Why is Mixer A More Expensive than Mixer B?


The Azden FMX-42a and the FMX-42 portable field mixers are nearly identical in appearance, yet the price tag on the FMX-42a is over $100 more than the FMX-42. In this post I'll clearly explain why this is so, and how the additional features on the FMX-42a can greatly benefit you when mixing audio in the field.

The key difference between these two portable field mixers is that the FMX-42a features a 10-pin connector and a mini-plug return input. These inputs allow you to connect the headphone output of a video camera to the mixer. This enables the operator of the mixer to listen to what the audio sounds like inside of the camera, remotely from the mixer. This way, the sound person can hear exactly what's being recorded on the camera. 

In the event that the audio connection to the camera is broken, the operator will immediately be able to hear this and correct the error. If levels are too loud or soft in the camera, the sound person can make adjustments to compensate for this.

When you're connecting a field mixer to a video camera, it's a good idea to use a "breakaway cable" to connect the two. A breakaway cable will connect the XLR outputs of the mixer to the XLR inputs of the camera, as well as the headphone output of the camera to the mini-plug return on the FMX-42a. They're called breakaway cables because there's a mechanism that allows you to quickly attach and detach the cable, without having to plug and unplug all of the connections on the camera. It's a really useful way to save time on set.

Another advantage that the FMX-42a has over the FMX-42 is that you can turn off the lights on the VU meters in order to conserve battery power. It's a bit of a minor detail, but every ounce of battery life that you can save in the field will make a difference.

Both of these mixers feature a mini-plug output in addition to the main XLR outputs. This enables you to send the audio from the FMX-42a and the FMX-42 to two places as opposed to one. You can record your audio directly into two separate video cameras, or into a single camera and a field recorder. Plus, if you're working with a video camera or a recording device that doesn't have XLR inputs, the mini-plug connection will save the day.

It's always a good idea to make more than one copy of the audio that you're recording in a shoot. That's why it's a good idea to send the audio to more than one camera if you're working on a multi-camera shoot, or to make a back-up copy on a portable digital recorder in addition to recording into a video camera.

With switchable phantom power on every input, the ability to accept line or mic level signals and an optional limiter on every channel, both of these models are really well-rounded field mixers. If you want the extra ability to monitor the return audio from the connected video camera, then the the FMX-42a is worth the extra money.

If you have any questions about location mixing for video and film shoots, we encourage you to post them in the Comments section!

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Very useful article, thanks. Only I'm a little confused about what the added 10-pin jack is for. You talk about the mini jack allowing audio return from the camera, but how does the 10-pin connection factor in? Seems like a pretty fancy port just for monitoring audio. (Do 10-pin audio cables even exist?) 

I'm also not quite clear about the "breakaway cable" concept. Is this something that the 42a comes with that the 42 doesn't? And what kind of connector/mechanism is used besides the XLR and minis?

Thanks. Hope I'm not being too dense!

Hi Anonymous!

Thanks for posting your question. You're definitely not being too dense. This stuff gets really confusing.

On the FMX-42a, the mini-plug return input and the 10-pin connector both do exactly the same thing. They're both designed to accept the headphone output of the camera. The mini-plug return input is the more practical way of doing this, because the headphone output on the camera is also going to be mini-plug. The FMX-42a just gives you two ways of doing this. B&H doesn't sell a cable that's a 10-pin connector to a mini-plug male, which is what you would need to use that connector. This is the kind of cable that you would likely have to order from a dedicated location audio shop the builds custom cables.

For a better understanding of the breakaway cable concept, imagine you're on a set. There's a sound person, a DP, and a couple of grips setting up the lights. The DP and the grips are busy messing around with the lights, trying to get the shot to look its best. The sound person is staying out of their way for the most part, letting them concentrate. When the DP and grips are about ready to go, the sound person approaches them with a breakaway cable and asks if they can attach it to the camera. The DP allows them to do it.

The sound person then attaches the breakaway cable to the camera's 2 XLR inputs, and to the camera's headphone output (so they can monitor the return audio from the camera through their field mixer). The crew shoots the scene, and everything goes well. Immediately after finishing that shot, they have to move all of the equipment (camera, tripod, lights, etc.) to the other side of the room to shoot another scene. With the breakaway cable in place, the audio person doesn't have to unplug all of the connections to the camera. There's a small mechanism on the camera's end of the breakaway cable that allows you to detach the cable without having to unplug anything from the camera. Someone on the crew simply detaches this mechanism, and the camera and audio person are no longer tethered together.

When the DP and grips have finished setting up the shot on the other side of the room, the sound person can quickly re-connect to the breakaway cable without having to plug all of the connectors into the camera. It may seem like a minor detail, but on a busy set where time is precious, it helps speed things. It also helps the DP's state of mind if the audio person doesn't have to touch the camera more than necessary.

You can use a breakaway cable with either the FMX-42a or the FMX-42. However, the FMX-42 has no return input, so you could only use a breakaway cable to connect the XLR's.

Thanks, that definitely clears things up. Articles such as this (comparing Product A to Product B) can be very useful, and I hope B&H will do more of them in the future.

Is this the proper breakaway cable to use with the 10 pin Hirose connector on the Azden FMX-42a if you wanted to connect to the camera with just the Hirose connectors?  


That would allow the XLR output to go to a second camera if necessary correct?