# Dissimilar sub as an MBM



## Insearchof (Oct 21, 2014)

I'd like some input from the sub gurus on the forum. 
I understand that integrating 2 identical subs in proper locations is difficult enough and this idea will probably be frowned on but...
I currently have an LV12r and Emptek ES1010i. 
The Emptek was moved to another system after I purchased the Rythmik. I'm quite happy with the extension of the LV12r for movies and games but I'm looking for more output for music. My thought was to add the Emptek back in to the mix for music use only. I wouldn't even turn it on unless I'm listening to tunes at higher than normal levels which happens only a couple times a week.
Normally I wouldn't consider this an option and just get a 2nd LV12r but floor space is at a premium and the cost of a 2nd Rythmik won't fly. 
The Emptek has a smaller footprint and I may be able to squeeze it in by the main LP because of this - essentially a nearfield placement.
I'm considering a 30hz or 50hz Fmod on the EMptek to leave everything under to the LV12r. 
Here's a chart from the Audioholics review/test of the Emptek:

Frequency (Hz) SPL (dB)
20 85
25 91
30 97
40 102.5
50 106
60 105
80 105
125 105

The Emptek starts to pick up its steam around 30. 
Matching the levels between the 2 may be difficult but I think it's worth a shot.
The Rythmik sits just to the right of my center and sounds best there. Corner loading in my room makes for some boomy, uneven sound and the 2 channel music imaging suffers.
Anyone have any thoughts or input to help in this endeavor besides getting a bigger more capable single sub?


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## theJman (Mar 3, 2012)

I'm not a big fan of MBM's - and I don't believe too many others are either, so the idea probably won't get much love - but I don't see why it can't be done. If your hearing is sensitive you might pick up the differences, and you can count on it being a little 'interesting' to get everything tuned properly, but I don't see any reason for you not to at least give it a shot.


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## tonyvdb (Sep 5, 2007)

The smaller sub may work well near field. Put it right by the listening position.
But I agree, not really ideal to mix two different subs.


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## willis7469 (Jan 31, 2014)

Just wondering how big is your room? Are phase and crossover in proper alignment? Jman did a nice review on the lv12r that makes me feel like something might be off. Especially, as it seems to satisfy your output needs for movies. If phase is off, you could have created a null for example. Or placement might have created one in a certain range that makes it feel pulled back for your music style. Or your room is too huge! Lol


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## Insearchof (Oct 21, 2014)

willis7469 said:


> Just wondering how big is your room? Are phase and crossover in proper alignment? Jman did a nice review on the lv12r that makes me feel like something might be off. Especially, as it seems to satisfy your output needs for movies. If phase is off, you could have created a null for example. Or placement might have created one in a certain range that makes it feel pulled back for your music style. Or your room is too huge! Lol


The room is a little large (3800 cu ft) for a single LV12r. The crossover is set to 60hz in the receiver. According to the LV12r quick guide, the phase control has no function when using the LFE in on the sub amp.
I have been trying to work on this: http://www.rythmikaudio.com/phase3.html to determine the required delay. I'm terrible with math.


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## tonyvdb (Sep 5, 2007)

what receiver are you using? if it has auto room EQ it will do a good job of setting the delay.


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## Insearchof (Oct 21, 2014)

Update and a few thoughts:
I placed the Emptek about 4 feet from the main LP and started trying various music last night to get the levels and phase dialed in.
At the main LP there was an instant improvement in punch and presence to all music even at easy listening levels.
I started out hot on the Emptek's gain and continued to trim it back to find a suitable balance with the LV12r. I adjusted the phase to get rid of some boom as well.
I even dialed the LV12r down a little bit.
There is a distinct sonic difference between the 2 and it will take a lot more tweaking to get it just right but I think after several hours of listening last night I made good headway. 
I'm not too concerned with other seats in the room but the sound now seems to have even more balance just about everywhere you go which is a nice unexpected perk.


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## Insearchof (Oct 21, 2014)

tonyvdb said:


> what receiver are you using? if it has auto room EQ it will do a good job of setting the delay.


I have a Yamaha RX-A700 with YPAO. I'm not thrilled with the results that I get with YPAO. In this room or any other I've used it in.


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## tonyvdb (Sep 5, 2007)

Ok, Ive also heard people say they dont like YAPO and what it does not do for the subs.


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## Andre (Feb 15, 2010)

I would probably try to link your smaller sub to your mains stick it right beside or behind them and run them as large. Run the larger sub though the sub out as usual.

Might sound awesome or it might sound terrible.:dontknow: Its an experiment...:nerd:


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## Insearchof (Oct 21, 2014)

Andre said:


> I would probably try to link your smaller sub to your mains stick it right beside or behind them and run them as large. Run the larger sub though the sub out as usual.
> 
> Might sound awesome or it might sound terrible.:dontknow: Its an experiment...:nerd:


Here's the room layout.

 

I tried the Emptek to the left of the center speaker with the LV12r on the right. It helped a little but I wasn't impressed with the minor improvement.
One thing that's missing from the layout is the audio tower (holds the receiver, amps, ps3) that's on the left side of the center speaker.
The Emptek is currently in the back right corner of the room between the love seat and couch. 
At this point I'm trying to decide if I should get an Fmod to throw on the Emptek. As it is, it seems to roll off around the mid to high 20's without one which is ok as I'm getting the lower stuff with the LV12r in its current spot.


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## Andre (Feb 15, 2010)

IF you are running them both through the sub out I figure you will always have problems. My idea is to (if the sub has them) run the main out of the AVR to the high level in of the sub then the high level our to your main speakers basically added a woofer to your mains. This way you will get more Bass but only have one Sub Bass driver


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## Insearchof (Oct 21, 2014)

Andre said:


> IF you are running them both through the sub out I figure you will always have problems. My idea is to (if the sub has them) run the main out of the AVR to the high level in of the sub then the high level our to your main speakers basically added a woofer to your mains. This way you will get more Bass but only have one Sub Bass driver


Ah, I think I see what you're point is now. Hmm, Maybe I'll try that too.:scratch:


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## willis7469 (Jan 31, 2014)

Andre said:


> IF you are running them both through the sub out I figure you will always have problems. My idea is to (if the sub has them) run the main out of the AVR to the high level in of the sub then the high level our to your main speakers basically added a woofer to your mains. This way you will get more Bass but only have one Sub Bass driver


 I think this might be worth a try too. I'm normally not fond of high level ins, but this is an edge case that might benefit. Good luck!


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## Insearchof (Oct 21, 2014)

Ok, dumb question time. 

I have the receiver preouts for the L+R mains going to an external amp. The receiver only powers the center. 
Can I just use an RCA splitter to send the signal to the external amp and the sub's line in? Will SQ for the mains suffer due to the splitter?


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## Andre (Feb 15, 2010)

No, doing that would send a full range signal to the sub which would sound horrid. Speaker wire out of the amp the the high level input on the back of the sub, high level out to the mains. You will have to play with the crossover adjustments on the back of the sub to blend the two nicely


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## Insearchof (Oct 21, 2014)

Andre said:


> No, doing that would send a full range signal to the sub which would sound horrid. Speaker wire out of the amp the the high level input on the back of the sub, high level out to the mains. You will have to play with the crossover adjustments on the back of the sub to blend the two nicely


Ah, ok. That's not an option on this sub. 
Wouldn't the sub's crossover still function with the line in though?
More testing is in order.


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## Andre (Feb 15, 2010)

might.....I don't know, something to test


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