In the context of Musicians of the Old Post Road’s  “Now and Then,” an exploration of historical instruments and their modern counterparts in music by Bach, Couperin, Mozart, and other masters inked for this Friday in First Parish, Sudbury, a player and BMInt writer philosophizes.

Imagine, if you will, an early-music chamber ensemble with a consort of 20^th-century instruments in their hands. All that wire and varnish and velvet! Imagine a group that had always worked together using the rhetorical playbook, making decisions about how to perform Couperin while suddenly armed with equipment that could belt out Reich or Schnittke. How, precisely, does that make you feel?

When the Musicians of the Old Post Road finished up last year’s 25^th-anniversary season, the programming that followed was imbued with a sense of lightness and experimentation; time to take new risks! So the group decided (why not?) to begin its next chapter by gently poking an 18^th-century bow into one of the most active hornets’ nests that exists for a period-instrument ensemble

What does it really mean to play on a historically styled instrument?
How does it really compare to playing the repertoire on modern instruments?

We all know the party line; playing on ancient equipment opens us to revelatory new possibilities in sound production and phrasing. Everyone who has ever picked up a baroque bow and experienced that initial double-take at the delicious lightness of the tip knows that this argument is valid at the core. And yet most of us have performed plenty of beautiful Bach suites on steel strings with heavy bows and coached truly lovely Vivaldi sonatas accompanied by piano. So, what’s that all about?

The question of historical models and their effect on style is not going to get answered in one evening’s worth of music. Yet perhaps it can be asked in a more pertinent and pointed way.

In this program, a simple back-to-back comparison serves as the first line of questioning. A Bach trio sonata, a Couperin passacaille, and the Mozart D Major Flute Quartet will all be allowed to “speak” for themselves, each played on an early and a modern set of instruments (including a grand piano filling in keyboard continuo.)

We’re all accustomed to switch from modern to early, but now, go back to that opening scene: the members of a period ensemble pick up modern instruments to play together; instruments that they are all familiar with individually but that they had never used in each others’ company before. That’s a more interesting and thorny tableau—one where all the questions about performance practice get turned on their heads.

Hmmm, what about vibrato? The chinrest certainly makes it easier.
These long bows sustain a whole lot—how should we react to that sonic fact?
How’s the balance working between us with all these steel strings?

It’s both hilarious and strikingly illuminating, and it required coming up with a whole new set of artistic rules. We had to consciously decide in every case; should we keep as close as possible to the “old” phrasings and interactions, working extra hard on the new instruments to reproduce those sounds? Or should we let the new instruments run wild, and revel in long swells and warm vibrato?

In the case of the Couperin, the group found an early 20^th-century version of the work, complete with sumptuous dynamic colors. It was too tempting not to attempt a form of historical re-enactment on it, and so it is being played “as is,” every passionate crescendo in place, on the program. On the other hand, the Mozart Flute Quartet is being performed in as close to a historically informed style as possible, which means a lot of extra work from all the players to use the capabilities of the modern instruments to echo the old ones. And these are just two of the simplest ways to traverse the stylistic minefield!

How does one end an evening like this? We chose to move all the way to the other end of the spectrum and commissioned a brand-new work, written specifically for period instruments, from composer Carson Cooman. If the question of how to play “old” music on “modern” instruments is rich with layers of stylistic implication, the question of how to write music, today, for period instruments is even more splendidly fraught. Of course there are many different responses to that challenge, and Cooman’s is fresh, bright, and stylistically gracious—and paradoxically, is linked to a style of music even earlier than that of the rest of the evening. To write anything else about it would be telling.

A popular wayside pulpit quote reads: “Unanswered questions are far less dangerous than unquestioned answers.” It is likely that this evening’s entertainment may raise more questions than it purports to solve. If musicians and audience members alike leave the hall feeling newly equipped to wrestle with valid, thorny, issues, then that would be an ideal outcome.

Sarah Darling, a violist with A Far Cry, pops up anywhere and everywhere around town in early, classical, and contemporary circles.