Who is the most underrated composer? A case could certainly be made for Luigi Boccherini, whose Quintet in D major, Op.43, No.2 was given a richly burnished reading at Merkin Concert Hall on Sunday afternoon by the stellar chamber group Concertante. Not that there are a lot of Boccherini haters out there — I have never actually met any — but his music seems to be treated primarily as wallpaper by concert venues and FM radio broadcasts. Hearing him performed so expertly and lovingly this weekend, however, made me remember how deeply satisfying and magically melodious his music really is.

Concertante is a protean chamber ensemble springing from a core sextet (Xiao-Dong Wang and Ittai Shapira, violins; Ara Gregorian and Rachel Shapiro, violas; and Alexis Pia Gerlach and Zvi Plesser, cellos), which played from its opening passages music of a high quality and a remarkably woody sound. Listening to Boccherini played this well was similar to hearing a great Cremonese stringed instrument, forcing the listener to redefine his or her notions of what is great and what is merely acceptable. I have been listening to these folks for years — this is, in fact, their tenth season at Merkin — and seldom have I heard them sound more superbly blended.

The ensemble’s latest project, a commissioning effort titled “One Plus Five,” is a multiyear blueprint for six world premieres composed for the group’s particular instrumental configuration. Each new piece will feature one of the six core members, with the other five playing, well, concertante. Prospective composers include Tigran Mansurian, Gabriela Frank, Shalumit Ran, Richard Danielpour, and Kevin Puts. First up is Lowell Liebermann, who offered his Chamber Concerto No. 2, featuring Mr. Wang. Strictly speaking, the world premiere was Saturday evening in Harrisburg, Pa., but, as we all know, the real premiere was right here in New York.

The piece is an elegiac essay with quite a bit of heartfelt material. The vocabulary is stretched tonality, and Mr. Wang made the violin solos soar by layering on a generous dose of vibrato. The underlying material was a rather uncompromising and relentless lamentation that sometimes reminded of a Shostakovich string quartet. Certainly the six played with a great deal of emotion.

It was fortuitous that Mr. Liebermann was not in attendance this day, for, although he missed what is almost undoubtedly the finest performance that his work is ever to receive, he also missed his painstakingly constructed ending ruined by the ringing of a cellular telephone. That infernal device could not have gone off at a more disruptive moment.

About a year ago in these pages, we discussed the dearth of British music performed in New York. In two recent seasons, not one single orchestral piece from 20th–century England was offered here, even though several of the visiting ensembles were from the United Kingdom. Now, as this season dawns, I am delighted to report that the magical Piano Quintet in A minor of Sir Edward Elgar from 1919 is scheduled twice, once in February by the Chamber Music Society of Lincoln Center, and the other on this program.

The work is atypical Elgar, full of, in the composer’s own words, “ghostly stuff” and jazz influences. Much has been made of George Bernard Shaw’s espousal of the piece, a phenomenon that I find ironic, since the style is very heavily Brahmsian. For this performance, the dominant piano part was intoned majestically by Anton Nel, with Mr. Shapira in the first violin chair and Ms. Shapiro and Mr. Plesser joining Mr. Wang.

This was a magnificent performance. Not only did the group capture the dramatic power of the piece, which Elgar engineers through rather thick, orchestral-style textures, but the musicians were extremely sensitive to the individual melodic bits, in a similar manner as they had demonstrated in the opening Boccherini. I have never heard these snippets performed quite so lovingly. One particular theme in the Adagio is introduced by the viola, and then taken up in turn by cello and second violin. Hearing it in this setting was almost polymorphous perversity, so delicious was the sonic result. Perhaps American interest in the rich music of the English renaissance will grow significantly if we continue to hear performances like this one.

So who is the most underrated composer? Personally, I love the answer of Professor Peter Schickele, who responded Mozart. Yes, Mozart. Why? Because even the highest possible rating is still a gross undervaluation.