CurtPalme.com Home Theater Forum

[BTS]

hi i think it's possible to using 10 ohm resistors (?) to keep impedance correct but am not sure, i want to build some sort of connector that will allow one set of l-r in but have two each l & r out (amp has no a-b speaker selection, 8 ohm connection for one set l-r speakers)

[Curt Palme]

That will work. Not very efficient, but cheap.

the better way is to use an 'impedance matched speaker selector'. That usually uses a more efficient transformer in it to match the receiver/amp to the number of speakers you have. The deluxe ones also have individual volume controls per speaker pair.

Check eBay. Niles, QED are decent ones, but there are piled of OK knockoff ones as well.

[Curt Palme]

That will work. Not very efficient, but cheap.

the better way is to use an 'impedance matched speaker selector'. That usually uses a more efficient transformer in it to match the receiver/amp to the number of speakers you have. The deluxe ones also have individual volume controls per speaker pair.

Check eBay. Niles, QED are decent ones, but there are piled of OK knockoff ones as well.

[BTS]

thanks curt, i like cheap, have an old console stereo in garage that has "internal/external" speaker selector switch, want to run wires into yard from external connection-->volume control-->one pair speakers--> speaker level "in" to 8"powered subwoofer. then able to set volume at console & use secondary system in yard (if i change value of resistors can i run "three pairs" in yard, two left, two right & sub-?)

[Curt Palme]

Ohms law dictates that 1/Rtotal = 1/R1 + 1/R2 + 1/R3, etc

The '/' sign is 'divide by'.

You want Rtotal to be no less than 8 ohms. The formula above will give you the series dropping resistors you need to maintain an 8 ohm load on the receiver.





And you bastages didn't think I knew math.

[Curt Palme]

Ohms law dictates that 1/Rtotal = 1/R1 + 1/R2 + 1/R3, etc

The '/' sign is 'divide by'.

You want Rtotal to be no less than 8 ohms. The formula above will give you the series dropping resistors you need to maintain an 8 ohm load on the receiver.





And you bastages didn't think I knew math.

[AnalogRocks]

Why not wire in series?

[AnalogRocks]

Why not wire in series?

[Curt Palme]

He could do that, but as the overall impedance goes up, the total wattage goes down. Also, then you can't put on/off switches in line with the resistors to turn off certain areas. THe outdoor speakers will almost always need more volume than speakers inside.

BTS, you'll probably want a volume control for the inside speakers as well, so at that point get one of the volume control boxes.

Here, you can't build it for this price:

http://cgi.ebay.com/NILES-Speaker-Switcher-Volume-Control-/220723392311?pt=LH_DefaultDomain_0&hash=item336423af37

[Curt Palme]

He could do that, but as the overall impedance goes up, the total wattage goes down. Also, then you can't put on/off switches in line with the resistors to turn off certain areas. THe outdoor speakers will almost always need more volume than speakers inside.

BTS, you'll probably want a volume control for the inside speakers as well, so at that point get one of the volume control boxes.

Here, you can't build it for this price:

http://cgi.ebay.com/NILES-Speaker-Switcher-Volume-Control-/220723392311?pt=LH_DefaultDomain_0&hash=item336423af37