It looks possible. Look at the airtime.conf file. The documentation mentions a handy command (airtime-update-db-settings) that updates "all of Airtime's database configuration files". They recommend you run this command if you modify the [database] section of airtime.conf
Wade is totally right; beyond that, you probably should have the database served from another server.
This goes past just avoiding a ddos; you can then have a standby airtime server in case your primary goes down, if you run a load balancer in front of airtime, you can set sticky sessions on the LB, and let the LB handle failover - or use heartbeat, but I prefer letting the LB do it...
TL;DR: you should put the db on a different host and try to perf tune it.
There's absolutely no logical or technological reason to intentionally separate the Airtime UI from the DB or LS. None. Zip. Zero. Zilch. Nada.
If anything, Icecast could (and should) be separated to keep your Airtime server from becoming a lightning rod on the public Interwebs. But even then, if someone nefarious really wants to attempt to DDoS your Icecast box, they're going to do it.
And at that point, under serious attack, your upstream provider is likely to notice and take the appropriate countermeasures with or without you.