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Chameleon2
10-28-2008, 05:57 PM
Using speaker wire only...

What is the best way to connect 2 passive subwoofers?

(1) receiver (L & R) to sub1 then in series to sub2
(2) receiver (L & R) to both subs individually
(3) receiver (L) to sub1 and receiver (R) to sub2

other suggestions welcomed.

GV#27
10-28-2008, 10:12 PM
Are the subs both the same and do they have passive crossovers(big coils,and caps)?

There are a number of issues using passive subs and driving them from the same channels as the main speakers.One being the inability to adjust their levels in relation to the mains/satelites so proper balance will be hard to achieve unless the sub/sats are designed to work together.

Chameleon2
10-28-2008, 10:24 PM
Subs are both RM1000W's

Terminals are + and - for right and left (a total of four terminals).

The original satellites were RM3000's which died. Replaced the drivers which worked one time, then died again; no warrantee.

I just purchased a pair of RTiA1's to replace them. A mild upgrade :rolleyes:.

My receiver, a Denon AVR1500, has L&R fronts (mains), rears and center speaker terminals. The surround is Dolby Pro Logic.

GV#27
10-28-2008, 11:12 PM
Ok then looks like the woofers have no crossover so they will be operating full range and in parallel with the mains.Honestly this is not a good configuration if sound quality is the goal.The woofers will sound dreadful if the upper end of their response isn't filtered,so they really need to be crossed over preferably with an adjustable active type and they should be driven by a separate amp.As well the Denon might not like the load presented to by the parelling of the sub and RTiA1's.

Does the Denon have a sub out connection?If so then you could connect this to another amp and have it drive the subs.
Alternatively you can get an inexpensive plate amp with built in crossover to drive your subs.

Chameleon2
10-29-2008, 06:45 AM
specs for the sub are here (1/2 way down):

http://www.polkaudio.com/forums/showthread.php?t=1161&highlight=rm3000

From the link: The RM1000 was made available as a separate unit for owners who preferred two bass modules, from 1990 until 1995 and had a suggested retail price of $390.00 each. The RM1000 used two 6.5" drivers and a 10" passive radiator, power handling was 125 Watts/channel, with a frequency response of -3dB from 42 Hz to 200 Hz.

Chameleon2
10-29-2008, 06:57 AM
some more info: http://www.polkaudio.com/forums/showthread.php?t=72003

GV#27
10-29-2008, 07:47 AM
Oh Ok I see now, it's a 2 channel sub and you have 2 of them.The spec sheet you linked to indicates it will have an integral passive crossover at 100hz.I'm off to work but will discuss hookup options later.

GV#27
10-29-2008, 08:23 PM
The data sheet says Polk have a recommended way to hook these up if you are running 2 of them.I'm guessing that they recommend connecting the 2 drivers in each cabinet in series.In this way they will present an easy 16 ohm load to the amp.(The total load the amp will see will be less because the RTA 1's will be connected in parallel with the subs).


To hook the sub's drivers in series take a short piece of speaker wire and connect it to the neg terminal on one of the terminal plates,then connect the other end to the pos+ on the second terminal plate.Do this on both subs.

Then from one channel of the reciever connect the pos+ to the unoccupied pos+ terminal on the sub. Then connect the neg - from the same channel of the reciever to the unoccupied neg- on the sub.Do the same for the other channel.


Hopefully thats clear enough and helpful.:)

Chameleon2
10-29-2008, 09:34 PM
Thanks for looking into this; unfortunately, there is no easy way of gaining access to the internals; they are basically sealed units.

GV#27
10-29-2008, 10:16 PM
No need to get into the internals,the pic shows the terminal plate I was refering to.
With a piece of speaker wire simply join the black connector on the top row to the red connector on the bottom row.Then connect the pos+ of the right channel of the reciever the red connector in the top row and the neg - from the recievers right channel to the black one in the bottom row.Do the same for the other sub but connect it to the left channel.