(This review is written by American-Statesman freelance arts critic Luke Quinton.)

These days there are so many healthy early music ensembles in Austin that they’ve begun giving concerts in other cities.

Austin Baroque Orchestra’s founding conductor and artistic director Billy Traylor was doing exactly that this weekend, putting his research on display in Austin and San Antonio, with the ensemble’s fourth annual concert unearthing music of Spanish-controlled Mexico, some of which hadn’t been heard in perhaps hundreds of years.

To top it all off, after their Friday show at Austin’s First Presbyterian, Austin Baroque’s San Antonio concert took place at a 260 year old church, Mission Concepción, recently awarded UNESCO World Heritage status, along with the string of San Antonio’s other mission churches.

And it’s easy to see why.

The tumbled limestone towers and walls of the complex are some of the oldest structures in the New World. Concepción was completed in 1755, and walking around its walls before hand is enough to absorb a palpable vision of history.

Mission Concepción in San Antonio

As Traylor explained, this is music from the Spanish cathedrals of Mexico — pictures of the Mexican churches in the program confirmed that they look remarkably similar to Concepción. And the music was pulled out of the past from Traylor’s own research, and with the help of a UTSA music professor and his “Oaxaca box,” full of centuries-old scores that lay all but neglected.

Some of these scores, like Francisco Martinez de la Costa’s “Llegad, moradores de aqueste pensil” were, Traylor says, “almost certainly a U.S. premiere,” and may in fact have been only performed one or two times in history.

Martinez de la Costa’s work was a joyous hymn, reverberating under the small dome of the church’s interior.

Austin Baroque have a vibrant energy, especially from their singers. I counted nine solos by different singers, each one persuasive and technically adept in their own right.

Early on the orchestra drowned out the soloists, as the cellos and violins rang off the stucco walls. And there were some squirrely notes and pitches, though fairly rare.

It was the voices that were most persuasive. The music had a remarkable variety from these singers — an entire counter-tenor solo work, some operatic moments and then — to my ear the best moments — the choir singing at full-voice.

The friendly San Antonio crowd felt slightly unsure when to clap, a rather understandable problem in a piece like Manuel de Sumaya’s “Sequencia de Difuntos” (mass for the dead), which alternated with choral sections, duets and arias, each one like a mini work of its own.

If there’s a complaint here it’s length. In a scholarly rush of enthusiasm, a couple of hours of this music can be too much of a good thing. A more concise program, and removing some repeats, could help the audience focus on the best of this music.

Ultimately it’s been an extremely fruitful vein of research for Traylor and his talented ensemble. Much of this music was absolutely comparable to the counterpart music being made in the old world. By digging through these archives and doing a substantial amount of re-arranging and preparation, Austin Baroque have tapped into an interesting subsection of what is, in one sense, North American Early Music — an intriguing rarity. Now the just have to work out a way to leave the audience wanting more.