2. amps-preamps
  3. 151159-126

REL subs with Rowland Amplifiers

I'm having issues connecting my REL Carbon limited subwoofer to my Jeff Rowland 625 S2 amplifier via the high-level input. I connected my sub according to REL's instructions...yellow lead to positive on one channel, red lead to positive on the other channel, and floating the black wire(ground). I get minimum output when connected according to the instructions. When I use the low level input, the output is sufficient and the sub sounds great. Per my conversation with Jeff Rowland I need to ground the black wire by loosening a screw on the amplifier and connecting the black wire, but if it isn't properly grounded I may damage my amplifier. Is there anyone that owns a REL with Jeff Rowland 625 S2 amplifier or other balanced differential amplifier? If so, how do you connect your REL via the high-level input. Is there an easier way to ground the wire than unscrewing the screw on my amplifier. I just don't want to unscrew the screw and prefer another method of grounding the sub.   
ricred1
almarg's avatar
Ag insider logo xs@2x
almarg
9,670 posts
 
Regarding line-level vs. speaker-level, in the specific case of speaker-level connections to Richard’s amp it seems to me to be possible that the less than ideal nature of the ground path/signal return path between the subs and the amp (with the AC safety ground wiring being part of that path, as I had explained earlier) might be a factor contributing to his findings.

Generally speaking I would not expect comparisons of line-level vs. speaker-level involving amps whose outputs are not balanced or bridged to necessarily have much correlation with comparisons involving amps whose outputs are balanced or bridged.

Also, as I had mentioned earlier in the thread it would seem logical that the more transparent and accurate the sonics of the amplifier are, the less likely REL’s rationale for speaker-level connection is to be applicable.

Best regards,
-- Al

daveyf's avatar
daveyf
2,871 posts
 
Al, surely the more accurate the amp is, the more accurately it will pass on the signal...therefore what REL is basically stating is correct. Either way, I totally get the point that the subs see exactly the same signal as the mains in REL’s high level set up.
almarg's avatar
Ag insider logo xs@2x
almarg
9,670 posts
 
... surely the more accurate the amp is, the more accurately it will pass on the signal...therefore what REL is basically stating is correct.
Hi Davey,

My point in that regard was that the more accurate the amp is the more similar the sonics of its outputs will be to the sonics of the outputs of the preamp. Which seems to me to mean, everything else being equal, that there will tend to be less difference between speaker-level vs. line-level connections than there would be if the amp is less accurate, and therefore alters the signals to a greater extent.

Best regards,
-- Al


ricred1 OP
2,021 posts
 
No matter what REL claims I submit that the end user owes it to themselves to try both inputs. All systems are different and you never know what sounds best unless you try both inputs. I still prefer my REL Carbon Limited to the JL Audio F112 v2 for 2-channel. I consider adding the RELs to be one the best Audio decisions I've ever made. 
jtcf's avatar
jtcf
1,618 posts
 
FWIW  I prefer the line level connection with my subs too.It's easier to blend them in and is more articulate, to my ears anyway.
More to discover