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REL .LFE input

I just purchased the Technics SU-G700 integrated and it has a left and right pre-out that can be used for a subwoofer - my REL. 

 

I’m currently using the high level connection but thought about trying the LFE connection as a way to reduce a very low level hum I’m getting in the subwoofer. No amount of connecting he system to one power outlet or grounding has solved it, and it only happens once the speakon connection is connected to the subwoofer. 

My only issue with this LFE solution is that there is only one single input on the subwoofer, but the pre-out is in stereo. The question is how much audio low bass information am I losing if I only run one RCA from, say,  the right channel on the integrated to the sub.

BTW, this is a dedicated two channel set up, not used for TV. 

last_lemming
crustycoot
595 posts
 

I don’t know the answer to your Speakon dilemma, but I do believe it is inadvisable to use a Y adapter from stereo pre-out to LFE in, nor would I connect one channel. The correct solution is a buffered summing circuit, but you’re going to have to DIY, if all else fails.

jastralfu's avatar
jastralfu
216 posts
 

Have you tried this:
 

I just got two T/5x subs and got them set up no issues, that doesn’t help you but the rca trick on the webpage above might.

rooze's avatar
rooze
577 posts
 

I had the hum issue on class D monoblocks. I followed RELs procedure for Class D fully differential amp connection and it hummed like crazy. I then connected using both leads (+ and -) and it’s dead quiet. There’s some risk though as REL says not to do that.

I thought the .1 connection had to come specifically from a receiver with.1 output as it bypasses the internal xo in the sub, so you can’t connect from a pre out on a standard preamp to the.1 input. Maybe I misread that part in one of the posts above.

 

last_lemming OP
632 posts
 

Well the wiring checked out to be good. 
 

 

jastralfu's avatar
jastralfu
216 posts
 

Did you try the rca grounding suggestion from REL?  I read that having the sub plugged into the same circuit as the amp can make a difference as well.

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