THIS PAST SUMMER AFTER OWNING 2 MARTIN D-35'S I HAD AN OPPORTUNITY TO PURCHASE A 1971 MARTIN D12-20, I HAVE ALWAYS CONSIDERED MARTIN TO HAVE VERY HIGH QUALITY INSTRUMENTS. BUT IT DIDN'T TAKE LONG BEFORE I REALIZED THAT IT HAD A SERIOUS INTONATION PROBLEM STARTING AT THE 4TH AND 5TH FRETS. I ENDED UP IN HAVING A COMPINSATED BRIDGE INSTALLED WHICH TOOK CARE OF MOST OF THE PROBLEM BUT STILL HAVE TO DEAL WITH THE 8TH A & 10TH STRING BEING SHARP. I HOPE TO BE ABLE TO HAVE IT CORRECTED AS THELOWER RICH SOUND IS STILL REMARKABLE, BUT IT DID OPEN MY EYES TO SOMETHING I HAD NOT EXPECTED FROM MARTIN DAVE G.