Visitors of our stand at last September's IBC will have already spotted it.
The remaining work took a bit longer than expected, and we're still far from completely done, but the public beta is here:
PhoneBooster
In short: it takes the voice of a caller, and regenerates the missing frequencies from scratch, resulting in a much less tinny and more natural sound, closer to the original voice.
To achieve that, it uses Artificial Intelligence. A computer has been working day and night, trying to figure out how human voices sound and what to make of it when it only hears the part that gets through a phone line.
Samples
These samples were made with settings that allow for a lot of regeneration.
If the effect is perceived as too noisy and/or too shrill, PhoneBooster can be easily turned down.
Real world samples
"Radio fragment 1" -
Telephone recording -
Repaired audio
"Radio fragment 2" -
Telephone recording -
Repaired audio
Synthetic samples
Sample 1 -
Telephone recording -
Repaired audio
Sample 2 -
Telephone recording -
Repaired audio
Sample 3 -
Telephone recording -
Repaired audio
Sample 4 -
Telephone recording -
Repaired audio
Operating mode
In an ideal situation, an instance of PhoneBooster has direct access to the incoming signal of a single telephone line.
It can run on the hardware that receives such inputs, or on a separate device.
PhoneBooster 'repairs' the telephone sound, and feeds the result into an audio processor (preferably StereoTool

).
Apart from the resulting voice sounding (subjectively) better, the audio processor will have a much broader and more consistent input signal to work with.
PhoneBooster will also be built into StereoTool. There it can either run on a separate input, or on a premixed signal.
The latter will require protection against affecting non-telephone content, which will also be built-in.
Latency
Depending on it's quality setting and the strength of the system it runs on, PhoneBooster will introduce 25 to 100ms of delay.
While this is low, considering a telephone connection already introduces more delay than that, we're still working on lowering this.
Licencing
PhoneBooster will require an internet connection to activate, but can operate off-line after that.
Licences will be bound to the device it is installed on, and will be invalid for any other device after activation.
We are still undecided on the pricing.
The beta version cannot be licenced yet, and will introduce beeps.
Download the beta
Please take into account that PhoneBooster is still in development, and the Beta has some known issues:
- The algorithms are still computationally quite heavy
- The non-telephone content protection (for when PhoneBooster is run on a mixed input signal of e.g. a telephone line, a DJ's microphone and a source of music) is not yet perfect
- It is impossible to perfectly recreate the original voice, but we're still getting closer each day
- Licencing the product to remove beeps is not yet possible
Windows stand-alone download (NOT AN INSTALLER - this will run directly when you start it)