An original guide to checking what listeners and outside microphones hear. Includes room planning, fit observations, measurement limits, and practical worksheets without invented sound-reduction claims.
DM4 vs. DM246: Choosing a Four-Channel Courtroom Recording System
Choose the recording workflow that fits your team, then compare complete microphone packages and verify the saved files through transcription review.
DM4 versus DM246: where the recording happens
The central difference between the Martel DM4 and DM246 is where the recording work happens. The DM4 arrangement uses a compatible Windows computer with recording software and a USB audio interface. The DM246 arrangement records to removable media in a standalone recorder. Both can form part of a four-channel courtroom recording workflow, but they place different responsibilities on the operator, computer and supporting equipment.
This distinction matters more than the appearance of the carrying case. A buyer who already operates an approved recording computer may prefer a system that brings input controls and software together at that workstation. A buyer who needs to record without running a computer at the table may prefer a standalone recorder. Either buyer still needs microphone placement, monitoring, file management, backup arrangements and a way to review the resulting channels.
Four channels are useful because they can keep microphone feeds separate for later listening. They do not guarantee that each person appears on only one channel. Nearby microphones also hear the room, and seating arrangements can change. A channel may represent a witness position, a table or another recording zone rather than a permanently identified person. The operator must verify the channel map and the reviewer must understand it.
This guide compares the operating decisions behind the two systems. Product descriptions and package contents can change, so use the linked listings and a written quote to confirm the exact configuration you will receive. Examples here describe planning and acceptance exercises; they are not claims that Martel measured a particular room or certified a particular proceeding. The goal is to choose a system whose complete workflow you can explain, test and repeat.
Start with one sentence: “During recording, our primary audio file will be written by this device, to this destination, while this person checks it.” If your team cannot finish that sentence confidently, resolve the workflow before comparing accessories. It identifies the operational choice that separates these systems and gives every later purchase a clear purpose.
Compare the complete signal paths
| Decision | DM4 computer-based arrangement | DM246 standalone arrangement |
|---|---|---|
| Primary recording device | A compatible Windows computer running the recording software | The standalone recorder |
| Microphone entry point | The supplied multichannel USB interface in the selected package | The recorder's microphone inputs |
| Destination to verify | The software's selected recording folder and storage device | The recorder's selected supported media and recording settings |
| Computer during recording | Required for the DM4 recording workflow | Not required to operate the standalone recording path |
| Later review | Confirm the saved files and the intended multichannel playback workflow | Transfer the recorded files and confirm the intended multichannel playback workflow |
Read the table from left to right as a set of responsibilities, rather than as a scorecard. Removing the computer from live recording removes one group of dependencies from that stage. It does not eliminate all computer work: transferring, reviewing, transcribing and delivering files may still involve a computer. Conversely, using a computer for recording can put controls, file naming and other approved tasks together, but that convenience also makes the computer part of the recording system that must be prepared.
Draw the path for your actual quote. Include every microphone, cable, interface, recording destination and monitoring connection. Then draw the review path separately. A supplier may offer software alone, hardware with software, or a more complete microphone package under related names. A product family name is not an inventory of the box. Mark anything that your organization will supply, including the computer, storage, power arrangements and review workstation.
Finally, identify the boundaries between components. A live meter in recording software confirms activity at that point in the path. It does not by itself establish that the intended file was saved correctly. A headphone connection can monitor different points depending on the device and settings. Ask what that connection actually proves and include saved-file playback in acceptance. These distinctions are useful for either system and prevent a purchasing discussion from stopping at “we can hear the microphones.”
What the DM4 package asks of your computer

Martel's listed DM4 four-microphone package combines recording software, a four-channel USB interface, professional courtroom microphones, cables, stands, monitoring headphones and a carrying case. A compatible Windows computer is not included in that package. The computer is therefore an explicit purchasing and preparation item, even when an organization already owns a machine it hopes to use.
Confirm the supported Windows version and the current software requirements for the exact DM4 version supplied. Then compare those requirements with the actual computer, rather than with a general description such as “new laptop.” Check available connections, storage, power supply and the other approved applications that will run during the assignment. A computer that performs an office task satisfactorily has not yet demonstrated that the complete recording arrangement works.
Choose the recording destination deliberately. The operator should know which local folder receives the files, how much space remains and how to find a completed recording without searching recent documents. Organization-managed backup or synchronization can be valuable, but its behavior during active recording must be understood. Do not assume that a cloud icon means an open recording has already become a verified independent copy.
The USB connection is part of the signal path. Decide where the interface connects, whether an adapter or hub is necessary, and how cables will be protected from accidental movement. Test the arrangement you intend to deploy, including the computer's power connection and any required accessories. Replacing a direct connection with an untested hub on the morning of an assignment changes the system you previously accepted.
Computer preparation also includes operational ownership. Identify who can install authorized updates, resolve permissions, configure approved recording settings and recover the working arrangement after a repair. Keep a record of the tested configuration without exposing passwords or confidential material. If the designated operator cannot change a setting on a managed computer, arrange that support before the equipment arrives. DM4 is a sensible candidate when these computer responsibilities fit comfortably into the organization's normal work.
What standalone recording changes with the DM246

The DM246 moves live recording into a dedicated recorder. Martel describes it as a four-channel system with microphone inputs, phantom-power capability, recording to cards, and AC and battery operation. The exact package can differ by microphone selection and quantity. Confirm the quoted combination and the supported recording settings before treating a photograph as a complete list of supplied equipment.
A standalone recorder can simplify a portable assignment because the operator does not need a computer running the recording application at the table. It also gives the recorder's controls, display, media and power arrangements more importance. Practice identifying the active file, confirming that recording has started, checking each required channel and recognizing the remaining recording capacity. The useful question is whether the assigned operator can perform those checks consistently in the actual working position.
Removable media creates a clear transfer step. Decide who removes or connects the media, where the first copy goes, who checks the copy and when the media may be reused. Do not turn “the files are on the card” into an indefinite storage plan. The card is part of the recording workflow, and its custody and reuse need to fit your organization's requirements.
AC and battery options provide operating choices, but a buyer should verify how the delivered recorder behaves with the selected power configuration. Do not infer uninterrupted operation during every power event from the presence of both options. Ask for the relevant operating instructions and rehearse any permitted changeover procedure with disposable test audio. Record the configuration that was tested rather than assuming another battery type or power accessory will behave identically.
Physical controls deserve an ergonomic check too. Can the operator see the display without leaning across microphone cables? Can headphones be connected without stressing a socket? Is the recorder protected from papers, drinks and accidental button presses? A small dedicated device still needs a stable operating location. The DM246 is a strong candidate when independent live recording and a deliberate later transfer stage match the team's preferred routine.
Match the microphones before comparing recorder prices
Comparing a DM4 package with a DM246 package is meaningful only when the microphone arrangements serve the same task. Four supplied microphones, eight supplied microphones, directional pickup and omnidirectional pickup are different purchasing details. The number of microphones is also different from the number of separately recorded channels. Ask how each included microphone connects and where its signal appears in the saved result.
Start with a drawing of the occupied positions. Mark the operator, principal speaking locations, witness position, any standing presenter and any remote participant feed that must be captured through an approved connection. Note where papers, screens and table edges affect placement. A room plan tells Martel more than a label such as “small courtroom,” because two similarly sized rooms can have very different speaking arrangements.
A directional microphone can help emphasize sound from a chosen direction, but orientation and distance still matter. An omnidirectional microphone offers a different coverage pattern and still captures the surrounding acoustic environment. Neither description is a promise that distant speech will remain clear through room noise or overlapping conversation. Test the proposed microphone type in the positions it is intended to serve.
For each quoted package, ask for a microphone-to-channel map. If multiple microphones share an input through the supplied arrangement, identify which voices will be combined before recording. Once sources have been mixed together, later playback cannot restore the original separate electrical feeds. A four-channel recorder does not automatically create four isolated people, and adding microphones does not automatically create more recording tracks.
Compare cable lengths, stands, required power and packing arrangements as part of the same exercise. A package that contains suitable microphones but cannot reach the assigned positions is incomplete for that room. Allow for safe routing and strain relief without stretching a cable across a walkway. The better comparison is the cost and practicality of two complete, tested room arrangements, not the price of two boxes with different microphone contents.





