(current as of October 5, 2019)
First off, let’s clarify the range of a vibraphone:
Note that the marked extended range (C3 – C7) is not a commonly found instrument, and it’d probably be wise to write in the standard range (F3 – F6) unless you are writing specifically for a person/group that owns an extended instrument.
Now, how do we notate bowed vibraphone? There are two right answers, both of which are simple and familiar to anyone who has written for string instruments. The first, a simple technique marking specifying “Arco”. The second, an up bow marking above the bowed note.
If using the former, be sure to instruct the player to go back to mallets when/if necessary. This could be helpful for clarity even with the up bow marking.
Any two notes can be bowed simultaneously on a vibraphone; on the base level, it’s very simple. However, it’s important to consider where the performer is going to or coming from when considering how comfortable or possible the notes are. The most important thing is to consider is the motion required from moving between the naturals and accidentals; moving a bow over the instrument, especially a full sized bow, is a naturally clunky process. Parts requiring a swift motion in this fashion is a recipe for missed entrances, extraneous noise, and other mishaps. To illustrate this, see the below example demonstrating a good and not so good progression using an f minor 7 chord.
In the first example, the hands are able to move just a fourth or 5th without switching sides. The second example, while the intervals are closer together, would require both hands to swing over the instrument to attack the second chord, which is asking quite a bit without ample time between notes. It’s not impossible for the hands to remain on their respective sides and have the hands cross for an interval as small as a third, but it’s rather uncomfortable.
Don’t forget, a bowed vibraphone won’t make sound unless the pedal is down! This is especially important to consider when writing for a setup that includes kick pedals, electronic pedals, and/or page turn pedals.
Beware the setup!
Large setups can create all sorts of hinderances for bowing vibraphone. It’s important to draw a possible setup to make sure every note written is possible. For example, a part that demands instruments be placed on the accidental side of the vibraphone will make it close to if not totally impossible to bow notes on that side of the instrument. This is especially true if a marimba is “stacked” above the vibraphone, as it will most likely cover the entire instrument. Crotales are also dangerous territory, as their might be desire to both vibes and crotales.
One bow, one mallet, one hand
It’s tricky, but entirely possible to play with one mallet and one bow in the same hand. The two cannot be used simultaneously, but rotating between the two is no issue.
A note on orchestration
While there is a decent dynamic rang that can be achieved while bowing, the ceiling is rather low; when writing for ensemble, consider that a bowed vibraphone, especially in the lower range, will have trouble cutting through the texture without amplification.
Steve Reich — Sextet, Mvt. 2
Christopher Deane — Mourning Dove Sonnet
Elliot Cole — Postludes