Resistors in speaker circuit to change from 8ohm to 100ohm?

[boxbrownie]

It may be obvious or it may not work at all but I have an old Loksound 3.5 which needs the 100 ohm type speaker, but I have a lot of the newer 4, 6, 8 ohm type speakers, now I was wondering if I can just put a resistor on one of the speaker wires (or one on each wire) to change the impedance......or does it not work as simply as that?

[Pandora]

You could place a resistor  value R  in the output circuit so that  (ohms of speaker + R ) == 100, but the practicality is the sound output would be very low in volume,  90% of the output power would be used by ( or dissipated) i n the resistor and only about 10% of the power would be left over to do the "job-of-work"   ie   make the desired steam / diesel / electric locomotive sound

Edited May 26, 2020 by Pandora

[boxbrownie]

17 minutes ago, Pandora said:

You could place a resistor  value R  in the output circuit so that  (ohms of speaker + R ) == 100, but the practicality is the sound output would be very low in volume,  90% of the output power would be used by ( or dissipated) i n the resistor and only about 10% of the power would be left over to do the "job-of-work"   ie   make the desired steam / diesel / electric locomotive sound

Aha now you have explained that of course, it makes perfect sense........oh well, dig out an old 100ohm speaker then.

[Pete the Elaner]

16 minutes ago, Richard Croft said:

What would happen if you put a 100 ohm speaker in series with an 8 or 4 ohm speaker? I've wondered for a while if it could work, would work, Could you keep the original 100 ohm speaker but then use a better quality more modern speaker to improve the sound?

 

Richard

 

It would be very quiet. I doubt you would be able to hear the 4/8ohm speaker.

[boxbrownie]

2 hours ago, Richard Croft said:

What would happen if you put a 100 ohm speaker in series with an 8 or 4 ohm speaker? I've wondered for a while if it would work, Could you keep the original 100 ohm speaker but then use a better quality more modern speaker to improve the sound?

 

Richard

That was exactly was my thoughts originally, but as Pandora explained it the resistor would be taking the majority of the “action” and the speaker hardly any.
 

Its all this electrickery, it really is! 

[Free At Last]

1 hour ago, boxbrownie said:

Its all this electrickery, it really is! 

Mayhap brother, mayhap.

[boxbrownie]

1 hour ago, Free At Last said:

Mayhap brother, mayhap.

Lookee like me nayboor