Proper subwoofer distance setting

[davef]

Rythmik has just published a useful app to help calculate the proper subwoofer distance setting for your receiver. This will optimize phase, which is critical for achieving the best blend between your speakers and subwoofer.

http://www.rythmikaudio.com/subtuner.html

Note: You must have Java installed.

[Mag_Neato]

Looking at the spreadsheet, I see the closest woofer size to match the Sierra-1 is 5.25", where the Sierra's woofer is 5.5", probably no difference.

I let Audyssey MultEQ do the speaker setup, and I must say the sound is much more coherent and focused, with the bass integrating beautifully.

It set the Sierra-1's as large, Bass on "Mix" with a 60Hz crossover. I reset them as small, 80Hz.

[ride525]

Dave, and all,

There is a new calculator, here is the URL:

http://www.rythmikaudio.com/subtuner2.html

And Ed, Ascend lists the Sierra with a 5.25" woofer, so it should fit the calculator just fine.

Jeff

[kgabest]

Hi Dave and other members, I bought the lv12r sub with front Sierra-1s, I don't see this sub listed in the sub tuner, should I use the result of F12 maybe ?

[Dark Ranger]

Hi Dave and other members, I bought the lv12r sub with front Sierra-1s, I don't see this sub listed in the sub tuner, should I use the result of F12 maybe ?

The FV12 would be a better match to the LV12R.

You might also consider contacting Brian Ding or Enrico Castagnetti at Rythmik for more info.

[kgabest]

Jacob, thanks, it makes sense as lv12r is vented.

[Mag_Neato]

Digging up an old thread here.

I recently changed my 2 channel system configuration from using the AVR's bass management with distance setting, to running the preouts into my sealed 12" Rythmik then back out to a separate amp powering my Sierra-2's and using Pure Direct mode. I set the crossover toggle on the Rythmik plate amp to 80hz/24db Linkwitz-Riley filter setting. I did not touch the phase knob which is currently at "0". The sub sits directly in the center between the L/R Sierras. The distance to listening position(LP) is nearly identical between the sub and mains, the sub may be slightly closer as it is directly in front of the LP.

The sound is great, but if there is a way to dial in the sub using the phase knob than I would like to play with that. Dave/Brian.....any recommendations?

Thanks!

[RythmikAudio]

YOu can go into AVR speaker configuration and adjust subwoofer distance to be up to 3ft further than what it actually is, assuming you use LINE-IN. If you set crossover to 80hz, the full wavelength is about 12ft. Sound speed is 1100ft/sec. So half of that (6ft) is phase inversion. So you can easily do a +3ft to -3 ft scan with 1 ft at a time. You should notice the sound change in the mid bass area. With correct phase adjustment (which we here use distance adjustment to achieve the same goal), you should hear the midbass firms up. The next adjustment is the sub level. You can also do that via AVR menu. Too much midbass will make the kick drums sound like they are in your face, or sound like they are in front of other instruments. But a more natural reproduction is the kick drums should sound like they are from behind other instruments.

[Mag_Neato]

Thanks for the response, Brian!

The way I have it hooked up with the L/R preouts of the AVR feeding into the Rythmik and having the crossover in the Rythmik filtering anything below 80hz to the amp, which then powers the Sierra-2's, and running things in Pure Direct in the Marantz AVR, All digital processing/bass management within the AVR is bypassed. So I guess the phase adjustment is the only way to compensate for distance, correct?

[RythmikAudio]

So I take it that you use our HPF output from F12 and feed your power amp driving Sierra-2. In this case you should not need any phase adjustment. I suggest to try both AVR/12 and 80hz/24 LPF switch position and set the crossover knob to max to see if you can hear difference between the two just by flipping the LPF switch.