Hello, this is Jooyoung Kim, an audio engineer and music producer.
Recently, I’ve been busy conducting research related to Korean traditional musical instruments, which requires several listening tests. Therefore, I met Yeonjoon Yoon, a composer and pianist who has worked with some Korean traditional musicians.
After the test, I asked him when the album that we worked on together last year would be released. He surprisingly said it had already been released!
So I decided to introduce the album.
I used Peluso P-87 microphones for stereo miking on the grand piano, and Rode NT-55 microphones for the drum overheads and ambience positions. I also positioned two Shure SM57s on the top and bottom of the snare. I can’t quite remember, but I believe there was a rack for the kick microphone, so I likely used a Shure SM57 for that role as well.
There is also a peculiar musical instrument called the Saenghwang (a mouth organ). I remember that I installed a Peluso CEMC 6 over the head of the musician.
I used a Midas m32 console for both live mixing and recording simultaneously.
Yes, that’s all—maybe. It’s been about 9 months, so I can’t remember all the details accurately.
I only remember that the venue’s interior was made of concrete and brick, so it had a pretty long reverb time. Because of that, I struggled with the acoustics while mixing the live sound. However, in the recorded tracks, the piano actually sounded a bit too dry, so the artist wanted to add a huge amount of ambience—around -10 dB (whereas in popular music, ambience effects like reverbs are usually added around -30 to -20 dB).
These are unique and interesting tracks, so check them out..!
As you know if you read my DIY hardware post series, about a month ago, I finished wiring and assembling all the components for my DIY audio hardware. When I powered it on, I immediately ran into two major problems. Only the left channel’s meter responded while the right channel’s meter remained completely dead, and there was no audio output at all.
I wasn’t even sure where to begin troubleshooting. After wiring up all the components for my DIY audio hardware, I ran into two major problems right away. First, only the left channel’s meter responded, while the right channel’s meter remained completely dead. Second, there was no audio output at all.
After spending so much time on the project without making any progress, I became so frustrated that I stopped working on it for a while. It honestly felt like burnout.
When I came back to it yesterday, I started thinking more logically. The meter was connected just before the THAT1646 output driver stage. If the left meter was responding correctly, that meant the entire signal path leading up to that point had to be functioning. In other words, the problem couldn’t be somewhere earlier in the circuit.
Following that line of reasoning, I first discovered that I had simply wired the right meter incorrectly. That explained why only the left meter had been moving.
With the meter issue solved, the only remaining suspect for the missing audio output was the THAT1646 itself. So I started digging into its documentation and pinout.
However, after replacing the devices, I discovered another problem. A significant amount of broadband noise was present, measuring higher than -75 dBFS across nearly the entire frequency spectrum.
I went back through the schematics and the datasheets, comparing my design with the recommended application circuits. That’s when I realized I had made a fundamental mistake: I hadn’t included the power-supply bypass capacitors for either the OPA1612 op-amps or the THAT1646 output drivers.
Looking back, it seems obvious. High-performance analog ICs like these rely on proper local decoupling to keep their supply rails stable and free from high-frequency noise. Without those capacitors placed close to the power pins, the circuit is far more susceptible to noise and instability.
So, despite thinking I was finally done troubleshooting, I ended up ordering yet another batch of components. Now I’m waiting for the capacitors to arrive before I can continue.
At this point, the project is slowly turning into Frankenstein’s monster. Every problem I solve seems to require another small modification to the hardware. Hopefully, these will be the last stitches before it finally comes to life.
That’s it for today.
Lately, I’ve barely had enough time to breathe between studying English and working on my research, so progress on this project has been a little slower than I’d like.
On the bright side, I recently picked up an SPL Vitalizer MK3, so you can look forward to a review of that in an upcoming post.
Thanks for reading, and I’ll see you in the next one!
Jooyoung's Music Blog 