What do you think what's a useful infrasonic extension for home theatre? I loved chasing single digit extension but I'm not so sure anymore.
I had the Bag End Infrasub18 that played 8Hz. It sounded nice although only at very low levels.
I built a dual RCF LF18N405 450L ported subwoofer tuned @15hz in my hobby room. This one still puts a smile on my face when played at higher levels.
The problem is this though:
I built a dual B&C 21SW152-8 540L ported subwoofer tuned @11Hz in my living room and I also have a quad Visaton 15" TIW400 sealed subwoofer in there. I did some measurements and the sealed sub quickly drops off under 30Hz. Both ported subs also have a gap between their tuning frequency and the first room mode and I feel that both subs together fall a bit short around 20Hz without EQ. Also the movies with 10Hz content are rare.
I'm thinking of raising the port tuning of the B&C to 15Hz and also rebuild the sealed sub into a ported one also tuned at 15Hz. This way GD only starts to rise under 20Hz so music still sounds tight? The (still low) tuning frequency will also prevent the woofers from over-excursion below tuning?
Your thoughts?
I had the Bag End Infrasub18 that played 8Hz. It sounded nice although only at very low levels.
I built a dual RCF LF18N405 450L ported subwoofer tuned @15hz in my hobby room. This one still puts a smile on my face when played at higher levels.
The problem is this though:
I built a dual B&C 21SW152-8 540L ported subwoofer tuned @11Hz in my living room and I also have a quad Visaton 15" TIW400 sealed subwoofer in there. I did some measurements and the sealed sub quickly drops off under 30Hz. Both ported subs also have a gap between their tuning frequency and the first room mode and I feel that both subs together fall a bit short around 20Hz without EQ. Also the movies with 10Hz content are rare.
I'm thinking of raising the port tuning of the B&C to 15Hz and also rebuild the sealed sub into a ported one also tuned at 15Hz. This way GD only starts to rise under 20Hz so music still sounds tight? The (still low) tuning frequency will also prevent the woofers from over-excursion below tuning?
Your thoughts?
I have 15" Karlson's home made. My speakers (old repaired Sansui from 70's) go down to about 30Hz in the cabinets. Years ago I enjoyed play lous a pure tone of 20/30 Hz from my PC (AMD486) runing Daqarta and feel that my house moves in all directions. Once my neigbour downside believed it was an earthquake. 
🙄
🙄I am always bemused by these low frequency 'hypothetical' debates. Your audio spectrum is likely 20Hz to 15Khz so you are attempting reproduce frequencies that you cannot 'hear'. Infrasonic vibrations felt, received through the sense of touch as opposed to sound.
Whatever measurements you make are irrelevant because YOU are ultimate recipient.
A 'microphone' to measure human reception of infrasonic vibrations would need to be 1.7m tall have a liquid based body with a volume in excess of 75 litres and contain millions of sensors.
Another issue with infrasonic frequencies concerns the medium of travel from source to receiver - air is not necessarily the predominant route.
Whatever measurements you make are irrelevant because YOU are ultimate recipient.
A 'microphone' to measure human reception of infrasonic vibrations would need to be 1.7m tall have a liquid based body with a volume in excess of 75 litres and contain millions of sensors.
Another issue with infrasonic frequencies concerns the medium of travel from source to receiver - air is not necessarily the predominant route.
Yes I can also make the house move. The doors of the closets upstairs rattle in their hinges at certain levels/frequencies. That's why wouldn't mind having a large cellar with thick concrete walls as a home theatre.I have 15" Karlson's home made. My speakers (old repaired Sansui from 70's) go down to about 30Hz in the cabinets. Years ago I enjoyed play lous a pure tone of 20/30 Hz from my PC (AMD486) runing Daqarta and feel that my house moves in all directions. Once my neigbour downside believed it was an earthquake.
In the old days, the given audible range was 16Hz to 16kHz. It's much more realistic than the 20Hz to 20kHz we've been working off of for awhile now. Simple fact of the matter when hearing range is tested by the people who actually know what they're talking about (ie PhDs whose careers are focused on it and depend on repeatability by others, not audio "experts" whose sum total of support for their position is their egos and "common sense" which is anything but sensible), the audible range extends much further down than it does up. The same people who can't hear squat above 14kHz can still hear tonality at 14Hz if it's of sufficient level to exceed the background noise of the body. If you look at the various Equal Loudness Contour curves that have been published over the years, you'll even see that our hearing is more sensitive to the lower frequencies than higher once that level is exceeded as evidenced by how the Son lines draw closer to one another in the bass frequencies. (That's what those lines are on the graphs, btw. At 1kHz, 1dB equals 1phon, the subjective measure of loudness. 10phons equals 1son. 1son equals a perceived doubling of said subjective loudness of the sound. At 1kHz, the separation between son lines is 10dB, but at 10Hz it's closer to 1dB. So, 1db louder below 10Hz sounds as loud of an increase as 10dB more output at 1kHz. Cool, huh?)
Sigh, you'll find no greater amount of disinformation on hearing than from audiophiles on forums claiming what supposedly isn't audible at the lower frequencies, unfortunately.
Anyways, there is the practical aspect to consider. Halve the frequency, quadruple the needed displacement. Room gain helps there, but usually only enough to offset the natural roll-off in any design you'll be building. As you've probably already experienced, it takes a loooot to get output in the single digits without excessive distortion, an impractical amount unless you're kind of nuts. I'm the latter, yes, but acknowledge practical limits. Probably a good point to call it quits is that old limit of 16Hz. It wasn't chosen randomly, but because it's a musically significant number. Plenty of older works had that as the lower limit of the organ pedal notes (C0) and such. Subsequently, it's influenced the mindset behind the design of recording and mastering equipment. Bad habits from the analog days may lead some to still brickwall high pass their recordings, but being capable of going that low is still there as a background influence.
Were I to settle for a downsized setup, I'd probably pick being able to do 16Hz at volume, cleanly as a good limit. While there are recordings out there that go lower, music and movies, that are best experienced in their full capability, that limit will cover the 99% some the rest represent.
Sigh, you'll find no greater amount of disinformation on hearing than from audiophiles on forums claiming what supposedly isn't audible at the lower frequencies, unfortunately.
Anyways, there is the practical aspect to consider. Halve the frequency, quadruple the needed displacement. Room gain helps there, but usually only enough to offset the natural roll-off in any design you'll be building. As you've probably already experienced, it takes a loooot to get output in the single digits without excessive distortion, an impractical amount unless you're kind of nuts. I'm the latter, yes, but acknowledge practical limits. Probably a good point to call it quits is that old limit of 16Hz. It wasn't chosen randomly, but because it's a musically significant number. Plenty of older works had that as the lower limit of the organ pedal notes (C0) and such. Subsequently, it's influenced the mindset behind the design of recording and mastering equipment. Bad habits from the analog days may lead some to still brickwall high pass their recordings, but being capable of going that low is still there as a background influence.
Were I to settle for a downsized setup, I'd probably pick being able to do 16Hz at volume, cleanly as a good limit. While there are recordings out there that go lower, music and movies, that are best experienced in their full capability, that limit will cover the 99% some the rest represent.
Don't forget ageing. When younguer I could listen to 15625Hz oscillation from tube TV sets, and I was able to distinguish when on channel (synchronized) or free running. The sound was clearly different.
Nowadays flyback transformers doesn't exist any more, but I doubth in my 53 I can ear them.
Lower frequencies are easier to ear, or almost to feel them. Remember some musicians who can't ear nothing and in place feel the sounds in their stomache (Mozzart?).
Nowadays flyback transformers doesn't exist any more, but I doubth in my 53 I can ear them.
Lower frequencies are easier to ear, or almost to feel them. Remember some musicians who can't ear nothing and in place feel the sounds in their stomache (Mozzart?).
Hi,
Useful infrasonic range from the context of theater? Well, it depends on if you want to cover 100% of content or if you're ok with 99.999% of content? Or an iteration of such a thing. I would argue that while 20hz is a common target and popular these days, the problem with it is what happens directly below 20hz depending on the design. This is also true if building for 16hz as a low point. If its the usable range, it will need to roll off naturally and smoothly, not abruptly, which means you're really going for at more like 14hz if 16hz was your goal. Or around 18hz if your goal was 20hz. Something like that, give or take.
There's truly a handful of movies that have something down to 10hz. Lots of movies have content down to 20hz. Almost every movie these days will have 30hz somewhere. It's amazing that the there's a chasm of distance between 10hz and 20hz with respect to how difficult it is to produce at high SPL and how little content exists that would take advantage of it. Maybe that will change in some more years, but maybe it won't. So it comes back down again to your preference to be able to cover 100% of content, or just 99.999% or so.
This is why there are alternatives to just building monstrous sub systems to produce infrasonics at distance and high SPL, such as vibration and/or near field systems to give that tactile response. Some do both.
Personally I'm ok with 99.999%, I don't need 8~10hz to be covered. I'm ok with 16hz and up being covered, which is what my system does. I can get tactile response from other means down to single digits. So my audible system is 16hz capable and up for many reasons that were better described above. I don't plan for synthetic 10hz waves.
Very best,
Useful infrasonic range from the context of theater? Well, it depends on if you want to cover 100% of content or if you're ok with 99.999% of content? Or an iteration of such a thing. I would argue that while 20hz is a common target and popular these days, the problem with it is what happens directly below 20hz depending on the design. This is also true if building for 16hz as a low point. If its the usable range, it will need to roll off naturally and smoothly, not abruptly, which means you're really going for at more like 14hz if 16hz was your goal. Or around 18hz if your goal was 20hz. Something like that, give or take.
There's truly a handful of movies that have something down to 10hz. Lots of movies have content down to 20hz. Almost every movie these days will have 30hz somewhere. It's amazing that the there's a chasm of distance between 10hz and 20hz with respect to how difficult it is to produce at high SPL and how little content exists that would take advantage of it. Maybe that will change in some more years, but maybe it won't. So it comes back down again to your preference to be able to cover 100% of content, or just 99.999% or so.
This is why there are alternatives to just building monstrous sub systems to produce infrasonics at distance and high SPL, such as vibration and/or near field systems to give that tactile response. Some do both.
Personally I'm ok with 99.999%, I don't need 8~10hz to be covered. I'm ok with 16hz and up being covered, which is what my system does. I can get tactile response from other means down to single digits. So my audible system is 16hz capable and up for many reasons that were better described above. I don't plan for synthetic 10hz waves.
Very best,
I can certainly feel stuff below 20 Hz on movie soundtracks, so it may be useful to have 10 Hz. For music its just annoying to hear subsonic noise, which do happen on a lot of records.
Anyway - here's my Double Bass Array measured in the main listening position, with LPF at 120 Hz :
Anyway - here's my Double Bass Array measured in the main listening position, with LPF at 120 Hz :
Hearing that instrument play live must be and impressive experience! This instrument together with the church organ show that the desire for deep bass is quite a bit older than most of us realise.Test music for you
An instrument that makes the notes you can't hear
16 Hz
Very impressive graph! I've read many good things about DBA's but my living room simply doesn't allow such a setup. My house was insulated by the previous owners and they did a poor job with sagging glass wool and cold bridges on the rain side as a result. The back wall needs to have enough breathing space to allow the moisture to evaporate so no dangerous mould can grow there.
I'll follow all recommendations and rebuild the dual 21" sub tuned @ 15Hz and I'll consider adding two sealed 15" PA drivers for tactile bass right behind the seat.
Hearing that instrument play live must be and impressive experience! This instrument together with the church organ show that the desire for deep bass is quite a bit older than most of us realise.
We're getting into the weeds here. It's not a sine wave. You're not hearing the 16Hz fundemental note even if the instrument is playing it and the speaker is reproducing it. It's a string instrument. What you are hearing are the overtones, different portions of the string vibrating at different frequencies. This is evidenced by my listening to the clip on my desktop speakers with 3" bass drivers that are likely largely impotent below 70Hz.
It makes sense. The miscalled "infrasound" region has psychological effects that can trigger anxiety and a haunted sense like you're being watched. When you're composing religious music for performance on an organ in a church, that's exactly what you want members in attendance to feel. Hence why so many pieces use the 16Hz pedal note (which happens to be around the frequency range that so triggers the "haunting" sensation at just audible levels) and many more take advantage of the organ's ability to beat two frequencies against one another to create 8Hz and even 4Hz notes to get that "Vox Dei" really going. Not being restrained by the limits of electrical reproduction, those old composers who were mighty smart about how music is heard were quick to take advantage of it. Unfortunately, production of music makes that much easier than the reproduction since we can't use two subwoofers playing higher frequencies to recreate those lower in the recordings if they haven't been cut off by the heavy filters used in recording to remove "environmental noise".Hearing that instrument play live must be and impressive experience! This instrument together with the church organ show that the desire for deep bass is quite a bit older than most of us realise.
