I’ve been covering microphones and their accessories a fair bit lately, so I thought it’d be fun to take one apart and see what’s inside. Not just any old mic with an XLR, TRS or other analog output, mind you; I also wanted my dissection to circuitry-comprehend the ADC (analog to digital) stage, too. Though, at the mainstream (translation: low price) point I was focusing on, I fully expected that not all of the electronics bits:
- Phantom power
would end up wrapped up in a single chip.
I found my victim in the form of JLab’s Talk GO, which earlier this summer set me back only $15.29 plus tax (and with free shipping to boot) from Amazon company Woot!, in contrast to the $49 (new) and $25 (refurbished) prices quoted on the manufacturer’s website.
Note that the only part of the product that actually lights up in use is the base; the tripod tips and capsules’ cover are iridescent blue in color but only bright in adequate ambient light.
Relevant specs include:
- 24-bit, 96 kHz digital output
- Integrated volume control and mute switch
- Dual condenser capsules (in contrast to the JLab-claimed single-capsule approach taken by the well-known mainstream market creator, Blue-now-Logitech’s Snowball), one 14 mm in size and the other 9 mm
- 20 Hz – 20 kHz frequency response (albeit absent a detailed graph to show linear-or-not response at various points across the range)
- 118 dB max input sound pressure level (SPL) before distorting
- And two pickup pattern options: cardioid and omnidirectional
Higher-end variants of the JLab Talk family support additional pickup patterns—stereo and bidirectional—and/or a higher 192 kHz output sampling rate. Keep in mind that sample size and sampling rate, whether 96 or 192 kHz, are irrelevant if the captured audio quality isn’t sufficient. That said, the Talk GO is well reviewed, especially considering its price point (and assuming, of course, that you’re into iridescent blue).
Here are a few more “stock” shots to whet your appetite:
Along with a promo video:
And now, ladies and gentlemen, here we go!
Slip off the outer cardboard sleeve…
Flip open the lid, and (most of) the contents come into view:
Here’s the microphone and (folded-up) stand, as-usual accompanied by a 0.75″ (19.1 mm) diameter U.S. penny for size comparison purposes (the microphone has dimensions of 127 x 55 x 55mm, 150 x 195 x 195mm with the stand installed, and weighs 130 grams, 299.3 grams including stand. The USB cable weighs 46.5 grams standalone):
A few shots of the unfolded stand standalone, including a closeup of one leg with product info stamped on it:
Underneath it in the box was the 5/8″ screw-based input for swivel mounting purposes:
Now for the “extras”; system connection cable and typical (at this price point) scant literature:
Now for our victim. First the front:
Back, revealing the mounting hole for the aforementioned 5/8” screw:
Left and right (respective) sides:
This last shot begs for some commentary before continuing. The only allusions I can find to the 3.5 mm audio output on the product page, aside from its presence in the “stock” photos, are the mention of “volume” (which I initially thought was dumbed-down terminology for microphone “gain”, obviously prior to the ADC stage…which, I’m now assuming, is alternatively handled in-connected-computer) and to “latency = 0” (which is obviously not achievable over USB, but is apparently supported over headphones, speakers or other local-connection audio peripheral). Also, the documentation refers to USB-C as being an “input”, which is true only with respect to power delivery…it’s an “output” for audio purposes.
And speaking of power, there’s this interesting tidbit:
Talk GO will not work through a power bank/battery pack. It will only work with USB-A input with an operating system.
That’s, I think, a convoluted way of saying that you need to use the included (or another) USB-C to USB-A cable, connected to a computer’s USB-A port. Gee, where else have I recently come across a USB-C-inclusive peripheral that won’t work with a USB-C host? And it’s a particularly problematic constraint considering the increasing commonality of USB-A-less computers.
Rant over; onward. My first attempt at disassembly involved twisting the top off the mic, which was effective but also resulted in the disconnection of a red wire still soldered at the other end to the mesh surrounding the capsules. The wire’s intent is to “ground” the mesh to prevent audible “hum” when a user (mouth, specifically) gets close to it. What it originally connected to on the other end (mic body? PCB?) remains unknown to me, although I have a theory (keep reading).
Let’s complete the dissection of the twisted-off portion before continuing:
Now back to the “guts” of the teardown project. The larger (14 mm) condenser capsule is in front, implementing the cardioid pickup pattern, with the smaller (9 mm) capsule behind it used for audio-pickup augmentation in supporting the alternative omnidirectional pattern.
Here are multi-perspective closeups of both capsules:
I’m sure you’ve already noticed that they’re surrounded by rubberized housings that, among other things, suppress environmental vibration transfer to the capsules’ membranes. That flexibility extends all the way to their mounts to the base, of course:
Next question: how to get inside? My initial efforts to “jimmy” the threshold between base and body were unsuccessful, save for confirming that the latter was metal vs plastic:
So, I turned my attention to the underside, which proved to be more fruitful:
Remove three screws:
And the underside assembly pops right out:
A bit of foreshadowing: the white female plug, matched up with the red male jack, routes to the larger front capsule. And…you guessed it…the wiring associated with the blue female plug, matched up with the white male jack, ends up at the smaller rear capsule.
Look closely and you’ll see that the former is labeled as “required” (REQ) while latter is “2”. My guess is that this PCB was intended to do double-duty with an even simpler single condenser capsule and cardioid-only pickup pattern mic.
Here’s the other side of the assembly, minus the sticker that initially covered it:
Some side views:
And now let’s get the two halves of the assembly “sandwich” apart. Easily disconnected plastic “clips” comprised the bulk of the task, along with popping off the “volume” control axis:
The now-exposed other side of the base is unmemorable:
The now-exposed other side of PCB less so, but still fairly bland (unless, I guess, you’re into passives, potentiometer, connectors, a mute switch and a ring of multicolor LEDs):
Even though we’ve already seen it once as part of the assemblage, let’s look at that top side of the PCB again now that it’s free and clear:
Turns out JLab was able to integrate (pretty much, again save for some passives and other bits and pieces) everything into one IC. It’s Cmedia’s CM6533, an SoC containing essentially everything needed to implement the microphone design:
- 8051 microcontroller core (acting as the system processor)
- USB 2.0 interface (interesting; that may explain why even though the connection to the outside world is USB-C, it needs to mate with USB-A on the other end of the cable)
- Tri-color PWM LED driver
- Two-channel audio ADC and DAC
- Five-band audio equalizer function
- 256 KBytes of flash memory
- 4 KBytes of ROM, and
- 32 KBytes of SRAM
Plus, an optional S/PDIF output, not leveraged in this particular implementation.
Three more (side view) shots of the PCB before we proceed:
Onward again. With the assembly out of the way:
The internal chassis slides right out the bottom (recall that I initially tried to pull it out the top):
See that tape on one side?
Going back to that ground wire for the mesh that I showed you earlier, I wonder if it (with a now-broken-off insulation-exposed end) was taped to the metal (albeit painted) side of the microphone. Thoughts, readers?
In that earlier picture I showed with the inner chassis still in place, you might have noticed three more screws up toward the top of the microphone. I was only able to get two of them out; the head on the third one stripped in the process of my unscrew attempt:
Nevertheless, in spite of my subsequent inability to separate the two halves of the inner chassis, I was still able to pull the cabling and connectors for the mic capsules out the hole in the top:
In closing, a few shots of the larger front condenser capsule separated from its rubber housing:
Same goes for the smaller rear capsule:
And with that, I’m going to “drop the mic”, go on mute and wrap up this writeup. Comments are as-always appreciated!
—Brian Dipert is the E-in-Chief of the Edge AI and Vision Alliance, and a Senior Analyst at BDTI and Editor-in-Chief of InsideDSP, the company’s online newsletter.