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A little confused on how to properly integrate my sub

Hi everyone! Im relatively young and inexperienced when it comes to the more complicated electronics side of audio. Right now for my computer desktop Im using a a pair of LS50s connected to a Musical Fidelity M3si integrated amplifier. I also have an REL T9i connected to the finding posts of the amp and use the High level input like REL dictates.

Ive decided that I really want to properly crossover my speakers and let the sub handle ONLY the low end. I decided to put my Musical Fidelity up for sale and have ordered an Outlaw RR2160 that has integrated bass management. I plan on using a standard unbalanced RCA cable from the Outlaw to the REL. The problem is REL makes this very difficult. Unlike another sub I have where there is a switch that lets you use a filter in the sub or amp, the REL provides no such option. They demand you use play your speakers full range. The knobs on the back of the sub are LO/HI Level (volume I think), Crossover (30hz to 120hz), and .1LFE level (im not plugging into that input anyway).

I assume what I need to do is set the crossover frequency on my Outlaw to 80hz (where I want it), and then plug the Outlaw into the REL through the low level input, then crank the crossover on the sub to 120hz. The sub should only be receiving the low frequencies anyway so by cranking the subs crossover up all the way I shouldn’t be attenuating any frequencies. Does this sound right to you guys? THANKS!
EDIT: After thinking about it, is there any reason not to use the LFE input and bypass the subs filtering? As I understand it, all LFE content is 120hz or below so the sub designers took that into account.
collingraff

Showing 3 responses by martykl

martykl
3,578 posts
 
You have a philosophical choice here:

The "audiophile" way is to play the Kef full range and integrate the Rel as Rel suggests. This is hands-off and maintains the simplest signal path.

The "rationalist" view is to actively cross. This will dramatically reduce distortion. The LS50 (like all speakers using smallish mid bass cones to cover LF) will show dramatically increasing distortion as frequency drops and spl increases. That’s physics. Actively relieving the Kef driver of duty below 100 hz will clean up low end distortion very effectively.

The question is whether it matters. Some say that the ear is insensitive to THD at low frequencies. You have to decide.

BTW - If you do decide to actively cross the system, I’d seriously think about an amp with a digital x-over and room EQ (per the earlier suggestion). It appears that you use exclusively digital source material and IMO crossing in the digital domain is the way to go. IME room correction is the single biggest improvement I’ve ever made to a high end set-up, but you can always defeat it if you prefer that route. (You won’t)
martykl
3,578 posts
 
If you’re concerned about the amp section of an AVR, go for a modest Pre-pro and a stereo power amp of your choice/budget.

IIRC, NAD makes a higher end integrated with these features that’s pretty costly. DEQX and Lyngdorf make excellent products, but they’re even more expensive   The Elac recommendation above is probably the most cost effective solution that I’ve seen.
martykl
3,578 posts
 
I hadn't ever considered it, but Lewinski's idea strikes me as potentially very cost effective.  If I understand the proposal correctly, you'd only need to add the DAC and a multi channel power amp of your choice.  

However, the one caveat here is volume attenuation.  If it's done in the digital domain, you may find that there's an audible impact on SQ (particularly at lower listening levels).  As with all things audio, this is personal and you might also find that it has no impact on SQ.

If attenuation is controlled by the software, then you're effecting it in the digital domain.   If volume control is at the DAC, it could be in either (depending on the design of the DAC) the digital or analog section, but you'd hope it would be analog - in any event you can check the user's manual to find out.

I've never tried it, so I'm not taking a position one way or the other, just pointing out that - if the volume control is in the software - this is the "rationalist's" trade-off in this otherwise very rational solution.
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