The HELIX FAQ

Questions and answers about our HELIX products.

1. Does it make sense to combine only amplifiers and speakers of a device series (e.g. P series)?

It goes without saying that you can easily combine all products with one another. Your choices are only limited by your budget and requirements. Of course, you should ensure that your choices are well informed.

2. Why do most HELIX subwoofers have an impedance of 2 x 2 Ohms?

The dual voice coil configuration increases the flexibility in designing the sound system. As a result, the subwoofer can be controlled in three different ways and thus get the maximum power from almost every amplifier. This means that both 1 x 4 Ohms (both voice coils connected in series) and 1 x 1 Ohms (both voice coils connected in parallel) configurations are possible if only one amplifier channel is available. If you have two, then the separate control of both voice coils is the best solution (e.g. in conjunction with the P TWO or P SIX DSP).

3. Are there problems with the speaker diagnostics and detection by my original car radio when I am driving a HELIX amplifier through the highlevel inputs?

In recent years, we have optimized the input circuit of our amplifiers to prevent this. The loudspeaker diagnostics in almost all factory installed radios is now very complex, so it must already present some resistance in the amplifier to avoid entries in the fault memory of the vehicle. Audiotec's proprietary circuits "ADEP" and "ADEP-SB" are unique in this regard and have a good track record of avoiding speaker detection problems.

4. Is a separate signal processor (DSP) better than a solution integrated into the amplifier?

The decision depends solely on the desired configuration. If an amplifier such as the P SIX DSP or the V EIGHT DSP meets all the requirements for your installation in one device, there is no reason to choose one of our separate DSPs for use with a dedicated amplifier. If the number of channels required or the desired output power cannot be achieved with the integrated solutions, then the separate configuration is the best path forward. 
All HELIX DSP products use only the highest-performance processors (DSPs) of the latest generation with 64 Bit resolution.

5. Do you absolutely need a DSP in a sound system or is it synonymous without?

Those who want to get the most out of the existing speakers will look to use a signal processor (DSP) - whether integrated into the amplifier or as a separate component.
Of course, the active crossover in our amplifiers that do not include a DSP still result in a great sound, but a DSP has quite a different way of influencing sound due to its enormous range of functions.

6. Can I use a HEC module in a different Audiotec Fischer product?

The HEC / MEC modules for the individual products differ by the side plate supplied. If you do not have the right side plate, then the installation of the HEC module is not going to be possible. We therefore highly recommend that you only use the HEC / MEC module that is designed and packaged for the respective device.

7. My power amps make an on and off noise since I installed a HELIX signal processor in front of it. What could be the reason?

In your current setup, the power amplifiers have been switched on via the remote signal of the car radio, this task must now be controlled by the DSP to avoid On/Off noise. The car radio activates the DSP via the "Remote In" or the highlevel inputs and the DSP controls the downstream power amplifiers via its "Remote Out". In the DSP PC-Tool software, the times for switch-on and switch-off delay can be adjusted individually depending on the amplifier being used.

8. The USB cable for connecting the DSP to the PC that is included with the device is too short. Can I just extend it with an appropriate USB cable?

In such cases we recommend using a powered USB extension cable (with integrated amplifier), as this is the only way to ensure stable communication between the PC and the HELIX component.

9. I have had generator noise ("alternator whine") since installing a DSP between the radio and amplifier.

Our signal processors (DSPs) have a ground switch, you can use this to galvanically isolate the signal inputs from the signal outputs. Depending on the vehicle, these must be separated or connected via a 200 Ohm resistor. The best results are achieved with trial and error.

10. Can you use the wired remote control URC.3 and the display remote control DIRECTOR simultaneously on one device?

This is not possible because both remote control versions use the same connector on the device for input. All our devices only have a single DIN port.

11. How do I set the input sensitivity (gain) of my amplifier or signal processor correctly?

For optimum signal-to-noise ratio, it is important that the input sensitivity of an amplifier or signal processor be matched to the output voltage of the signal source.
For example, if the signal source supplies a maximum output voltage of 4 Volts, the input of the connected device should be set to the same 4 Volts value. Too often it happens that amplifiers are set much too "sensitive" (eg 1 - 2 Volts), because it can result in a higher volume.
In actuality, you will only increase the risk of noise and other distortions becoming audible if not correctly calibrated.

12. What happens if I use too thin cables to power my amplifiers?

The right cable cross-section (gage) in relation to the cable length is enormously important, this is because the battery voltage at the amplifier will not be stable under load.
If the amplifier has no regulated power supply, the best case scenario is that its output power of the amplifier is reduced. If the amplifier has a power supply control function, the effect is much worse as it will attempt to equalize the fluctuations of the on-board voltages.
A large voltage drop across the power supply line will result in the amp attempting to compensate for this by drawing a larger current, which in turn leads to an even greater voltage drop in the power supply line. This "vicious circle” results in the amplifier producing significantly more heat than necessary.
The worst case scenario is that the power cable will get hot enough to melt the insulation around it and will allow for the cable to come into direct contact with the cars metal body, which is used to ground the battery and other equipment. This presents a serious risk of the battery exploding and the car catching fire. Therefore, it is strongly recommended to adhere to the required cable cross-sections in the instruction manual of the respective amplifier, while accounting for additional equipment that might also be connected.

1. DIRECTOR does not turn on

Possible reason: No power supply - wires are not correctly connected / no turn-on signal from DSP.
Trouble-shooting: Check the cable plugs for proper mounting / Check the supply and remote voltage of the DSP.

2. DIRECTOR does load the Demo mode while DSP is connected properly

Possible reason: No DSP detected/recognized.
Trouble-shooting: Check the cable plugs for proper mounting / Check compatibility of the DSP.

3. No sound after connecting the DIRECTOR

Possible reason: Volume in the DIRECTOR is set too low / Mute activated / wrong input source selected.
Trouble-shooting: Check volume controls (Master, HEC/MEC/AUX, Digital Optical Volume) - in some cases you have to reassign the soft keys to access all volume screens; deactivate mute (check mute symbol); switch between the signal sources in the Input Select screen.

4. No connection to compatible device possible

Possible reason: Transmission problem to DSP / incompatible software version.
Trouble-shooting: Check the cable plugs for proper mounting / Check for DSP PC-Tool updates and install the latest version on your DSP / Check for DIRECTOR firmware updates and make an update via the DIRECTOR Updater.

5. DIRECTOR does not turn on after DIRECTOR update and the screen stays black

Possible reason: Update failed / DIRECTOR stays in update mode and the screen stays black until the update is successfully completed.
Trouble-shooting: Try to update the DIRECTOR again / Check the USB cable to DIRECTOR and try to replace it with a new cable (short and high quality) / Try the update with a different computer.

6. Connection with the DSP PC-Tool not possible

Possible reason: Communication / transmission issues.
Trouble-shooting: Use only the USB port on the DIRECTOR / Check the cable plugs for proper mounting / Check the USB cable to DIRECTOR and try to replace it with a new cable (short and high quality) / Try a different computer.