We mentioned in an article 3-1/2 years ago some problems we had with the D string cores of the JM11 flatwound mandolin strings we've offered through the website for quite some time now (see JM11 String Consumer Alert). Despite a very clean record with nearly 1000 sets since, the problem with the handmade string has intermittently re-emerged. We've had a handful of such reports the last couple months and in the pursuit of maximum quality control, we're publicly registering the concern again.

We don't want to start a panic--it's not a frequent problem, but for those are baffled by immediate intonation discrepancies on the D, it's not the instrument, it's the string, completely undetectable until the string is installed. The manufacturer has equipped us with free replacement strings.

What is happening is in manufacturing, some of these were wound imperfectly at the loop, ultimately affecting the string's core, making it impossible to intonate correctly up the fretboard. Unfortunately, the flaw is undetectable to the eye, and only manifests itself when fretting the new string past the 6th and 7th frets. They can almost be a 1/2 step flat up at the 12th fret.

We've enjoyed tremendous success with the JM11 JazzMando flatwound strings made by Labella, having recently expanded to the JD13 mandola version, and last year, the JM10B ball-end electric mandolin. We continue to try to improve the product, including making adjustments to the length of the playing area (between the silk windings) and reinforcing the loop on the .011 gg E string.

The D-string problem will show immediately once tuned. (It's not a progressive problem.) If you do notice this, let us know. These are still a terrific string and quite popular; we've shipped them though out the US and Canada and to many corners of the globe. We intend to go the extra mile and work with the manufacturer closely to keep them that way.

Let us know (see contact) when you ordered the strings if you run into this isolated incidence.

Posted by Ted at July 16, 2012 5:47 AM