V Eight DSP MK2 - Receiver Audiotec Fischer - Free user manual and instructions

Product Type	8-Channel Amplifier with Integrated DSP
Brand	Audiotec Fischer
Model	V Eight DSP MK2
Dimensions (H x W x D)	44 x 220 x 180 mm (1.73 x 8.66 x 7.09 in)
Operating Voltage	10.5 - 16 V (6 V for up to 5 sec)
Idle Current	540 mA
Fuse Rating	2 x 30 A LP-Mini-Fuse (APS)
Output Power (RMS, 4 Ω)	75 W per channel
Output Power (RMS, 2 Ω)	120 W per channel
Max Output Power	Up to 160 W RMS per channel @ 2 Ω
Amplifier Technology	Pure Class GD
Inputs	6 x RCA/Cinch, 8 x Highlevel speaker, 1 x Optical SPDIF (12-96 kHz), 1 x Remote In
Outputs	8 x Speaker, 2 x RCA/Cinch, 2 x Remote Out
DSP Resolution	64 Bit
Sampling Rate	48 kHz
Signal-to-Noise Ratio (Digital Input)	107 dB (A-weighted)
Signal-to-Noise Ratio (Analog Input)	102 dB (A-weighted)
Total Harmonic Distortion (THD)	< 0.015 %
Frequency Response	20 Hz - 22,000 Hz
Additional Features	HEC slot, ADEP.3 circuit, Control Input, 32 Bit CoProcessor, Auto Remote switch, Power Save Mode, Start-Stop capability, Virtual Channel Processing (VCP)
Installation & Maintenance Tips	Disconnect battery before installation; clean with dry cloth; ensure proper ventilation; avoid moisture and extreme temperatures.
Safety Precautions	Use main fuse within 30 cm of battery; use correct cable cross-section; never connect speaker outputs to ground; adjust input sensitivity properly.
Spare Parts / Repairability	HEC modules available for expansion; replace fuses with identical rating; internal jumpers for input sensitivity adjustment.

Frequently Asked Questions - V Eight DSP MK2 Audiotec Fischer

What is the V Eight DSP MK2?

The V Eight DSP MK2 is an 8-channel amplifier with integrated digital signal processor (DSP) by Audiotec Fischer, offering high-quality sound tuning and flexible system configuration.

How do I connect the amplifier to my PC?

Use the provided USB cable to connect the USB Input to your PC. Install the DSP PC-Tool software from the Audiotec Fischer website before connecting. The software allows full configuration of the DSP.

What is Virtual Channel Processing (VCP)?

VCP is a multi-stage signal processing concept that adds an additional layer of eight virtual channels between inputs and outputs. It enables cross-channel group equalizers, multi-way speaker configurations for DSP sound effects, and features like Rear Attenuation.

How do I adjust the input sensitivity?

Use the Gain control on the device or configure it via DSP PC-Tool. For high-level inputs with voltages between 11 V and 32 V, you must remove the Load Jumper inside the device. Refer to the manual for jumper positions and extended adjustment ranges.

What does the Status LED indicate?

Green: amplifier ready. Orange: Power Save Mode active. Red: Protection Mode (over/undervoltage, overheating). Red/green slow flashing: no operating software (connect to PC-Tool). Red/green fast flashing: selected memory slot is empty.

Can I use both high-level and low-level inputs simultaneously?

No, you must not use both inputs on the same channel simultaneously as it may damage the head unit's outputs. However, you may use high-level inputs on some channels and low-level inputs on others.

What is the Power Save Mode?

After 60 seconds of no input signal, the amplifier reduces power consumption by turning off the remote output and connected amplifiers. It reactivates within one second when a signal is detected. The delay time can be adjusted or the mode deactivated via DSP PC-Tool.

How do I install a HELIX Extension Card (HEC)?

Disconnect all cables, remove the side panel near the USB input, insert the HEC module into the designated slot, ensure proper pin connection, reattach the new side panel, and reconnect cables. The module is automatically detected.

What is the ADEP.3 circuit?

The Advanced Diagnostics Error Protection (3rd generation) prevents error messages and feature loss when connecting the amplifier to modern factory radios with speaker diagnostics. It avoids loading the OEM radio's outputs unnecessarily.

What should I do if the amplifier goes into protection mode?

Check for short circuits, incorrect connections, or overheating. Ensure proper ventilation and that the operating voltage is within 10.5-16 V. If overheating, the amplifier will automatically resume operation when cooled. If the issue persists, consult an authorized dealer.

USER MANUAL V Eight DSP MK2 Audiotec Fischer

8-channel amplifier with integrated DSP

Kanal A = Vorne links

Kanal C = Hinten links

Close-up of a circuit board with electronic components and a highlighted electronic component (no readable text or symbols)

Close-up of a computer motherboard with visible circuitry and components, marked with green and blue boxes (no readable text or symbols)

Konfiguration des Virtual Channel Processing (VCP)

Remote Output Configuration

Close-up of electronic circuit board with multiple LED connectors and a green checkmark overlay (no readable text or symbols)

Close-up of a computer motherboard with visible electronic components and a red X symbol overlay (no readable text or symbols)

ACO – Advanced 32 Bit CoProcessor

Abtastrate ....48 kHz

Congratulations on your purchase of this innovative and high-qual ity HELIX product.

Thanks to more than 30 years of experience in research and development of audio products the HELIX V EIGHT DSP MK2 sets new standards in the range of digital amplifiers.

We wish you many hours of enjoyment with your new HELIX V EIGHT DSP MK2.

Yours,

AUDIOTEC FISCHER

General instructions

General installation instructions for HELIX components

To prevent damage to the unit and possible injury, read this manual carefully and follow all installation instructions. This product has been checked for proper function prior to shipping and is guaranteed against manufacturing defects.

Before starting your installation, disconnect the battery's negative terminal to prevent damage to the unit, fire and / or risk of injury. For a proper performance and to ensure full warranty coverage, we strongly recommend to get this product installed by an authorized HELIX dealer.

Install your HELIX V EIGHT DSP MK2 in a dry location with sufficient air circulation for proper cooling of the equipment. The amplifier should be secured to a solid mounting surface using proper mounting hardware. Before mounting, carefully examine the area around and behind the proposed installation location to insure that there are no electrical cables or components, hydraulic brake lines or any part of the fuel tank located behind the mounting surface. Failure to do so may result in unpredictable damage to these components and possible costly repairs to the vehicle.

General instruction for connecting the HELIX V EIGHT DSP MK2 amplifier

The HELIX V EIGHT DSP MK2 amplifier may only be installed in vehicles which have a 12 Volts negative terminal connected to the chassis ground. Any other system could cause damage to the amplifier and the electrical system of the vehicle.

The positive cable from the battery for the complete system should be provided with a main fuse at a distance of max. 30 cm from the battery. The value of the fuse is calculated from the maximum total current input of the car audio system.

Use only suitable cables with sufficient cable cross-section for the connection of HELIX V EIGHT DSP MK2. The fuses may only be replaced by identically rated fuses (2 x 30 A) to avoid damage of the amplifier.

Prior to installation, plan the wire routing to avoid any possible damage to the wire harness. All cabling should be protected against possible crushing or pinching hazards. Also avoid routing cables close to potential noise sources such as electric motors, high power accessories and other vehicleharnesses.

Connectors and control units

① USB Input

Connects the HELIX V EIGHT DSP MK2 to your PC.

② Control Input

Multifunction interface for e.g. an optional remote control or other HELIX accessory.

③ Control pushbutton

Use this button to either switch between the setups or initiate a reset of the device.

④ Status LED

This LED indicates the operating mode of the amplifier and of its memory.

⑤ Optical Input

Optical input for digital stereo signals (SPDIF format).

⑥ Line Input

RCA inputs for connecting pre-amplifier signals.

⑦ Highlevel Input

Highlevel speaker inputs for connecting a factory radio or an aftermarket radio without lowlevel line outputs.

⑧ Clipping LED

This LED lights up red if one of the analog inputs is overdriven.

⑨ Gain

Control for adjusting the input sensitivity of the lowlevel Line and Highlevel Inputs.

10 Output Channels

Speaker outputs for connecting speaker systems.

11 GND

Connector for the ground cable (negative terminal of the battery or metal body of the vehicle).

12 REM

Connector for the remote cable.

⑬ +12 V

Connector for the +12 V power cable to the

positive terminal of the battery.

14 Line Output

Line outputs for connecting external amplifiers. Make sure that the remote output (Rem Out) is used to turn on these devices.

15 Rem Out

The remote output has to be used to turn on/off external amplifiers that are connected to the RCA / Cinch line outputs. Both connections are internally wired in parallel.

① USB Input

Connect your personal computer to the V EIGHT DSP MK2 using the provided USB cable. The required PC software to configure this amplifier can be downloaded from the Audiotec Fischer website www.audiotec-fischer.com.

Please note: It is not possible to connect any USB storage devices.

② Control Input

This multi-functional input is designed for HELIX V EIGHT DSP MK2 accessory products like a remote control which allows to adjust several features of the amplifier. Depending on the type of remote control, at first its functionality has to be defined in the “Device Configuration Menu” of the DSP PC-Tool software.

③ Control pushbutton

The V EIGHT DSP provides 10 internal memory locations for sound setups. The Control pushbutton allows the user to switch between two memory positions. These can be defined in the DSP PC-Tool. Pressing the button for five seconds completely erases the internal memory. This is indicated by a continuous red glowing and constant green flashing of the Status LED.

Note: The memory locations one and two are defined ex works. To manually switch between the setups the button has to be pressed and held for one second. Switching is indicated by a single red flash of the Status LED. To switch between all internal memory locations, the optionally available DIRECTOR display remote control or the HELIX WIFI CONTROL is recommended.

Attention: After erasing the setups from memory the HELIX V EIGHT DSP MK2 will not reproduce any audio output.

④ Status LED

The Status LED indicates the operating mode of the amplifier and of its memory.

Green: Amplifier is ready for operation.

Orange: Power Save Mode is active.

Red: Protection Mode is active. This may have different root causes. The HELIX V EIGHT DSP MK2 is equipped with protection circuits against over- and undervoltage as well as overheating. Please check for connecting failures such as short-circuits or other wrong connections.

If the amplifier is overheated the internal temperature protection switches off the remote and signal output until it reaches a safe temperature level again.

Red / green slow flashing: No operating software installed. Connect the amplifier to the DSP PC-Tool software and confirm the automatic update of the operating system. You will find the latest version of the DSP PC-Tool software at www.audiotec-fischer.com.

Red / green fast flashing: The currently selected sound setup memory is empty. A new setup has to be loaded via the DSP PC-Tool software or switch to a memory position with existing sound setup.

⑤ Optical Input

Optical input in SPDIF format for connecting signal sources with a digital audio output. The sampling rate of this input must be between 12 and 96 kHz. The input signal is automatically adapted to the internal sample rate.

In order to control the volume of this input, we recommend to use an optional remote control or the WIFI CONTROL.

Note: This amplifier can only handle stereo input signals and no MP3- or Dolby-coded digital audio stream!

Note: In standard configuration the manual activation via an optional remote control is configured.

⑥ Highlevel Input

8-channel highlevel loudspeaker input to connect the amplifier directly to loudspeaker outputs of OEM / aftermarket radios or OEM amplifiers that do not have any pre-amplifier outputs. Input sensitivity is factory-set to 11 Volts (see the following picture).

However, it is possible to optimally adapt the input sensitivity to the signal source using control 9 (Gain) and by repositioning jumpers inside the device (see page 28, item 4; Signal configuration).

Important: If the input sensitivity of a channel is set between 11 V and 32 V, it is mandatory to remove the Load Jumper inside the device before first use (see page 28, item 4; Signal configuration). Disregarding this may cause severe damage to the amplifier.

Attention: Solely use the pluggable screw-terminal for the highlevel connector which is included in delivery or an optional available cable harness from the HELIX accessory assortment!

Important: It is strictly forbidden to use the High-level Input and lowlevel Line Input of an individual channel at the same time as this may cause severe damage to the lowlevel line outputs of your car radio. Nevertheless it is possible to use the Highlevel Input of one channel and the lowlevel Line Input of another channel simultaneously.

⑦ Line Input

6-channel pre-amplifier input to connect signal sources such as radios. Input sensitivity is factory-set to approx. 3 Volts.

However, it is possible to optimally adapt the input sensitivity to the signal source using control 9 (Gain) and by repositioning jumpers inside the device (see page 28, item 4; Signal configuration).

⑧ Clipping LED

This LED lights up red if one of the six Line Inputs or eight Highlevel Inputs is overdriven. The LED has no function if the device is fed with digital input signals. If this LED lights up reduce the input sensitivity by using the control 9 (Gain) until the LED goes out.

⑨ Gain

This control is used to adapt the input sensitivity of the low- and highlevel inputs to the output voltage of the connected signal source. This is not a volume control, it's only for adjusting the amplifier gain. The control range of the RCA / Line Input is factory-set to 1 - 4 Volts and 4 - 16 Volts for the Highlevel Input. The input sensitivity range can be changed by repositioning jumpers inside the device.

Alternatively, the input sensitivity can be set using the DSP PC-Tool software. Therefore, the function has to be activated and configured in the "Signal management" tab of the DCM menu (see the following picture).

Important: If the input sensitivity of a channel is set between 11 V and 32 V, it is mandatory to remove the Load Jumper inside the device before first use (see page 28, item 4; Signal configuration). Disregarding this may cause severe damage to the amplifier.

Attention: It is mandatory to properly adapt the input sensitivity of the V EIGHT DSP MK2 to the signal source in order to avoid damage to the amplifier.

⑩ Output Channels

Speaker outputs to connect speaker systems. The impedance per channel must not be lower than 2 Ohms.

Important: We highly recommend to make the general settings in the DSP PC-Tool software before the

first start-up. Especially if the V EIGHT DSP MK2 will be used to drive fully active speaker systems, a wrong setup can destroy your tweeters right away.

⑪ GND

The ground cable should be connected to a common ground reference point (this is located where the negative terminal of the battery is grounded to the metal body of the vehicle) or to a prepared metal location on the vehicle chassis i.e. an area which has been cleaned of all paint residues. Recommended cross section: min. 16 mm ^2 / AWG 6.

⑫ REM

The remote input has to be used to turn on / off the V EIGHT DSP MK2 if the signal source which is connected to the Highlevel Input is not activating the “automatic turn-on” function or if the amplifier shall only be activated / deactivated by a remote signal applied to the remote input. The remote lead should be connected to the remote output / automatic antenna (aerial positive) output of the head unit / car radio. This is only activated if the head unit is switched on. Thus the amplifier is switched on and off together with the head unit. This input need-n’t to be assigned if the Highlevel Input is used. To deactivate the “automatic turn-on” function read the description on page 30, item 7; Configuration of the remote input.

⑬ +12 V

Connect the +12 V power cable to the positive terminal of the battery. Recommended cross section: min. 16 mm ^4 / AWG 6.

14 Line Output

Processed 2-channel pre-amplifier output with a maximum output voltage of 3 Volts RMS for connecting additional power amplifiers. Please make sure that you always turn on / off external amplifiers using the remote output (Rem Out) of the V EIGHT DSP MK2. Never directly control the external amps by a signal from the ignition switch of your car! Additionally this output will be turned off when the "Power Save Mode" of the amplifier is active. The outputs can be assigned to any of the inputs as desired using the DSP PC-Tool software.

15 Rem Out

We strongly recommend to use this output for turning on / off additional amplifiers that are connected to the Line Output of the HELIX V EIGHT DSP MK2. This is essential to avoid any interfering signals. This output is activated automatically as soon as the booting process of the DSP is completed. Additionally this output will be turned off during the "Power Save Mode" or a software update process.

Connection of HELIX V EIGHT DSP MK2 to the head unit / car radio:

Caution: Carrying out the following steps will require special tools and technical knowledge. In order to avoid connection mistakes and / or damage, ask your dealer for assistance if you have any questions and follow all instructions in this manual (see page 15). It is recommended that this unit will be installed by an authorized HELIX dealer.

1. Connecting the pre-amplifier inputs

Use the correct cable (RCA / cinch cable) to connect these inputs to the pre-amplifier / lowlev el / cinch outputs of your head unit / car radio. Each input can be assigned to any output using the DSP PC-Tool software. The automatic turn-on circuit does not work when using the pre-amplifier inputs. In this case the remote input has to be connected to activate the HELIX V EIGHT DSP MK2.

Important: It is strictly forbidden to use the Highlevel and lowlevel Line Input of an individual channel at the same time as this may cause severe damage to the lowlevel line outputs of your head unit / car radio. Nevertheless it is possible to use the Highlevel Input of one channel and the lowlevel Line Input of another channel simultaneously.

2. Connecting the highlevel speaker inputs

The highlevel loudspeaker inputs can be connected directly to the loudspeaker outputs of an OEM or aftermarket radio using appropriate cables (loudspeaker cables with 1 mm^2 / AWG 18 max. ).

We recommend the following channel assignment if a common car radio will be connected to the signal processor:

Channel A = Front left

Channel B = Front right

Channel C = Rear left

Channel D = Rear right

Actually it is not mandatory to use all high level speaker inputs. If only two channels will be connected we recommend to use the channels A and B. Make sure that the polarity is correct. If one or more connections have reversed polarity it may affect the performance of the amplifier.

If this input is used the remote input does not need to be connected as the amplifier will automatically turn on once a loudspeaker signal is received.

3. Connecting a digital signal source

If you have a signal source with an optical digital output you can connect it to the amplifier using the appropriate input. In standard configuration the manual activation via an optional remote control is configured.

Alternatively you can activate the automatic turn-on feature in the DCM menu of the DSP PC-Tool software. The feature activates the digital input as soon as a digital audio signal is detected.

The automatic turn-on circuit does not work when a digital input is used. Therefore it is mandatory to connect the remote input (REM).

Important: The signal of a digital audio source normally does not contain any information about the volume level. Keep in mind that this will lead to full level on the outputs of the HELIX V EIGHT DSP MK2 and your connected amplifiers. This may cause severe damage to your speakers. We strongly recommend to use an optional remote control for adjusting the volume level of the digital signal input!

Information: The HELIX V EIGHT DSP MK2 can only handle uncompressed digital stereo signals in PCM format with a sample rate between 12 kHz and 96 kHz and no MP3- or Dol-by-coded digital audio stream!

4. Signal configuration

The factory setting of the input sensitivity as well as the load of the highlevel inputs of the V EIGHT DSP MK2 are appropriate for the most common radios. As soon as the connected signal source provides an input voltage between 11 V and 32 V – e.g. if an OEM amplifier is used as signal source – please follow the subsequent steps 4.1 and 4.2. If you are not sure regarding the signal sources output voltage, please contact your HELIX specialist dealer.

4.1 Adjustment of the highlevel input load Attention: If the highlevel input is used as signal input it is mandatory to adapt its load to the input voltage in order to avoid damage to the amplifier.

As soon as the input sensitivity is set between 11 V and 32 V, the Load Jumper inside the device has to be removed immediately. To get access to the Load Jumper the device has to be opened. Therefore dismantle the side panel where the USB input is located by removing the two Phillips and two Allen screws and pull out the bottom plate sideways.

To remove the Load Jumper (see marking in the picture below) simply pull it upwards.

4.2 Adjustment of the input sensitivity Attention: It is mandatory to properly adapt the input sensitivity of the V EIGHT DSP MK2 to the signal source in order to avoid damage to the amplifier.

Several adjustment examples are listed in the table on page 32.

If you want to change the input sensitivity use the Gain control 9 (see page 26, item 9). The setting of the control affects both the lowlevel and the highlevel inputs!

If the ex factory sensitivity range of the lowlevel input (1 - 4 Volts) or highlevel input (4 - 16 Volts) may not be sufficient it is possible to change it internally by repositioning jumpers. Therefore open the device as described in item 4.1.

For adjusting the extended adjustment range (Highlevel 8 - 32 Volts; RCA / Cinch 2 - 8 Volts) an additional jumper is included in scope of delivery. To change the position of a jumper it has to be removed by pulling it straight upwards. Make sure that the jumper is reinserted properly and all pins are fully inserted. The position of each jumper can be changed independently.

Overview plug-in positions:

A: Load Jumper for channel A - H

B: Extended adjustment range for channel A-D

C: Extended adjustment range for channel E - H

Ex factory jumper positions:

Plugged jumpers Value range
A (channel A - H)	Highlevel: 4 – 16 VoltsRCA : 1 – 4 Volts

Jumper positions for extended adjustment range:

Plugged jumpers Value range
B (channel A - D)	Highlevel: 8 – 32 VoltsRCA : 2 – 8 Volts
C (channel E - H)	Highlevel: 8 – 32 VoltsRCA : 2 – 8 Volts

Note: If only the input channels A to D are used, for the extended setting range it is sufficient to remove the Load Jumper and plug it to jumper position B.

Exact adjustment of the input sensitivity:

After you have adjusted the input load of the amplifier to the maximum output voltage of the signal source, follow the subsequent steps to optimally adapt the input sensitivity by using the Gain control.

1. Don't connect any amplifiers or loudspeakers to the outputs of the HELIX V EIGHT DSP MK2 during this setup.
2. Turn on the amplifier.
3. Adjust the volume of your radio to approx. 90 % of the max. volume and playback a 1 kHz full scale test tone (0 dB) via CD drive.
4. If the Clipping LED already lights up, you have to reduce the input sensitivity via Gain control (page 26, item 9) until the LED turns off.
5. Increase the input sensitivity by turning the control clockwise until the LED lights up. Now turn the control counterclockwise until the Clipping LED turns off again.

For further applications please contact your HELIX specialist dealer.

5. Connection to power supply

Make sure to disconnect the battery before installing the HELIX V EIGHT DSP MK2!

Connect the +12 V power cable to the positive terminal of the battery. The positive wire from the battery to the amplifier power terminals needs to have an inline fuse at a distance of less than 12 inches (30 cm) from the battery. The value of the fuse is calculated from the maximum total current draw of the whole car audio system (V EIGHT DSP MK2 = max. 60 A RMS at 12 V power supply). If your power wires are short (less than 1 m / 40") then a wire gauge of 16 mm² / AWG 6 will be sufficient. In all other cases we strongly recommend gauges of 25 - 35 mm² / AWG 4 - 2!

The ground cable (same gauge as the +12 V wire) should be connected to a common ground reference point (this is located where the negative terminal of the battery is grounded to the metal body of the vehicle), or to a prepared metal location on the vehicle chassis, i.e. an area which has been cleaned of all paint residues.

6. Connecting the remote input

The remote input (REM) has to be connected to the radio remote output if the amplifiers lowlevel Line Inputs or the Optical Input is solely / are used as signal input/s. We do not recommend controlling the remote input via the ignition switch to avoid pop noise during turn on / off. If the Highlevel Input is used this input does not need to be connected as long as the car radio has BTL output stages.

7. Configuration of the remote input

The V EIGHT DSP MK2 will be turned on automatically if the Highlevel Input is used or if a signal is applied to the remote input terminal. The "Auto Remote" switch allows to deactivate the automatic turn-on feature of the highlevel inputs. The feature should be deactivated (Auto Remote = Off) if there are e.g. noises while switching on / off the amplifier.

Note: If the automatic turn-on function is deac-

tivated it is mandatory to use the remote input terminal to power up the amplifier! The highlevel signal will be ignored in this case.

Note: The automatic turn-on feature of the highlevel inputs is activated ex works.

To deactivate the automatic turn-on feature you have to open the device and change the position of the "Auto Remote" switch. Therefore the device has to be opened as described in item 4.1. The switch is located near by the "Made in Germany" imprint (see marking in the following picture).

On: Activation via highlevel speaker input is enabled (ex works).

Off: Activation via highlevel speaker input is disabled.

8. Configuration of the internal DSP

The general DSP settings should be conducted with the DSP PC-Tool software before using the amplifier for the first time.

Ignoring this advice may result in damaging the connected amplifiers / loudspeakers. Information about connecting the V EIGHT DSP MK2 to a computer can be found on page 33.

9. Connecting the loudspeaker outputs

The loudspeaker outputs can be connected directly to the wires of the loudspeakers. Never connect any of the loudspeaker cables with the chassis ground as this will damage your amplifier and your speakers.

Ensure that the loudspeakers are correctly connected (in phase), i.e. plus to plus and minus to minus. Exchanging plus and minus causes a total loss of bass reproduction. The plus pole is indicated on most speakers. The impedance of the speakers must not be lower than 2 Ohms.

10. Connecting the remote output

This output (Rem Out) is used to supply remote signals to the external amplifier/s. Always use this remote output signal to turn on the amplifiers in order to avoid on / off switching noises.

Examples for adjusting the input sensitivity:

Source	Which input Jumperpositions		Position Gain control (9)
4- to 6-channel OEM-RadioUp to 25 Watts RMS power per channel at 4 Ohms or up to 50 Watts RMS power at 2 Ohms	HighlevelA - F	A pluggedB & C not plugged(see fig. 1)	11 V(delivery status)
OEM-Radio with additional 4- to 8-channels amplifier>25 Watts and up to 200 Watts RMS power at 4 Ohms or up to 100 Watts RMS power per channel at 8 Ohms	HighlevelA - H	A not pluggedB & C plugged(see fig. 2)	Typically max. CCW position
4- to 6-channel aftermarket radio with pre-amplifier outputs	Lowlevel /RCAA - F	A pluggedB & C not plugged(see fig. 1)	Typically delivery status (3 V);max. CCW position for radios with 4 Volts output voltage;max. CW position for radios with 1 Volt output voltage

Figure 1: Figure 2:

Close-up of a computer motherboard with visible electronic components and a highlighted chip (no readable text or symbols)

Close-up of a computer motherboard with visible circuit boards and components, marked with green and blue boxes (no readable text or symbols)

It is possible to freely configure the HELIX V EIGHT DSP MK2 with our DSP PC-Tool software. The user interface is designed for easy handling of all functions and allows an individual adjustment of each of the ten DSP channels. Prior to connecting the amplifier to your PC visit our website and download the latest version of the DSP PC-Tool software.

Check from time to time for software updates. You will find the software and the respective user manual on www.audiotec-fischer.com.

We strongly recommend to carefully read the user manual (Sound Tuning Magazine) before using the software for the first time in order to avoid any complications and failures.

Important: Make sure that the amplifier is not connected to your computer before the software and USB driver are installed!

In the following the most important steps how to connect and the first start-up are described:

1. Download the latest version of the DSP PC-Tool software (available on our website www.audiotec-fischer.com) and install it on your computer.

2. Connect the amplifier to your computer using the USB cable that is included in delivery. If you have to bridge longer distances please use an active USB extension cable with integrated repeater or the optionally available WIFICONTROLinterface.

3. First turn on the amplifier and then start the software. The operating software will be updated automatically to the latest version if it is not up-to-date.
4. Now you are able to configure your HELIX V EIGHT DSP MK2 with our intuitive DSP PC-Tool software. Nevertheless, interesting and useful hints can be found e.g. in our "Sound Tuning Magazine", which can be downloaded for free from our website.

Caution: We highly recommend to set the volume of your car radio to minimum position during first start-up. Additionally no devices should be connected to the amplifier until general settings in the DSP PC-Tool software have been made. Especially if the V EIGHT DSP MK2 will be used in fully active applications, a wrong setup can destroy your speakers right away.

graph LR
    subgraph Inputs
        A["Input EQ"] --> B["Input Processing"]
        C["ISA"] --> D["Input to Virtual routing"]
    end

    subgraph Virtual Processing
        E["Virtual processing EQ"] --> F["SFX"]
        G["Virtual processing Time Gain"] --> E
    end

    subgraph Outputs
        H["Output processing EQ X/Over"] --> I["Output limiter"]
        J["Output processing Time Gain"] --> I
    end

    style Inputs fill:#f9f,stroke:#333
    style Outputs fill:#bbf,stroke:#333

Operating concept of the VCP

In opposite to previous methods the Virtual Channel Processing (VCP) is a multi-stage signal processing concept that enables the perfect configuration of complex sound systems, opening up completely new possibilities for sound tuning.

The function extends the previous scope of the device by an additional layer of processed channels, which is located between the inputs and outputs. A total of eight additional processed virtual channels and ten processed output channels are available.

This virtual channel layer offers several advantages, especially in complex system configurations.

The main advantages of this concept are:

• Cross-channel group equalizers that affect several output channels simultaneously
• Multi-way speaker configuration of DSP sound effects (SFX)
• Additional features such as Rear Attenuation

– Cross-channel group equalizer

Example application: Active multi-way speaker configuration

If an input signal (e.g. front left) is first routed to a virtual channel (Front L Full) and this signal is then routed to an active multi-way system (e.g. front left – tweeter, midrange and woofer), the group equalizer of the virtual channel will influence all assigned output channels in their tonality. The advantage of this concept is that any amplitude and phase shift of the group equalizer is applied to all channels of the multi-way configuration simultaneously, thus avoiding any negative impact on the interaction of the individual speaker channels.

graph TD
    A["Input A\nFront L Full"] --> B["Virtual A\nFront L Full"]
    B --> C["StageXPander\nLight"]
    B --> D["ClarityXPander\nLight"]
    B --> E["StageEQ\ndeactivated"]
    C --> F["AMP Out A\nFront L High"]
    D --> G["AMP Out C\nFront L Low"]

– Multi-way configuration of the DSP sound effects (SFX)

Example application: 2- or even 3-way center speaker

After activating “Virtual Channel Processing”, the DSP sound effects, such as RealCenter management or Augmented Bass Processing, are also available. These are no longer linked to the outputs but tied to specific “virtual channels”. This makes it possible to route the DSP sound effects to any number of outputs, for example to realize 2- or even 3-way center speaker configurations. There are hardly any limits to flexibility here.

-Additionalfeatures

In addition, the VCP enables the implementation of further new functions. One of these is, for example, the "Rear Attenuation". With the help of a remote control, the volume of the virtual channels "Rear L Full" and "Rear R Full" can be controlled separately. So it is possible even without switching the sound setup, to adjust the volume of the rear speakers (or any other channel, which is routed through these channels).

Configuration of the Virtual Channel Processing (VCP)

To configure the VCP, you first have to enable "Virtual Channel Processing" in the DCM menu of the DSP PC-Tool software. Therefore, go to the "Virtual Channel Processing" tab in the DCM menu and click on the right box with the VCP graphic. Then the configuration will be carried out in two steps. Here's an example of a 3-way configuration with a 2-way input signal.

Workflow step 1 – Input routing

First, the input signals in the various input matrices ("Main to Virtual Routing", "HEC / AUX to Virtual Routing", "Digital to Virtual Routing") need to be routed to the respective virtual channels. This is the same as in normal mode, means that the input signals on the left side are dragged and dropped onto the respective summation matrix. The difference to normal mode is that the names and signal properties of the virtual channels are defined here (Front L Full, Front R Full, Rear L Full, Rear R Full, Front Center Full etc.).

a. First, all input signals must be applied to the respective designated signal types of the virtual channels, means the input with the signal "front left" must be routed to the virtual channel "Front L Full" and so forth.
b. In the case of an adaptation of an OEM active multi-way system, all "front left" signals in this example have to be summed up on the virtual channel "Front L Full" (the input EQ remains effective in the inputs as usual).

Workflow step 2 – Output routing

After all the input signals used in the respective signal routing matrix have been configured, the virtual channels must now be assigned to the physical output channels. Here, a virtual signal (e.g. Front L Full) can be assigned to multiple outputs, such as "front left" tweeter, midrange and woofer. The configuration of these speaker-specific output channels is done in the "Outputs" menu (called "Main" in normal mode) of the DSP PC-Tool. Here you can also configure the channel-specific equalizers, high- and lowpass filters, time alignment, output level and phase settings.

a. In order to assign the virtual channels to the respective output channels the individual virtual signals in the output routing matrix ("Virtual to Output Routing") are dragged and dropped onto the output channels. At this point, the signals typically needn't to be summed, means that each output of this matrix only receives one virtual signal. For example, the output "Front L High" is linked to the virtual signal "Front L Full"; the same is done for the Front L Low".

graph TD
    A["Virtual Inputs"] --> B["[Virtual A"]
Front L Full]
    A --> C["[Virtual B"]
Front R Full]
    A --> D["[Virtual C"]
Rear L Full]
    A --> E["[Virtual D"]
Rear R Full]
    A --> F["[Virtual E"]
Front Center Full]
    A --> G["[Virtual F"]
Rear Fill Full]
    A --> H["[Virtual G"]
Subwoofer1]
    A --> I["[Virtual H"]
Subwoofer2]
    A --> J["[Virtual I"]
Pass Through 1]
    A --> K["[Virtual J"]
Pass Through 2]

    L["DRAG & DROP"] --> M["Man to Virtual Routing"]
    L --> N["REC/AMX to Virtual Routing"]
    L --> O["Digital to Virtual Routing"]
    L --> P["Virtual to Output Routing"]

    M --> Q["Front L Full<br>100.0 %"]
    M --> R["Front R Full<br>100.0 %"]
    M --> S["Front L Full<br>100.0 %"]
    M --> T["Front R Full<br>100.0 %"]
    M --> U["Front R Low<br>100.0 %"]
    M --> V["Front R Low<br>100.0 %"]
    M --> W["Rear L Full<br>100.0 %"]
    M --> X["Rear R Full<br>100.0 %"]
    M --> Y["Front Center Full<br>100.0 %"]
    M --> Z["Front Center Full<br>100.0 %"]
    M --> AA["Subwoofer1<br>100.0 %"]
    M --> AB["Subwoofer2<br>100.0 %"]

    N --> AC["Front L High<br>100.0 %"]
    N --> AD["Front R High<br>100.0 %"]
    N --> AE["Front L Low<br>100.0 %"]
    N --> AF["Front R Low<br>100.0 %"]
    N --> AG["Rear L Full<br>100.0 %"]
    N --> AH["Rear L Full<br>100.0 %"]

    O --> AI["AMP Out A<br>100.0 %"]
    O --> AJ["AMP Out B<br>100.0 %"]
    O --> AK["AMP Out C<br>100.0 %"]
    O --> AL["AMP Out D<br>100.0 %"]

    P --> AM["AMP Out E<br>100.0 %"]
    P --> AN["AMP Out F<br>100.0 %"]

    Q --> AO["AMP Out G<br>100.0 %"]
    Q --> AP["AMP Out H<br>100.0 %"]

    R --> AQ["AMP Out I<br>100.0 %"]
    R --> AR["Line Out I<br>100.0 %"]

    S --> AS["Subwoofer1<br>100.0 %"]
    S --> AT["Subwoofer2<br>100.0 %"]

b. At this point, even a virtual channel in which a DSP sound effect has been activated can be routed to multiple output channels. For example, the "Front Center Full" signal can be assigned to multiple output channels to create an active multi-way center speaker. The corresponding high- and lowpass filters are then configured in the output channels of the "Main" menu.

Configuration of the Virtual Channel Processing (VCP)

Workflow step 3 – Configuration of the virtual channels and notes on the application of the DSP sound effects (SFX)

Now switch to the “Virtual” menu of the DSP PC-Tool. Here you get an overview of the signal flow of the individual channels and the activated sound effects. In addition, it is possible to influence the tonality of all subsequent output channels of a virtual channel at the same time, for example with the help of the equalizer, polarity and other functions.

Notes on the configuration of the DSP sound effects (SFX)

The HELIX V EIGHT DSP MK2 provides unique DSP sound effects such as Augmented Bass Processing, RealCenter, and more when “Virtual Channel Processing” is enabled. In order to enjoy the DSP sound effects, certain settings must be made in the hardware and software configuration.

Note: The DSP sound effects are only available in the V EIGHT DSP MK2 when "Virtual Channel Processing" is enabled. "VCP" can be activated in the DCM menu of the DSP PC-Tool software.

Notes for center processing with its features "RealCenter" and "ClarityXpander"

To be able to use the RealCenter and ClarityXpander function for a center speaker, the following steps must be carried out:

1a. It is necessary to assign an input signal to the virtual channels "Front L Full" and "Front R Full" (see workflow step 1).
1b. In the input routing you have to assign either a sum signal (front left + front right) or an existing center signal to the virtual channel "Front Center Full".

1. Change to the "Virtual to Output Routing" matrix and route the "Virtual E – Front Center Full" channel to the desired output channels (as described in workflow step 2) to which the center processing shall be applied.

For information about input routing see workflow step 1

1. Now switch to the FX menu and activate the desired sound effect in the "Center Processing" tab by setting the appropriate check mark.

For information about output routing see workflow step 2

Notes for front processing with its StageXpander and ClarityXpander features

The StageXpander and Front ClarityXpander settings always affect the virtual channels "Front L Full" and "Front R Full".

Hints for “Augmented Bass Processing” with its “Dynamic Bass Enhancement” and “SubXpander” function

For Augmented Bass Processing certain settings have to be made in order to use it.

1. An input signal has to be assigned to at least one of the virtual subwoofer channels ("Subwoofer 1" or "Subwoofer 2") (see workflow step 1).
2. Change to the "Virtual to Output Routing" matrix and route the channel (s) "Virtual G – Subwoofer 1" and / or "Virtual H – Subwoofer 2" to the desired output channel or channels (as described in workflow step 2) to which the subwoofer signal and its Augmented Bass Processing shall be applied to.
3. Now switch to the FX menu and activate the desired sound effect.

Note: the bass processing is switched on and off together for both "Subwoofer 1" and "Subwoofer 2" channels, nevertheless the two channels still remain separately processed for stereo applications.

ACO platform features

Beside the unique DSP sound effects the V EIGHT DSP MK2 provides a bunch of new system features.

In the DCM menu of the DSP PC-Tool software individual settings can be made for several of these system features.

Turn On & Off Delay

This function allows to determine the delay time with which the integrated DSP is switched on and off. The factory setting is 0.2 seconds. The delay time should only be modified if there are e.g. noises while switching on / off the amplifier.

URC Setup Switch Configuration

The ACO provides ten internal memory locations for sound setups instead of the common two.

By using an optional URC remote control or the Control pushbutton it is possible to toggle between two of the ten memory locations. These two memory locations can be determined in the "URC Setup Switch Configuration". The memory locations one and two are preassigned ex works. To switch between all internal memory locations, the optionally available

DIRECTOR display remote control or the HELIX WIFI CONTROL is recommended.

Remote Output Configuration

This function controls if the remote output (which switches on and off the connected amplifiers) will be temporarily deactivated during a sound setup switch. This function is activated (ON) ex works.

HELIX Extension Card slot (HEC slot)

It is possible to extend the functionality of the HELIX V EIGHT DSP MK2 amplifier by inserting an optional HELIX Extension Card (HEC) – for example a Bluetooth® Audio Streaming module, an additional optical digital input or an USB audio input.

To install a HELIX Extension Card it is necessary to remove the side panel of the V EIGHT DSP MK2 and replace it by the new side panel that comes with the HEC module.

Attention: Install the HEC module only in the designated device and its specific slot. Using the HEC module in other devices or slots can result in damage of the HEC module, the amplifier, the head unit / car radio or other connected devices!

Read in the following the steps how to install a HEC module:

1. First disconnect all cables from the device.
2. Dismantle the side panel where the USB input is located by removing the two Phillips and two Allen screws.
3. Pull out the bottom plate sideways.
4. Prepare the module for installing it into the device. Any further mounting information will be found in the instruction manual of the respective HEC module.
5. Insert the HEC module into the specific slot of the device which is marked in the following picture.

1. Make sure that the HEC module is installed properly and all pins are fully inserted into the socket.

Close-up of electronic circuit board with multiple LED connectors and a green checkmark overlay (no readable text or symbols)

Close-up of a computer motherboard with visible circuitry and a red X mark overlay (no readable text or symbols)

1. Reinsert the bottom plate and fix the new side panel which is delivered with the HEC module with the two Phillips and two Allen screws.
2. Bolt the HEC module to the side panel. Precise mounting information will be found in the instruction manual of the respective HEC module.
3. Reconnect all cables to the device.
4. Turn on the amplifier. The HEC module is automatically detected by the device and the Status LED of the HEC module lights up green.
5. Now you are able to configure the HEC module in the DSP PC-Tool software.

Pure Class GD amplifier technology

Audiotec Fischers proprietary Pure Class GD concept takes the efficiency of conventional Class D amps to the next level. By varying the internal supply voltage depending on the amplifier's input signals, idle losses are significantly reduced and overall efficiency is close to maximum at any time.

So heat dissipation is almost negligible thus allowing smallest heat sinks and most compact form factors. Besides that Pure Class GD amp outperforms conventional Class D designs in terms of sound quality by implementing a fully differential signal path and improved output filter design.

ACO - Advanced 32 Bit CoProcessor

The HELIX V EIGHT DSP MK2 incorporates a extraordinary powerful 32 Bit CoProcessor of the latest generation for all monitoring and communication tasks, both internally and externally. In opposite to the 8 Bit predecessor generation this MCU achieves way higher speeds with respect to setup switching and data communication with our DSP PC-Tool software. A further significant advantage is the integrated, native boot loader of the CoProcessor. It allows software upgrades of all components of the integrated DSP in order to adjust the microcontroller-controlled ADEP.3 circuit for example to future requirements of the diagnostic system of factory radios or if the device will be extended with additional interfaces. In addition, thanks to the new flash memory, the ACO offers 10 memory locations for sound setups instead of the common two.

Smart highlevel input ADEP.3

Modern, factory-installed car radios incorporate sophisticated possibilities of diagnosing the connected speakers. In particular the latest generation of car radios are equipped with additional monitoring functions so that failure messages and loss of specific features (e.g. fader function) quite often appear if an amplifier will be hooked up – but not with the V EIGHT DSP MK2.

The new ADEP.3 circuit (Advanced Diagnostics Error Protection, 3rd Generation) avoids all these problems without loading the speaker outputs of the OE radio during high volumes unnecessarily.

Start-Stop capability

The switched power supply of the HELIX V EIGHT DSP MK2 assures a constant internal supply voltage even if the battery's voltage drops to 6 Volts during engine crank.

Power Save Mode

The Power Save Mode is incorporated in the basic setup. It allows to significantly reduce the power consumption of the amplifiers that are connected to the HELIX V EIGHT DSP MK2 once there's no input signal present for more than 60 seconds. Please note that in many up-to-date cars with "CAN" or any other internal bus structures it may happen that the radio remains "invisibly" turned on for up to 45 min. even after locking and leaving the car! Once the "Power Save Mode" is active the remote output and therefore the connected amplifiers will be turned off. The V EIGHT DSP MK2 will reactivate the remote output within a second if a music signal is applied. It is possible to either modify the turn-off time of 60 sec. or completely deactivate the "Power Save Mode" via the DSP PC-Tool software.

Technical Data

Power RMS ≤ 1% THD+N

- @ 4 Ohms....75 Watts per channel

- @ 2 Ohms ....120 Watts per channel

Max. output power per channel*.....Up to 160 Watts RMS @ 2 Ohms

Amplifier technology ....Pure Class GD

Inputs....6 x RCA / Cinch

8 x Highlevel speaker input

1 x Optical SPDIF (12 - 96 kHz)

1 x Remote In

Input sensitivity....RCA / Cinch max. 4 V or max. 8 V

Highlevel max. 16 V or max. 32 V

Input impedance RCA/ Cinch ....12 kOhms

Input impedance highlevel....9 - 33 Ohms or 20 kOhms

Outputs....8 x Speaker output

2 x RCA / Cinch

2 x Remote Out

Output voltage RCA / Cinch....3 Volts RMS

Frequency response....20 Hz - 22,000 Hz

DSP resolution....64 Bit

DSP power 295 MHz (1.2 billion MAC operations/second)

Sampling rate 48 kHz

DSP type ......Audio signal processor

Signal converters....A/D: AKM 32 Bit

D/A: AKM 32 Bit

Signal-to-noise ratio digital input 107 dB (A-weighted)

Signal-to-noise ratio analog input....102 dB (A-weighted)

Distortion (THD)....< 0.015 %

Damping factor ....> 70

Operating voltage 10.5 - 16 Volt (max. 5 sec. down to 6 Volts)

Idle current....540 mA

Max. remote output voltage....500 mA

Fuse....2 x 30 A LP-Mini-Fuse (APS)

Additional features....HEC slot, ADEP.3 circuit, Control Input, 32 Bit

CoProcessor, Auto Remote switch

Dimensions (H x W x D) 44 x 220 x 180 mm / 1.73 x 8.66 x 7.09"

* In typical multi-channel applications (2- / 3-way system + rear + subwoofer)

Warranty Disclaimer

The limited warranty comply with legal regulations.

Failures or damages caused by overload or improper use are not covered by the warranty. Please return the defective product only with a valid proof of purchase and a detailed malfunction description. Technical specifications are subject to change!

Errors are reserved! For damages on the vehicle and the device, caused by handling errors of the device, we can't assume liability. This product is tagged with a CE-Certifikation mark. Thereby these devices are certified for the use in vehicles within the European Community (EC).

Note:

"The Bluetooth® word mark and logos are registered trademarks owned by Bluetooth SIG, Inc. and any use of such marks by Audiotec Fischer GmbH is under license. Other trademarks and trade names are those of their respective owners."

AUDIOTEC

FISCHER