Korg's DIY headphone amp and overdrive pedal go on sale in February | Engadget
Guitar Pedal X - GPX Blog - Vox's Valvenergy NuTube Mystic Edge AC30 style and Copperhead Drive JCM800 style Overdrive / Preamps are fairly decent budget options for those genres
KORG OD-S - NUTUBE OVERDRIVE KIT guitar effects pedal From Japan | eBay
Ibanez NuTube Tube Screamer Overdrive Pedal
KORG NUTEKT OD-S Analog Drive Pedal: Guitar and synth test // Building the NUTUBE kit - YouTube
Korg Nu-Tekt OD-S Overdrive Kit review | Guitar World
Review] Korg OD-S Nutube Overdrive - YouTube
Review] Korg OD-S Nutube Overdrive - YouTube
OD-S - NUTUBE OVERDRIVE KIT | KORG (USA)
Korg OD-S NuTube Overdrive
Just Sounds: KORG OD-S Nutube Overdrive Kit — Noisegate