Audio Systems: Impedance, Speakers, Subwoofers, Amplifiers

When an install, replacement, or upgrade of a speaker for a PA system, car, or home audio system such as a subwoofer beast like the STW-350F188PR01-04, to any other speaker from our Speaker Category, below tips may help, and hopefully spark some audio conversation for the audio enthusiast.

Choose the correct ohms. You must also use both coils if your speaker comes with dual coils. Dual coils are meant to assist with impedance matching through wiring flexibility and must be utilized in a series or parallel configuration. Wire the speaker(s) to be equal ohms to the amplifier channel(s) as this will provide optimum power. If impedance matching is not a possibility, then wire the speaker to have higher ohms than the amplifier. Just remember amplifier output power will be reduced when having speakers of higher ohms on the output.

When Daisy Chaining speakers together, commonly found in PA systems, you are decreasing the speaker ohms that the amplifier is seeing since this is a parallel combination, make sure you do not go below the ohms of each amplifier channel. Parallel coils= decreased ohms, series= increased ohms. However, since most PA speakers now-a-days are self powered or “active” type, multiple of these can typically be daisy chained together with no problems as their amplifiers are built in.

Below are some mentionable high-grade audio cables typically used for guitars and PA systems:
IO Audio Technologies

Speakers operate with an AC voltage signal, and get damaged by DC voltage, otherwise known as clipping. Higher amplifier to speaker wattage is preferred, this keeps your amplifier running cooler, free from being over-worked, and free from under power clipping. An AC signal is a smooth alternating wave, and the wave will become flat towards the peaks of the waves when clipping occurs.

Testing your actual setup for clipping can be done by using an oscilloscope found here. High end audio systems may have oscilloscopes built into a car dash or mixer board so the speaker waveform can be constantly monitored at various frequencies, volumes, and tracks, -the visual is also a nice feature. Panel meters like these (voltage, current, power, frequency, temp. etc.) are also nice to have in higher end audio systems to monitor levels.

Below are some mentionable capacitors one might use in a car audio application to keep power delivery constant. Although these are simply wired in parallel to a battery, initially charge these with a series resistor or equal voltage incandescent light bulb, otherwise it will act like a short to your battery:
1182-1027-ND | 283-4464-ND | 1182-1029-ND | 1182-1028-ND

Series/Parallel Voice Coil Formulas:
Parallel: 2 or more current paths (positives to positives, negatives to negatives)
Series: 1 current path (negative to positive)