Eric,
Speaking length of the string is equal to the scale of the instrument: ie: 32 short scale; 34 Long scale; 35 + extra long scale, etc. The Alembic bridge and tailpiece adds about an inch to the overall or Total string length, which is longer than a standard Fender style bass with Bridge-tailpiece combo. Also, most Alembic headstocks are quite large, and may typically be a bit longer than other brands. You should check with the string manufacturer for speaking length and total string length specifications. Also, definately measure your guitar for these 2 lengths (especially the total length) to see if there is a concern. On my Series 1 4 string, I had a few brands where the E string was a bit short, and the silk wrap at the tuning peg would ride in the nut. I would try to unwrap a bit for better string/nut contact. Similarly, the A and D string could have been 1/2 longer to get 3 wraps around the tuning peg, and I had to settle for one and a half turns. For me 3 wraps around the peg works best. At 1 1/2 turns, the string would detune fairly easy with a good slap or vibrato. Check string documentation. Some manufacturers will show a range (ex: 34 ~ 36 speaking length for extra long gage). In any case, you should be able to measure the string at the store or even lay it on your guitar to make sure it is long enough before committing to the purchase. Once it's cut and tuned, it's yours! (P.S. Alembic strings work on Alembic guitars!)
Kris