Two speakers on a LokSound v5 decoder.

[Trnsrus]

I'm planning to use two 8 ohm 11mm x 15 mm sugar cube speakers with a LS 58741 decoder. What are the performance differences between a 4 ohm parallel and a 16 ohm series speaker connection. Afaik, the decoder is rated for a 4 to 32 ohm speaker load.

[peteski]

The decoder audio amplifier runs on a fixed voltage.  It is all about the wattage.  4 ohm config will result in more power supplied by the amplifier than if it was driving an 8 ohm speaker, and 16 ohms will result in less power supplied by the amp. to the speaker than into 8 ohm load.  That is because with fix voltage the resistance/impedance is what will limit the maximum current.  Lower resistance/impedance = more current. More current at certain voltage = more power.  More power = louder sound.  Of course the speakers have to be in enclosures to achieve the volume and sound quality.

But also remember that in multi-speaker setups the speaker polarity (phase) matters.  With parallel connection connect all positives together and all negatives together.  In series connection connect positive side of one speaker to negative side of the the next speaker (daisy chain).

[jdcolombo]

As Peteski explains, wiring the speakers in parallel, resulting in a 4-ohm load, should result in theoretically louder maximum volume.  But it is also more taxing on the audio amplifier circuit.  If wiring in series for a 16-ohm load gives sufficient volume, I'd opt for that since it puts less stress on the audio amplifier.

And be sure to follow Peteski's wiring advice.  Critical for proper operation.

John C.

[Trnsrus]

Questions answered; thanks for the replies, Peteski and John C.