AF bit - User manual

Index

1. PRODUCT DESCRIPTION AND PRECAUTIONS

2. PACKAGE CONTENT

2.1 AF M1.7 bit
2.2 AF C4.10 bit
2.3 AF M5.11 bit
2.4 AF C8.14 bit
2.5 AF M8.14 bit
2.6 AF M12.14 bit

3. INSTALLATION AND DIMENSIONS

3.1 AF M1.7 bit
3.2 AF C4.10 bit
3.3 AF M5.11 bit
3.4 AF C8.14 bit
3.5 AF M8.14 bit
3.6 AF M12.14 bit
3.7 DRC AC, DRC MP CAN INSTALLATTION AND CONNETTORS

4. WIRED CONNECTIONS

4.1 CABLE SIZE CALCULATION TABLE
4.2 DESCRIPTION OF CONNECTION PANEL

REQUIRED CONNECTIONS

POWER AND GROUND
CTRL (REM IN-OUT / CONTROLS)
SPEAKER OUTPUT

◼︎ HOW TO MAKE BRIDGE CONNECTION

◼︎ AF M1.7 bit
◼︎ AF C4.10 bit
◼︎ AF M5.11 bit
◼︎ AF C8.14 bit
◼︎ AF M8.14 bit
◼︎ AF M12.14 bit

SPEAKER IN
PRE IN
USB PORT
ART SWITCH
FUSE
LOGO - STATUS INDICATOR

OPTIONAL CONNECTIONS

DRCC
OPTICAL IN
DSP OUT
MAESTRO
ADC
INPUT EXPANSION SLOT

5. HOW TO TURN ON THE AMPLIFIER

    5.1 PROGRAMMABLE TURN ON/OFF DELAYS
6. FIRMWARE UPGRADE
7. RESCUE PROCEDURE
8. BIT DRIVE SOFTWARE – HOW TO TUNE YOUR AF BIT.

9. FAQ – FREQUENTLY ASKED QUESTIONS

 

1. PRODUCT DESCRIPTION AND PRECAUTIONS

IMPORTANT: Before connecting the amplifier, read this manual carefully.
Incorrect connections may damage the amplifier or the speakers in your car audio system!

PRODUCT DESCRIPTION

The AF bit is a multichannel amplifier equipped with a bit DSP processor. It is designed for use in 12V+ electrical systems in automobiles. All amplified output channels, as well as additional non-amplified output channels, are individually processed by the integrated Audison bit processing section.

The Audison bit DSP processor includes an advanced set of electrical signal tools to correct the signal from the source unit, and a powerful set of acoustic tools to optimize the sound in the vehicle cabin.

All AF bit amplifiers have eight analog input channels and a Toslink SPDIF digital input. Each of these is managed using the Audison bit Drive software tool for PC, which can be downloaded at https://www.audison.eu/support/software-and-firmware/

bit Drive software manual is available at the following link bit Drive - User manual

For best results, it is recommended to have calibration and adjustment performed by an Audison dealer. Audison dealers have access to various technical documents that guide them in using the different features of the bit Drive software.

MINIMUM REQUIREMENTS

To install the bit Drive software and configure the product:

• A PC running Windows 10 or Windows 11.
• Processor with a minimum speed of 1.5 GHz
• Minimum 2 GB RAM
• Graphics card with a minimum resolution of 1024 x 768 pixels
• At least 512 MB of free hard drive space is required.

DETAILED DESCRIPTION

The AF bit amplifier has 8 analog input channels. Each input channel can be used with its balanced RCA PRE-IN (low level) or via the attenuated balanced SPEAKER IN (high level).

NOTE: An input channel cannot simultaneously use both the preamp input and the speaker-level input.

The bit processor also includes a set of input signal correction tools that allow reversing the processing applied to the incoming signal. This can be critical for achieving good sound when using OEM source units.

The AF bit also features a Toslink SPDIF input.

Each AF bit also includes an expansion slot where you can insert an optional F4IN or F2O expansion card to increase the number of inputs.

The AF bit can interface with nearly all OEM systems, even those with integrated DSP processing. In addition to automatic de-EQ and de-Time correction, the bit Drive software offers expert-level controls for signal correction, including direct phase manipulation via all-pass filters.

Each input channel features either preamp or speaker-level inputs

• Preamp inputs are balanced differential for maximum noise suppression
• Speaker-level inputs are attenuated and feature universal speaker load simulation
• Adjustable input sensitivity with overload indication
• Adjustable 12-band parametric equalizer per channel – each input EQ band can be configured as peak, low-shelf, high-shelf, notch, or all-pass
• Digital control of time delays. The electrical RTA helps configure these input controls

Each output channel features:

• A fully featured 15-band parametric equalizer – each output EQ can be configured as peak, low-shelf, high-shelf, notch, or all-pass
• Adjustable electronic crossover in 1 Hz steps, with Butterworth / Linkwitz / Bessel / Chebyshev / QLP filters, and slopes from 6 to 48 dB
• Time delay (can be entered directly or calculated based on path length differences)
• Output level and polarity control
• Output overload indicators

In addition, the five parametric bands of the Final Equalizer affect all output channels simultaneously, allowing the user to adjust the sound of the entire system without affecting the balance between channels.

The built-in acoustic RTA function helps the user set up output adjustments (requires a USB measurement microphone).

The Tune routine can perform automatic calibration of time delays, levels, and output EQ using the USB microphone.

OPTIONAL ACCESSORIES

• DRC AC: Allows control of master volume, subwoofer volume, source selection, preset memory selection, and final tuning EQ activation/deactivation. DRC AC functionality is configured in the bit Drive software
• DRC MP CAN: Controller with OLED display, capable of managing master volume, subwoofer volume, source selection, preset memory selection, final tuning EQ activation/deactivation, fader/balance settings, and many other functions. This product does not require programming in the bit Drive software. For more details, refer to the DRC MP CAN user manual.
• F4IN: This expansion card adds 4 additional speaker-level input channels to the AF bit. These feature higher voltage handling than the native AF bit amplifier inputs and are suitable for high-voltage bass channels in high-end OEM systems.
• F2O: This expansion card adds a second Toslink SPDIF optical input and also includes an SPDIF coaxial input for digital signals.
• B-CON: This Hi-Res Bluetooth receiver enables direct digital input from your compatible Bluetooth device and high-resolution audio from LDAC-compatible devices. For maximum dynamic range, Audison Absolute Volume can be used to let the phone control the AF bit amplifier output. Refer to the B-CON user manual for more information.
• Maestro AR: The native Maestro port ensures interfacing with devices equipped with the Maestro / ADC protocol. This allows factory audio settings to act directly on the AF amplifier, providing a correct and clean signal from the OEM system.
• AF LINK: This wiring connects the DSP OUT preamp outputs of the AF bit to external AF D amplifiers.

2. PACKAGE CONTENT

2.1 AF M1.7 bit

 

2.2 AF C4.10 bit

2.3 AF M5.11 bit

 

2.4 AF C8.14 bit

 

2.5 AF M8.14 bit

 

2.6 AF M12.14 bit

Note: The test track CD is not included. Please download the test tracks to a USB flash drive.
Here is the link to the Audison test tracks download page:

https://www.audison.eu/support/test-tracks/

3. INSTALLATION AND DIMENSIONS

After completing all wiring connections to the appropriate connectors, insert them into the amplifier as shown.

⚠️WARNING: PROPER INSTALLATION OF THIS AMPLIFIER IS CRUCIAL TO AVOID UNINTENTIONAL DAMAGE TO THE VEHICLE.
Before modifying the vehicle in any way, including the use of the supplied screws, ensure that vehicle functionality is not affected. Installation by an authorized Audison dealer is recommended.

⚠️WARNING: It is strongly recommended to avoid leaving the USB cable connected to the product, as its ground terminal could accidentally create a shortcircuit with the +12V supply terminal of the AF bit. If you choose to keep the USB cable connected, it is recommended to use a USB cable with isolated protection cover”

3.1 AF M1.7 bit

3.2 AF C4.10 bit

3.3 AF M5.11 bit

 

3.4 AF C8.14 bit

3.5 AF M8.14 bit

3.6 AF M12.14 bit

 

3.7 INSTALLATION OF DRC AC, DRC MP CAN, AND CONNECTORS

Note: please, remind that DRC AC and DRC MP CAN share exactly the same connector and cable

4. WIRED CONNECTIONS

4.1 CABLE SIZE CALCULATION TABLE

⚠️WARNING: IT IS ESSENTIAL TO INSTALL THIS AMPLIFIER SAFELY TO AVOID DAMAGE TO THE VEHICLE. INCORRECT POWER WIRING MAY CAUSE DAMAGE TO THE VEHICLE, INCLUDING FIRE. FOLLOW THE CORRECT WIRING PROCEDURES. INSTALLATION BY AN AUTHORIZED AUDISON DEALER IS RECOMMENDED.

4.2 DESCRIPTION OF CONNECTION PANEL

Legenda

	REQUIRED CONNECTIONS
	OPTIONAL CONNECTIONS

REQUIRED CONNECTIONS

POWER AND GROUND

+ 12V Power (11-15 VDC): Terminal for connecting the 12V power cable. Route this cable directly to a fuse holder (not included) connected to the positive terminal of the vehicle’s battery. For optimal current transfer, it is recommended to use cables with the largest possible cross-section, matching the size of the cable connected to the negative pole, and to use the Ferrules provided in the package.

- Power (Ground): Terminal for connecting the amplifier’s negative power ground

NOTE: You must use a low-resistance ground connection to the battery for the amplifier to deliver its rated power. In some cases, this means grounding directly to the vehicle battery’s grounding point or improving the ground path from the connection point to the battery. Modern vehicles often have problematic ground return paths.

IMPORTANT: If the 12V+ power supply or ground path is insufficient, the Low Voltage Protection mute function may activate, resulting in no audio output.

To properly connect the ground (-), you can use an existing screw on the vehicle’s metal body. If necessary, remove any paint or grease residues.
Use a digital multimeter to ensure there is low resistance between the battery’s negative (-) terminal and the mounting point. If possible, connect all audio component grounds to the same grounding point. This helps reduce most of the interference that can occur in audio playback.

IMPORTANT: Observe the correct polarity of connections as indicated by the terminals! Incorrect connections may damage the amplifier.

After powering on, wait at least 10 seconds before turning on the AF bit.

MULTIPLE POWER CONNECTION

In the case of systems with more than one AF bit amplifier, please follow these recommendations for multiple power connections.

 

CTRL (REM IN-OUT / CONTROLS)

Terminals for AF bit Power On and Cascading Amplifiers:

- Remote IN (blue): Input for remote turn-on of the AF bit via the Remote Out from an audio source device. It is possible to connect the REM IN to the vehicle’s ignition switch terminal (ACC). The applied voltage must be between 7 and 14.5 VDC. If using a source with BTL-type amplified outputs, the AF bit can turn on automatically, so connecting the REM IN terminal is not necessary.

- Remote OUT (blue/black) : Output for remotely turning on other devices/amplifiers connected to the AF bit. After powering on, the product takes about 12 seconds to provide REM OUT at the output, but this delay can be configured via software. This output has a current capacity of 200 mA and can drive an automotive relay.

Software-Programmable Terminals for Various Functions:

- CONTROL 1 (brown)/ CONTROL 2 (pink): Terminals configurable via the bit Drive software to activate a command of your choice among source change, preset change, volume change, or enabling/disabling Final Tuning EQ. This command is activated by connecting the terminal to +12 V.
Please refer to paragraph 7.5 TRIGGER in Chapter 7 of the bit Drive software manual

 

SPEAKER OUT

Each AF bit is supplied with speaker output wiring corresponding to its output channels. These outputs can handle minimum loads of 2Ω.

IMPORTANT: Minimum load is 2Ω (4Ω when in bridged mode). Never allow the speaker output wires to short to the vehicle chassis or to another speaker wire!
This could trigger the mute protection function or, in extreme cases, cause equipment damage.

HOW TO MAKE BRIDGE CONNECTION

Each pair of SPEAKER OUT channels on the AF bit can be bridged to create a single, more powerful channel.
Bridged mode requires a minimum load of 4Ω.

IMPORTANT:

1. To bridge a stereo channel pair into a more powerful single channel, connect the positive (+) speaker wire of the odd-numbered channel to the positive (+) speaker terminal, and connect the negative (-) speaker wire of the even-numbered channel to the negative (-) speaker terminal.2. Do not attempt to bridge channels that do not belong to the same stereo pair.3. Incorrect wiring of outputs during bridging can damage the AF bit amplifier. Ensure unused wires do not short against each other or the chassis ground.

Example of Bridge Connection

Examples of SPK OUT connections:

AF M1.7 bit

Supplied with a 4-pin cable that allows connection of up to 2 amplified SPK OUT channels. The 2 amplified SPK OUT channels are internally connected in parallel to achieve a total power output of 600 W × 1 @ 4Ω.

There are several possible connection modes:

1.  
   1. One subwoofer connected to a single SPK OUT channel
   2. One subwoofer connected to both SPK OUT channels in parallel (to provide more current than the previous case)
   3. Two subwoofers connected to the two SPK OUT channels and driven in Mono mode

CH 1  AMPLIFIED OUTPUT CHANNELS CONFIGURATION

POWER CHANNEL CONFIG
STEREO MODE	BRIDGE MODE
CH1 600 W @ 4 Ω CH1 1000 W @ 2 Ω CH1 1200 W @ 1 Ω	-

AF C4.10 bit

Supplied with an 8-pin cable that allows connection of up to 4 amplified SPK OUT channels, delivering 90 W RMS × 4 @ 4Ω, connectable using the dedicated cable provided.

Example of Bridged Channel Connection

CH 1 ÷ CH 4 AMPLIFIED OUTPUT CHANNELS CONFIGURATION

POWER CHANNEL CONFIG
STEREO MODE	BRIDGE MODE
CH1 90 W @ 4 Ω / 150 W @ 2 Ω CH2 90 W @ 4 Ω / 150 W @ 2 Ω	CH1+ / CH2- 300 W @ 4 Ω
CH3 90 W @ 4 Ω / 150 W @ 2 Ω CH4 90 W @ 4 Ω / 150 W @ 2 Ω	CH3+ / CH4- 300 W @ 4 Ω

 

AF M5.11 bit

Supplied with an 8-pin cable that allows connection of up to 4 amplified SPK OUT channels delivering 100 W × 4 @ 4Ω, plus 1 amplified SUB OUT channel delivering 400 W × 1 @ 4Ω, connectable using the dedicated cable provided.

Example of Bridged Channel Connection

CH 1 ÷ CH 4 AMPLIFIED OUTPUT CHANNELS CONFIGURATION

POWER CHANNEL CONFIG
STEREO MODE	BRIDGE MODE
CH1 100 W @ 4 Ω / 150 W @ 2 Ω CH2 100 W @ 4 Ω / 150 W @ 2 Ω	CH1+ / CH2- 300 W @ 4 Ω
CH3 100 W @ 4 Ω / 150 W @ 2 Ω CH4 100 W @ 4 Ω / 150 W @ 2 Ω	CH3+ / CH4- 300 W @ 4 Ω

SUB OUT

Amplified output 400 W × 1 @ 4Ω with Low Pass filtering, optimized to drive a single external subwoofer or dual voice coil, or a pair of subwoofers.

SUB OUT AMPLIFIED OUTPUT CHANNEL

SUB OUT MODE

SUB 400 W @ 4 Ω / 600 W @ 2 Ω

Example 1: Connection to a single voice coil subwoofer (minimum 2 Ohms). It is recommended to connect SUB OUT+ and SUB OUT- outputs in parallel to achieve higher current capacity.

Alternatively, you can use only one of the two SUB OUT+/- outputs, at your discretion.

Example 2: Connection to a dual voice coil subwoofer (minimum 4+4 Ohms)

Example 3: Connection to two subwoofers (minimum 4 Ohms)

 

 

AF C8.14 bit

Supplied with a 16-pin cable that allows connection of up to 8 amplified SPK OUT channels, delivering 65 W × 8 @ 4Ω, connectable using the dedicated cable provided.

Example of Bridged Channel Connection

CH 1 ÷ CH 8 AMPLIFIED OUTPUT CHANNELS CONFIGURATION

POWER CHANNEL CONFIG
STEREO MODE	BRIDGE MODE
CH1 65 W @ 4 Ω / 100 W @ 2 Ω CH2 65 W @ 4 Ω / 100 W @ 2 Ω	CH1+ / CH2- 200 W @ 4 Ω
CH3 65 W @ 4 Ω / 100 W @ 2 Ω CH4 65 W @ 4 Ω / 100 W @ 2 Ω	CH3+ / CH4- 200 W @ 4 Ω
CH5 65 W @ 4 Ω / 100 W @ 2 Ω CH6 65 W @ 4 Ω / 100 W @ 2 Ω	CH5+ / CH6- 200 W @ 4 Ω
CH7 65 W @ 4 Ω / 100 W @ 2 Ω CH8 65 W @ 4 Ω / 100 W @ 2 Ω	CH7+ / CH8- 200 W @ 4 Ω

 

 

AF M8.14 bit

Supplied with a 16-pin cable that allows connection of up to 8 amplified SPK OUT channels, delivering 90 W × 8 @ 4Ω, connectable using the dedicated cable provided.

Example of Bridged Channel Connection

CH 1 ÷ CH 8 AMPLIFIED OUTPUT CHANNELS CONFIGURATION

POWER CHANNEL CONFIG
STEREO MODE	BRIDGE MODE
CH1 90 W @4ohm, 140W @2 Ω CH2 90 W @4ohm, 140W @2 Ω	CH1+ / CH2- 280 W @ 4 Ω
CH3 90 W @4ohm, 140W @2 Ω CH4 90 W @4ohm, 140W @2 Ω	CH3+ / CH4- 280 W @ 4 Ω
CH5 90 W @4ohm, 140W @2 Ω CH6 90 W @4ohm, 140W @2 Ω	CH5+ / CH6- 280 W @ 4 Ω
CH7 90 W @4ohm, 140W @2 Ω CH8 90 W @4ohm, 140W @2 Ω	CH7+ / CH8- 280 W @ 4 Ω

 

AF M12.14 bit

Supplied with a 24-pin cable that allows connection of up to 12 amplified SPK OUT channels, delivering 60 W × 12 @ 4Ω.

Example of Bridged Channel Connection

CH 1 ÷ CH 12 AMPLIFIED OUTPUT CHANNELS CONFIGURATION

POWER CHANNEL CONFIG
STEREO MODE	BRIDGE MODE
CH1 60 W @ 4 Ω / 90 W @ 2 Ω CH2 60 W @ 4 Ω / 90 W @ 2 Ω	CH1+ / CH2- 180 W @ 4 Ω
CH3 60 W @ 4 Ω / 90 W @ 2 Ω CH4 60 W @ 4 Ω / 90 W @ 2 Ω	CH3+ / CH4- 180 W @ 4 Ω
CH5 60 W @ 4 Ω / 90 W @ 2 Ω CH6 60 W @ 4 Ω / 90 W @ 2 Ω	CH5+ / CH6- 180 W @ 4 Ω
CH7 60 W @ 4 Ω / 90 W @ 2 Ω CH8 60 W @ 4 Ω / 90 W @ 2 Ω	CH7+ / CH8- 180 W @ 4 Ω
CH9 60 W @ 4 Ω / 90 W @ 2 Ω CH10 60 W @ 4 Ω / 90 W @ 2 Ω	CH9+ / CH10- 180 W @ 4 Ω
CH11 60 W @ 4 Ω / 90 W @ 2 Ω CH12 60 W @ 4 Ω / 90 W @ 2 Ω	CH11+ / CH12- 180 W @ 4 Ω

 

SPEAKER IN

The AF bit amplifier includes a 16-pin connector that can accept up to eight high-level signal channels. Channels 1 and 2 on this connector support the amplifier’s automatic turn-on function from high-level inputs (ART).
These inputs accept signals with a voltage level between 2.2 and 22 VRMS.

IMPORTANT: Speaker signals exceeding 22 VRMS can damage the amplifier. When signals exceed 22V AC RMS, the voltage must be attenuated—either with an external device such as the Connection SLI 2.2 or SLI 4.2, or by using the optional F4IN expansion board (which can handle up to 32V AC RMS).

Examples of SPEAKER IN Channel Connections:

Example 1. SPEAKER INPUT: 2 WAY FRONT + REAR

Example 2. SPEAKER INPUT: 2 WAY FRONT + REAR + CENTER + SUB

Example 3. SPEAKER IN (12Ch): 3 WAY FRONT + REAR + 2 WAY CENTER + SUB STEREO

PRE IN

Connector for low level inputs (0.6 ÷ 6 VMRS).

Each AF bit box includes a PRE IN cable with spare wires, to connect up to 8 low level signals from aftermarket headunits.

Connect the RCA outputs of the aftermarket head unit to the RCA inputs of the PRE-IN wiring using a high-quality RCA cable. 

NOTE: Make sure the PRE-IN wiring is plugged into the correct connector. If it is inserted into the SPEAKER IN connector, the audio signal will be attenuated.

Example 1. PRE IN: FRONT + REAR + CENTER + SUB

Example 2. PRE IN: 2 WAY FRONT + REAR + CENTER + SUB

USB PORT

The Micro USB port allows the AF bit amplifier to be connected to a compatible PC to manage functions using the bit Drive software. The connection standard is compatible with USB 2.0/3.0.

ART SWITCH

• OFF: ART function (automatic turn-on from high-level signal) is disabled.
• RESCUE: recovery mode in case of product malfunction. Refer to the manual for further instructions. RECOVERY MODE.
• ON: ART function (accensione automatica da segnale alto livello) enabled.

FUSE

The AF bit is equipped with blade-type fuses. If it becomes necessary to replace the amplifier fuse, only use a fuse of the same type and with the same rating as the original.

IMPORTANT: These fuses fit very tightly in their holders and may require the use of pliers for removal.

The table below shows the fuse rating for each AF bit model:

AF BIT MODEL	FUSE
AF M1.7 BIT	2 X 35 A
AF C4.10 BIT	1 X 30 A
AF M5.11 BIT	2 X 30 A
AF C8.14 BIT	1 X 35 A
AF M8.14 BIT	2 X 30 A
AF M12.14 BIT	2 X 30 A

LOGO - STATUS INDICATOR

AF bit amplifiers are controlled by a microprocessor that continuously monitors the status and connections of the device. If certain conditions are detected, the amplifier may mute the audio or shut down to protect itself.

The illuminated logo also functions as a status indicator, displaying a code that allows identification of the detected condition.

Steady BLUE:AF bit is powered on.

Flashing BLUE (alternating):AF bit is in the process of turning on or off. During these phases, the amplifier outputs are muted for safety.

Flashing RED (1 sec. ON / 1 sec. OFF):Thermal protection active. The AF bit has reached a temperature of 75°C, triggering thermal protection. Normal operation resumes when the temperature drops to approximately 70°C.

Flashing RED (½ sec. ON / ½ sec. OFF):Protection active due to one of the following conditions:

￭ Output overload. The red LED flashes when the output load drops below the minimum allowed impedance (approx. 2Ω).
The LED stays solid red when the protection is triggered.
If audio stops for a few seconds during music playback, check if the red LED is flashing — this indicates an overload.
Turn off the amplifier and inspect the speakers and wiring.
Note: This protection is self-resetting.

￭ Speaker cable fault. The red LED flashes when a speaker terminal or cable is shorted to the vehicle chassis.
If audio stops for a few seconds during music playback, check if the red LED is flashing — this indicates a short circuit between a speaker terminal and the chassis.
Turn off the amplifier and inspect the speakers and wiring.
Note: This protection is self-resetting.

Flashing RED (¼ sec. ON / ¼ sec. OFF) indicates:

￭ OVER VOLTAGE protection is active due to battery voltage exceeding 17V. The amplifier will shut down after 3 minutes in over-voltage condition.
⚠️ WARNING: CHECK THE VEHICLE’S ALTERNATOR AND CHARGING SYSTEM.

Most vehicles should not exceed +15V DC.

Steady RED:The amplifier attempted to deliver DC current to a speaker, triggering internal protection.
This indicates a hardware failure.
Please contact your local authorized service center.

OPTIONAL CONNECTIONS

DRCC

Connection port for the optional DRC AC or DRC MP CAN controller.

OPTICAL IN (TOSLINK optical input)

AF bit amplifiers feature a TOSLINK optical digital input, which accepts PCM signals with sampling rates up to 192 kHz and 24-bit resolution. To use it, connect a fiber optic cable with TOSLINK connector, plug the other end into a compatible source, and enable the input via the bit Drive software.

Ways to select the OPTICAL IN input:

• From the DRC AC or DRC MP CAN controller.
• Using the Auto Input Switch function available in the bit Drive software.
• Via one of the “CONTROL” terminals properly configured. This command is activated by applying +12V to the terminal.
• Through the ADC port with a compatible device (e.g., Audison B-CON).
• Through the MAESTRO port with a compatible device.
• Via the B-CON go app (if a B-CON is connected via ADC cable).

Note: Multichannel signals such as DOLBY DIGITAL (AC3) or DTS from AV sources (e.g., DVD movie audio) cannot be reproduced. The TOSLINK input only supports stereo PCM signals. The output of such devices must be set to STEREO mode for the signal to be played correctly.

.

DSP OUT

All AF bit amplifiers are equipped with a DSP OUT preamplified output connector with 6 preamp output channels, allowing the internal bit processor to manage the signals sent to external AF D amplifiers (or others).

Note: the only exception is the AF M12.14, which features only two unique preamp output channels, outputs 5 and 6. Outputs #1-4 mirror the signal on amplified channels #9-12.

This connector can be used with the DSP OUT cable (included) or with the AF LINK cable (not included).

- DSP OUT cable (included):

Example 1:

- AF LINK cable (not included):

Examples 1 and 2: With the optional AF LINK cable, the DSP OUT output of the AF M5.11 bit can be connected to one or more Audison AF D amplifiers (models without DSP), allowing the audio system to be expanded up to 11 output channels

Example 3: If the AF LINK cable is not available, it is still possible to connect the DSP OUT signals from the AF bit to one or more Audison AF D amplifiers (models without DSP).

Example 4: If using another amplifier with RCA PRE-IN inputs, the supplied DSP OUT cable must be properly soldered with RCA connectors.

Note: it is recommended to ensure that the input signal levels of the amplifier are compatible with the DSP OUT output levels.

Example 2

Example 3

Example 4

MAESTRO PORT

Dedicated port for communication with iDatalink Maestro AR devices. Refer to the
bit Drive manual - How to tune with Maestro AR for more details.

ADC PORT (AUDISON DATA CONTROL)

Port for serial communication with compatible external devices (e.g., Audison B-CON).

Note: for advanced users, it is possible to develop custom external interfaces that communicate with the amplifier via this serial port (e.g., steering wheel control interfaces).

If interested, please contact Audison technical support for more information.

INPUT EXPANSION SLOT

AF bit amplifiers support two additional optional accessories (F4IN / F2O), which can be inserted into the dedicated slot located on the right side of the product.
To do so, it is necessary to remove the screws and the panel.

IMPORTANT: follow these steps to properly install the F4IN or F2O accessory board:

1.  

   1. Power off the amplifier;

   2. Insert the F4IN or F2O board into the dedicated slot;

   3. Power on the amplifier and launch the bit Drive software;

      ⚠️WARNING: if the amplifier already contains a configuration saved in memory, created before the accessory board was installed, that configuration will not be compatible with the new hardware setup and cannot be loaded.

      If you wish to recreate a similar configuration, save the current one to your PC for later consultation in Offline mode;

   4. Open the Settings menu and select the Reset device command to properly detect the additional channels of the accessory board (refer to section 2.2 of the bit Drive manual for further details).

￭ F4IN (Forza 4 Input): (Forza 4 Input): adds four high-voltage SPEAKER IN channels, increasing the total from eight to twelve. These four channels support an input sensitivity range of 3.2÷32 VRMS.

Connect the 4CH Speaker IN cable (included with this module) as shown in figure 3.

4CH Speaker IN input cable:

IMPORTANT: compared to the 8 native SPK IN inputs, the F4IN input sensitivity range is 3.2 ÷ 32 VRMS, allowing integration into advanced OEM systems that require higher input voltages.

In the bit Drive software, the F4IN channels are always identified as #9, #10, #11, #12.

Refer to the table below for correct sensitivity calibration of each F4IN input.

bit Drive input sensitivity [VRMS]	F4IN applied sensitivity [VRMS]
22	32
21,3	31
20,5	29,8
19,8	28,8
19,1	27,8
18,3	26,6
17,6	25,6
16,9	24,6
16,1	23,4
15,4	22,4
14,7	21,4
13,9	20,2
13,2	19,2
12,5	18,2
11,7	17
11	16
10,3	15
9,5	13,8
8,8	12,8
8,1	11,8
7,3	10,6
6,6	9,6
5,9	8,6
5,1	7,4
4,4	6,4
3,7	5,4
3,3	4,8
2,9	4,2
2,6	3,8
2,2	3,2

￭ F2O (Forza 2^nd Optical): adds a second digital input, Toslink or coaxial (up to 192 kHz / 24 bit), selectable via a dedicated switch on the module itself.

Note: the Absolute Volume function is not available on this module.
Therefore, when using a B-CON or other accessories compatible with this function, it is recommended to use the main optical input of the AF bit.

COAXIAL input cable:

Note: the digital input accepts stereo PCM signals up to 192 kHz / 24 bit.
Therefore, multichannel signals such as DOLBY DIGITAL (AC3) or DTS, typically from A/V sources (e.g., DVD movie audio), cannot be played back.
The output of such devices must be set to STEREO mode for the signal to be properly reproduced.

OPTICAL 2 input selection methods:

• Using the DRC AC, by selecting the OPTICAL input;

• Using one of the CONTROL inputs, properly configured (refer to the bit Drive software documentation). This input is activated by connecting the wire to +12V;

• Using the bit Drive PC software.

5. HOW TO TURN ON THE AF bit

There are four different ways to turn on the amplifier:

1. by ART: automatic turn-on from BTL signal with high-level OEM sources.

IMPORTANT: the ART function is only active on SPEAKER IN inputs #1 and #2

2. by REM IN: turn-on via REM IN input (blue wire), available in the CONTROL cable.

A 12 VDC signal must be supplied to this terminal

Note: If the amplifier is powered on via the Remote IN input, it can only be turned off using the same Remote IN.

3. by DRC AC:

◼︎ Power On: Turn on the AF bit by gently pressing the DRC AC knob.

◼︎ Power Off: Turn off by pressing and holding the DRC AC knob.

4. Via DRC MP CAN:

◼︎ Power On: Turn on the AF bit by pressing and holding the ESC button on the DRC MP CAN for 3 seconds.

◼︎ Power Off: Turn off by pressing and holding the ESC button on the DRC MP CAN for 3 seconds.

In both cases, no additional wiring is required for powering on.

Note: If the amplifier is powered on via DRC AC or DRC MP CAN, it can be turned off by using DRC AC, DRC MP CAN, or the Remote IN input.

5.1 Programmable Turn On/Off delays

from bitDrive software it is possible to set the Turn On-Off delay settings This functions are useful when the AF bit is connected to other companion amplifiers (like for example AF M6D, AF M4D or any other amplifier without integrated Dsp.), in order to  avoid bumps or similar bad sound effects due to the turn on/off latencies between the amplifiers in the same system.

Please read section 7.6.1 Turn On/Off delay of bit Drive manual.

Turn on delay

Programmable time delay that the AF bit waits before turning on after that it received ART (SPK IN input signal on CH1 or Ch2) or REM IN signal.

The sequence of events is:

• AF bit receives ART or REM IN signal
• the REM OUT signal of AF bit activates immediately and turns on the companion amplifer(s)
• the AF bit turns on after the programmed Turn on delay

Turn off delay 

Programmable time delay that the AF bit waits before turning off after that the ART (SPK IN input signal on CH1 or Ch2) or REM IN signal is removed to turn off the system.

The sequence of events is:

• ART or REM IN signal is removed from the AF bit
• the REM OUT signal of AF bit deactivates immediately and turns off the companion amplifer(s)
• the AF bit turns off after the programmed Turn off delay

6. FIRMWARE UPGRADE

Please, read chapter 1. SOFTWARE AND FIRMWARE INSTALLATION AND MAINTENANCE of bitDrive user manual.

7. RESCUE PROCEDURE

These procedure must be used in case of FW upgrades that were not succesfully completed, which cause missing turn on of the amplifier or other malfunctionings.

• Disconnect the supply from the AF bit or remove the fuse and wait at least for 20 seconds

• Put the switch in position “RESCUE MODE” and wait at least for 20 seconds.

• Reconnect the supply of the AF bit or insert the fuse previously removed, and turn on the supply
• The logo of the AF bit will start blinking, meaning that the device is ready to be upgrade in Rescue mode.
• Download the firmware from the Audison website. A folder named AFUpdate (vx.x.x.x) will be available in the Downloads folder.
• Open the folder AFUpdate (vx.x.x.x), click the file AFUpdate. The following window will appear:
  
• Make sure to read all the warnings, then click Update to start the procedure.

• Wait until the operation is completed before disconnecting the USB cable or removing power from the bit device or the PC. At the end the followin message will appear:

• Click OK and disconnect the supply from the AF bit or remove the fuse and wait at least for 20 seconds.

• Put the switch from position RESCUE to the position ART ON/OFF and wait at least for 20 seconds. 

• Reconnect the supply or insert the fuse previously removed.

• Connect the USB cable between AF bit and PC, turn on the amplifier.
• Open the bit Drive software and check that the firmware has been correctly installed.

8. BIT DRIVE SOFTWARE - HOW TO TUNE YOUR AF bit

BIT DRIVE SOFTWARE - USER MANUAL

9. FAQ - Frequently asked questions

FAQ - Frequently Asked Questions