Ask an expert: Infinity tonearms

Good afternoon. I am curious about Infinity tone arms. Is there any info you can offer please?

Certainly. The first arms that the company sold were actually Infinity branded versions of the Forrmula 4 Tonearms but in the late 70's it introduced a pivoted arm of it's own manufacture that featured a carbon fibre arm tube constructed out of the same carbon fibre material as the linear tracking arm on the The Infinity Airbearing Turntable, it is called Black Widow and is now considered something of a minor classic. It's a normally pivoted arm but features a very rigid low mass arm tube and is designed to mate with low mass/high compliance MM carts that were very popular amongst USA audiophiles in the 70's, it features a adjustable anti skating and an oil damped arm lifter and at the leas some (all ?) models featured an adjustable VTA. It is noted that late 70's models are marked just Black Widow but early 80's models are marked GF but there is no clear clue as to what the difference is, the same goes for the Mk II model that was introduced in the early 80's.

The Black Widow technical specifications are : Effective length : 237 mm. Total Cable Capacitance : 60 pF. Pickup Balancing Range : 4 to 8,5 grams. Offset angle : 21,017° (optimal 23,221°). Overhang : 14,359 mm (17,477 mm). Null Radii : 60,00 / 110,00 mm (opt. 66,04 and 120,9 mm).