Hi guys, I'm new at TB. My amp (Ashdown t15-250s, ASHDOWN T15-250S BUNDLE - Thomann UK Cyberstore) sounds pretty muddy. My question is how can I improve its sound? By replacing the speaker (I'm thinking about an Eminence Legend CA154 15" speaker)? Or by adding a cab? I mostly play stuff like Tool, Iron Maiden, Avenged Sevenfold, etc., and I need a growly sound. Thanks in advance.