Added a speaker out/in to my 100 combo. : r/BossKatana
Let's Talk Celestion... Is It worth Upgrading the Speaker on Your BOSS Katana? - YouTube
BOSS KATANA 50 MK II WITH UPGRADED WAZA SPEAKER!!! KILLER!!! | Reverb
Katana 50 stock speakers VS. Celestion GREEN and BLUE - YouTube
BOSS KATANA 50 MK II WITH UPGRADED WAZA SPEAKER!!! KILLER!!! | forum.iktva.sa
BOSS Katana - 50 Mkii Combo Guitar Amplifier, Stage-Ready 50-Watt Combo Amp with A Custom 12-Inch Speaker : Amazon.co.uk: Musical Instruments & DJ
Boss Katana MkII 50 speaker handles low-end poorly : r/BossKatana
Amazon.com: Boss Katana 100 MkII 100-Watt 1x12-Inch Guitar Combo Amplifier Bundle with Amp Cover, Roland Instrument Cable, and Boss Picks : Musical Instruments