So my band has 2 shows in the coming months and we are in need of a bass player and a singer. We kicked out the singer about a week ago.

If we don't find them in time we still plan on playing, just wondering if that might hurt the reputation at the place we play, they said they liked our sound and we can play anytime we want, and we got the gig 10 min before we kicked our singer out, so it was a surprise.

It seems a good bassist is hard to find.
I'd definitely place bass as the higher priority, unless your last vocalist was phenomenal and that's what got you the reputation. Try looking up ads on Kijiji or Bandmix.
To be frank, i loose interest in all completely instrumental rock music after about 2 minutes, except if its really good. Even then i get bored easily, and its similar woth all my friends. And i agree, get a bas player first, one of you can also sing if a need arises. Of course, whats keeping you from looking for both at the same time?
Joža je kul. On ma sirove z dodatki pa hambije.
Unless you've built your fanbase on being instrumental I wouldn't bother. Also if you don't have a bassist either the whole thing is just going to sound empty and people will lose interest even quicker. I'd call them off till you guys have your stuff altogether.
Basically what everyone else said. I would call it off. It's better to call of a show and keep your fan base than play a crappy one. But let the promoter know now. The sooner you do it, the less mad he'll be.
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