The Kleinhorn Part 2 — Nelson Pass / 2004

If you saw part one of this project (AudioXpress, January 2005), you know that the KleinHorn is a big toy, and you can imagine that it’s hard to resist playing with it further. When Chris and Matt built the horns last year, they made different driver chambers and replaceable front baffles, so that it would be easy to try different loudspeaker drivers. In this part we will first briefly explore some of the effects experienced with different amounts of absorbent stuffing in the horn as presented in Part 1. Then I will describe the effort to add scary deep bottom… More...

Current Source Crossover Filters — Nelson Pass / 2004

In today’s marketplace, audio power amplifiers are conventionally viewed as voltage sources, delivering a given voltage at the output that is a multiple of an input voltage. To the extent that they are truly voltage sources, having a very low output impedance, they simply deliver whatever current happens to reflect the response of the loudspeaker to the defined output voltage. Recently I have been playing with current source power amplifiers that have high output impedances and deliver a specific current to the load in response to an input voltage. The voltage across the loudspeaker reflects its response to this defined… More...