I just picked up these components and am installing for the first time. I’m using them to power Polk sda srs loudspeakers and dual JL fathom F113 subs. I have the preamp going to the amps with xlr cables and I wanted to go from the preamp rca out directly into each sub and then have the subs crossover/filter the signals. I did that but the sub output is pretty reduced. So, I guess I need to get a line converter and take the post amp signal from the speaker outs of the m700 , convert that to rca and go into the subs. I just want to confirm that and ask why the preamp into the sub signal is reduced? Is that normal or a problem?
The real Paul has mentioned that the RCA outputs are 6db less than the XLR outputs. So the volume level should be lower, but not a crazy amount lower. Yes this is normal.
What kind of preamp are u using? Do JLs have a high level input?
Thank you
I’m using the stellar dac/preamp. The JLfathom do not have high level inputs
I think I have a better sense of how to ask my question, I reframed it:
I need some help with understanding options for hooking up subwoofers to my Stellar GainCell preamp/Dac. I currently have the gaincell as a preamp to go to a set of M700 mono blocks. I am using the preamp balanced XLR connections to go from the preamp output to the M700 input. Regarding hooking up a set of subwoofers…
- Is it okay to use the low level RCA outputs on the gaincell to feed the subwoofer signal at the same time using the XLR outputs for the loudspeakers?
- If it is okay, what is the difference between the output signal/strength of using the RCA outputs directly into the subwoofers, vs. pulling the signal from the M700 amp output, speaker level and then using a SVS speaker level to low level output adapters?
- Which method do you recommend and why?
Thank you very much. The PS audio set is very impressive in general, but I’m struggling to get the output I’m used to with the set of JL audio Fathom F113 series subwoofers in comparison to an amp set up that has dedicated subwoofer outputs.
The easiest method is number 1 as it avoids the issue with the negative speaker terminals on Class D amplifiers not being a true ground so method number two would involve a lot of un-necessary wiring connections to a ground source. In theory the difference between the RCA and XLR outputs would be 6db but that is easily compensated for with the volume control on the Fathoms.
Thank you, and you believe it’s okay/safe to run both outputs from the gaincell at the same time, XLR and low level?
No problem just the gain difference with line level outputs.
I just thought of another idea. In short, what if instead of using the rca outs for the sub signal and then having a 6db difference, how about I get an xlr balanced y cable and use another set of xlr cables into my subs since they have that input? That way I can can a matched signal going from the preamp to the amps and preamp to the subs?
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The other method is better (using xlr & rca).
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Thank you but can you help me to understand why you say that?
Potential effect on the mid and upper frequencies can be noticeable the more one messes with the mid and upper frequencies by splitting the signal.
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thank you.
Two updates to report. First, I went back to hooking up the subs via RCA low input from the preamp at the same time as using the XLR to the loud speakers. It did improve the integration of the subs “better” than by pulling the high level speaker signal from the amp itself, into a converter/adapter, then into RCA inputs in the sub. Second, I got XLR splitter and switched from the RCA outs to the sub, by now going XLR out of the preamp to splitter, one directly into the M700 amps and the other XLR into each sub. It did the trick in terms of better output and presence. I only have an hour or so of play on it so far, I’ll report back when the cables burn in more and after I can listen to more music.
Thanks for the help and I hope it helps someone else.