82 Royalty-Free Audio Tracks for "Time Passing"

Recording with a universal audio apollo x and sontronics stc-1 stereo matched pair with ortf config. Recorded on may 8, 2021, at 9:30 am. Time of day when there were more birds in this area. It is a true symphony of birds. Sometimes you hear people talking in the distance and lawnmowers.

Wav-file recorded with the zoom h1 with internal microphone. A tractor is passing by the microphone multiple times mowing a big field. Recorded in a farmhouse in gasel, switzerland. Bonny orbit sound library.

Recorded this on an afternoon in the fall of 2014 at a buddhist monastery in a small coastal town outside bangkok, derived from video taken by a samsung galaxy s3. At prayer time, the monks assemble and one monk leads with a microphone. This recording reflects the somewhat tinny eq of that sound system, and also includes some dimly-heard background noise from the outside environment (e. G. , passing vehicles).

One by one, five cars are crossing the soundfield on a straight desert wet road. We can ear them a long time before and after. Motors, air movement and weels on water. Some residual rain drops and faraway rooster after car n°4. France, nov 2022. Recorded with 2 em 172 in ab setuprecorded on zoom f3wave stereo, 24bits 48khz.

This is a foghorn-like sound that i created using an accidentally recorded poot from a friend. I stretched the sound bite a few times while lowering the pitch, added a couple different reverb effects, and then finished it with some parametric eq, raising the bass, and using a low pass filter to cut out the high frequencies. If you would like the original poot sound, i have also uploaded it as fart sound 1.

This is a background sound i've created designed to imitate the noise produced by a vast collection of typewriters being worked on in a large warehouse environment. All the noises within in have been taken from freesound. There are 8 different typewriters here. On some channels i stuck a lo pass and some big room reverb, and on others i added a little compression to bring them to the forefront. The whole had a hard limiter to -6 on the top.

Field recording from sault ste marie, mi. Noon-hour traffic on a 25 mph street cars passing over a bridge. Little or no wind noise. Recorded on a tascam 4-track with a sure hi-z mic, onto a maxell cassette. Circa 1990'sconverted to ; 16bit 44. 1 dual mono (not true stereo).

Recorded outside louisville city hall next to the courthouse at a time with lighter traffic. Recorded around 9am on 1/30/2018. Recorded with a sound devices mixpre-3 with two rode nt5's in a x-y setup at an angle to emphasize the sound of footsteps on the sidewalk.

This sound is a tribute to a good friend of mine that passed away last year. Where ever you are now in this universe brother, we all miss you and love you forever. Scot ryan parolinipeace. This sound or sounds was created through the help of vst's, time shifting, parametric eq, cutting, sampling, layering and many other methods of sound manipulation.

My mother's house is the keeper of a trend by sligh grandfather clock named bonnie. Each time i pass by it, i admire the sound. I decided to capture it. It's mostly a clean recording outside of the occasional bird chirp or atmospheric sound. Easy to clean up, edit, and loop. Enjoy!. Recorded using an oktava mk-012-01 through a focusrite scarlett 2i2 audio interface; captured at 96k 32bit float, and bounced down to 48k/24bit in pro tools on windows 11. The mic was placed about two inches away, perpendicular to the face of the clock with the dial window open. The only processing i applied was a fabfilter proq3 48db/oct low cut at 110hz to eliminate of some of the room/ac rumble.

Assymetric ticking noise. Sounds like the ticking of an analogue counter. A single clock tick was placed on two seperate tracks in order to control the time interval between ticks. One of the tracks was pitch shifted to create the sound of two, slightly different ticks. Both tracks pass through a tight chorus filter and a delay tap to recreate a slight sense of springiness and rattle as the "counter wheels" tick over. Created in flstudio with one audio clip, fruitydelay2, fruity fastdist, fruity parametric eq 2, fruity chorus and equo.

I used 2 low frequency operators (lfo) on a low pass filter (24db) on a generic pink noise sound with medium resonance settings, one of these lfo's was manipulating the other one with a random ramp, to make it sound more diverse and realistic. I put an aditional long envelope on the q (resonance) also, not to mention some chorus at a low tempo to make it kinda binaural with a stereo delay at a short time setting. . . I hope you enjoy it!.

A patch with nonlinearcircuits jerkoff ("chaos circuit based on the jerk equation and its electronic implementation by jc sprott") in the center. I had a question that needed an answer. Is jerkoff a stable lfo when not using the input to disturb the rythm?my answer is. It can be relatively stable, but sometimes it is wobbling around. The recording is from a wobbly jerkoff. One output to osc cv in and another to a vcf vc in. The third output goes to a comparator. The comparator generates a trigger every time the cv is passing the threshold level.

A very long stereo ortf recording of the main square (place de la réunion) of mulhouse (france) made with a pair of akg c451 and an edirol ua-101 sound-card. German children crying most of the time, men speaking, cars passing slowly, soft rain about the middle of the recording, siren and church bell at the end. I would be glad if you let me know when you appreciate/use this recording. Enjoy.

A sample i made years ago. Pitched way down to create a seamless loop of ambience with two automated notch filters and an automated bandpass filter on flstudio's pmeq2. If required, i can process this sound again with different filters for those who request it. This is not the fully opened sound. Hope you enjoy ^_^~byngsies.

I sold my giant couch, and two professional movers came to pick it up. Before they moved it, they whipped out a huge roll of clear plastic, and expertly passed it around and around the sofa until the whole thing was wrapped. The noise the wrapping made was astonishingly loud and echoey in our place, and sounded very. . . Uh. . . Science fiction-y. Recorded on my samsung note 20 phone, and some movers' mumbles included, so not desperately high quality -- but maybe someone can use part of it for a wizard rending the space time continuum with a sharpened wormhole, or some such. :-).

While the world is holding its breath, waiting for the covid-19 to pass. . . The soundscape is different. Here in illinois, where we have a mandatory, stay at home order, the sounds of the morning winds and birds seem lonely. . . This was recorded on sunday march 29th, 2020. Usually this time of morning would also feature, people walking and talking on the sidewalk, more car traffic and church bells. . . . Recorded with the zoom f-4 recorder. The microphone was a sennheiser mkh-8060 literally pointed nearly straight up at a budding tulip poplar tree. The dominant feature is the constant river of whooshing wind. . . . . Seemingly underscoring the plight that is upon us.

I was sitting in my car in the city centre of glasgow scotland waiting for a member of my family, so to pass the time i got out my little canon powershot a460 digital camera, wound down my window and recorded the sound of the heavy traffic driving past my car. This sound of mine is for anybody to use, no credit needed, but it would be fun if you can let me hear how you used the sound, if possible, that would be fun. Here is a link to the type of licence i use. Http://creativecommons. Org/publicdomain/zero/1. 0/.

This is my first upload: a short walk between the stalls of the vismarkt in groningen, netherlands. Is was a splendid and sunny saturday morning, about 9. 30 am, may 7th 2016. In the first part of the recording, a garbage truck is already cleaning up. Fish crates are being piled up and money is exchanging hands. As the name of the market square suggests, the stalls are filled with fresh north sea and wadden sea fish. But i also passed stalls where cheese, meat and spices were sold. Business was thriving at the time of the recording. The groningen vismarkt is broadly recognized as one of the finest food markets in the country. I used an iphone with a zoom iq5. As said, this is my first recording, so please bear with me. . . I intend to learn.

Here's some more of that young couple next door. For this one, they probably went 15+ minutes. Their libido must be really high for this day/night. From my listening, it seems like they were not doing it in bed the entire time. They must have used other furniture and played around in different positions. From 3:30 or even before that is when they start. Passed 5:00 is when the woman starts to moan loud. 14:55 is when they finish. 16:07 guy says i'm tired. Note that the original audio had more bed and furniture creak noises, almost 30 mins long, and some of their chats cut out. Also note that some of the noises left in on the good parts may not be sex noises. This was edit and shorten with audacity.

A complete trip on métro (subway) line 9 of the paris subway system, from the alma-marceau station to the havre-caumartin station. Starts with descent into the métro station and ends climbing up the steps back out at the destination. One train is allowed to pass, at about the 1-minute mark, as we wait on the platform, and an announcement giving the times for the next trains can be heard. The ride on the following train begins at around the 2-minute mark. There are two loud sounds between about 9:10 and 9:20 and some loud low-frequency wind noise at around 10:40 (as we leave the métro station and return outside), so beware. Recording with zoom h4n, originally 96 khz/24 bits, uploaded as mp3 320 kbps because the wav was so big (almost 500 mb).

This sound or sounds was created through the help of vst's, time shifting, parametric eq, cutting, sampling, layering and many other methods of sound manipulation. Follow me on youtube for future tutorials and music. Https://www. Youtube. Com/channel/uc3f2acuv1q0hsuaxqqwotrq-------------i make sounds for freesound. Orgi obviously don't get paid anything for uploading and the premise of using freesound. Org is to share sounds for free to everyone. If you could help me make this a sort of go fund me donation so i can continue doing what i love. Any amount donated is greatly appreciated and words can't show how much i appreciate you. Thank you for reading. Https://paypal. Me/pools/c/81iraceqx0.

The same as my other fire whoosh sound, but i used a hi-pass eq at the 50hz mark to take out some of the "mud. ". --. This is a quick fire sound i made using qubodup's "swing 25" public domain/cc0 upload on this site. It's a bamboo stick swinging, which i layered and toyed with to get the results here. For those curious, here are the steps. * i took the file into reaper, and slowed the file's playback rate to 31% of the original. * i then duplicated the file three times, for a total of 4 tracks. * track 1 (lowish gas-burner sound):- reverb (drum-room impulse response, a medium-sounding reverb with a slight deadness to it. In free impulse loader reverberate le, stretched impulse to 150% and set attack time to 0. 218s). - eq (-8db bandpass near 200hz, rising back to 0 by the 1k mark. Low-pass applied at 5. 8khz). * track 2 (lowest of sounds, like a bassy gas-burner):- chorus effect. That's it. (specifically acon digital multiply, a free plugin, set to the "romantic" preset). * track 3 (not as low as track 2, but closer to track 2 than 1)- reverb (a large hall impulse response. No adjustments, ie. No increased attack or stretching like for track 1. ). -chorus doubler (free plugin duet, preset: "basic doubler. " same effect as if i had doubled the track and pitched one up 6 cents. ). - chorus (free plugin acon digital multiply, preset: "romantic. "). * track 4 (most flame-thrower, whooshy of tracks. )- reverb (impulse response says "hall medium," but it's a thick, even echo from start to finish. Makes the sound go from its default "whoosh" to a flamethrower noise. - chorus doubler (duet again, preset: basic doubler). - chorus (acon digital multiply, preset: "romantic. "). Master bus:. - compressor (tdr kotelnikov mastering compressor, the free successor to the tdr feedback compressor ii. Preset: punchy. Thresh: -20. 9, soft knee: -1. 5, ratio: 2:0:1, attack: 7. 0 ms, release peak: 165 ms, release rms: 165 ms, makeup: 1. 5 db, output: 2. 0 db. That's it.

I videoed this sound of a subway train in glasgow scotland on the famous "clockwork orange" train as they are called. I used my canon powershot a460 digital camera to video this, i simply took the sound from the video. I was lucky enough to get a good run on this with just a few poeple on board, so there wasn't any other sound apart from the train, the only time you here some movement of feet is when the doors open. Please note, anybody is free to use this sound, you don't have to credit me, but it would be fun to hear how you use my sound if possible. :) here is the link to the type of licence i use. Http://creativecommons. Org/publicdomain/zero/1. 0/.

This is a quick fire sound i made using qubodup's "swing 25" public domain/cc0 upload on this site. It's a bamboo stick swinging, which i layered and toyed with to get the results here. For those curious, here are the steps. * i took the file into reaper, and slowed the file's playback rate to 31% of the original. * i then duplicated the file three times, for a total of 4 tracks. * track 1 (lowish gas-burner sound):- reverb (drum-room impulse response, a medium-sounding reverb with a slight deadness to it. In free impulse loader reverberate le, stretched impulse to 150% and set attack time to 0. 218s). - eq (-8db bandpass near 200hz, rising back to 0 by the 1k mark. Low-pass applied at 5. 8khz). * track 2 (lowest of sounds, like a bassy gas-burner):- chorus effect. That's it. (specifically acon digital multiply, a free plugin, set to the "romantic" preset). * track 3 (not as low as track 2, but closer to track 2 than 1)- reverb (a large hall impulse response. No adjustments, ie. No increased attack or stretching like for track 1. ). -chorus doubler (free plugin duet, preset: "basic doubler. " same effect as if i had doubled the track and pitched one up 6 cents. ). - chorus (free plugin acon digital multiply, preset: "romantic. "). * track 4 (most flame-thrower, whooshy of tracks. )- reverb (impulse response says "hall medium," but it's a thick, even echo from start to finish. Makes the sound go from its default "whoosh" to a flamethrower noise. - chorus doubler (duet again, preset: basic doubler). - chorus (acon digital multiply, preset: "romantic. "). Master bus:. - compressor (tdr kotelnikov mastering compressor, the free successor to the tdr feedback compressor ii. Preset: punchy. Thresh: -20. 9, soft knee: -1. 5, ratio: 2:0:1, attack: 7. 0 ms, release peak: 70 ms, release rms: 165 ms, makeup: 1. 5 db, output: 2. 0 db. That's it.

Hi. This soundfile was recorded on 03. 06. 2017 in szczecin, nw poland (gumience district to be precise). The time of this recording is from around 3 a. M. (when the sun was allready rising) till around 7:30 a. M. What's funny about that, is that i turned my recorder on and layed it on the windowsill (display up) on altitude around 5 meters (first floor), (the recorder is facing ne direction) because the birds were allready going crazy!, and after some time i felt asleep, and the recorder was left on. There are many many kinds of birds around, cause there is a big cementery near by, with lots of trees, and some wild fruit orchard too. I had this one moment, when the birds were so active, that let's say they spinned it me around, and worked me up to a beautifull spiritual moment with their sounds, and then i felt asleep. Later through the recording you can hear me snoring, you can hear my alarm clock going on (and that haven't woken me up too;). The bass resonance of cars passing by makes this recording a bit heavy in some places, and the wind made it's mark too, but that shoudn't be a big of an issue here. As i listen to it now, so much things happened while i was asleep. . . [ 3:30 a. M. !: some people are singing and speaking, and you can clearly hear one of them saying: "kurwa, grubo", which means - "f**k, heavy". Later on, the neighbours weren't sloppy too;). Hearing such recordings doesn't give you the liminous feeling of the place where it was recorded. You only get audio here, not the vision, the light, the brightness, the movement, the actions, and the space, the physical elements, only the best can imagine (so if you don't have such an imagination, pm me and i can send you a photo of the place where all this took place). Anyway, i hope that the birds will keep rockin' their solos, and the bees will keep visiting all the flowers around forever! (who knows, i might become one of them sometime;). Thanks and have a good listening session. Szymon.

I was just going through my sounds, when i decided "hey. . . I'm gonna release this. " so here you all go! i'm really proud of how this turned out. This, as you can tell, is a deep eerie ambience loop. It can be used for anything you want. I like to leave things up to the imagination of the audience. How it was made:. Software used:-fl studio 20-harmor-harmless-fruity parametric eq 2-valhallaroom. So basically what i did was get a low pitch sawtooth waveform, put it through some effects like harmonization, a low pass filter with high resonance, a phaser, and a load of distortion. The main synth is made with harmor. (yes, this is all one synth. It just has a lot of dynamics. ) i then processed it with some eqing. What made this sound what it is would be the reverb. I put 2 layers of valhallaroom on the synth. One has a very short decay time, and gives it texture. The other gives it the atmosphere. To add some more depth, for the final touch, i layered a sub-bass underneath it. Which is just a low sine-wave with reverb on it, which i used harmless to make. I hope you enjoy this!.

This is a sci-fi ambient drone sound i made. It's creative commons cc0, so please treat it as public domain. You can use it in any commercial or non-commercial media for free, no restrictions. For those curious how i made this, i took a quick 8-second drum loop from my pocket operator po-33 (ko) and ran it through a free time-stretching/pitch-shifting program called akaizer. The program's based on old samplers like the akai s1000 that had extremely artifact-heavy time-stretching and pitch-shifting features. If you slow a sound down enough, the final product tends to sound harsh and electric. Akaizer turned my 8-second drum loop into 2 minutes and 38 seconds of harsh, bassy noise, pretty damn close to the final. Then i imported the file (we'll call it file a) into reaper, my daw. Track 1 has reaeq with a high-shelf acting like a low-pass. Its curve is set at 1386. 2 hz, gain at -inf, and bandwidth at 2. In retrospect, i have no idea why i didn't use a low-pass. Track 1 has a send to a blank track 2, which has a fab-filter pro-q 3 high-pass filter with a 12db slope. It's at 320. 57hz, q is 1. 096. After the eq, track 2 has valhalla shimmer set to the black hole preset with no changes. Track 3 is the default file a with valhalla shimmer on the black hole setting, but with two tweaks. Low-cut is at 30hz, high-cut is at 6630hz. Everything else is the same. That's followed by fab-filter pro-q 3 with these eq settings:-0. 72db at 69. 463hz, q at 1. 007. -1. 11db at 536. 64hz, q at 1. 013, dynamic eq (click "make dynamic" and leave everything as-is). The point of this dynamic eq is to give a slight drop in gain in the 500hz region, which tends to get muddy in larger mixes. I wasn't sure if i'd use this for a larger project, and i didn't want build-up in that region from the already large-sounding track 1 and 2. The ocassional eq drops here also adds a warble to the final mix that helps sell an analog, electrical sound. +0. 85db at 3697. 3hz, q at 1. 009. This is to add subtle airiness to the drone. It seems weird to have "airiness" in the 3-4k region, but it's the sort of rumbliness of the sound traveling away and dissipating in the atmosphere after the lowest drone sounds. My volume fader settings for all 3 tracks:. Track 1: -8. 59 dbtrack 2: -6. 46 dbtrack 3: -6. 43 db. On my master bus, i have izotope imager 9 with these settings:. Band 1: width at -100 (mono) for 59hz and below. Band 2: nothing at 60hz to 525hz (width at 0). Band 3: width at 48. 1 for 526 to 1. 4khz. Band 4: width at 49. 4 at 1. 4khz and above. Stereoize is set to 6. 4ms on mode i. And that's it! no compressors or limiters anywhere, since i liked how dynamic the actual tracks were and i figure you can always add your own compressor or limiter to the final if you want. I've also added the original po-33 drum loop on my page, as well as the loop after it was run through akaizer but before it hit reaper in case you want to do your own processing. Enjoy :).

Calm ambient track. Winter woods / pinewood february 12. 41 pm (noon) in the netherlands near village giersbergen. Bram’s admin request-text and my answer in audio. Hello freesounders,it happens very infrequently that i post requests. However, i have an extraordinary sad reason to do so today. I don't want to go into detail in this public forum, but someone incredibly important and incredibly young in my life and my wife's just passed away. I am thus looking for an extra long recording of a peaceful "forrest ambience" to play during the good-bye ceremony. Something with some birds and perhaps some wind through the leaves,. . . . Currently the ceremony is planned for april 6th so i would need this before then. I know i can look through freesound, but i would like something specifically recorded with this in mind, something we will be able to listen to later as well, remembering this important and sad time in our life. . . Yours in grief,- bram & familywhat you hear;general-noise; soft wind in woods, sometime a bit increasing. A far kid at the edge of hamlet giersbergen. Far hum of the woods. Remark that the far high altitude planes are on a very lo noise level. Off and on craws and woodpeckers. 00. 00-02. 18 clean background-sound02. 18-06. 57 far high altitude plane- 04. 08-05. 42 people passing06. 05- 08. 13 clean background-sound- 07. 15-08. 12 woodpecker08. 16-10. 33 far high altitude plane10. 33-11. 44 clean background-sound- 10. 44-11. 32 (far) woodpeckers11. 33-12. 53 far police serine12. 55-14. 11 clean with some far yelling kids and woodpeckers14. 15-16. 14 far high altitude plane16. 14-26. 11 clean background-sound with some friendly increasing wind gusts- 23. 06-23. 56 woodpeckers- 25. 53-26. 08 woodpecker26. 08-end far high altitude plane and people. More recordings here search: giersbergen. About the area, national park loonse en drunense duinen. (text by irma de potter,ranger of this area) dutch website: https://www. Natuurmonumenten. Nl/natuurgebieden/nationaal-park-loonse-en-drunense-duinen. In the loonse en drunense duinen you will find forest, heathland and especially a lot of sand. It is one of the largest shifting sand areas in western europe. The wind can blow undisturbed in many places, resulting in an ever-changing landscape. By purchasing it in 1921, it has been protected for 100 years and we can still enjoy this brabant sahara today. You can roam freely on the sand plain. So there is plenty of room to explore extensively. Marvel at the submerged trees, enjoy the chirping field crickets and quench your thirst at one of the many cafes or restaurants on the edge of this nature reserve. Walking, cycling or on horseback: it's all possible here. With the wind in your hair and the sand in your shoes. You may even come across the sheep herd. The sheep keep the heath short and eat away saplings. This is how they keep the area open. The loonse en drunense duinen still has 270 hectares of shifting sand. That sand creates rather extreme conditions: the soil is dry and nutrient-poor. The difference in temperature between day and night can be as much as 50 degrees celsius. This ensures a unique flora and fauna. The animals and plants have adapted or feel at home in drought, aridity and temperature fluctuations. Sand sedge and various lichens, for example. And the viviparous lizard, sandpit beetles and sand bees. All species that love sand. In the last ice age, the polar winds blew sand from the north to brabant, where it remained in thick packages. For a long time this sandy plain was covered with primeval forests. Until the fourteenth century the trees were felled by people. They used the wood as fuel. The bare plain was filled with heather, where the farmers grazed their cattle. This intensive grazing and the sod cutting of the soil depleted the soil. This gave the sand free play. For a long time, the sand was a major problem for the residents. Villages and fields threatened to disappear under it. Trees were planted to stop the advancing sand. You can still see the traces of this today: find the submerged trees that only peak above the sand hills with their crowns. Date/time: february 15th tuesday 2017, start 12. 44 pm. Weather: 13c, clear sky, wind se 2-3bft , 1023 hpa. Mic pointed ne. Location; soft-wood-forest giersbergen (drunen), national park “loonse en drunense duinen”, drunen, noord-brabant, netherlands (holland), europe geo 51. 65566 5. 15774. Gear chain: sennheiser mkh30/50 ms, in rycote cyclone small, windjammer > sound devices 302 >tascam dr-100 mk2. Low cut 140hz 6db/octave. Level around -33db for background. Decoded mid-side to stereo.

This is the audible annunciation found at all intersections with traffic lights in paris, france. It announces the condition of the traffic lights for pedestrians who are blind or with impaired vision. The annunciation is turned on by pressing a button on the traffic light pole. When the crosswalk sign is red (do not cross), the recorded annunciation is always "rouge piéton" ("red light, pedestrian"), followed by the name of the street that the crosswalk crosses (in this case "rue d'antin," the quiet side street where i recorded this). This repeats over and over until the crosswalk changes to green, at which point there is a two-second trill tone followed by a repeating bell tone. The bell tone is one bell, followed by two bells, repeated four times, followed by a very brief pause, and then the sequence is repeated again. This continues until the crosswalk changes back to red, at which point the "rouge piéton" message resumes. The annunciation continues for at least one cycle of the traffic lights and then stops, unless the button is pressed again. The audio quality of the annunciation is very poor even in real life (it sounds like a wax cylinder recording or something), and can be difficult to understand. This recording accurately captures the poor quality of the annunciation. The volume of the annunciation is also adjusted dynamically based on ambient noise, so there is a slight change in volume on this recording as the system apparently reacts to noise from traffic or something. There is a weak background noise that sounds like some sort of machine, but it wasn't coming from the traffic light and i don't know the source. The recording starts with the crosswalk red, then at about 18. 3 seconds it changes to green, then it changes back to red at about 53 seconds. A car passes at around 48 seconds. Recorded with a zoom h4n, stereo 96 khz / 24 bits, built-in mics, from about ten inches below the tiny speaker in the crosswalk sign housing.

A few cycles of my dad's home oxygen machine with a ticking battery operated clock in the background recorded in the early morning in the living room with lifecam hd3000 webcam at the end of about 16 feet of usb cable dragged out of my bedroom. He's about 6 feet away, i was with my back to the room with my camera pointed at my chest so he wouldn't think i was filming. It would seem this is the first and only oxygen machine on freesound. A full cycle seems to last from between 7 to 10 seconds. From wikipediaoxygen concentrators typically use pressure swing adsorption technology and are used very widely for oxygen provision in healthcare applications, especially where liquid or pressurised oxygen is too dangerous or inconvenient, such as in homes or in portable clinics. Oxygen concentrators are also used to provide an economical source of oxygen in industrial processes, where they are also known as oxygen gas generators or oxygen generation plants. Oxygen concentrators utilize a molecular sieve to adsorb gasses and operate on the principle of rapid pressure swing adsorption of atmospheric nitrogen onto zeolite minerals and then venting the nitrogen. This type of adsorption system is therefore functionally a nitrogen scrubber leaving the other atmospheric gasses to pass through. This leaves oxygen as the primary gas remaining. Psa technology is a reliable and economical technique for small to mid-scale oxygen generation, with cryogenic separation more suitable at higher volumes and external delivery generally more suitable for small volumes. [1]at high pressure, the porous zeolite adsorbs large quantities of nitrogen, due to its large surface area and chemical character. After the oxygen and other free components are collected the pressure drops which allows nitrogen to desorb. An oxygen concentrator has an air compressor, two cylinders filled with zeolite pellets, a pressure equalizing reservoir, and some valves and tubes. In the first half-cycle the first cylinder receives air from the compressor, which lasts about 3 seconds. During that time the pressure in the first cylinder rises from atmospheric to about 1. 5 times normal atmospheric pressure (typically 20 psi/138 kpa gauge, or 1. 36 atmospheres absolute) and the zeolite becomes saturated with nitrogen. As the first cylinder reaches near pure oxygen (there are small amounts of argon, co2, water vapour, radon and other minor atmospheric components) in the first half-cycle, a valve opens and the oxygen enriched gas flows to the pressure equalizing reservoir, which connects to the patient's oxygen hose. At the end of the first half of the cycle, there is another valve position change so that the air from the compressor is directed to the 2nd cylinder. Pressure in the first cylinder drops as the enriched oxygen moves into the reservoir, allowing the nitrogen to be desorbed back into gas. Part way through the second half of the cycle there is another valve position change to vent the gas in the first cylinder back into the ambient atmosphere, keeping the concentration of oxygen in the pressure equalizing reservoir from falling below about 90%. The pressure in the hose delivering oxygen from the equalizing reservoir is kept steady by a pressure reducing valve. Older units cycled with a period of about 20 seconds, and supplied up to 5 litres per minute of 90+% oxygen. Since about 1999, units capable of supplying up to 10 lpm have been available.

Recorded in my dad's bedroom with lifecam hd3000 webcam. This is a much better recording than my previous oxygen concentrator file, as i hauled my desktop into the bedroom at the other end of the apartment where the machine now is, when i was home alone. The webcam is on the bed about 3 or 4 feet from the machineat the beginning of the file you hear me flip the big switch and the machine comes on with a long on beep and thumps. I edited it to start then. At 00:1. 8 what i suspect is the water pump comes on, though i may be wrong. That's when the gurgling starts though. The machine has a small reservoir for distilled water to moisten the airflow. A cup or two lasts several daysyou'll hear various hisses and thumps in a 15. 6 second cycle as it runs. At 03:03 i flip the big switch to shut the machine off, and it bubbles and gurgles away for the rest of the file, as water i assume slowly perculates back into the reservoir, the bubbling getting quieter and quieter until it doesn't even sound like bubbling anymore, until it finally ticks to a stop. At 03:16 you hear me step as i get my foot loose from the mic cord lol. At 04:13 the furnace shuts down as a car finishes going by outside in the bass register, faint traffic noises and the furnace being the only background noises you'll hear aside from my moving around a couple times, and a faint bluejay at the end. At about 07:00 you can barely hear the machine anymore, but i could hear a faint ticking with my own ears. At 07:04 the furnace comes back on. At 07:08 you'll hear a bluejay faintly calling outside and a car going by outside after, which finishes the file at 07:20. I edited out my walking to the computer to shut the recording down. From wikipediaoxygen concentrators typically use pressure swing adsorption technology and are used very widely for oxygen provision in healthcare applications, especially where liquid or pressurised oxygen is too dangerous or inconvenient, such as in homes or in portable clinics. Oxygen concentrators are also used to provide an economical source of oxygen in industrial processes, where they are also known as oxygen gas generators or oxygen generation plants. Oxygen concentrators utilize a molecular sieve to adsorb gasses and operate on the principle of rapid pressure swing adsorption of atmospheric nitrogen onto zeolite minerals and then venting the nitrogen. This type of adsorption system is therefore functionally a nitrogen scrubber leaving the other atmospheric gasses to pass through. This leaves oxygen as the primary gas remaining. Psa technology is a reliable and economical technique for small to mid-scale oxygen generation, with cryogenic separation more suitable at higher volumes and external delivery generally more suitable for small volumes. [1]at high pressure, the porous zeolite adsorbs large quantities of nitrogen, due to its large surface area and chemical character. After the oxygen and other free components are collected the pressure drops which allows nitrogen to desorb. An oxygen concentrator has an air compressor, two cylinders filled with zeolite pellets, a pressure equalizing reservoir, and some valves and tubes. In the first half-cycle the first cylinder receives air from the compressor, which lasts about 3 seconds. During that time the pressure in the first cylinder rises from atmospheric to about 1. 5 times normal atmospheric pressure (typically 20 psi/138 kpa gauge, or 1. 36 atmospheres absolute) and the zeolite becomes saturated with nitrogen. As the first cylinder reaches near pure oxygen (there are small amounts of argon, co2, water vapour, radon and other minor atmospheric components) in the first half-cycle, a valve opens and the oxygen enriched gas flows to the pressure equalizing reservoir, which connects to the patient's oxygen hose. At the end of the first half of the cycle, there is another valve position change so that the air from the compressor is directed to the 2nd cylinder. Pressure in the first cylinder drops as the enriched oxygen moves into the reservoir, allowing the nitrogen to be desorbed back into gas. Part way through the second half of the cycle there is another valve position change to vent the gas in the first cylinder back into the ambient atmosphere, keeping the concentration of oxygen in the pressure equalizing reservoir from falling below about 90%. The pressure in the hose delivering oxygen from the equalizing reservoir is kept steady by a pressure reducing valve. Older units cycled with a period of about 20 seconds, and supplied up to 5 litres per minute of 90+% oxygen. Since about 1999, units capable of supplying up to 10 lpm have been available.