## 8.2.1 Connection of Multiface to a PC

Each 24bit/96kHz multiple-channel A/D device made by RME consists of three devices.

• RME HDSP I/O box: The RME HDSP Multiface Avena unit,

• RME HDSP interface: Either an RME HDSP PCI card or an RME HDSP CardBus card
Operation of these cards has not been confirmed, and are therefore outside the scope of our support.

• Preamplifier for microphone: RME OctaMic-II RME OctaMic and Yamaha HA -8 have been used, although both models have been discontinued.

However, a preamplifier for microphones is not necessarily needed. If the recording level is good, it will not be necessary to connect the device to a preamplifier. Connect these hardware devices to a PC by referring to the attached manual.

### 8.2.1.1 Installation and setting of software for Multiface

To enable Linux to recognize Multiface as a multichannel A/D device, it is necessary to install a general-purpose driver for ALSA devices, to install firmware and software for Multiface and to set their parameters. Users are strongly recommended to install these devices as described by their manufacturers. Although compiling and installing from the source can be performed, it may cause conflicts with other software. This may result in the failure of recording/replaying during actual operations even if compiling and installing seemed to be completed successfully. Note that conflicts with pulseAudio often occur. Detailed descriptions strongly depend on individual system environments and they are therefore omitted here. Rather, this chapter describes the method of installing a general-purpose driver for ALSA devices, followed by installation work to enable the hdsp command. This is required for the initialization of Multiface followed by settings of the hdsp command. Finally, an example of the recording network with HARK is described.

### 8.2.1.2 Installation of a general-purpose driver for ALSA devices

General-purpose drivers (alsa-lib, alsa-driver) for ALSA devices are often already installed. Input the following bold-faced parts to confirm that they have been installed. $>$ indicates a command prompt. If the italic part message is displayed, alsa-lib and alsa-drive are already installed and therefore it is not necessary to install them. Since version numbers differ depending on usage environments, different version numbers may be displayed during actual operations. In this test environment, use version 1.0.24.

> cat /proc/asound/version
Advanced Linux Sound Architecture Drive Version 1. 0. 24.


If they are not installed, they will be installed automatically by the following operation. Therefore proceed to the next operation in the chapter.

### 8.2.1.3 Installation to enable command required for the initialization of Multiface

Two packages are required.

• alsa-tools-gui

To install these packages, use either of the items below.

• Synaptic package manager

• apt-get

Installing these packages enable three commands required for setting Multiface.

• hdspconf (Package : alsa-tools-gui)

• hdspmixer (Package : alsa-tools-gui)

An example of an installation with apt-get is shown below.

> sudo apt-get update
> sudo apt-get install alsa-firmware-loaders
> sudo apt-get install alsa-tools-gui


> bunzip2 -d alsa-firmware-1.0.24.tar.bz2
> tar vfx alsa-firmware-1.0.24.tar
alsa-firmware-1.0.24/
alsa-firmware-1.0.24/multisound/
(skipped)
config．status: creating aica/Makefile
config．status: executing depfiles commands
> make
> sudo mkdir -p /lib/firmware/hdsploader


The hdsp command is installed during the above operation, enabling the setting and operation of Multiface.

### 8.2.1.4 Setting hdsp commands

The necessary three hdsp commands are hdsploader, hdspconf and hdspmixer.

hdsploader is a command to upload the firmware program (multiface_firmware_rev11.dat) to initialize the FPGA of Multiface. An execution example is shown below. Although the error message (Hwdep ioctl error on card hw: 0 : Device or resource busy.) is displayed, it should be ignored, since it is not a problem here. This error message is displayed when executing more than twice on the same system. This error message is always indicated during this operation in a system is executed during the start-up of OS.

# hdsploader
hdsploader - firmware loader for RME Hammerfall DSP cards
Looking for HDSP + Multiface or Digiface cards :
Card 0 : RME Hammerfall DSP + Digiface at 0xf9df0000, irq 16
Upload firmware for card hw:0
Hwdep ioctl error on card hw:0 : Device or resource busy.
Card 1 : HDA Intel at 0xfdffc000 irq 30

• hdspconf
A setting window of Multiface opens when executing hdspconf,with the sampling frequency set in this window. For other items, refer to the documents for Multiface. Figure 8.4 shows an example of a setting in this window. The settable sampling rates are 32kHz, 44.1kHz, 48kHz, 64kHz, 88.2kHz and 96kHz. In this example, 32kHz was selected.

• hdspmixer
GUI of the mixer is displayed when executing hdspmixer. Input and output levels can be controlled and confirmed. Figure 8.5 shows an example of the mixer.