So my band is starting to play larger gigs in rock bars and pubs currently im using a Fender Mustangs but think its time to.upgrade to a head and a cab. Been looking at the tiny terrors are they loud enough for medium venues?

Budget £800
Music - Grunge
depends on how loud your drummer is and if you get mic'd. i wouldn't be inclined to try to fill a medium sized room with no PA with just 15 watts
Depends on the speaker cab you choose and your band volume. I gigged with one for a while and thru a 1x12 it was just loud enough to run with the drums. Plenty for most pubs and juke joints. If playing outdoors we just mic'ed everything.
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"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

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Ive been use a Fender Mustangs 3 at the moment but want to.get away from modelling amps
Grunge.... hmmmm... Laney AOR 100. Should be a few of those floating around on your side of the pond.
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fender blues deluxe reissue/fender hot rod deluxe would work great. for grunge all you need in a tube screamer or an overdrive pedal to get the sound you want.
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yes it will be. most amps over 10 watts are loud enough to gig with depending on the design ans the speaker setup. speakers matter a lot.

however, 15 watts will not leave you much clean headroom. if you need cleans, may not get there, or leanr to use the guitar volume knob, boosts, etc to manipulate the crunchiness. which really can be a GREAT way to go if thats what you want. or, doesnt it also have a line out? then it also doesnt matter.

clean headroom and response, amp design and type are what wattage resvolves around, not loudness or gig worthiness. if you took that orange and played it through a 2x12 with eminence wizards (very loud speakers in general), it would be a very loud setup. even at 10 watts. stuff like that.
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