This is a quick review, and associated video, of a dual-transmitter wireless microphone kit by Comica, the WM300A. Besides its affordability, what this kit brings to the table is the ability to feed two transmitter packs, into one receiver. My point of comparison is the RodeLink system I’ve been using for about a year, which has worked out well for me because it offers the option of hooking straight into a shotgun microphone with phantom power. But it’s worth mentioning that you can get a similar module from Comica for this system, too, that can simultaneously transmit with one of the lavalier packs. You’ll notice looking at the Rode kit that there are no external antennas, partly because of its high 2.4 GHz frequency band, which limits its range a little, and it’s vulnerable to interference from Wi-Fi devices that share the same unlicensed spectrum, while preferring walls to bounce off. In this post, we’ll explore all the features of the Comica system, which includes that second transmitter sending at the same time, which isn’t possible using the RodeLink.
Starting with the receiver seen at right, besides twin antennas, you’ll also notice an IR or infrared port that’s one way to synchronize the transmitters with the receiver. The 3.5mm output jack is stereo, which is especially important here because you can make it allocate one transmitter to the left channel, and the other to the right.
The transmitter also has a micro-USB port, for charging its internal lithium battery. Unfortunately there’s no backup alternative to get power from alkaline batteries, but you can always try tethering a USB power bank.
In the picture below, you can see both of the transmitters, with one included lavalier microphone plugged in and secured with a screw-in connector. The other included transmitter is identical, with its own lav mic, and just like the receiver, they both have internal batteries charged through a micro-USB port on the bottom.
I like how there’s not only the usual belt clip on the back of each transmitter, but also a 1/4″-20 mounting screw socket, which is something you normally only see on the receiver side. The listed frequency range of 520-580 MHz tells you that this system uses older UHF frequencies, which have pros and cons compared to the RodeLink’s 2.4 GHz spectrum. The signal travels farther, but the frequency hopping to avoid interference, is less sophisticated.
We see this in the transmitter menus, with the first option to select between Group A at the lower end of 500 MHz, and Group B at the upper end. But also, there are channels within those ranges, and you can either manually select them, or automatically sync them using that IR port. Really the goal is to avoid interference if you literally hear it, whereas that sophisticated RodeLink system listens thousands of times per second and hops around to avoid interference before you hear it. So basically, this is another a case of pros and cons.
In the transmitter menus, you can specify the impedance at the audio input, between microphone and line level. You can also decide whether to add a low cut filter that can reduce hum or wind noise, at low intensity or high intensity. And you can also boost each radio’s power output to a high setting if necessary, using more battery. Finally, there’s a muting option in the menu, but it’s easiest to just press the power button with one tap, and you’ll see the top Audio light turn red.
One really important menu option on the receiver is to select between Stereo output and Mono output. If you’re only using one transmitter, then Mono is just fine, and you’ll get the same audio in the left and right channels at the physical stereo mini-plug output. But if you’re using two transmitters at once, then it’s wisest to choose Stereo so that one transmitter is on the left side, and the other on the right — this way, you can control the levels separately later on. But you’ll need to be really careful in post-production, to reallocate those channels onto separate tracks so they aren’t sounding hard-left and hard-right in the final export.
Another nice feature is the ability to power off a transmitter remotely from the receiver. And you can also set the volume at this pre-amp phase, especially to avoid clipping in really loud environments. There’s a bluish backlight on the LCD display, but to save energy, it automatically turns off after a time you can set. And of course, there are the usual language settings, and menu-based ability to do a factory reset, besides a reset pinhole at the bottom of the unit.
In the associated video with this post, you can hear a series of sound quality tests using live audio from both the Comica and RodeLink systems, for comparison, fed into a Zoom F6 32-bit float audio recorder.
To wrap things up, I do hear a small quality difference that’s better on the RodeLink probably because of its Rode lavalier microphone, so it’s worth getting better lavs and trying that out on the Comica transmitters. But the versatility of being able to get two separate transmitters feeding into one receiver, is the best feature of this Comica kit. Other folks like Sony are just starting to launch products with the feature, but at a much higher price point. The all-metal chassis on each of these Comica units feel durable, and performance seems adequate, so you might want to save a few bucks and give these a try.