Tonight we held a marathon acoustic Arcati Crisis rehearsal with the addition of our old friend and new bass man, Jake.

As we learned last year with Zina, it’s not the easiest thing to onboard a new band member – even when they’re the most instinctual player and consummate professional. As the bandleaders, we have to know our stuff cold. Every rhythm, every transition. Anywhere we’ve developed a bit of sloppy shorthand with each other will fall apart when the new instrument hits it – especially with the force of Zina’s drumming!

As opposed to Zina (who started from just two songs that had drum arrangements and learned our entire repertoire in eight months), Jake has the benefit of existing fully-notated arrangements that imply a certain amount of bass action. Sounds great, right? Yet, Jake has both Gina and I competing with him on low end rhythm, because at many points we act as each other’s bass player.

Two steps forward, two steps back.

(No, that does not mean we’re covering a Paula Abdul song. If only. I’ve proposed that cartoon cat action at least once a year.)

(Also, FWIW, bass isn’t as obvious as drumming or adding harmony. A new bass part can sound perfectly fine for weeks until it’s turned up just a touch, and you realize it actually clashes with everything.)

Last week we learned out of the blue that we’re responsible for a three hour long acoustic spot next Saturday in Collingswood, so Zina got the night off while we attempted play every song we can even vaguely claim to know – which turned out to be 30 – with Jake playing bass on as many of them as he was able.

To put that in perspective, on the current never-ending U2 tour that boasts different setlists every night to date they’ve played a total of 61 full-length unique songs, along with a vast number of medley’d snippets.

Three hours later and I am completely spent – mind, body, and voice.

I fundamentally don’t understand how bands keep more than 30 songs in repertoire. Even rehearsing two or more times a week, it’s just a monstrous amount of material to keep fresh.

Of the 30 songs we eeked out around 25 solid versions – most with Jake. The giddiest success was “Better.” After weeks of misses and curses-under-breath, we nailed 11 out of twelve three party harmonies. We finally clicked on “Brother John,” “Real End” has transformed (again) into our best pop song, Gina and I delivered a close to note-perfect “In My Life,” and Jake made “Under My Skin” giddy and new again.

(What were the seven bum tunes? Mostly covers, though we fell apart repeatedly on “Hyperbole.” Specifically, we bombed “Total Eclipse of the Heart,” and I was overwrought and flat on “Across the Universe.”)

We have one more three-hour rehearsal left, and then our show. I’m sure we’ll be fine – after all, we’ve done this three-hour thing before, and we had a lot fewer songs back then. But it will also be our first trial-run with Jake helming our low end. It sounds fine in our parlor, but who knows how it will turn out in the wild?

Also, it makes me wonder how we’re going to achieve on of our big goals for the 2011-12 season of AC – learning a new song every month. Are we really ready to be rehearsing 44 tunes by a year from now?

I guess we’re about to find out.