ASIO Source Filter Specification

The ASIO source filter can only be used as the first filter of an input graph. It reads audio data from the specified ASIO device.

JSON Structure

JS

{
	"name": "ASIO Source",
	"device": {
		"name": "...",
		"channels": "..."
	},
	"format": {
		"sampleRate": ...,
		"resolution": ...
	}
    "allowDifferentSampleRate": true/false,
    "lawoR3layName": "..."
}

Field	Description
device	Defines the ASIO device and channels to use. name: Name of the device as defined by the device's driver. It is sufficient to specify only a part of this string in the name field, as long as it is unique to the device. channels: A comma-separated list of channel numbers (0-based). E.g., "0,1,3" will record three channels, using the 1st, 2nd and 4th input channels of the device.
format	Describes the audio format, which is to be read from the device. sampleRate: Sampling rate in Hz. The supported values depend on the device. Most devices support at least 44100 and 48000 Hz. A value of 0 means, that the sample rate is automatically selected. resolution: Bit width of a single audio sample. The supported values depend on the device. Most devices support 16 and 24 bit audio.
allowDifferentSampleRate	The parameter is optional, the default is `false` . If set to `true` , the filter will automatically select a different sample rate, if the sample rate specified in "format" is not available. That can be the case, if the rate is not supported at all by the hardware or while the hardware is actively running with a different rate.
lawoR3layName	The parameter is optional, the default is empty. It is only relevant, if the device is a LAWO R3LAY virtual sound card. If the value is non-empty, the given name will be passed to the R3LAY as the "name" of this ROAD instance. Note: If this parameter is not used, but the ROAD job has an alias name, this alias is passed to the R3LAY device as the instance's "name".

Notes

The "name" of a given ASIO device is not always obvious. ROAD's devices API to enumerate the names of all installed ASIO devices, as well as the number of channels they offer.
There is no need to specify a channel count in the "format" data, because this is implicitly defined by the number of entries in the "channels" list of the device specification.
When auto-selecting a sample rate, because "sampleRate" is 0 and/or "allowDifferentSampleRate" is true , the filter tries the following values: 96000 Hz, 48000 Hz, 44100 Hz, and the current value reported by the ASIO driver.
Configure the ASIO device in its Control Panel for 32 bits per sample. Since ROAD version 1.12.602.0, the ASIO Source filter also supports devices delivering 24-bit and 16-bit samples.