Over the past few weeks, I’ve encountered a mysterious stranger.

I’ve spent considerable time with this guy since we first met, but I’m having a bit of trouble learning to understand him.

That’s because the stranger is myself.

It’s not the self who’s writing this column, but the self I was about 30 years ago. I’ve learned something about him I just don’t understand.

Don’t get the wrong idea about this difficulty. I haven’t flipped my lid or anything. I’m not talking to myself — at least not any more than usual — and I’m not looking in the mirror and wondering who I am.

But this stranger has some really different tastes in music, much different than I would have guessed, and which I’m still struggling to understand.

The problem started when I was able to restart a project I had begun around 1990 and then, for reasons related to technology and time, I abandoned. I had taken advantage of a new computer’s capability to, with the help of the right software, digitize the music on my old LPs and burn them on to CDs.

I began by converting the music I had enjoyed during my high school and college years, which, unlike most of my peers, included very little of the rock music of the era. Consequently, I ended up making discs of music from Broadway and the groups from the folk music craze of the early 1960s. Next I converted the easy-listening music that was popular while I was courting my wife and during our early married life.

That was when, for reasons of technology and availability of time, I stopped converting music.

Recently, after another computer change and the discovery of better software, I revived my efforts to digitize my LPs, and by now I was able to bypass the CD and put the music directly into iTunes.

At first I found a number of concertos, sonatas and symphonies and names like Telemann, Copland and Mozart attached to them, reminding me that I had been a classier collector of music then. There were also names like Grover Washington, reminding me that I become more jazzy as a listener.

But then, I ran into this stranger. I found, behind an album of music by French composers, an album by ABBA.

ABBA? Could I really have purchased an ABBA record?

Looking a bit further, I found some albums by Lou Rawls. I could account for a couple of them because of that jazz gene I knew I had, but one sounded a bit disco-y. Did I really buy a record like that?

And three Neil Diamond albums? Neil isn’t bad, but did I really buy three albums, especially the one on which he did a duet with Barbra Streisand?

Naw, that couldn’t have been me.

Who, then, was this guy who wormed his way into my record connection sometime during the 1980s?

Well, I still haven’t found answers to those questions, although I have begun to suspect that it had something to do with having a daughter in middle school about that time. Anyway, I’ve decided he isn’t such a bad guy. Simon and Garfunkel’s Central Park concert album was apparently purchased during that time, and I really like the cool Grover Washington jazz. If the trade-off is having that stranger bring in a couple of extra Neil Diamond albums, I can live with that.

But I’d still like to know why he bought that ABBA album.