VARIOUS EDUCATIONAL An Audio Obstacle Course - Era III (1973 US 9-track stereo LP test record to enable you to fine tune your Hi-Fi & cartridge & minimise mistracking, sibilance & other distortions by optimising your tracking weight across Low,Mid & High frequency tests, pasted picture sleeve complete with further information insert. The sleeve shows light shelfwear and the vinyl has few signs of play TTR-110)