haveyouheard

The volume to watt ratio changes depending on if you're using a tube or circuit amp. If you're using a tube amp then 30watts is more than loud enough for 500 people. You could even go with 15. My Vox AC-30 will self destruct and bring the club with it if I crank it.

If you go with a circuit then you would need around 100 - 150 watts.

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-Adam Trimble
Co-host of the weekly music review podcast Have You Heard.

GuitarBizarre

1 - you mean tube or solid state. both are 'circuits'
2 - Its nothing to do with that really. 30 output watts is 30 output watts.
3 - Loudness is dependent on wattage and speaker sensitivity. a 90db speaker is twice as loud as an 87db speaker.
4 - Tube amps tend to sound louder because they have certain characteristics and many are designed to be pushed over maximum to gain power tube distortion. hence on a lot of amps, 30 watts is the maximum it can handle completely clean. it might go as much as another 5 watts once power tube distortion hits.


For these reasons tube amps seem louder than solid state at similar settings. seem being to key word here.

In a more practical sense however, my solid state Line 6 X3 sounds ****ing amazing, and I could easily run the line out from that through a 1000 watt behringer poweramp module into a homebuilt cab. And it would have still only cost me as much as a medicore halfstack while sounding a hell of a lot better and more versatile to boot.