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  • avatar
    49 sounds
    79 posts

    Hi,

    We recently made some changes that would make that possible, but still have to discuss whether we should or not implement it.
    Maybe that would be possible with a limit to the number of sounds (to avoid unnecessarily big downloads). We'll keep you posted.

    Thanks for the suggestion,

  • avatar
    13 sounds
    393 posts

    Yes. The amplifier isn't just about volts, it's about amps. My semipro mixing desk will give out 28 volts but if I connected my speakers to it directly I wouldn't hear a squeak. At 28 volts my speakers would need nearly 4 amps to drive them properly and the mixer would balk at around 2 tenths of an amp. The speakers would simply short the mixers output and the 28v would drop down to nothing. It's like trying to turn the starter motor on a car with AA cell batteries.

    Anyhoo, good luck buchannon,

    Wibby.

  • avatar
    0 sounds
    6 posts

    strangely_gnarled wrote:
    the cheapest way getting the signal you want is from the PMW ports - if they can be configured to work up to 60kHz. All the signal processing can be programed digitally saving external circuitry which could otherwise get complicated. Whichever port you use the pi will never give out more power than what you might expect from an ipod phone jack so the amplifier will be needed.

    Okay, that is kind of what I was thinking as well. For PWM, the GPIO pins on the Pi only give out 3.3v max so that sounds like way under what I'd need.

    Thanks.

  • avatar
    13 sounds
    393 posts

    buchannon wrote:
    strangely_gnarled wrote:
    an amplifier that only needs to deliver 1-2W (providing it is not driven too far into clipping). With a typical 8 Ohm speaker that would suggest a battery or power supply of 6v minimum.

    6v minimum. Hmm.

    I know the pi has a 5v output integrated into the board, I wonder if I could get away with that. I may order a cheap speaker/amp and try it out.

    My knowledge of the pi is limited to a quick skim on google search and Wikipedia, but it seems to me the cheapest way getting the signal you want is from the PMW ports - if they can be configured to work up to 60kHz. All the signal processing can be programed digitally saving external circuitry which could otherwise get complicated. Whichever port you use the pi will never give out more power than what you might expect from an ipod phone jack so the amplifier will be needed.

    Wibby.

  • avatar
    0 sounds
    1 post

    I would seek legal advice from an attorney that specialises in music law.

    You should be credited as a writer, at the very least and would likely receive residual royalties.
    It might not be be much but for instance if this track is licensed for a car commercial we're talking big $ and you'd be entitled to a share of that. The fact that they haven't sought permission will actually put you in a better position to negotiate a bigger share of the writers royalties too.

  • avatar
    92 sounds
    37 posts

    buchannon wrote:
    dheming wrote:
    The efficiency is relatively low, but the frequency response is purported to be greater than 150kHz. Their BATPRO 2 would likely be the most appropriate starting point.

    Wow, that looks perfect but it's hard to find one for sale online. Apparently they cost $499 USD as well. Wowza.

    Taket is a very small company and I think they make everything in house. So you won't find their products being resold in many places. I've been wanting to try out their headphones for many years now.

    As an aside, Audax once made a piezopolymer dome tweeter called the HD-3P. The gold-sputtered film was held in an elliptical dome shape by a pressurized chamber filled with nitrogen. The gas slowly leaked out over time on many units and treble performance would then suffer. Not really relevant to your needs here, but that unique tweeter is what started my fascination with piezopolymer audio transducers. smile

  • avatar
    0 sounds
    1 post

    I need someone to say my dj name in any style or form. My name is " Polar Bear " and just need someone saying it, guy or girl, doesnt matter, just really looking for anything crisp sounding. If I find one, I may compensate for the time.

  • avatar
    0 sounds
    6 posts

    dheming wrote:
    The efficiency is relatively low, but the frequency response is purported to be greater than 150kHz. Their BATPRO 2 would likely be the most appropriate starting point.

    Wow, that looks perfect but it's hard to find one for sale online. Apparently they cost $499 USD as well. Wowza.

  • avatar
    12 sounds
    10 posts

    That's a really cool idea, already on it... I've been send some songs by a DJ from Brazil!!!

    Thanks for all the support guys, this community is awesome smile

  • avatar
    92 sounds
    37 posts

    An interesting variation on the standard, electromagnetic AMT is one built using piezopolymer plastic film. Taket of Japan utilizes this technology in all of their products. http://www.taket.jp/

    The efficiency is relatively low, but the frequency response is purported to be greater than 150kHz. Their BATPRO 2 would likely be the most appropriate starting point.

  • avatar
    3 sounds
    18 posts

    Are you or do you know a younger woman with a French accent? Please consider contributing to my project!

    I am offering a free gift (ebook) related to the podcast for the person who can assist.

    Many thanks!

  • avatar
    0 sounds
    6 posts

    strangely_gnarled wrote:
    it's nice to get feedback when one tries to help.

    Yep, for sure. My fault for not replying right away. I went down a google rabbit hole with those terms and then just plain forgot to get back.

    strangely_gnarled wrote:
    an amplifier that only needs to deliver 1-2W (providing it is not driven too far into clipping). With a typical 8 Ohm speaker that would suggest a battery or power supply of 6v minimum.

    6v minimum. Hmm.

    I know the pi has a 5v output integrated into the board, I wonder if I could get away with that. I may order a cheap speaker/amp and try it out.

    Thanks again for the suggestions!

  • avatar
    0 sounds
    4 posts

    Hi Guys, My name is Brokezart and I'm a upcoming Producer.

    Can someone Record me a Producer TAG i prefer a Female or Child voice but a male voice is OK!
    This is what i wanted to record: Brokezart On The Beat. Young Brokezart. Brokezart. Brokezart Tracks. Brokezart your so wavy.

    Thanks a lot!

  • avatar
    0 sounds
    4 posts

    A sample of his voice rapping. I'm not sure where the confusion is?

  • avatar
    56 sounds
    121 posts

    Colab? music creators colab with other music creators and or singers. a sample is just a sample.

  • avatar
    13 sounds
    393 posts

    My full apologies buchannon, and thanks for responding. it's nice to get feedback when one tries to help. I hope my posts in other threads explain why I jumped to conclusions, even if in this case I was clearly wrong.

    To add a bit more info that might be helpful -

    Speakers are designed for typical audio, which has a high dynamic range. That is, in order not to compress and distort the peaks a tweeter might need to handle, say, 100W peaks when the mean(average) power level is only 2 or 3 Watts. Your application doesn't need to drive those peaks, but it still requires the tweeter to handle the heat generated by the average signal level, so you are probably looking at an AMT that is rated between 20-100W, but an amplifier that only needs to deliver 1-2W (providing it is not driven too far into clipping). With a typical 8 Ohm speaker that would suggest a battery or power supply of 6v minimum. Up to 12v (or +/- 6v) would make the thing go four times louder. With a continuous sine wave a 12v peak signal would give about 9watts into 8ohms which is close to or over the limit for a 100watt tweeter, but with a pulsed signal say 200millisec on, 2seconds off this would come down to under 1watt which should be safe for the speaker but still very loud. You would have to look at the sensitivity tech spec of the tweeter to work out just how loud.

    Again, my figures are "back of the envelope" but I hope they are a good pointer.

    Good luck with your project, and I hope you keep us informed on progress.

    Regards Wibby.

  • avatar
    0 sounds
    4 posts

    Hello,

    It would be very helpful to be able to search within multiple categories simultaneously (i.e. files with wav and aiff filetypes; or files with 44100, 48000 and 96000 sample rates). It gets a bit tiring trawling through sounds to keep coming across mp3s, flacs and 8/20k files.

    Would this be easy to implement? Would other users find this helpful?

  • avatar
    0 sounds
    6 posts

    dheming wrote:
    How much acoustic power you need? Short distance or far throw? The AMT tweeter used in ADAM studio monitors is quoted as operating up to 50kHz. The Pi connected to an audio "chip" amplifier connected to a wide bandwidth tweeter would be a reasonable approach for a variable frequency ultrasonic setup. There are caveats of course, but it all depends on what you're trying to do.

    I'm trying to scare off animals with a 25khz-50khz SHORT distance throw. Maybe 10 foot max.

  • avatar
    0 sounds
    6 posts

    strangely_gnarled wrote:
    Okay, I was fooled. Buchanon is another spammer

    I am not a spammer, sorry for not responding sooner! I'm just trying to digest this stuff as I'm a complete audio noob.

    strangely_gnarled wrote:
    Firstly it requires a bigger amplifier than ceramic transducers and will not work driven directly from a GPIO output.

    I'm still trying to understand the relationship between power/voltage, sound volume, and frequency. Frequency controls pitch, where as putting voltage into the system controls volume?

    strangely_gnarled wrote:
    To reduce the chances of burning out the tweeter there are three things to watch.

    1. Do not drive with ultrasonic continuously but in short bursts. For example, a 200ms burst every 2 seconds reduces the heating by 90% but should still squeak the sh** out of squirrels.

    2. Guard against DC and all low frequency’s below, say, 10kHz with a high-pass filter. All this energy would be turned directly into heat.

    3. Never drive the Tweeter directly with square waves, either from the output of the pi or due to clipping in the amp. This could be achieved with a low-pass filter set @ ~50-60kHz. A square wave will produce about 1.4 times more heat than a sine wave of equal peak magnitude.

    #1 Makes a lot of sense.
    #2 I don't plan on using this at low frequencies like that, but I will read up on high-pass filters which I'm unfamiliar with.
    #3 Just read up on this as well, and it also makes sense about square waves driving more heat.

    Thank you all for the responses, I'm just trying to figure this all out myself as well. It sounds like I'll need a power source of some time and many more hours of reading.

  • avatar
    49 sounds
    79 posts

    Hi LeBelgeElectrod,

    We've been having similar ideas for quite a long time now, and we are in fact working on something very similar to what you propose which will allow people to provide annotations for sounds in Freesound. We'll announce it when ready, probably in the coming months.

    Thanks for the comment smile