Transforming Android devices to perfect real-time audio equalizers... - General Topics

Android devices became so powerful that they should easily be able to run digital room correction software.
The benefit of being able to run digital room correction (DRC) on an android phone, is that it will allow correcting for acoustic anomalies in car audio playback.
When you play audio in your car, the frequency response that you hear is not flat from 20hz to 20khz (as it should). The speakers/amplifier/HU/car-acoustics worsen the frequency response.
A digital room correction software can dramatically help to make frequency response much closer to ideal in your car. So your audio will sound much much better.
In order to do DRC in your car, what you need to do first is measure the frequency response in your car from 20hz to 20khz (using a log sweep and a microphone. There are many free softwares that will allow this). Then you feed the frequency response recording of your car, to the DRC algorithm (there is a free one that I use), and it will create a filter. If you run your music through this filter, it will solve many of the frequency response anomalies that you have in your car. It's like the best equalizer device you can think about.
In use DRC in order to correct the acoustics of my home audio system. Here is an example of what DRC did for my home audio system:
This is the frequency response that I got in my room before using DRC (I am showing here only the frequency response below 200hz. Ideally it should be flat, since I'm playing a log sine sweep where each played frequency has the same SPL level):
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You can see all the dips and peaks. The sound is not very good when your frequency response looks like this.
After I fed this information to the DRC algorithm, it created a filter to correct the frequency response anomalies. This is how the frequency response behaves in my room after applying the DRC filter:
Yes, a dramatic effect !!
DRC can do this for car audio too. The only problem is that you need to run the music through a software that can do real-time convolution (or in other words, to take the DRC filter and use it to change your music in real time). For windows there are several music players that can do this (like Foobar2000), but for Android I couldn't find a real-time convolver. If there was a real time convolver for android, we could play our music through the android device (conneted to the car audio system) using the convolver, and get much much improved sound.
Does anyone know of a real time convolver for android ?
For more reading abour DRC:
http://drc-fir.sourceforge.net/

Related

Headphones equalizer available for HTC’s Pocket PC phones!

Anyone having read my article “Everything you will ever need to know about the power consumption of Pocket PC audio players" knows x50mix and UdaEq, hardware audio equalizers for Dell Axim and Compaq / HP iPAQ devices (and some other) used with wired headphones. Unfortunately, they can only be used together with wired headphones – neither built-in speakers nor A2DP Bluetooth ones will be affected.
Hardware equalizers have the BIG advantage of not adding any additional CPU usage, unlike software equalizers used by most multimedia players. Therefore, if you need to have absolutely the best battery life, you use wired headphones and you won’t suffer from the equalizer’s resetting upon reinitalization of sound hardware (switching to next track in non-cross-fade- or gapless playback-capable multimedia players), make sure you give it a try.
HTC has also released its own equalizer compatible with most (but not all) HTC Pocket PC Phone Edition models. It’s available HERE (mirror HERE). After installing, manually create a link file to \Windows\Equalizer.exe. I’ve done this for you (it’s HERE) – just copy the file to \Windows\Start Menu\Programs or anywhere underneath it.
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It also has some presets, and you can define / save /reload your own as well (screenshots: 1 2)
Finally, it allows for setting the microphone level or enable AGC as well.
Note that it isn’t compatible with Smartphones at all as can be seen in THIS and THIS screenshots. In addition, it won’t work with some HTC Pocket PC phones either; for example, the HTC Wizard (I’ve tested it with XDA Mobile 6 Release 3 – it MIGHT work with other versions)
Also note that there is a catch: when you play back a song that closes and reopens the channel (WMP is like this; media players offering gapless playback and/or cross-fade aren’t), then, you’ll end up having to set the equalizer again (by quickly dis-, and, then, enabling the checkbox). Look for my forthcoming Multimedia Bible (yes, I’ve started working on it!!!), where I also list all the multimedia apps that, in this respect, work flawlessly.
Related threads: 1, 2, 3.

[APP][2.1+] Speed recorder

Hi. This time I share with you Speed recorder.
Just take a look what it can do
Description
With Speed ​​recorder you can record your current movement speed.
The route is stored and you can later play back the entire route from any point.
After the tour you will have access to such data as:
Maximum speed
Average speed
Travel time
distance
the coordinates of the initial and final point
With the recorder you can enable speed video recording, as professional automotive recorders (dvr).
You can turn video from any point.
You'll always have proof that you did not caused any collision.
You can set any type of the speed and distance, ie:
km/h, mph, kt
km, mi, ft
The application supports two languages​​:
English
Polish
Download
Speed recorder
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Hi!
i am a little irritated that there are no posts yet to this app, it seems quite useful to me...
In order to make it more "compatible" to the average drivers usage profile, it would be very handy to have it run in background fully, so video and data is recorded while other apps like e.g Navigation can run in the foreground.
Do you believe that is possible at all? Have it access GPS sensor data while another app is using GPS too? Have it record video in background?
I reckon that would make it an invaluable app.
I have very often had situations where i wanted to prove that i did not exceed a certain speed and could not prove it but needed to rely on the video recordings of the police who pulled me over. To get out of these awkward situations i always need to call my lawyer and make him find some stupid mistakes the police did in order to invalidate their measurements. This is a very tiresome process and could be much easier with recognized proofing. Like with an App that records video and data, displays the data in the video as overlay when played back and also has the statistical data merged into the video in order to have an avi file at the end which contains everything and is playable on all sorts of players.
I am not sure what processes you would have to go through to make this app recognized so it would serve as a valid evidence when one would have to take it to court. I am sure it would need some sort of governmental certification, but even without that, it is a good thing to have.
Thanks for your work!
regards,
Sneaky

[APP] [FREE] [2.3+] Anti Mosquito Lite

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Download From Google PlayStore : : https://play.google.com/store/apps/details?id=com.genyapps.AntiMosquitoLite
High frequency Sounds which are beyond the hearing sense of human ears.
Based on the characteristics of the mosquito, they fear the high frequency sounds like the sound of bats, dragonflies, who keep animals away mosquitoes, because it was feared enemies of mosquitoes. Anti Mosquito using external speakers emit high frequency sounds-from 17 KHz to 22 KHz, is the region that must mosquitoes.
This app prevents mosquitoes from biting you by emitting high frequency ultrasound from your phone that repels them away from the source of the sound.
Due to the characteristics of each different species of mosquitoes, mosquitoes develop software on the phone, we are helping users can adjust the frequency. You try to see if the frequency of other mosquitoes in your home must be removed. We recommend using frequencies from 20 kHz to 22 kHz, this frequency the human ear can not hear, but still effective in mosquito perfect.
This Mosquito repellent prevents you from getting bitten by mosquitoes and some other nasty bugs.
The application emit a very unique high frequency sound (ultra sound) that the insects dislike. The pitch of the sound is so high that most humans will not notice anything.
Download the freeAnti Mosquito Lite prank for Android and simulate a fight against biting mosquitoes. You can prank your fiends by telling them, the app generates a high frequency signal in the ultrasound range and scared off those pesky bloodsuckers. Only you know, it is just a simulation and not a real sonic sound.
How it works ?
- When you start the Anti Mosquito pro prank it produces high frequency sound which irritates the mosquitoes and helps you keep them away from you. You can adjust the volume of these sounds and keep it low so that it does not disturbs you.
- There are 6 high frequency sounds 8khz, 10khz, 12khz, 14khz, 15khz, 16khz. You can adjust the sound as you require.
- There are two quick setting button on top corner of the screen. One is for screen brightness. Clicking on it will reduce the screen brightness so that your mobile does not consume battery. Second one is for locking your mobile screen. you can lock your screen and yet the Anti Mosquito Lite prank will be on. It will use very less battery.
The main features of the application:
- Non-toxic to humans, pets in your family.
- Do not noisy.
- Anti perfect mosquito, the frequency can be adjusted accordingly.
- Applications can run in parallel with other applications, the notification bar, you can still use your phone normally with other functions.
- Anti mosquito single, easy to use.
- It does not take batteries, energy-saving batteries run it - you can turn off the display and can run Anti Mosquito Lite prank any term other application
- Mosquito Software on the phone and still free, then.
what the...reallly?

[APP][4.4+][FREE] Groove Pads - Make Beats and Mix Music

Make your own amazing music track! Take advantage of the great library of high quality sounds in different genres of music. Make beats, mix music and use studio quality effects. Record your performance or compose song from scratch!
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*
KEY FEATURES
- 24 colorful pads,
- make music by tapping pads,
- use step sequencer to create unique beats,
- 16 patterns for each of the pads with 16, 32 or 64 steps length,
- high quality sound packs,
- studio quality effects:
• reverb,
• flanger,
• phaser,
• low pass filter,
• band pass filter,
• high pass filter,
• bitcrusher,
• and more soon...
- control effects by touching XY pad,
- freeze XY parameters by 'hold' function,
- 24 channel mixer: volume, panning, mute and solo for each of the pads,
- reset mute or solo for all of the channels,
- record your music track,
- save and load your work at any time,
- song mode - create your own unique song by drag and drop patterns,
- favorite features at your fingertips - press and hold function button to change its mode,
- high performance audio engine,
- absolutely FREE.
Google Play: https://play.google.com/store/apps/details?id=com.fspdev.groovepads
Visit our website:* http://fspdevs.com
Like us on facebook:*https://www.facebook.com/GroovePads-272898706530578/
Your thoughts, feedback and suggestions help us make our app the best it can be! Write us:
[email protected]
Crashes on open, pixel Oreo 8.0. do you need logs? Or not support Oreo yet?
tiboric said:
Crashes on open, pixel Oreo 8.0. do you need logs? Or not support Oreo yet?
Click to expand...
Click to collapse
We will be grateful for logs from crash. Our email: [email protected]
Feedback
We are counting on your feedback This thread is also a place to request features. We will do our best to release it as soon as possible
Groove Pads 0.7.6 released. Android oreo issue and many others fixed!

[App] [4.0+] Frequency Generator

Hello,
I create that thread to present you Frequency Generator, a simple tool to generate free tones between 1Hz and 24000Hz for a duration of your choice. Frequency Generator is available on the Google Play Store in two versions :
- Free supported by Ads : https://play.google.com/store/apps/details?id=com.ssaurel.frequencygenerator
- Paid without Ads : https://play.google.com/store/apps/details?id=com.ssaurel.frequencygenerator.pro
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You can discover Frequency Generator in action on YouTube :
Use the slider to select the frequency of your choice, then use the second slider to select the duration of the tone you want to generate and finally you have just to click on the play button to play the tone which is a sine wave signal.
Frequency Generator is a simple and efficient tool covering the following use cases :
- Testing speakers or audio devices
- Make a quick test of your Hearing by determining the range of frequencies you are able to hear. For this use case, a more complete solution can be found with Hearing Test : https://play.google.com/store/apps/details?id=com.ssaurel.hearingtest
- Experiencing the acoustic beat phenomenon. What is the acoustic beat phenomenon ? The beat phenomenon is an interference pattern between two sounds of slightly different frequencies, perceived as a periodic variation in volume whose rate is the difference of the two frequencies. To experience this phenomenon, you have just to launch Frequency Generator on two devices and then generate a frequency of 560Hz on the first and 563Hz on the second. Like that, you will hear an acoustic beat of frequency 3Hz. Musicians commonly use interference beats to objectively check tuning at the unison, perfect fifth, or other simple harmonic intervals.
- Make some jokes to your friends or in the public transports
Some screenshots :
* Use the slider to select frequency and duration
* Generate your free tone by clicking on the play button
You can also download Frequency Generator directly on the SSaurel's Server : https://www.ssaurel.com/frequencygenerator/FrequencyGenerator.apk
Don't hesitate send me your feedback or give me your ideas to improve Frequency Generator in comments.
Thanks.
Sylvain

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