Hi,
Each channel powers four .9 ohm coils in series. They are each composed of about 125 feet of #18 enamel wire.
You haven't indicated the
purpose of the "coils" nor even if they are optimised to maximise or minismise their inductance (and/or the magnetic field that they produce). What are their dimensions and are they wound on a "magnetic" core? Are you perhaps trying to transmit energy? If so, you should probably be using a (Radio) "Transmitter" circuit not an (Audio) Amplifier (but beware that there are many wireless transmision regulations that
should not be "illegally broken", for any frequency above 16 kHz ! ).
There are also many "Laws of Physics" that
cannot be broken. I don't have time to write a complete electrical engineering training course, but:
.... my beautiful Simpson analog ac amp meters in series with the coils read a power loss as the frequency varies above or below 60 hurtz.
A meter connected in series with a Load can only measure current (Amps), it
cannot measure "Power". Similarly, a meter connected across a Load can only measure Voltage, again it cannot measure "Power". However,
IF the "Load" is a
Pure Resistance, then you can use Ohms Law to convert between Volts and Amps (i.e. R = V / I) and then can calculate the Power in the resistance as P =
V2 / R or
I2 * R . A fundamental characteristic of an Inductor (e.g. a "Coil") is that its impedance increases with frequency, so for a constant voltage drive, the current
must fall as the frequency rises.
Capacitors and Inductors do not dissipate "Power", but they can Receive, Store, Convert (e.g. to mechanical movement) and Transmit it (e.g. via a magnetic field) in specific circumstances. Their characteristics (i.e. behaviour) is highly dependent on the frequency applied (i.e. at "d.c" a capacitor behaves as an "open circuit" and an inductor as a "short circuit"). Resistors are rather a "special case" in that they can
only receive power and convert it to heat (at d.c. or at any a.c. frequency).
But no electronic components are absolutely "perfect" (or pure): Resistors can be "very good" (pure) but at (very) high frequencies may exibit some inductance (e.g. a wire-wound resistor). Many Capacitors also can be very good, but ultimately may exhibit some inductance (if only of their connecting leads) and/or "leakage current" (e.g. of Electrolytics). However, Inductors are often quite "poor" because they will always have some resistance, so (IMHO) should be specified in terms of their units of "(micro/milli-) Henrys" and their Equivalent Series Resistance (in Ohms). Therefore, Inductors should always be considered (if not actually drawn in a circuit diagram) as being connected in series with a resistor.
The next step in development will be to tune the coil sets to various frequencies.
Fourier discovered that any electrical or audio waveform can be considered as a combination (or "series") of Pure Sine Waves, typically the "Fundamental" frequency and some/all Integer "Harmonics", for example a square wave contains all Odd Harmonics ( i.e. F , 3*F , 5*F , etc.) and Sawtooth/Triangle waves contain Odd and Even (i.e. F , 2*F , 3*F, 4*F , etc.) in reducing amplitude at higher frequencies. Basically, a "Tuned Circuit" will tend to select out the nearest "Harmonic Frequency", with the/a Capacitor becoming dominant at Higher Frequencies (i.e. approaching a short circuit) and the/a Inductor dominant at Lower Frequencies (i.e. a short circuit, in series with its resistance).
Note that a "Parallel Tuned Circuit" driven by a constant voltage at increasing frequency, does NOT increase the (coil) current, it simply reduces the load on the drive circuit. To "maintain" the current magnitude, the voltage across the coil must be increased, which
can be achieved by using a "Series Tuned Circuit": This can generate an enormous voltage (at the junction of the C and L), so you must ensure that the capacitor is adequately rated (e.g.
1 kV at the desired frequency). But beware that at "Low frequencies" the capacitor dominates, so it becomes simply an "Open Circuit Load".
Cheers, Alan.