ISA 828 User Guide Mode d’emploi FA0145-04
WARNINGS & CAUTIONS THE APPARATUS SHALL NOT BE EXPOSED TO DRIPPING OR SPLASHING, AND NO OBJECTS FILLED WITH LIQUIDS, SUCH AS VASES, SHALL BE PLACED ON THE APPARATUS VENTILATION SHALL NOT BE IMPEDED BY COVERING THE VENTILATION OPENINGS WITH ITEMS, SUCH AS NEWSPAPERS, CLOTHS, CURTAINS ETC. NO NAKED FLAME SOURCES, SUCH AS LIGHTED CANDLES, SHOULD BE PLACED ON THE APPARATUS MAINS LEAD - THIS EQUIPMENT MUST BE EARTHED AND FITTED WITH THE CORRECT LEAD FOR THE COUNTRY OF OPERATION.
Contents Getting Started and Powering Up . . . . . . 4 Front Panel . . . . . . . . . . . . . . . . . . . . . . . . 5 Rear Panel . . . . . . . . . . . . . . . . . . . . . . . . . 8 Digital Options . . . . . . . . . . . . . . . . . . . . . 10 Applications . . . . . . . . . . . . . . . . . . . . . . . 12 FAQs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Specifications . . . . . . . . . . . . . . . . . . . . . 18 Warranty . . . . . . . . . . . . . . . . . . . . . . . . . 19 Mode d’emploi . . . .
Getting Started and Powering Up The ISA 828 is a high quality eight-channel microphone preamplifier, which can be used to record microphone, line-level or instrument sources. Microphones and line-level sources for all eight inputs are connected on the rear panel, whilst instruments are plugged directly into the front panel (inputs 1-4 only). The front panel also features level controls and other settings such as phantom power and impedance for each of the eight analogue inputs.
Front Panel Switch Input metering to pre ADC (when using Inserts for external processing of Inputs) Instrument Inputs (Inputs 1-4) Power switch Controls for Inputs 1-8 Digital Options (for optional card) Input Stage Activates a gain range of 30-60 across the Gain (stepped) dial (the default is 0-30) Phantom Power switch Meter in dBFS Selects input impedance to 600, 1k4, 2k4 or 6k8 Ohms Selects type of input Eight numbered sections are included on the front panel for setting up each of the eight anal
Mode 1 Mic Gain Range 0-30 With the 30-60 switch off, the stepped gain dial operates over a gain range of 0dB to +30dB, the level of gain chosen being indicated on the front panel by the outer arc of yellow numbers around the gain knob. Mode 2 Mic Gain Range 30-60 With the 30-60 switch on (illuminated), the stepped gain dial operates over a gain range of 30dB to 60dB, the level of gain chosen being indicated on the front panel by the outer arc of yellow numbers around the gain knob.
Insert In Activating the INSERT switch (illuminated when active) breaks the signal path of the channel, so that the signal connected to the ADC Input 25-pin connector on the rear panel routes to the digital output card (if connected) rather than the direct mic, line or instrument signal. Note that the mic, line or instrument signal will still route to the analogue output on the rear panel with this switch active.
Mode 2. Meters Pre ADC switch engaged This is the mode to use when the analogue input signals are being routed to other hardware devices (such as dynamics processors) using the analogue outputs/ADC Input on the rear panel (acting as sends/returns) before converting to digital. Obviously, the optional digital output card should be installed if wanting to use this mode. Meters 1 to 8 indicate the peak level of channels 1-8 received at the ADC Input.
Analogue Inputs On the rear panel, there are 8 XLR inputs for connecting microphones and 8 1/4” TRS inputs for line-level sources. Each one is numbered accordingly and corresponds to the relevant section on the front panel.
IEC mains inlet This socket allows the supplied IEC cable to be connected to enable the 828 to be powered. A fused voltage selector is also present, with a diagram alongside to indicate the positions that relate to each voltage. Optional digital card connections The remaining connections (if present) are those on the optional digital card and are explained fully in the next section. Digital Options The optional ADC can be retrofitted to a standard ISA 828 at any time.
In single-wire mode, switch out, the AES channels 1-8 can be transmitted at sample rates up to 192kHz using only 8 AES connections. Therefore, channels 1-8 are always available in AES format, regardless of the S/PDIF switch setting. ADC Card DB25 Pin Out Configurations Pin No. Jumpers disabled (default) ProTools™ Compatible 44.1 - 96kHz Jumpers disabled Jumpers enabled Single ProTools™ Compatible Wire Mode 44.1 - 192kHz Dual Wire Mode 88.
176.4/192kHz sample rates: Connector 1 = channels 1 and 2 Connector 2 = channels 3 and 4 ADAT™ lightpipe cables are available from your local dealer, or in the UK from Studiospares (tel +44 (0)20 74821692): stock number 585-510. Word Clock In and Out The internal ADC can be synchronised to an external word clock. By pressing the front panel Ext switch, the synchronisation mode can be switched between standard external word clock and 256x external word clock.
Level Professional microphones tend to have low output impedances and so more level can be achieved by selecting the higher impedance positions of the ISA 828 mic pre-amp. Frequency response Microphones with defined presence peaks and tailored frequency responses can be further enhanced by choosing lower impedance settings.
Impedance Setting Quick Guide In general, the following selections will yield these results: High mic pre-amp impedance settings · Will generate more overall level · Will tend to make the low- and mid-frequency response of the microphone flatter · Will improve the high-frequency response of the microphone.
Recording with Inserts Focusrite Compounders (Stereo Compression) x 4 Analogue I/Ps Analogue O/Ps ISA 828 has all eight Insert switches engaged x8 Digital Storage Medium Recording from AES Outputs 1-8 to Pro Tools HD™ at 192kHz Pro Tools HD™ 192 Interface AES/EBU 25-pin Inputs (requires 2 cards) Word Clock Output (1x or 256x) Cable pinout according to Appendix 1 ISA 828 Digital Card in 2-wire mode (Jumpers in default ‘enabled’ position) 15
FAQs Q: What are the basic features of the ISA 828? A: Eight Focusrite mic pres, eight line inputs, four instrument inputs, optional 8-channel 192kHz A/D conversion. Q: Which applications is the ISA 828 suitable for? A: The ISA 828 can be used as a multi-channel high quality front end for Digital Audio Workstations, allowing multichannel recording to HD. Equally, it can be used simply as the perfect interface or A/D converter for synths/other linelevel devices.
Q: What rear panel connections are featured? A: The ISA 828 has 8 XLRs for connecting microphones and 8 1/4” TRS Jack line-level inputs. There are also 2 25-pin D-type connectors: one for the analogue outputs and another for sending an external signal to the optional ADC (most likely if using the Insert switches on the front panel and returning the mic/line/inst signals from additional processing for digital conversion).
Specifications Mic Input Response • Gain range = 0dB to 60dB in 10dB steps • Input Impedance, variable as follows:Switched Impedance setting Equivalent Input Impedance at 1kHz Low 600 ISA 110 1400 Med (Medium) 2400 High 6800 • EIN (equivalent input noise) = -126dB measured at 60dB of gain with 150 Ohm terminating impedance and 22Hz/22kHz bandpass filter • Noise at main output with gain at unity (0dB) = -97dBu measured with a 22Hz/22kHz bandpass filter • Signal to noise ratio relative to max headro
Warranty All Focusrite products are covered by a warranty against manufacturing defects in material or craftsmanship for a period of one year from the date of purchase. Focusrite in the UK, or its authorised distributors worldwide, will do their best to ensure that any fault is remedied as quickly as possible. This warranty is in addition to your statutory rights. This warranty does not cover any of the following: • Carriage to and from the dealer or factory for inspection or repair.
Appendix 1 Recording AES Outputs 1-8 to Pro Tools ™ HD at 192kHz To record all eight channels digitally to Pro Tools™ HD at 192kHz, all eight AES channels need to be enabled on the ISA 828 (default jumper positions shown on Appendix 2) and 2 Digital cards must be fitted in the HD192 interface. A 25-pin to two 25-pin cable must then be used, with the following pinout: Pin No.
Appendix 2 Digital Card Jumper Positions - Disabling AES Outputs 5-8 Four jumpers on the digital card can be made to disable channels 5-8 on the AES Output. This is so that a standard 25-pin to 25-pin Pro Tools™ cable can be used to record channels 1-4 at 192kHz. (Half of the connections on the Digidesign Digital Input are used for receiving and the other half for transmitting.) For more information, consult the relevant section of the Pro Tools™ User Guide.
