#Audio driver for rp1000 osx software

For example, the 16-bit integer samples in standard CD audio allow 65,536 possible values between silence and maximum level. In linear PCM audio, a sample value varies linearly with the amplitude of the original signal that it represents. A packet defines the smallest meaningful set of frames for a given audio data format. In compressed formats, it is typically more. In linear PCM audio, a packet is always a single frame. For instance, a stereo sound file has two samples per frame, one for the left channel and one for the right channel.Ī packet is a collection of one or more contiguous frames. Standard compact disc (CD) audio uses a sampling rate of 44.1 kHz, with a 16-bit integer describing each sample-constituting the resolution or bit depth.Ī sample is single numerical value for a single channel.Ī frame is a collection of time-coincident samples. Digital audio recording creates PCM data by measuring an analog (real world) audio signal’s magnitude at regular intervals (the sampling rate) and converting each sample to a numerical value. Most Core Audio services use and manipulate audio in linear pulse-code-modulated ( linear PCM) format, the most common uncompressed digital audio data format. Figure 1-2 iOS Core Audio architecture A Little About Digital Audio and Linear PCM Figure 1-2 provides a high-level view of the audio architecture in iOS. For example, Audio Session Services lets you manage the audio behavior of your application in the context of a device that functions as a mobile telephone and an iPod. However, there are additional services in iOS not present in OS X. There is no API for services that must be managed very tightly by the operating system-specifically, the HAL and the I/O Kit. Use System Sound Services (represented in the figure as “System sounds”) to play system sounds and user-interface sound effects.Ĭore Audio in iOS is optimized for the computing resources available in a battery-powered mobile platform. Use Core Audio Clock Services for audio and MIDI synchronization and time format management.

Use Music Sequencing Services to play MIDI-based control and music data. In OS X you can also create custom audio units to use in your application or to provide for use in other applications. Use Audio Unit Services and Audio Processing Graph Services (represented in the figure as “Audio units”) to host audio units (audio plug-ins) in your application. In OS X you can also create custom codecs. Use Audio File, Converter, and Codec Services to read and write from disk and to perform audio data format transformations. Use Audio Queue Services to record, play back, pause, loop, and synchronize audio. You find Core Audio application-level services in the Audio Toolbox and Audio Unit frameworks. The Core MIDI (Musical Instrument Digital Interface) framework provides similar interfaces for working with MIDI data and devices. You can access the HAL using Audio Hardware Services in the Core Audio framework when you require real-time audio. Audio signals pass to and from hardware through the HAL. In OS X, the majority of Core Audio services are layered on top of the Hardware Abstraction Layer (HAL) as shown in Figure 1-1. Core Audio in iOS and OS XĬore Audio is tightly integrated into iOS and OS X for high performance and low latency. Read this chapter to learn what you can do with Core Audio.

#Audio driver for rp1000 osx software

It includes a set of software frameworks designed to handle the audio needs in your applications. Audio recorded via USB in the RP1000 is always tapped off of the audio feeding the XLR outputs.Core Audio is the digital audio infrastructure of iOS and OS X. Turn Knob 5 to adjust the USB Record Level.Ĭhanges made to the USB parameters are saved automatically and will affect the global performance of the RP1000 and all of its presets.Turn Knob 4 to adjust the USB Playback Mix.From the preset name display, press the Edit Down button once to enter Edit mode.To change the USB Setup options, follow these steps: The range for this control is from USB Mix 0% (all that is heard is the RP1000 processing, no playback) to USB = RP (both USB playback 36 and RP1000 have equal levels) to RP Mix 0% (all that is heard is the USB playback in the outputs, no RP1000 processing). USB Playback Mix – This option controls the playback mix between RP1000 processing and USB playback from your computer’s recording application.USB Record Level – This option provides a digital level control for boosting or cutting the level sent to your recording application.