2024 Year in Review

Hello! I’m Jooyoung Kim, an engineer and music producer.

It’s already the last day of 2024…
It feels like I’ve barely done anything, yet the end of the year has come around again. 😊
This year, I want to take a moment to look back on what I’ve done.


First Half of the Year

In January, I started writing introductory posts about mixing techniques.
I’d been wanting to publish articles elsewhere, but after receiving rejections from various outlets, I decided to focus on writing consistently on my blog instead.

I lost count of how many times I revised those posts! Eventually, I submitted them to Kyobo Bookstore’s POD (Print on Demand) service. To my surprise, Joongpil Goo, an engineer from Klang Studio with extensive experience as an SM engineer, graciously wrote a recommendation for the book. Even now, it feels surreal! 😊

This was finally completed by late September, and it was quite an intense journey just to publish a single book.

From January to April, I worked with a studio called Studio Dolphin, producing YouTube videos where AI collaborated with indie musicians to create songs.
We used Soundraw for the AI-generated music, ChatGPT for lyrics, and melodies were composed by indie musicians. The challenge was to create a full song in just 90 minutes.

I participated as both an engineer and a panelist, but unfortunately, the videos didn’t garner much attention, and they’ve since been taken down.

At the start of January, I was extremely busy with various recording and mixing tasks for school projects. In February, I spent a lot of time preparing paperwork to apply for government-sponsored projects. Sadly, none of these applications were successful, which left me feeling rather deflated.

In March, I returned to school, and things got busier from there.

In May, I launched my English blog and started promoting Plugin Boutique products more actively, which kept me even busier.


Summer

From July to August, I worked on producing Danny Boy’s EP from start to finish.
I handled everything—recording, arranging, mixing, and mastering. 😊

At the same time, I collected measurement data for my thesis. The data turned out well enough that I’m now preparing to submit it to an international academic journal.

While processing the data, I found myself delving into coding—a field I never thought I’d explore! Surprisingly, tools like Copilot and ChatGPT were lifesavers. At first, I barely understood anything, but after asking countless questions, things started making sense. 😊


Second Half of the Year

September was tough. I applied for several positions but didn’t get any of them. My final interview was with the Gyeonggi Arts Center, but, well… things didn’t work out. Back in May, I’d also made it to the final round for a position at Kumho Art Hall at Yonsei University but was ultimately rejected. I guess that’s just how life goes. 😊

In October, I filmed a music video, and November passed without anything particularly noteworthy.

In December, I wrote a short paper about loudness in audio and submitted it to a domestic academic journal. It was accepted and will be published in early January.

Also, during this semester, a professor from Sorigeo joined the faculty, and I took his class. In collaboration with him, I gathered data for another research paper, spending two days on measurements. The data looks promising, but I haven’t organized it yet. Once I do, I plan to publish another paper and share the details. 😊

In addition to all this, I continued working on my own music, doing external mixing/mastering, composing/arranging, and providing guide vocals.


Unforgettable Projects

One of the most memorable projects this year was mastering the EP for the Bulkuksa Team’s Random Game. My favorite track was definitely “Microdust.”

A heads-up: the song contains explicit language. 😊

A friend had asked if I could master the track using only an MP3 demo, as they’d lost the original files. I was initially concerned about the sound quality but was blown away by how creative the music was. I couldn’t say no!

Some tracks were well-balanced, while others were completely off, but I managed to improve them significantly through proactive mastering. While the sound quality wasn’t ideal due to the limitations of MP3, the sheer fun of the music made up for it. 😊


Gear Purchases

  1. Stam Audio SA-4000 MK2 Compressor
  2. KEF Kube 15 MIE Subwoofer
  3. Stam Audio SA-2A Compressor
  4. Earthworks M30 Measurement Microphone
  5. Rack Cabinet and Patch Bay
  6. Wharfedale D310 Passive Speakers
  7. Cort A4 Bass
  8. A broken Heritage Audio Successor Compressor

I bought quite a bit this year…

Next year, I’m thinking of adding a tube microphone preamp and an EQ. Maybe another compressor or a mic too? The gear wishlist never ends! 😊

After Modifying My Stam Audio SA-2A

Hello! I’m Jooyoung Kim, mixing engineer & music producer.

Today, I’ll talk about what I did after the article, Record Before Modifying the Stam Audio SA-2A, and how sound changed.


First, let’s review the problems I encountered.

  1. Output gain is similar to input gain, when the GAIN knob is too low.
  2. Compression is started when PEAK REDUCTION knob is too high.
  3. It sounds so dull, like high frequency response is cut off

Otherwise, The Compress and Limit switch was positioned incorrectly. It was simply solved by wrench.


1) Potentiometer Changed..1

If you take off the cover of SA-2A’s knob, you could see a100k potentiometer at each parts. So, I thought that if I change a100k to a50k for gain knob, amount of change is more lower. Also, change a100k to a250k for peak reduction knob, compression would be change more earlier.

So I changed them first.

The green line is SA-2A hardware, the pink line is Waves’ CLA-2A.

It doesn’t seem bad at all! Otherwise, output gain is similar to input gain, when the GAIN knob is too low yet, I ordered A25K and A10K potentiometer too.


2) Vacuum Tubes Changed

I changed my 12AX7 tubes from jj electronics to mullard.

Frequency response and compression curve was not that different compared to jj electronics’. But it sounds much better than before. Harmonic distortion seems to have changed many aspects of the sound.


3) Changed Potentiometer Once Again..2

Upper image is a25k, The lower image shows the a10k potentiometer. You could see frequency response improved when the lower value of potentiometer is used! The problem isn’t solved but it sounds really good.

Red curve is UAD LA-2A Silver face, pink curve is WAVES CLA-2A, green curve is SA-2A.

Compared to UAD, it’s nice that it doesn’t add such an overwhelming saturation. And compared to Waves, I like that it doesn’t have that overly compressed feel.

I think it’s worth trying out more simple tools like this in the future. Next time, maybe an EQ or a Comp DIY kit…!

See you in next post! 🙂

I Released a New Song After a Long Time… The Tremor

Hello! I’m Jooyoung Kim, a mixing engineer and music producer.

I always introduce myself as a singer-songwriter, but honestly, I’ve been working as an engineer so much that I sometimes question whether calling myself a singer-songwriter is still accurate. 😅

That said, I finally released a new song after what feels like forever!

It took way longer than expected… haha. Doesn’t my outfit look a bit chilly? This was filmed in mid-October, and it was still slightly warm back then. But I got so busy in the meantime that everything kept getting delayed until it was freezing winter.


The song itself was actually written late last year. Yes… this too got pushed back, as you might have guessed.

I remember coming up with the idea after I left my job at Forest Record. I was feeling a bit deflated, like a balloon losing its air. Around that time, I applied to graduate school at Sangmyung University.

I spent an entire day playing a simple guitar chord progression and thought to myself, “Right, this is the sound that made me fall in love with music in the first place. Let’s cheer up and get back to it.” And that’s how this song was born.


Thankfully, my song was featured on the front page of the Latest Music section on Korea’s streaming platform, Bugs.

It was also showcased by 821 Sound, where I had it mastered.

I’ve always been a fan of Director Namwoo Kwon’s mastering work—it suits my taste perfectly every time.


These days, I sometimes feel like releasing my own music is just a form of self-satisfaction. Of course, it’s exactly this kind of satisfaction that motivates me to keep making songs.

As time goes on, I find myself letting go of my ego little by little and viewing things from a broader perspective.

This winter, I’m planning to write another book, wrap up my overseas research papers, and submit them for publication.

Let’s keep striving forward!

See you in the next post. 😊

Record Before Modifying the Stam Audio SA-2A

Hello, this is Jooyoung Kim, mixing engineer and music producer.
Until a few days ago, I was planning to sell my Stam Audio SA-2A second-hand and purchase a product from a Japanese brand.

However, it didn’t sell easily, and with the sudden rise in the Japanese yen… So, I decided to modify the unit myself instead of selling it.


Identifying the Problems

Here are the issues I identified with the SA-2A:

  1. Dissatisfying Sound
    • Excessive saturation and dull highs give the audio a muffled feel.
  2. Gain Parameter Adjustment
    • The output volume only matches the original level when the Gain knob is significantly reduced.
  3. Peak Reduction Sensitivity
    • Compression only activates when the Peak Reduction is turned up considerably.
  4. Limit and Compress Switch
    • The switch works in reverse.

Initial Steps in Modification

Addressing Problems #2 and #3

  • Inside the unit, I found a variable resistor labeled A100K.
    • This logarithmic resistor seemed unresponsive at lower ranges.
    • However, since we perceive audio in dB, it made sense to use a logarithmic curve for the Gain control.
  • I decided to replace:
    • Peak Reduction with a B100K (linear) resistor (ideally A200K, but it was unavailable).
    • Gain with a lower resistance A50K resistor.

I placed the order for these parts and will replace them soon.


Fixing Problem #4

  • The Limit/Compress switch was simple to resolve—just unscrewed it and rotated it half a turn.

Investigating Sound Quality Issues

The core problem remained the sound quality. After extensive research:

  • I contacted Stam Audio for the circuit diagrams.
  • I emailed Cinemag, the transformer manufacturer, to get specifications for the input/output transformers:
    • Input: Cinemag CM-5722, winding ratio 1:5.
    • Output: Cinemag CM-2570, winding ratio (18:2):1 = 9:1.

While considering transformer replacements (e.g., Sowter), I found several insights:

  1. Cinemag’s CM-5722 input transformer is already highly rated and doesn’t need replacement.
  2. Discussions on Gear Space suggested that tubes or the T4 cell impact the sound more than transformers.
  3. A post from 2016 or 2017 on Gear Space mentioned that replacing a single input tube can significantly improve sound.
  4. A YouTube video comparing various 12AX7 tubes on a Marshall amp highlighted sound differences between tube brands.

From this, I concluded that the JJ Electronics 12AX7 (ECC83) used in the V1 position is likely the main culprit behind the sound I dislike.

Based on the video, the JJ Electronics tube produced a tone that immediately felt off to me.


Planned Tube Replacements

I decided to replace:

  • V1 Tube: JJ Electronics ECC83 with Mullard 12AX7, a sound I much prefer.
  • V4 Tube: JJ Electronics ECC83 with another Mullard 12AX7 for consistency.

However, due to unexpected expenses this month (e.g., AES membership fees, domestic conference fees, paper review fees, and repairs for another compressor), I’ll postpone the tube replacement until next month.


Side Discovery: DIY Compressors

While researching, I stumbled across a site selling DIY cases and PCBs.

https://collectivecases.com/

While there are plenty of LA-2A clones on the market, the PYE compressor clone caught my eye.

  • PWM-based compressors are rare, and even the clones are scarce.
  • The original units are prohibitively expensive.

Although the schematics look complex and sourcing components would require significant time and money, I feel deeply drawn to this project. Maybe someday, with enough budget, I’ll take it on.


For now, this concludes my record of the SA-2A before modification. Once I replace the tubes and complete further changes, I’ll share my experiences and the sound improvements in a follow-up post.

See you in the next update! 😊