I often wonder why watts are the standard way we talk about amp volume if it's true that wattage, voltage, rectifier, transformer and speaker efficiency all effect output volume. This is compunded by the "difference" in perceived volume when comparing solid state, tube class AB and tube class A "watts." Matchless watts are loud, Peavey watts are not. Mesa watts are loud, tweed not so much... etc ad nauseum. Wouldn't it be more usefull to speak about db's (decibals)? I'd like to know how many db's I need: - until i'm too loud in a living room/bedroom - to jam jazz and hang with drummer and sax - to hang with piano in small space - to play small club (no mic) - to play church - to hear myself from 10 feet with a good monitor mix, and also without ANY monitors - to blast fusion or rock with powerful drummer - to fill a big club (no mic) - to be heard on a big stage - before I hurt my ears - before I hurt the audience's ears - to have good tone I don't understand: is db a measure of sound pressure (at the ear), not output power (at the speaker), and if so, is distance and size of room a factor? Hmm... I know that we usually think this way: - bedroom: 1-5 watts - rehearsal in small room: 7-12 watts - small club, quiter drummer: 18-22 watts - medium club, average drummer and thumpin bass, or clean jazz: 30-40 watts - loud rock: 50 watts - deaf, no PA, trapped in '69: 100 watts - silly: 150-200 watts That works, when we also factor in solid state, tube, class, room, band members, headroom, speaker efficiency (and number), etc., then maybe db's are a more usefull way to approach it? I think I no longer care about wattage; I care about db's: how many db's before breakup? How many db's compared to other instruments? how many db's preferred listening in various rooms? etc. I know my mastering engineer recommends listening at 89db, no more (hurt ears) or less (lose fullness). Watts vs. db's. Please share your thoughts. Thanks.