18 Jun 2015

dBbox2 – Audio Tests Made Simple

The dBbox2 allows monitoring, metering and generation of analogue, AES/EBU & SPDIF audio from a pocket sized box with cable tester and 4 wire interface. The unit features a simple five key menu interface to make any test as simple as possible.

It allows you to monitor mono or stereo line level analogue inputs with the use of an in-built speaker ¼ inch or 3.5mm headphone jacks. Undertake meter readings using either PPM or VU scales, which can also be achieved with the stereo phase meter.

Monitor AES/EBU balanced or unbalanced inputs using the built in speaker or headphones. Meter using -18dBFS, -20dBFS, PPM or VU scale with stereo phase meter. The unit also allows you to monitor microphone level analogue inputs, with or without 48v phantom power, using the built in speaker or headphones. Run meter tests using either PPM or VU meter scale with stereo phase meter.


The AES analysis sample rate feature enables the user to check status and data errors.

The built-in microphone can also be used to talk to analogue outputs and can also be used to talk to AES outputs with a choice of levels and with a built in limiter. Tone generator frequency is adjustable in third octave steps, with level from +10 to -60dBu in 1dB steps. Generate steady tone, tone sweep, GLITS, EBU, left only, right only, on both analogue and AES/EBU outputs.

The Audio tester allows the user to generate pink noise and send to left/right/both outputs in both analogue and AES/EBU with a choice of levels in 1dB steps from +10dBu to -60dBu.
The unit can send its external mic to analogue and AES outputs with gain adjust and phantom power.


The MIDI receiver has an identifying channel, note on/off and note number. The MIDI transmitter has a selection of note, channel and velocity, note on and note off and MIDI signals can also be analysed with pass through.

The dBbox2 can be used as an analogue to digital or a digital to analogue converter with adjustable gain in 1dB steps, a limiter and HF, LF and Mid-range equalisation.
The unit also includes a mono or stereo microphone amplifier with 48v phantom power and analogue, AES/EBU or SPDIF output. This includes adjustable gain in 1dB steps, a limiter and HF, LF and Mid-range equalisation.

Output tone and incoming audio can be monitored simultaneously using Analogue or AES inputs and outputs, which is useful for frequency response and performance tests.
Extend battery life with intelligent power control. The dBbox2’s intelligent power control automatically switches off all electronics not required for the current task extending battery life. A dynamic battery level indicator shows if you have enough battery power for a selected function.

Other notable features include:

• Four wire interface using the built in microphone and speaker or headphones.
• Monitor and meter 2 wire channels.
• Test XLR, BNC and MIDI cables.
• Switchable backlight.
• Update firmware online using the dBbox2 USB port via CTP Systems web site.
• External power input via a standard mini USB.
• Protective case available with belt mount.
• A soft case for the unit and a universal mains adaptor.
• Dimensions: 146mm tall, 89mm wide, 48mm deep.
• 9V PP3 size alkaline battery has a battery life is around 8 hours continuous with optimal power setting selected.
• The SPDIF functions are available on the input and output BNC connectors. If required compact adaptors can be supplied to convert to phono’s.

The architecture of the dBbox2 is based around a powerful digital signal processor and a separate microcontroller allowing the ability for many more features to be added in the future with just a firmware download from the supplier’s website. CTP Systems are working on software to allow the dBbox2 to be used as a ‘test hub’ allowing it to be controlled by both PC and Mac software with test sequences and results available on the computer screen.


Published monthly since 1991, our famous AV industry magazine is free for download or pay for print. Subscribers also receive CX News, our free weekly email with the latest industry news and jobs.