The Wharfedale MACH 9) Some competing loudspeakers sold at the time were the Bose 901 Series IV and V, Bose 201 Series I, Bose Series 601 Series II, JBL Delta, Cerwin Vega D series, JBL Radiance, JBL Sigma, and Acoustic Research AR-58B. The Wharfedale MACH The Wharfedale MACH series of loudspeakers consists of the MACH 3, 5, 7, and 9. This is an informational page devoted to owners and users of these loudspeakers and those interested in history and construction of electronic sound reproduction. These loudspeakers were manufactured at Rank Hi-Fi, Wharfedale Works in West Yorkshire by Wharfedale Loudspeakers in England (UK). They
.17 Mach IV .17 Mach IV The .17 Mach IV is a wildcat centerfire rifle cartridge, based on the .221 Remington Fireball case, necked down to fire a .172 bullet. The cartridge was introduced in 1962 by Vern O’Brien. The cartridge offered an easy case conversion and good ballistics, but could not compete against the .17 Remington. The name, Mach IV, comes from the claim that the bullets can reach 4,000 ft/s. Due to the relatively small case capacity, even small variations in powder of can lead to the difference between a safe and dangerously over pressure load. The .17 Mach IV became