The Amazing FET Circlotron Construction, Continued — Michael Rothacher / 2008

A lot of would-be audio projects die on the vine, even when printed circuit boards and components are readily available. The planning, layout, and construction of the chassis metalwork are sometimes the barrier. Perhaps, this is why complete kits are often the first choice of beginners. To get you building, I’m including some additional information, a few instructions, pictures, and a parts list. Wherever possible, I’ve tried to select suppliers who have online stores so you can just “click” your way to a complete kit of parts. The Chassis To simplify construction of the FET Circlotron we’re going to go… More...

Phase -Coherent Crossover Networks — Nelson Pass / 1982

The importance of phase response in the audio chain has been brought to greater focus recently by equipment claims of phase coherency, (the output signal has the same phase relationships as the input signal). It is not particularly obvious that two different frequency components of a signal can go into a device at precisely the same time and emerge at different times, but it is extremely common. All audio components distort the phase of the signal to some degree-even air alters the time alignment of a signal, but the biggest offenders are loudspeakers and their crossover networks. Phase shifts in… More...