Ron et al. Lyric's, and therefore ML's first product, was, I believe, the LNP-2 pre-amplifier, which showed up during my first year there. It was 1975 or 76, but it could be off a bit. I recall the price was $2500; everyone said it would never sell. As Elliot stated, they flew off the shelf! The Tom Colangelo-designed ML-series amplifiers came a little later, and, of course, the incomparable HQD system. The Boulder of their day would be a fair analogy.
Other exceptional yet very expensive products of the day were the Sequerra tuner and the Nakamichi ZXL-1000 cassette decks, of which we also sold a ton. I'm not sure I agree with them being sold simply because of their high price. All were exceptional products, along with ARC and Jadis electronic, Mitch Cotter step-up transformer, and other exotica. Below is a well-documented history of the early ML products for those interested in delving further.
A History of Mark Levinson Audio Systemsby Chris Bennett and Barr
theaudiostandard.net