Pro-Ject Pre Box DS2 Digital
Instructions for Use
Dear music lover, thank you for purchasing this Pro-Ject Audio Systems preamplifier. In order to achieve maximum performance and reliability you should study these instructions for use carefully.
Important notice: Warning of a hazard for the user, the unit or possible misuse.
Safety Instructions
AC outlet voltages vary from country to country. Before connecting to the mains, make sure that the voltage in your area meets the voltage requirements printed on the power supply.
The power supply is used to disconnect the unit from the mains. Make sure that the power supply is easily accessible at all times. Never handle the device or the power supply while your hands are wet or damp.
Avoid letting liquids enter the device or the power supply. Never place any item containing liquid, such as a flower vase on or near the device. Never spill any liquid on the device or the power supply.
Never place any naked flame sources, such as lighted candles on or near the device. The product shall not be used in damp or wet locations, next to a bathtub, sink, swimming pool or any other similar conditions.
Connectors
Make all connections whilst the preamplifier is disconnected from the power supply.
Take care to connect the left and right channels correctly. The right channel is usually marked red, the left channel black or white.
Never use any other power supply than the one supplied with the unit except of Pro-Ject Power Boxes which can replace original power supplies.
Rear Panel Connectors:
The rear panel features the following connectors:
- USB: For connection to a computer.
- In 1: Analogue input.
- In 2, In 3: Optical S/PDIF digital inputs.
- In 4: Coaxial S/PDIF digital input.
- BT In 5: Bluetooth antenna connector.
- Trigger Input: 12V trigger input (2.5mm socket).
- Trigger Output: 12V trigger output (2.5mm socket).
- Fix Out: Fixed analogue RCA output.
- Var Out: Variable analogue RCA output, controlled by the volume knob.
- Sub Out: Subwoofer connection (RCA).
- Var Gain: DIP switch for +6dB gain on Variable Out.
- Power 18V: DC power input.
- CE / RoHS markings.
Analogue Out
The unit offers the following analogue RCA output sockets:
- Fix Out: Fixed output level.
- Var Out: Variable output level controlled by the Volume knob on the front panel. Gain of the output can be increased by 6dB using the DIP switch Var Gain.
- Sub Out: Subwoofer connection.
Headphone: Socket on the front panel.
Inputs
In1 USB
Dedicated to connection to a Computer. Connect the USB-input of the unit to a free USB-socket on your computer. Ensure the unit is powered on.
Driver Installation (Windows® Operating Systems Only)
A USB driver, supplied on CD, must be installed for Windows® operating systems. Insert the CD and follow the instructions. Restart the computer after installation.
Settings Check/Configuration (e.g., Windows 7® and newer):
- Control Panel → Hardware and Sound → Sound → Playback: Select "Speaker/Project Pre Box DS2 USB 2.0 Audio Out".
- Properties → Supported formats: Ensure nothing is assigned.
- Level → Sound: Set to 100.
- Enhancements: Disable all enhancements.
- Advanced → Default Format: Set to "studio quality 24/192".
Note: Connect directly to a computer's USB-socket. Connecting to USB-hubs or switches can cause problems.
In 2 to In 4: Digital S/PDIF Inputs
The Pre Box DS2 Digital offers three digital S/PDIF inputs: In 2 and In 3 are optical inputs, and In 4 is a coaxial input.
In 5: Bluetooth Connection
Ensure the antenna is attached to the BT In 5 connector on the back panel before using Bluetooth.
The LED for Input 5 BT indicates the status:
- Slow blinking: No active Bluetooth connection.
- Fast blinking: Waiting for pairing confirmation.
- Steady light: Bluetooth device is connected.
Connection of a new device is only possible when the LED is blinking slowly.
Pairing with Android Devices
Open Settings, tap Bluetooth, turn on Bluetooth, and tap Scan. Searched devices will appear. Tap "Pre Box DS2 Digital" and confirm the pairing code on your Android device. Then, press the Subsonic button (or button 8 on the remote) on the Pre Box DS2 Digital when the blue LED of input 5 blinks fast. Upon pairing, your Android device will show "Connected to media Audio". You can then play music from your Android device via Bluetooth.
Bluetooth Pairing with Apple Devices
Tap Settings, tap Bluetooth, turn on Bluetooth. Your device will automatically search for available devices. Tap "Pre Box DS2 Digital" and confirm by pressing the Subsonic button (or button 8 on the remote) when the blue LED of input 5 blinks fast. Upon pairing, your Apple device will show "Connected to media Audio".
Line In 6: Analogue Input
This input is for sources with an analogue output signal, such as tape decks or FM tuners.
Phono In 7: Phono Input
Connect the tonearm signal lead to the Phono In 7 input. The MM/MC switch on the front panel allows adaptation to the connected cartridge type. The earthing wire may be connected to the screw terminal if hum problems are encountered when using a turntable.
Mains Power Connection and Methods to Switch the Unit On and Off
Connect the low voltage plug from the power supply to the Power 18V socket of the preamplifier before connecting the power supply to the mains. The unit can be switched on and off using two methods, which have equal priority.
It is recommended to set the volume control to minimum before switching on.
1. Using Front Pushbutton to Switch On or Into Standby
The pushbutton on the front panel alternately turns the power on or returns it to standby mode. The blue LED on the front panel indicates that the unit is powered on. If a trigger signal is present, the unit cannot be switched off by the pushbutton.
2. Remote Power On - Triggers
The unit can be switched on via other Box Design components when a 12V trigger voltage is present at the 2.5mm socket marked "Trigger Input". Special power-on cables (polarity ⏚+) are available as accessories. The remote power-on signal can be relayed to further units via the "Trigger Output" socket. When the 12V trigger signal is switched off, the unit will also switch off.
Warning: Trigger cables may only be plugged into the sockets when the unit is disconnected from the power supply and the mains. Failure to do so may result in damage to the unit.
Remote Control
POWER: Turns the unit on or back into standby.
MUTE: Activates and deactivates mute. If mute is engaged, the blue LED above the ON/OFF switch flashes.
CH+/CH-: Select the inputs in turn.
Buttons 1-7: Access a specific input directly.
Button 8: Confirms Bluetooth pairing.
Front Panel Controls
Headphone Connection
Connect headphones to the 6.3mm jack socket on the front panel. The rear outputs are not disconnected when headphones are in use.
Volume
Adjust the volume to the desired level using the large knob in the middle of the front panel.
Input Selector
After the unit is powered on, operate the buttons marked with ◀ and ▶ to select inputs. The selected input will be shown by the corresponding LED.
Subsonic
This button activates or deactivates the subsonic filter. The blue LED is on when the subsonic filter is active.
MM MC
This button selects between MM and MC cartridge types.
Sound Mode
Mode 1: Upsampling
This mode upsamples all incoming signals to the highest possible output rate.
| Input | Input PCM Sampling Rate [kHz] | Output PCM Sampling Rate [kHz] | Available Filters |
|---|---|---|---|
| USB | 44 | 705 | 1,2 |
| 48 | 768 | 1,2 | |
| 88 | 705 | 1,2 | |
| 96 | 768 | 1,2 | |
| 176 | 705 | 1,2,3,4 | |
| 192 | 768 | 1,2,3,4 | |
| 352 | 705 | 1,2,3,4 | |
| 384 | 768 | 1,2,3,4 | |
| 705 | 705 | 1,2,3,4 | |
| 768 | 768 | 1,2,3,4 | |
| S/PDIF | 44 | 768 | 1,2 |
| 48 | 705 | 1,2 | |
| 88 | 768 | 1,2 | |
| 96 | 705 | 1,2 | |
| 176 | 768 | 1,2,3,4 | |
| 192 | 705 | 1,2,3,4 | |
| USB DSD | Input DSD | Output DSD | Available Filters |
| 64 | 256 | 1,2,3,4 | |
| 128 | 256 | 1,2,3,4 | |
| 256 | 256 | 1,2,3,4 |
Mode 2: Conversion to DSD
All incoming signals are converted to DSD format.
| Input | Input PCM Sampling Rate [kHz] | Output DSD | Available Filters |
|---|---|---|---|
| USB | 44-48 | 128 | 1,2 |
| 88-96 | 256 | 1,2 | |
| 176-768 | 256 | 1,2,3,4 | |
| S/PDIF | 44, 48, 88 | 128 | 1,2 |
| 176 | 128 | 1,2,3,4 | |
| 96 | 256 | 1,2 | |
| 192 | 256 | 1,2,3,4 | |
| USB DSD | Same as with Sound Mode 1 | ||
Mode 3: USB Upsampling Bypass
USB input sampling rate remains the same as USB output sampling rate.
| USB Input Sample Rate [kHz] | Available Filters |
|---|---|
| 44-96 | 1,2,3,4 |
| 176-768 | 1,2,3,4,5 |
DSD input format remains the same as DSD output format.
S/PDIF input rates are upsampled to PCM352kHz / PCM384kHz.
| Input | Input PCM Sampling Rate [kHz] | Output PCM Sampling Rate [kHz] | Available Filters |
|---|---|---|---|
| S/PDIF | 44 | 384 | 1,2 |
| 48 | 352 | 1,2 | |
| 88 | 384 | 1,2 | |
| 96 | 352 | 1,2 | |
| 176 | 384 | 1,2,3,4 | |
| 192 | 352 | 1,2,3,4 |
Filters
The Filter button toggles between 5 filters. Availability of filters depends on input format and frequency.
| Filter | Sound Type | Filter Name | Remarks | Sound Source Positioning | Edge Positioning |
|---|---|---|---|---|---|
| 1 | Natural tone | Super slow roll-off | No echo, natural sound | Close | Ultra sharp |
| 2 | Acoustic tone | Short delay roll-off | Minimal echo, original sound | Sharp | |
| 3 | Traditional tone | Slow roll-off | Minimal echo, original sound | Middle | |
| 4 | Acoustic sound | Short delay sharp roll-off | Post echo, bass sound | Sharp | |
| 5 | Traditional sound | Sharp roll-off | Pre and post echo, powerful sound | Far | Slow |
DSD Playback Setup with Foobar2000
DSD playback on a computer using Windows® is reliably possible with the PC software player Foobar2000. The player requires preparation to play DSD files.
Required Software and Drivers:
- Foobar2000: http://www.foobar2000.org/download
- Foobar2000 ASIO Playback Component: http://www.foobar2000.org/components/view/foo_out_asio
- Foobar2000 SACD Playback Component: http://sourceforge.net/projects/sacddecoder/files/foo_input_sacd/
Unzip the downloaded files and store them in a folder. Install the USB driver (provided on CD) first by running Setup.exe. Then, install Foobar2000.
Integrating Components into Foobar2000:
1. Open Foobar2000. Navigate to File → Preferences.
2. In the Preferences window, click on "Components".
3. Click "Install..." and locate the "foo_out_asio.fb2k-component" file. Select it and click "Apply". Confirm the restart prompt with "Yes".
4. Exit Foobar2000. Run "ASIOProxyInstall-0.6.5.exe" from the "foo_input_sacd" folder. Follow the installation prompts.
5. Restart Foobar2000. Go to File → Preferences again.
6. Click "Install..." and locate the "foo_input_sacd.fb2k-component" file. Select it and click "Apply". Confirm the restart prompt with "Yes".
Configuring Output Settings:
1. In the Preferences window, navigate to Playback → Output.
2. Under "Device", select "ASIO: foo_dsd_asio" from the dropdown menu.
3. Click the small triangle next to "Playback" and then on "ASIO".
4. In the "ASIO drivers" list, double-click "foo_dsd_asio".
5. In the subsequent window, select "Project Box Asio Driver" in the "ASIO Driver" dropdown menu.
6. In the same window, select "DoP Marker 0x05/0xFA" in the "DSD Playback Method" dropdown menu.
7. Close the window.
Configuring SACD Settings:
1. In the Preferences window, navigate to Tools → SACD.
2. In the "ASIO Driver mode" dropdown menu, select "DSD".
3. Close the Preferences window by clicking "OK".
You can now playback DSD files (DSF and DFF extensions) by dragging and dropping them into Foobar2000 or using the File menu.
Disclaimer: Downloads from the internet are at your own risk. Pro-Ject Audio Systems is not responsible for software sourced from the internet or any resulting damage or problems. Always check downloads with up-to-date antivirus software.
Replacing Batteries
Proceed as follows:
- Unlock and slide open the battery case cover.
- Replace the battery, ensuring correct polarity.
- Close the battery case cover.
Battery Type: 1 x CR2032 / 3V or 1 x CR2025 / 3V.
Disposal: Do not dispose of batteries as ordinary domestic waste. Please use appropriate collection sites, typically found at supermarkets and drugstores.
Technical Specifications
Product: Pro-Ject Pre Box DS2 Digital
- Analogue Inputs: 1x Line In (RCA), 1x Phono Line In (RCA)
- Phono Input Specifications: MM: 47kohms/50pF; MC: 10ohms
- Digital Inputs: 1x coax (S/PDIF), 2x optical (TOSlink®), USB B, Bluetooth(aptX)
- D/A-converter: AK4490 32-bit PCM 768kHz / DSD256
- Sampling Rate Converter: AK4137EQ upsampling to 768kHz
- Sampling Rates: 32/44.1/48/88.2/96/176.2/192/352.8/384/768 kHz
- DSD Support: DSD64, DSD128 and DSD256
- Filter Settings: 5 different selectable on front
- Frequency Response: 20Hz - 20kHz (+0/-1dB)
- Analogue Outputs: 6.3mm Headphone (front), 1x Subwoofer (RCA), 1x Fixed (RCA), 1x Variable Out (RCA)
- Output Voltage: 2.2 Veff (switchable +6dB gain gives 4.4 Veff)
- Minimal Recommended Headphone Impedance: 8ohms
- Headphone Output Power: 100mW/8ohms
- THD: 0.00085%
- Crosstalk: -117dB (10kHz@0dB)
- Signal to Noise Ratio: 113dB (20 - 20.000 kHz)
- Power Consumption: <1 watt standby, 600mA max
- Outboard Power Supply: 18V/1000mA DC (included)
- Dimensions W x H x D (D with sockets): 206 x 71 x 200 (220) aluminium / 240 x 72 x 199 (220) wood
- Weight (without power supply): 1.570g aluminium, 2.000g wood
Service
Should you encounter a problem that cannot be alleviated or identified, please contact your dealer for further advice. Only if the problem cannot be resolved there, the unit should be sent to the responsible distributor in your country.
Warranty
The manufacturer accepts no responsibility for damage caused by not adhering to these instructions for use. Modification or changes to any part of the product by unauthorized persons release the manufacturer from any liability over and above the lawful rights of the customer.
Copyright and Trademarks
Pro-Ject Audio Systems is a registered Trademark of H. Lichtenegger.
This guide was produced by: Pro-Ject Audio Systems. Copyright © 2017. All rights reserved.
The information was correct at the time of going to press. The manufacturer reserves the right to make changes to the technical specification without prior notice as deemed necessary to uphold the ongoing process of technical development.
Windows®, Windows XP®, Windows Vista®, Windows 7®, Windows 8®, Windows 10® are trademarks of the Microsoft group of companies. Mac® and Mac OS® are trademarks of Apple Inc., registered in the U.S. and other countries. TOSlink® is a registered trademark of Toshiba corporation. Dolby® is a registered trademark of Dolby Laboratories. DTS™ is a registered trademark of DTS, Inc. DSD and the DSD logo are trademarks of Sony Corporation.
