TOA Canada - Series Parallel Combination
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Dear Dr. Sound, 

Regarding the BG-2120 Mixer Amplifier.  There is a 4ohm speaker level output which I need to go into an existing 6 speaker setup.  Each of the 6 speakers have a nominal impedance of 8ohms.

Can you guide me on how this can be wired to function with the BG-2120. Would you be able to supply a wiring sketch if possible.


Dear Sergio,

To have your speaker load not dip below 4 ohms you will need to do a series parallel combination.  Essentially wire 3 pairs of speaker in series that are paralleled to the speaker output.

This would give you a 5.33 ohm load.  

Here's the math behind it:

Two 8 ohm speakers in series equals a 16 ohm load (in series the impedance is added together)

With three 16 ohm loads in parallel you divide the # of runs (3) by the impedance of each load (16 ohms)

16 (impedance of each run)/3 (# of runs) = 5.33 ohms

SO-MIX Instructions

Your Dr. Sound

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