sound amplification

[hexe]

Hi.I need to record some enviromental sounds (not speech).I tried my pc's microphone but it cannot even record sounds i can hear without any device.I want to hear barely noticable sounds loudly.Sound quality and distortion is not that important.Mic wil be used indoors and sounds will be recorded to pc.Can you offer me any simple solutions.I dont know much about electronics.I can make a pcb if you send schematics or simple things like that.Thanks

 

[Sceadwian]

If you don't know much about electronics you're better off buying a commercial device.
Something like https://www.amazon.com/Sonic-Super-...H8G4/ref=sr_1_1?ie=UTF8&qid=1318892982&sr=8-1
Would work for you, 30 dollars is not expensive and even if that isn't sufficient simply adding a parabolic reflector will increase range and directionality dramatically.

 

[Reloadron]

The guy in these forums who would likely have a good solution is AudioGuru who hopefully will catch this thread. That said, with the PC are you going into the mic input? Does the PC have the options of Line or Mic input? You may want to give this link a read. Years ago I built a pretty simple amplifier with a home brew parabolic dish. It was directional but you could hear and record the birds in the trees.

<EDIT> Sceadwian beat me with an off the shelf commercial suggestion which is a damn good idea as pre amps are pretty cheap and spare you some grief. </EDIT>

Ron

 

[audioguru]

It is simple to make a high gain preamp for a microphone. But what about loud motorcycles and jet airplanes?

 

[transistor495]

I think op wanted to use it indoors.

 

[hexe]

Sorry for replying lately

with the PC are you going into the mic input? Does the PC have the options of Line or Mic input?

my pc has mic input

If you don't know much about electronics you're better off buying a commercial device.
Something like http://www.amazon.com/Sonic-Super-P...H8G4/ref=sr_1_1?ie=UTF8&qid=1318892982&sr=8-1
Would work for you, 30 dollars is not expensive and even if that isn't sufficient simply adding a parabolic reflector will increase range and directionality dramatically.

Years ago I built a pretty simple amplifier with a home brew parabolic dish. It was directional but you could hear and record the birds in the trees.

i need an omnidirectional mic

It is simple to make a high gain preamp for a microphone. But what about loud motorcycles and jet airplanes?

I want to record footsteps or more accurately people on the stairs of my apartment.An audio detection software (like http://www.zonetrigger.com/sound-detection/) will email me recordings whenever it detects someone so that i will know if someone is waiting for me inside the building.It may sound paranoid but there were some incidents around here lately.

I bought a cheap microphone and made some recording with audacity software

audacity software (to open the recording):

http://audacity.sourceforge.net/

recording:

http://www.2shared.com/file/uvcP35JD/1_online.html

Recording is amplified with 35db gain.I cant use audacity for my purpose because it doesnt amplify sound realtime.

My flat is on the second floor.In the recording i descended to the ground floor (at about 38th second) and then began climbing.

I want to be able to hear footsteps two floors up and down.Cheapest solution seems to be making a pre amp circuit.For a much more louder and clearer recording which simple preamp circuit do you advice?

specifications of the microphone i used for recording:

omni-direction
output impedance:1.4k+-30%

frequency response:50~16khz

sensitivity:-58db+-2db

operating voltage:1v~10v

current consuption:0.8ma max

s/n ratio 40db or more

 

[alec_t]

Check this forum link :-
https://www.electro-tech-online.com...20829/?highlight=microphone+pre-amp+amplifier

 

[Reloadron]

If your PC has a serial port (RS232) or if you can buy a good USB to RS232 dongle why not place a PIR sensor (motion sensor) in your flat? If any motion IR is detected it can easily send you a SMS text as well as an email. This can be very easily done. On another note if I had the problems you worry about I would move! A motion sensor would be much more simple to my simple way of thinking.

Ron

 

[hexe]

Those sensors would do excellent but there are other people living in the apartment they would trigger those sensors too.Also i cannot plant anything to other floors just outside of my door because of my neighbors.

My thought is to listen recordings and see if someone entering building gets inside their flats or they dont.There arent many people staying in the building so i hope there wont be many recordings.I will set softwares sensitivity low.Before entering the building i will download recordings to my cell phone and listen them.