Information I have gained about the RSL Speedwoofer 10s MKII that I believe other people could use.
The Question-
"Using the LFE input (coax rca into lfe input only), can I use movie mode AND music mode without switching to 2 rcas in and having to use the crossover controls? If I can, how?
my plan is to hook the sub via coax using the lfe input to a minidsp flex, which will handle the phase, crossover, and volume, and generally mixing those is a bad idea, therefor I want the sub to act the most like a power amp with speakers as possible, but I want to switch between the movie/music modes as I change the music I am listening to- if there is a significant (10% or higher) difference if speed/extension between the 2 dsp modes."
The Answer-
"Hi Rob,
Thank you for writing us. Sorry for the late response.
The low pass control knob has an integrated switch to allow the user to select between LFE and music mode.
Yes, you can use a single RCA input in both LFE and music mode. You will likely notice a difference in output level when doing this because in music mode it is setup to receive signal from both RCA (l&r) inputs and then it is summed internally. If there is only one RCA feeding the stereo inputs in music mode the signal will be lower than if (2) RCA’s were connected which would mean you will have to turn up the level a little more and/or the output from your source. When in LFE mode, the LFE input is adjusted to only receive a single channel LFE output that is pre-filtered (crossed-over) at the source which is most common in audio video receivers.
LFE mode has a specific EQ that is optimized to extend and enhance the bass output with minimal increase in woofer excursion. in this mode the low pass filter is bypassed, relying on the source or other device (such as your minidsp flex) to handle the crossover. If you do this and keep the phase at 0 (full counter-clockwise) there will be no in-line signal “overlap” that might cause a problem for the mini-dsp filtering.
if you wish to use the “original 10s” response (music mode-non LFE enabled), i would suggest turning the low pass knob all the way clockwise (~200hz). This will switch out of LFE mode and will allow any eq/phase/filter adjustments to be processed by the minidsp at least an octave below or more, to minimize any issues related to cascading filter overlap. In your particular situation, (edited)
i would suggest that you do not adjust the phase control on the 10smkii (keep it a zero) and let your mini-dsp managed this. Again, we always recommend experimentation for each customer to tailor to their liking. Please feel free to contact us with any questions."
TL:DR-
AFAIK, you can use 1 rca in with the speedwoofer for LFE and MUSIC MODE (plugged into the LFE input), with the only issue being the signal gain will be lowered internally at the subwoofer amp, and you will have to twist the crossover knob from LFE to MUSIC MODE (200hz) and back when you want to use one over the other. As long as you keep the other amp settings at their default, everything should work well with external dsp. You can use a minidsp for the dsp, and use 2 profiles in the minidsp to account for volume matching with music mode and for not using the other dsp controls on the subwoofer.