomfortable or unpleasant, not one subject liked/enjoyed it.

well this doesnt surprise me at all if it was tested with 120db lol
i also think in general pure sinewaves above 12khz have something unpleasent to them


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, and if thats the case supertweeter may be even more "effective" in producing a difference

 

[Davesrose]

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, and if thats the case supertweeter may be even more "effective" in producing a difference

Lets just assume that "typical" human hearing can go above 20kHz. What does that add? All the fundamentals with musical instruments and sound reproduction do not reach 20kHz. I have heard an argument that going above this with the sound format is important for sound stage or reflections....but this is impossible. There are always going to be inherent differences in acoustics/reflections with a live performance vs a reproduced one (and the audio engineer doing the mixing is focused on how the reproduced musical performance sounds).

 

[Ghoostknight]

Lets just assume that "typical" human hearing can go above 20kHz. What does that add? All the fundamentals with musical instruments and sound reproduction do not reach 20kHz.

"electronic stuff", distortion, hamonics, hi hats all "can" go way up there and may alter the expierence, no?
this might be not a huge deal with instrumental music but overall i think it is with different genres

 

[Davesrose]

"electronic stuff", distortion, hamonics all "can" go way up there and may alter the expierence, no?
this might be not a huge deal with instrumental music but overall i think it is with different genres

I can't see how it can. So there are harmonics that go above fundamental notes....yet they become irrelevant as that's about the reflections of the actual performance. Trying to replicate "live" music could be the hardest task (as gregorio could say, as he's an audio engineer)....as it requires more attention with microphone placement, acoustic treatments, and how you mix. Other modern genres I would think are easier: a lot of synthesized stuff has a focus on emphasized bass.

 

[bigshot]

Interesting....not familiar with JBL supertweeters of the 70s. Trying to google, are they a metallic cone design?

Here is an eBay auction for a pair. (The price they want is insane.)
https://www.ebay.com/itm/195632672712

 

[Ghoostknight]

yet they become irrelevant as that's about the reflections of the actual performance.

why is that so?
well my room has good absorption i would say, bass traps in corners, heavy furniture on nearly all walls, rug on the floor, one on the wall behind the speakers, one on the ceiling
and imo creating such a "studio space" is the optimal way since you hear with flat speakers "exactly" or close to it what the sound engineer heared, even if some tune their music to crappy/heavly reflecting systems..

my point saying this is, if your room is treated like that your listening room "vanishes" in the music, you actually hear the recording and NOT your own room, specially if its a nearfield setup too

this can probably give you the best "live" expierence imo and in this case high frequency response is actually kinda important, since you need it to replicate the "reflections" of the recording instead of your room doing some of the work

 

[bigshot]

"electronic stuff", distortion, hamonics, hi hats all "can" go way up there and may alter the expierence, no?

Even if you could hear it (you can't) it would be masked by lower louder frequencies in the audible range.

 

[Ghoostknight]

Even if you could hear it (you can't) it would be masked by lower louder frequencies in the audible range.

yea thats what studys suggest,
1. on unknown systems
2. with random peoples
3. in a random listening room setup
4. that probably listen to mp3/crappy headphones usually..

so im always not sure if i should take random studys seriously, instead i see what actually makes a difference in my setup
i said it before and i say it again, alone the fact that people try to suggest absolute phase doesnt matter is a huge red flag for me, there are dozens of songs that make use of it (and you wanna listen to it the right way around )

 

[Davesrose]

why is that so?

Because the live performance has its own reflections that are always going to be different than your listening environment. The complete science can be complicated about "phase distortion" (and there's other threads here that go into that)....but suffice it to say it's something that's always present and different with a live performance (and why an audio engineer does not account for it: they are looking for the best "direct" sound of each instrument).

well my room has good absorption i would say, bass traps in corners, heavy furniture on nearly all walls, rug on the floor, one on the wall behind the speakers, one on the ceiling
and imo creating such a "studio space" is the optimal way since you hear with flat speakers "exactly" or close to it what the sound engineer heared, even if some tune their music to crappy/heavly reflecting systems..

So that means you enjoy your sound system, and it meets the "approximate" intent of what the audio engineer's intent was with the album's mix.

 

[bigshot]

my point saying this is, if your room is treated like that your listening room "vanishes" in the music, you actually hear the recording and NOT your own room,

That isn't ideal because mixes are designed to use room reflections to fill out the body of the sound and give it life. Flat response isn't enough. Music is engineered with room acoustics with the specific expectation that it will be listened to with room acoustics. Reflections aren't automatically bad. Only bad reflections are bad. Those are the ones that mess with response.

We're very sensitive to delays caused by room reflections, and that is what our brain uses to interpret what "real" sounds like. In real life, sound inhabits its space. It reflects, it reverberates, it comes from different directions and all of that provides an envelope around the sound that makes it sound present to us. Without that, sound may be more detailed, but dead sounding. If you want that kind of sound, closed headphones are better because they put the sound in an acoustic vacuum.

You can't really get this kind of effect with near field speakers. They're kind of like halfway between a full speaker setup and headphones... a little of both worlds. Even though it can be a lot of work to optimize a room for a speaker installation, the rewards are huge. You have physical sound inhabiting a real space. You feel the bass in your chest, the air vibrates around you, and the music inhabits the same room you're sitting in and interacts with it. This is something that isn't widely understood in Head-Fi because this is populated mostly by headphone listeners.

 

[bigshot]

yea thats what studys suggest,
1. on unknown systems
2. with random peoples
3. in a random listening room setup
4. that probably listen to mp3/crappy headphones usually..

You should do some googling on auditory masking. Take a cymbal hit for instance. The fundamentals in the audible range are huge. But as you go up higher through the first, second and third harmonics, the energy varies and diminishes. Louder sound an octave below will mask a frequency. So add lower energy in the harmonics and louder lower frequencies creating masking, and you end up with something you can't hear. Sound engineers usually worry about three levels of harmonics. Beyond that there is no point worrying about it because you can't hear it. The vast majority of instruments have three levels of harmonics in the audible range. The ones that have higher harmonics are usually masked. The exception to that would be Gamelan gongs, but I'm probably the only person around here who has CDs of that.

 

[Davesrose]

Since we are on the topic of frequency range with instruments....there's also esoteric needs for having fundamental notes in the lower bass region. So I have a few great organ performances that do get into the lowest regions of pipe organ music. It's the registers where you don't technically hear, but I feel with my subwoofer. It should also be evident with folks that there are modern music genres that are all about the bass (should I try to resist including the link for Meghan Trainor?).