One exception to this idea is the current version LokSound
decoders (or others) that actually like 4-ohm loads, so wire the
two 8-ohm speakers in parallel, as shown in (8). That’s why I
suggested you find out what your decoder likes and what it will
tolerate before you start.
Three speakers
Three 4-ohm speakers in series, as in (9), will yield 12 ohms
which will work just fine with almost all decoders designed for
8 ohms. I did this in a brass HO-scale Overland narrow hood
diesel and the results were amazing.
Four speakers
The four speakers shown in (4) were wired in a series-parallel
fashion. That is, two sets of two speakers are wired in series, as
shown in (7). Each series group has twice the impedance as the
original speakers. Then these groups are wired in parallel, mak-
ing the final impedance exactly what the speakers started with.
DCC Impulses Column - 7
9: Three speakers wired in series – the final impedance will
be three times the speaker rating – 4-ohm speakers yield a
12-ohm load.
9
MRH-Jan 2014
