The X8 is just a bit too large and conspicuous for me so I got the X6 because it's more useful in more random situations and easier to carry around. I'm an engineer so I took it apart and examined all the circuitry and general build. My conclusion is that TEAC/Tascam did a pretty fantastic job with the design for this unit. Much of the money you're paying, is going into the circuitry - which is indeed complex and high quality. Very good opamps (OPA1678's, which you can replace with OPA1656's if you like, for a little improvement), great ADCs (AKM AK5704's), high quality dual clocks from Kyushu Dentsu (KDK) - one for 44.1kHz, and another for 48/96kHz. The device runs on a single core Cortex-M7 ARM CPU at 600MHz, and it has 128MB of RAM. All the audio routing and processing is done on an CPLD/FPGA from Lattice which costs twice as much as the CPU. I'm guessing that the reverb functionality is implemented through it as well, effectively "in hardware".The good:-What I haven't see anyone mention - you can run the X6 (and presumably X8 as well) from a USB-C power bank, even without the AA present in the unit. I got an estimate of 60-90 runtime hours from a 25000mAh battery bank. It seems to have good power filtering for USB-C as well, so power noise doesn't couple into the analog circuits much at all.-Excellent circuit design (unit is engineered by TEAC with their extensive experience in audio, they have their high-end "Esoteric" parent brand after all).-Internal shielding is fairly elaborate (thick metal plate between digital and analog portions of the circuit, which keeps self-noise very low. BUT, this device is not as resistant to external interference (plastic case and all). If you place a phone or other electronics next to this device, it will pick up various EMI interference which will be extremely audible especially at high gain. So the upside is that the device is light (unlike heavy chonkers from Sound Devices etc), but you don't have as much external electrical noise immunity. Keep this in mind~-Sealed dome switches for keys (not membranes) - should last for a long time.-Plastic case is actually pretty high-precision and cleverly designed when it comes to molding. Subtle thing and no one likes plastic anyways, but it's well made at least.-Pleasant noise floor signature (gained up to the max, the noise sounds like brown more than white - it's soft)-Built-in mics are very sensitive with low self-noise for the price of the device-Gimmicks aside ("ASMR" mode etc lol), the device is straightforward to use. UI isn't the best nor the most intuitive but you get used to it quickly. Just accept it and move on lol.-32-bit mode is indeed excellent and captures the entire dynamic range of sounds with its dual ADCs per input, so you can recover peaks in post, or gain up the audio with no drawbacks-I tested this device with a Samsung S24 Ultra and it works fine as an audio interface there. I was able to get MotionCam Pro to use this device as a sound input (only when the X6 is set to 48kHz/32-bit), at which point MotionCam Pro was able to include 32-bit 48kHz uncompressed audio from the X6 into the RAW video files, which is what I wanted. You do have to set the audio profile to "Unprocessed" in MotionCam. I've written my own multi-threaded decoder for their .mcraw files for Linux (.mcraw to DNG+Proxy), so I can now have RAW video + "RAW" (32-bit) audio in single files that are easy to edit, which is pretttyyy coooool as probably a world first.The bad:-The #1 issue to me as an engineer (which I haven't seen anyone bring up before for this device), is in how the device handles its high pass filter (low-cut filter) when it comes to the BUILT-IN mics. This filter is applied digitally (post-preamp, post-ADC), which means that when it comes to wind or loud surrounding bass, the built-in mics will already clip the preamp/ADCs, so you're applying low-cut to a clipped waveform at that point, which will retain all the distortion components from that clipping. This is terrible, and I've seen complaints on Reddit about this device clipping lows in unexpected situations. Many external mics have low-cut filters built into the mics - which is what you want. Low-cut filters should ideally happen in the analog domain, before digitizing. This would've required more parts and board space, so I can see why TEAC/Tascam didn't do that. But - that's how you'd avoid clipping your preamps/ADCs. This device saves money by doing this digitally, but that means that to use this recorder professionally in the field, you have to have phenomenal quality wind filters on it. Cheap stuff won't do, cause you REALLY need to get rid of anything that's gonna clip the lows on those mics (which are unfortunately/fortunately great at capturing low frequencies).-Given that all the money went into the circuitry, you sacrifice overall build quality. Almost everything is plastic. Case contact is highly audible with built-in mics, so you need an isolated shock mount etc if you're going to be moving around.-Built-in mics are non-removable on the X6 and removable on the X8, with 10mm capsules on the X6 and 14mm on the X8. The mics themselves are excellent. The way they're installed into the case is kind of cheap, and if you ever drop this unit onto the mics (or have a hard bump into a wall or something), they will definitely smash into pieces - so you have to be careful. On the X6, the mic wires are directly soldered to the PCB with no connectors. In one sense, it might make them more robust than the X8's connectors which might eventually get some corrosion/wear, but replacing mics on the X6 would be troublesome. Still completely possible though, if TEAC sells you replacements.Overall:Best audio quality out of the box for the price, loaded with functionality. BT functionality with dongle for remote recording/adjusting, ability to use the unit as an audio interface in Windows/Android/macOS/Linux, true 32-bit recording, decent battery life, ability to power via USB-C (with a 5V/1.5A capable supply, though the unit only used 5V/200-300mA in practice). Convoluted UI (you'll get used to it) and cheap construction are the only drawbacks.

Pros-Buena calidad de sonido-Menus aceptables, aunque podría ser mejor-Audio a 32 bits si hace la diferencia pára no perder información.-Se puede alimentar con una powerbank por el puerto usb-c-Varios modos de grabación-El modo Manual de grabación esta bien diseñadoContras-Muy baja velocidad de transferencia via el puerto Usb-C, (mejor extraer la micro sd para respaldar)-Consume más bateria de los esperado. Con las 4 baterías AA dura unas 10 hr aprox.-En funcionamiento la pantalla no se puede apagar completamente, solo se reduce el brillo. Y esto impacta en la batería.Ya deberían incluir el case en este tipo de artículos.

On advice from a friend, I sent this back and purchased an older model from a different brand. This was a mistake. The ease of use that this device offers beats the competition, hands down. I had to do a lot less work in post with the files recorded by the X6. Is it light? Yes. Are the mics plastic? Yes, but the ease of use and sound quality are what I want in a device. I will order this one again soon.

Great product!!

I really like the quality of the mics, and the 32-bit float recording. There are over a thousand uses for this unit. I highly recommend it.

It seems they released this product with the color touchscreen menu barely working. In early firmware, the basic "apps" were in color touchscreen, but everything else the black/white menu. And it was (and remains) unpleasantly cumbersome to switch between them, which you must do to get anything done.To give you an idea how bad it is, when you go into one of the apps, "microphone", "manual", "podcast", "SD card reader", etc., you can't go backwards to the main menu by touching a button! You have to press the physical "menu" key to get back to the 2-tone menu and then go into settings or back into "launcher" (color) to pick another app. I called tech support and asked them to put in that complaint. It's so embarrassing, that lack of home menu/back button on each app screen, I didn't even push the support guy on the WTF TASCAM!If you want to know how starved for R&D money the existing audio industry is, buy this device.That said, the device has tons of potential. I'm not going to go into all the ideas about how they can bring new life to these devices, but has to do with audio data modeling. Recording audio is a commodity. 32-bit float is not a real improvement (indeed, they're almost fraudulent in saying it will help any user of this product). What users want today is tons of charts and reports about what is being recorded. Ideas on how to maximum your gain settings or mic placement. Room acoustics. Again, recording devices with an LCD screen are 20 years old.Will TASCAM be able to do this, or will they go out of business and some young people in a garage come out with something to make me excited. I mean, again, c'mon, no go back to home on the touch screen?I'll come back and write updates as they continue to improve the device through firmware. It is happening. So I'm hoping to come back in the months ahead with good news to report. But TASCAM, if you're reading this, time to pull some all-nighters and finish the color and touch screen menu system.