jeongho

🔗 tinyurl.com/tube-cascade-mod

Multiplicative Tube Harmonic Processing: A Modular Architecture Discovery

How cascading independent tube buffer components creates superior harmonic complexity

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The Accidental Discovery

jeongho

🔗 tinyurl.com/jp-reference-track

Ultimate Audiophile Reference Playlist

A carefully curated collection of 22 reference tracks for evaluating audio equipment, organized by sonic characteristics and musical genres.

Vocals/Jazz

1. "Spanish Harlem" - Rebecca Pidgeon (The Raven)

• Test for: precise vocal imaging, microphone quality

jeongho

🔗 tinyurl.com/audio-opt-90-10

Audio Optimization Algorithm

How I applied mathematical optimization to solve the audiophile value problem

Note: Pricing as of June 2025

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jeongho

# haproxy -v
# HA-Proxy version 2.3.14-83c5b44 2021/09/07 - https://haproxy.org/
# Status: stable branch - will stop receiving fixes around Q1 2022.
# Known bugs: http://www.haproxy.org/bugs/bugs-2.3.14.html

# Self-signed SSL certificate
# https://gridscale.io/en/community/tutorials/haproxy-ssl/
# openssl req -nodes -x509 -newkey rsa:2048 -keyout /etc/ssl/private/test.key -out /etc/ssl/private/test.crt -days 3650
# writing new private key to '/etc/ssl/private/test.key'
# -----

jeongho

--# postgresql 12 high availability cookbook ch14: creating a scalable nextval replacement
--## this example has 2048 shards (schemas) and 2048 unique values per millisecond (seq % 2048)
--# ref: [Sharding & IDs at Instagram](https://instagram-engineering.com/sharding-ids-at-instagram-1cf5a71e5a5c)

CREATE SCHEMA shard;
CREATE SEQUENCE shard.table_id_seq;

CREATE OR REPLACE FUNCTION shard.next_unique_id(
	shard_id INT
)

jeongho

#https://stackoverflow.com/questions/59717111/cannot-generate-native-image-using-graalvm-in-os-x-catalina
sudo xattr -r -d com.apple.quarantine /Library/Java/JavaVirtualMachines/graalvm-ce-java11-20.1.0

jeongho

jeongho

#!/usr/bin/env bash
#sudo apt install uchardet
#sed -i 's/\r$//' convert_to_utf8.sh
#bash ./convert_to_utf8.sh ./t3series-common

[ $# -eq 0 ] && { echo "Usage: bash $0 target_directory (eg. ./t3series-common)"; exit 1; }
[ ! -d $1 ] && { echo "Directory $1 not exists"; exit 1; }

pushd "$1"

jeongho

dig axfr aa05.penguin.antarcticatec.com | grep -v ob | sort | sed -n -E "s/(.*)[0-9]{3,}.aa05.*$/\1/gp" | grep -E "(^ul|^dt)" |sort -u |grep -v CNAME

jeongho

curl -sS --retry 5 --retry-delay 5 -m 60 "http://localhost:8983/solr/admin/metrics" | jq -r '.metrics | tostream
| select(length==2)
| (.[0] | map(tostring) | join(".")) as $k
| .[1] as $v
| "\"\($k)\" = \"\($v)\";"' \
| sed "s/\"//g;s/ms$//g;s/\;$//g;s/ = / /g;s/\//_/g;s/\._/\./g;s/'//g;s/-/./g;s/:/./g;s/\.shard[0-9]*\.replica[^\.]*//g" \
| tr [:upper:] [:lower:] | egrep -v "(rate|ms) " | egrep -v "(\.duration\.|http\.__|handlerstart)" \
| awk '/ -?[0-9]*\.?[0-9]*$/ { if ($1 in keys) { keys[$1] += $2 } else { keys[$1] = $2 } } END { for (key in keys) { printf("%s %s ms\n", key, keys[key]) } }' \
| egrep "^solr.jetty|^solr.jvm|^solr.node|^solr.core.*\.deleteddocs|^solr.core.*\.maxdoc|^solr.core.*\.numdocs" \
| head -n 20