M ONE - Receiver Audiotec Fischer - Free user manual and instructions

USER MANUAL M ONE Audiotec Fischer

Abstract geometric logo with a stylized human figure and a triangular shape (no text or symbols)

HELIX

HELIX PTWO MADE IN GERMANY

P TWO

2-channel High-Res amplifier with integrated active

crossover and digital signal input

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

The HELIX P TWO highlights best quality, excellent manufacturing and state-of-the-art technology.

Thanks to more than 30 years of experience in research and development of audio products this amplifier generation sets new standards. We wish you many hours of enjoyment with your new HELIX amplifier.

Yours,

AUDIOTEC FISCHER Team

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 P TWO 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 ensure 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 P TWO amplifier

The HELIX P TWO 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 the HELIX P TWO. The fuses may only be replaced by identically rated fuses (3 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 vehicle harnesses.

Connectors and control units

1 2 3 5 6 7 8 9 10 11 12 4

① Highlevel Input

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

② Line Input

RCA inputs for connecting lowlevel line signals.

③ Clipping LED

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

④ Gain

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

⑤ Remote Control

Input for connecting the included cable remote control for volume adjustment.

⑥ HPF Frequency

Control for adjusting the highpass filter from 15 Hz bis 4,000 Hz.

⑦ X-Over

Switch for activating the filters for channel A and B.

⑧ LPF Frequency

Control for adjusting the lowpass filter from 15 Hz bis 4,000 Hz.

⑨ Bass Boost Frequency

Control for adjusting the center frequency of the bass boost from 40 Hz bis 120 Hz.

10 Bass Boost Gain

Control for adjusting the bass boost from 0 to 9 dB.

11 Input Mode

Switch to route input signals to respective amplifier channels.

12 Optical Input

Optical input for digital stereo signals (SPDIF format).

OUTPUT CHANNELS 13 15 16 17 18

13 Output Channels

Speaker outputs for connecting speaker systems.

14 Fuse LED

This LED indicates the operating mode of the amplifier.

15 GND

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

16 REM

Connector for the remote cable.

⑰ +12 V

Connector for the +12 V power cable of the positive terminal of the battery.

18 Auto Remote

This switch allows to activate / deactivate the automatic turn-on feature via the highlevel inputs of the amplifier.

① Highlevel Input

2-channel highlevel loudspeaker input to connect the amplifier directly to the loudspeaker outputs of OEM / aftermarket radios that do not have any low-level line outputs. The Highlevel Input is equipped with our proprietary ADEP circuit (Advanced Diagnostics Error Protection) which ensures that the car radio detects the amplifier as a speaker and thus neither any function of the radio (e.g. fader) will be deactivated nor any error log in the CPU of the car will be created. If this input is used the remote input (REM) does not need to be connected as the amplifier will automatically turn on once a loudspeaker signal is applied.

Attention: Solely use the pluggable screw-terminal for the highlevel connector which is included in delivery!

Important: It is strictly forbidden to use the High-level 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.

② Line Input

2-channel lowlevel line input to connect signal sourc es such as head units / radios / DSPs.

Important: It is strictly forbidden to use the High-level 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.

③ Clipping LED

This LED lights up red if one of the Highlevel Inputs, lowlevel Line Inputs or the Optical Input is overdriven. If this LED lights up reduce the input sensitivity by using the control 4 (Gain) until the LED goes out.

④ Gain

This control is used to adapt the input sensitivity 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 lowlevel Line Input is 2 - 8 Volts, 5 - 20 Volts for the Highlevel Input and 0 - 12 dB for the Optical Input.

If the Highlevel Input is used in combination with a standard car radio we recommend an input sensitivity of roughly 9 Volts. For this purpose, turn the control from max. CCW position to 9 o'clock position.

⑤ Remote

This input is used to connect the included remote control. The remote control allows you to control the volume of the amplifier.

Note: Volume control via remote control is only activated in bandpass mode.

⑥ HPF Frequency

This control is used to adjust the crossover frequency of the highpass filter from 15 Hz to 4,000 Hz. This control is activated if the X-Over switch is set to HPF (highpass filter) or BPF (band-pass) and its adjustment is mandatory.

⑦ X-Over

This switch allows to set the internal crossover to highpass, fullrange or bandpass mode.

If the X-Over switch is set to HPF (highpass filter) the crossover frequency for the highpass can be adjusted with control 6. At switch position FULL (full-range) the crossover is bypassed.

At switch position BPF (lowpass filter) the highpass is always active. That means a bandpass is created in any case.

By adjusting the highpass (control 6) and lowpass (control 8) filter any bandpass between 15 Hz and 4,000 Hz can be realized.

Caution: To avoid a loss of gain make sure that the crossover frequencies of the high- and lowpass filters do have an interval of at least two octaves when generating a bandpass.

That means if the lowpass signal is adjusted to 320 Hz the highpass should be adjusted to 80 Hz or less (one octave = doubled frequency or halved frequency). If a subwoofer is connected we recommend to use the highpass control (control 6) as variable subsonic / low-frequency highpass filter or turn it counterclockwise to 15 Hz to get a subsonic filter.

⑧ LPF Frequency

This control is used to adjust the crossover frequency of the lowpass filter from 15 Hz to 4,000 Hz.

⑨ Bass Boost Frequency

This control is used to adjust the center frequency of the bass boost from 40 Hz to 120 Hz. The adjusted bass frequency can be enhanced from 0 to 9 dB with control 10. This is useful to emphasize or correct a determined frequency range of the subwoofer or kickbass.

⑩ Bass Boost Gain

This control is used to increase the adjusted bass center frequency (see item 9, Bass Boost Frequency) from 0 to 9 dB.

⑪ Input Mode

This switch is used to route the input signals to the respective amplifier channels.

Stereo: If the head unit / car radio provides one stereo output, both speaker outputs are supplied with the corresponding input signal.

Stereo Summed: In this mode a sum signal is generated by the input signals of the channels A and B. Mono: If only the Line Input or Highlevel Input of channel A is connected, both amplifier channels are supplied with this signal. In this mode the input signal of channel A is routed to channel B. Please consider that the balance control of the head unit / car radio has the same effect on channel B as on channel A.

Note: The Optical Input always provides a stereo signal. When this signal input will be used please choose switch position "Stereo" or "Stereo Summed", depending on the application.

⑫ 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 28 and 96 kHz. Thanks to the SPDIF Direct In switch the input stage of the P TWO can be bypassed and allows to directly route the signal from the integrated DA converter to the internal power stage. For this purpose, you have to open the device and change the position of the SPDIF Direct In switch to "On" as well as the position of the X-Over switch to "Full" (see page 17, item SPDIF Direct In switch).

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 P TWO. This may cause severe damage to your speakers. We strong-

ly recommend to only use volume controlled audio sources!

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

Note: It is possible to use the Optical Input and the Highlevel Input or lowlevel Line Input at the same time.

⑬ Output Channels

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

⑭ Fuse LED

The Fuse LED indicates the operating mode of the amplifier.

Green: The amplifier is ready for operation.

Red: A malfunction has occurred that may have different root causes. The HELIX P TWO is equipped with protection circuits against over- and undervoltage, short-circuit on loudspeakers and reverse connection. Please check for connecting failures such as short-circuits or other wrong connections. If the amplifier does not turn on after that it is defective and has to be sent to your local authorized dealer for repair service.

Flashing red: The amplifier is overheated. The internal temperature protection shuts down the device until it reaches a safe temperature level again.

Flashing red / green: The fuses inside the device are destroyed. Please check the fuses and, if necessary, replace them. They may only be replaced by identically rated fuses (3 x 30 Ampere) to avoid damage of the amplifier.

15 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.

⑯ REM

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 / car radio is switched on. Thus the amplifier is switched on and off together with the head unit / car radio. This input needn't to be assigned if the Highlevel Input is used.

⑰ +12 V

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

⑱ Auto Remote

The P TWO will be turned on automatically if the Highlevel Input is used or if a signal is applied to the remote input (REM) terminal. The Auto Remote switch allows to activate / deactivate the automatic turn-on feature. The feature should be deactivated if there are e.g. disturbing noises while switching on/off the amplifier.

Note: If the automatic turn-on function is deactivated it is mandatory to use the remote input to power up the amplifier! An automatic turn-on via the high-level signal is then no longer possible.

SPDIF Direct In switch

Due to the SPDIF Direct In switch inside the device, the input stage of the P TWO can be bypassed and the input signal of the Optical Input directly routed from the integrated DA converter to the internal power stage. To activate the direct signal routing you have to open the device and change the position of the SPDIF Direct In switch. Therefore remove the ten Allen head screws of the bottom plate to get access to the switch. It is located near by the “Made in Germany” imprint (see marking in the following picture).

R1587 1V-0 2417 C MADE IN GERMANY NUTRIEN GOMES UNTRENDRA

Initial start-up and functions

On: Input stage is bypassed.

Off: Input stage is not bypassed (ex works).

Note: This switch only affects the signal routing of the Optical Input.

Note: The amplifier must be operated in fullrange mode for routing the digital input signal directly to

the power stage. Therefore change the position of the X-Over switch to „Full“ (see page 15, item 7; X-Over).

Note: If the switch is set to "On" position the High-level and lowlevel Line Input as well as the Gain control (4) are without function!

Installation

Connection of HELIX P TWO 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 13). It is recommended that this unit will be installed by an authorized HELIX dealer.

1. Connecting the lowlevel line inputs

Use the correct cable (RCA / Cinch cable) to connect these inputs to the lowlevel line outputs of your car radio. It is not mandatory to use both lowlevel line inputs. If only one channel will be connected we recommend to use channel A and set the Input Mode switch to "Mono". When both channels will be used please choose switch position "Stereo" or "Stereo Summed", depending on the application (see page 16, item 11; Input Mode). The automatic turn-on circuit does not work when using the lowlevel line inputs (Line Input) or the digital input (Optical Input). In this case the remote input (REM) has to be connected to activate the HELIX P TWO.

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 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 (Highlevel Input) can be connected directly to the loud-

speaker 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:

$$ \text { Channel } A = \text { Left } $$

$$ \text { Channel } B = \text { Right } $$

Actually it is not mandatory to use all highlevel speaker inputs. If one channel will be connected we recommend to use channel A and set the Input Mode switch to "Mono". When both channels will be used please choose switch position "Stereo" or "Stereo Summed", depending on the application (see page 16, item 11; Input Mode). Make sure that the polarity is correct. If one connection has reversed polarity it may affect the performance of the amplifier. If this input is used the remote input (REM) does not need to be connected as the amplifier will automatically turn on once a loudspeaker signal is applied.

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.

The automatic turn-on circuit does not work when the digital input is used. Therefore it is mandatory to connect the remote input (REM). Due to the fact that the Optical Input always provides a stereo signal, the Input Mode switch has to be set to "Stereo" or "Stereo Summed", depending on the application (see page 16, item 11; Input Mode).

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 P TWO. This may cause severe damage to

your speakers. We strongly recommend to only use volume controlled audio sources!

Information: The P TWO can only handle uncompressed digital stereo signals in PCM format with a sample rate between 28 kHz and 96 kHz and no MP3- or Dolby-coded signals.

4. Configuration of the digital signal input (optionally)

If a digital signal source is used you have the possibility to route the digital signal directly and loss-free from the integrated DA converter to the internal power amplifiers. To activate the direct signal routing you have to change the position of the SPDIF Direct In switch to "On" (see page 17, item SPDIF Direct In switch) as well as the position of the X-Over switch to "Full" (see page 15, item 7; X-Over).

Note: The switch only affects the signal routing of the Optical Input.

5. Adjustment of the input sensitivity

Attention: It is mandatory to properly adapt the input sensitivity of the P TWO to the signal source in order to avoid damage to the amplifier.

If you want to change the input sensitivity use the control 4 (see page 15, item 4; Gain). The setting of the control affects the lowlevel (Line Input) and highlevel speaker inputs (Highlevel Input) as well as the digital signal input (Optical Input)!

Follow the subsequent steps if you like to perfectly adapt the amplifiers input sensitivity to your audio source by using the control:

1. Don't connect any loudspeakers to the outputs of the P TWO during this setup.
2. Turn on the amplifier.
3. Adjust the volume of your head unit / car radio / digital signal source to approx. 90 % of the max. volume and playback an 1 kHz full scale test tone (0 dB).
4. If the Clipping LED already lights up, you have to reduce the input sensitivity via control (page 15, item 4; Gain) 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.

If the Highlevel Input is used in combination with a standard car radio we recommend an input sensitivity of roughly 9 Volts. For this purpose, turn the control from max. CCW position to 9 o'clock position.

6. Connection to power supply

Make sure to disconnect the battery before installing the HELIX P TWO!

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 (P TWO = max. 90 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.

7. Connecting the remote input

The remote input (REM) has to be connected to the radio remote output if the amplifiers digital input or lowlevel line inputs is/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.

8. Configuration of the remote input

The P TWO will be turned on automatically if the highlevel inputs are used or if a signal is applied to the remote input terminal. The Auto Remote switch (see page 17, item 18; Auto Remote) allows to deactivate the automatic turn-on feature. The feature should be deactivated if

Installation

there are e.g. noises while switching on/off the amplifier.

Note: If the automatic turn-on function is deactivated it is mandatory to use the remote input terminal to power up the amplifier! The highlevel signal will be ignored in this case. To deactivate the automatic turn-on feature you have to change the position of the Auto Remote switch to "Off".

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 to 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 positive terminal is indicated on most speakers. The impedance of each channel must not be less than 2 Ohms, otherwise the amplifier protection will be activated. In addition the speaker outputs can neither be bridged nor connected in parallel!

Examples for speaker configurations can be found on page 21.

Unique Features of the HELIX P TWO

Ultra HD Class D amplifier technology

Compared to conventional Class D amps, this concept achieves an extended frequency response to more than 40 kHz in combination with reduced distortion thanks to an advanced integrated feedback design. Ultra HD Class D achieves outstanding, "Class AB-like" sound quality combined with the efficiency of a Class D amplifier.

Signal converters with a native resolution of 32 Bit

The HELIX P TWO uses for the optical input a high-class DA signal converter of the latest generation with a native resolution of 32 Bit instead of the common 24 Bit. The result is an unprecedented precision in signal conversion that especially optimizes the sound quality at lower signal levels.

Smart highlevel input

The latest generation of OE car radios incorporates sophisticated possibilities of diagnosing the connected speakers. If a common amplifier will be hooked up failure messages and loss of specific features (e.g. fader function) quite often appears - but not with the P TWO.

The new ADEP circuit (Advanced Diagnostics Error Protection) 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 P TWO assures operation even if the battery's voltage drops down to 6 Volts during engine crank.

Examples for speaker configurations

2-channel fullrange application
Component system

INPUT CHANNEL RightLeft Highpass filter X-OVER HPF FULL BPF HPF HPF FREQ 50 - 100 Hz

2-channel subwoofer application
Subwoofer with dual voice coil
Bandpass

OUTPUT CHANNELS VC 1 + - + - VC 2

VC = Voice coil

BPF

Highpass filter ca. 15 Hz

Lowpass filter ca. 80 Hz

2-channel subwoofer application in combination with HELIX P SIX DSP MK2 incl. HEC module

Subwoofer with dual voice coil

Black electronic device with multiple ports and mounting holes (no visible text or symbols)

Outputs

Optical Out
The connection of the two amplifiers is made by a digital audio cable.

Remote Out

Inputs

Optical Input

REM

P TWOP SIX DSP MK2

Black electronic device with heat sink and ventilation slots (no visible text or symbols)

OUTPUT CHANNELS VC 1 + - + - VC 2

VC = Voice coil

The crossover frequency for the high- and lowpass will be adjusted in the P SIX DSP MK2 by using the DSP PC-Tool Software. To deactivate the filters of the P TWO set the X-Over switch to "FULL" and the SPDIF Direct In switch to "ON".

Technical Data

Output power RMS / max.

- @ 4 Ohms....2 x 280 / 560 Watts

- @ 2 Ohms....2 x 490 / 980 Watts

Amplifier technology ....Ultra HD Class D

Inputs....2 x RCA / Cinch

2 x Highlevel speaker input

1 x Optical SPDIF (28 - 96 kHz)

1 x Remote In

1 x Remote control input

Outputs....2 x Speaker output

Signal converter for optical input ....BurrBrown 32 Bit DA converter

Frequency response....10 Hz - 40,000 Hz

Bass boost....0 - 9 dB / 40 Hz - 120 Hz

Highpass....15 Hz - 4,000 Hz adjustable

Lowpass 15 Hz - 4,000 Hz adjustable

Bandpass....15 Hz - 4,000 Hz adjustable

Slope high- / lowpass ....Butterworth 12 dB/Oct.

Distortion (THD)....< 0.005 %

Signal-to-noise ratio....105 dB (A-weighted)

Input sensitivity....Highlevel 5 - 20 Volts

RCA / Cinch 2 - 8 Volts

Damping factor ....> 200

Input impedance RCA / Cinch ....10 kOhms

Input impedance highlevel....13 Ohms

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

Fuse....3 x 30 A LP-Mini-fuse (APS)

Dimensions (H x W x D)....50 x 260 x 190 mm / 1.97 x 10.24 x 7.48"

Additional features....Active, adjustable crossover, bass boost, input mode switch, highlevel input with Advanced Diagnostics Error Protection (ADEP), Auto Remote switch, SPDIF Direct In switch, cable remote control for volume adjustment

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. These devices are certified for the use in vehicles within the European Community (EC).

AUDIOTEC

FISCHER