DM100 Dolby Bitstream Analyzer

Print-friendly version 

The Dolby DM100 is a portable, handheld diagnostic tool that can monitor and generate Dolby Digital, Dolby E, and PCM bitstreams.

The DM100 Dolby^® Bitstream Analyzer is a uniquely efficient tool for end-to-end system testing. With its built-in test-signal generator, the DM100 allows audio system integrators and service engineers to quickly monitor and check the integrity and composition of Dolby Digital, Dolby E, and PCM signals routed through production, broadcast, cable, and satellite facilities, or even a home theater system.

The DM100 accepts digital input signals via XLR, BNC, and Toslink™ optical connectors. The unit identifies the format of the input signal—Dolby Digital, Dolby E, or PCM—and activates the appropriate built-in decoder. A standard 1/8-inch stereo headphone jack can be switched to monitor any two decoded channels or a downmix of the whole program, while a small built-in speaker provides a mono output.

A preselected set of useful Dolby Digital and Dolby E test bitstreams is stored in internal nonvolatile RAM, and users can change the set in the field via software download from the included CD-ROM. The DM100 can generate the selected bitstream simultaneously on all the output connectors, even while receiving and decoding an input signal. The DM100 is also capable of generating two-channel PCM signals. In this mode, the user can select the output waveform type (white noise, pink noise, sine, square), amplitude, and frequency. A serial port allows software upgrades and error and status logging via a Windows^®-based PC.

A pass-through mode permits modification of the input signal’s AES channel status bits before passing the signal to the output connectors. The input signal can still be monitored at the same time. Monitoring capabilities include error detection at the AES3 layer and within the coded audio layers (that is, for Dolby Digital and Dolby E bitstreams), including SMPTE 337 formatting information.

The DM100 is powered by four AA batteries or by an included wall-mounted DC power supply, and it ships with a soft carrying case.