Variable Resistance Compound Gauge
Excerpted from Arnold Jacobs: Song and Wind

Before Jacobs introduced these devices to the music world in 1982, he made several devices. As a part of the original studio (around 1960), Mr. Jacobs attached a compound gauge (for both inhalation and exhalation) to an aluminum pipe with holes drilled to vary resistance This is a tool that he used for decades and many of his students have desired this for use with their own students. Working with Mr. Jacobs, we developed the Variable Resistance Compound Gauge using a similar gauge developed for use by respiratory technicians.

The gauge for the original cost over $300 (in 1960). The key to the reproduction was to make it affordable - the primary cost of this tool being the gauge. Rather than developing expensive molds or using computerized lathes, the pipe is hand-made of inexpensive but sturdy delrin. While not having the cosmetic perfection of more expensively produced pipes, this is just as functional at a fraction of the cost.

In the use of the gauge, inhalation should be emphasized for both air volume and time. First, cover the two largest holes and inhale and exhale until the meter shows 40 (inner dial) on both sides. Do this as slow as possible trying to maintain 40. After resting a few minutes (to avoid hyperventilation) cover the largest hole and one of the small holes. Inhale and exhale  until the meter reads 20. Finally, the three smaller holes are covered, exposing the largest and the inhalation/exhalation cycle is repeated. Try to get the meter to 20. The key with these exercises is to concentrate on inhalation which should take as much time as possible before exhalation.

Video - Compound Gauge