Two-headed focusing stethoscope (THFS)

A method for subtracting sounds originating from a first sound source, from a composite of sounds originating from said first sound source and a second sound source, comprising the steps of:

• (a.) positioning two functionally-equivalent transducers so that the first sound source is equidistant from said functionally-equivalent transducers, and said second sound source is closer to one of the transducers than the other transducer,
• (b.) subtracting the signal of one transducer from the signal of the other transducer, yielding a difference signal.
• (c.) applying enough gain to said difference signal so that it can drive a speaker, and
• (d.) transducing the amplified difference signal back to sound, whereby a composite of sounds from two proximate sound sources can be dissected into its components.

An electronic stethoscope, comprising:

• (a.) first means for transducing sound into a first electrical signal,
• (b.) second means for holding said first means, which permits the first means to be positioned as desired with respect to the object of study,
• (c.) third means, which is functionally equivalent to the first means, for transducing sound into a second electrical signal,
• (d.) fourth means, which is functionally equivalent to said second means, for holding said third means,
• (e.) fifth means for subtracting said first electrical signal from said second electrical signal, yielding a difference signal,
• (f.) sixth means for transmitting the electrical signals from the transducers to said fifth means,
• (g.) seventh means for amplifying said difference signal, and
• (h.) eighth means for transducing the amplified difference signal to sound.

An electronic stethoscope, comprising:

• (a.) two microphones which are functionally equivalent to one another,
• (b.) a rigid housing for each said microphone, small enough to be readily manipulated with thumb and forefinger, having a socket to accommodate the microphone, and a funnel which widens outward from said socket, the combination of said housing and its contained microphone being a chest piece,
• (c.) a battery-powered electronic circuit, having two inputs and an output, configured to amplify the difference in voltage between said inputs,
• (d.) a cable, connected at one end to one of the inputs, and at the other end to one of the microphones,
• (e.) a second cable, connected at one end to the other input, and at the other end to the other microphone, and
• (f.) a speaker, connected to said output of said battery-powered electronic circuit by
• (g.) a third cable, whereby the difference between the sounds transduced by the two microphones is amplified and presented to the user.