PYLE Audio PCM20A - Manual (Page 6)

SYSTEM 3 : Two (or more) Speakers in Parallel
NOTE : Connect the speaker (+) to the amplifier's 8-Ohm terminal, depending on the
TOTAL IMPEDANCE of the two speakers. If each speaker has an impedance
of 16-Ohm, the total speaker impedance in this series configuration is 8 ohms.
SYSTEM 4 : Four Speakers in Series and Parallel
NOTE : Although the description above is for connecting two series pairs of 8 Ohms
speakers in a parallel hook up, you may also select to combine a series pair
and a parallel pair in a parallel hook up, simply be sure you have calculated
the total impedance, and attach the speaker (+) circuit wire to the proper amp
terminal.
SYSTEM 5 : Connecting Speakers with Transformers
NOTE : When the 25V or 70V constant line voltages are used, a line matching
transformer must be used with each speaker, All transformers must be
connected in parallel, never connect line transformers in series.
5 - Pyle Home PCM20A Manual