Reciever to subwoofer compatibility

CBJ023

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Mar 17, 2013
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Hello all, so I've recently been getting into audio and try ing to understand it all. I have a JBL DCR600ii that I want to try and pair with a Song SS-WSB111 sub. The receiver has two subwoofer outputs, one is LFE, the other is a 8ohm positive negative terminal. The sub is 6ohm and does not have an amplifier (as in it receivers its power directly from the receiver) Would I be able to connect it to the JBL receiver through the positive/negative terminal?
 
Solution

It will have 4 separate amplifier blocks in it (two stereo blocks for front and rears and two singles for the centre and sub channels), so running two speakers makes no difference in so far as the stress on the individual amplifiers is concerned (i.e. it...

nitrium

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Jul 27, 2009
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I'd say not a great idea. You generally shouldn't connect 6 ohm speakers to an 8 ohm only amp as it might damage the amp over the long term (while it will "work" in that it will produce quality sound as expected, the amp will run somewhat hotter than it normally would since speakers with a lower impedance will draw more current and thus generate more heat than speakers with a higher impedance). Good quality amps will handle it fine though and will clearly state they have 4-16 ohm speaker compatibility in the amp specifications (so check that before abandoning the idea).
 

CBJ023

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Thanks for the feedback! I only have it running two speakers right now it can support 5.1 do you think it would be ok because its not powering as many speakers so the extra heat would just be what it normally uses? Or could I put a 2ohm resistor in series with the sub? And can the receiver power the sub? I read about the receiver having to have a built in amp if the sub didn't have its own power source but I'm not sure if my receiver has a built in amp. Thanks again for the help.
 

nitrium

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It will have 4 separate amplifier blocks in it (two stereo blocks for front and rears and two singles for the centre and sub channels), so running two speakers makes no difference in so far as the stress on the individual amplifiers is concerned (i.e. it doesn't work by sharing a single big amplifier block). I have heard of people putting a resistor on the speaker to turn it into an 8 ohm, but not something I have any experience with. As for your receiver powering an unpowered sub woofer, again I'm not really sure - how many watts is the speaker rated for and how many watts can the amp deliver? Both will be stated on the specifications. Assuming you don't run it super loud, and monitor/control the extra heat you should be alright to connect 8 ohm amp to 6 ohm speaker but again, it's not something I'd recommend myself if you value your gear. Personally I'd get a separate 6 ohm amplifier for the sub woofer that is designed for the job.

EDIT: Here is the manual for your receiver (spec page): https://www.manualslib.com/manual/79414/Jbl-Dcr600-Ii.html?page=70#manual
So it will deliver 100W max to the sub woofer which is also likely ~100 W (although I can't find the exact spec). However it's going to get there by demanding more current from the amplifier (more than it's rated to deliver).
 
Solution
It's probably OK to use a 6 ohm load there. Most likely if there are a problem the receiver would just go into protection.
You could wire a 2 ohm non inductive resistor in series with the plus speaker wire
https://www.walmart.com/ip/5Pcs-2-Ohm-25Watt-Aluminium-Clad-Wire-Wound-Power-Resistors-Green/147687580?wmlspartner=wlpa&selectedSellerId=571&adid=22222222227000000000&wl0=&wl1=g&wl2=c&wl3=42423897272&wl4=pla-51320962143&wl5=9004455&wl6=&wl7=&wl8=&wl9=pla&wl10=111838760&wl11=online&wl12=147687580&wl13=&veh=sem
to raise the impedance to 8 ohms.
 

CBJ023

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Ok, I'll test it out and if it works I'll order a 2 ohm resistor off of ebay (Can get 100 for $1 :) ) So my last question is will the sub work if I'm not using 5.1? The way the speakers are connected is HDMI->Monitor->MP3 cable->Receiver will this utilize the sub?
 

nitrium

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Make sure you get a good quality resistor that can handle the current (at least 25 W). And yes, the sub will work 100% fine without the other channels connected (as I stated earlier, all the channels are fully separated and work independent of one another). The receiver will have a low-pass filter (20 -80 Hz) to ensure only the lowest bass frequencies are passed onto the sub. https://www.manualslib.com/manual/79414/Jbl-Dcr600-Ii.html?page=69#manual