Dual Monolith 15" Ultra's

[408Revo]

I decided to upgrade my dual 12" monolith subs and got dual 15" subs, I got to say that it's a night and day difference. Can't compare the sound dual 15"s give over the 12"s. Unfortunately it did not work for MLP. Almost everywhere else the sound was amazing. Through out the entire house I had bass but not where I sit down. I basically tore my entire room apart moving everything around trying to get these 15" to work with my room but was unsuccessful. I tried placing the 15" in every location possible in my room but my MLP was lacking sound. I'm trying to understand why this happened if my dual 12"s sounded great at my MLP. Also, I placed the 15"s woofer at the same location as the 12"s but did not work for me. Did I do something wrong or can this happen?

 

[Sonnie Parker]

Typically you get fairly close to the same response if the front of the sub is at the same location. You may get more extension in both directions with a more capable sub, but otherwise I don't think it would be that much off, unless they are ported and tuned to a different frequency.

Have you reconnected the 12" sub in one location to see if it measures as it used to measure?

 

[408Revo]

Yes, I just reconnected the 12”s instead for now and put my living room back together. A little bummed out that I couldn’t get the 15”s to work for my MLP. I know that my room is not ideal as it opens up to the kitchen and opens up to two other hallways. Going to keep doing research and see what I’m doing wrong or the reason why this is happening. I might just get a third 12” and call it good.

 

[Sonnie Parker]

That is quite odd for sure, and a third sub could be a good option for you... or just see what adding the 15 might do for you. It may interact well with the 12" subs.

 

[408Revo]

I agree.
I went at it again today. Tried different variations and no luck. My (2) 12s sound better at my MLP over the (2) 15s. Sending them back and ordering another 12. Hopefully with the third, I’ll get a flatter curve.

 

[Gerry Iaria]

I agree.
I went at it again today. Tried different variations and no luck. My (2) 12s sound better at my MLP over the (2) 15s. Sending them back and ordering another 12. Hopefully with the third, I’ll get a flatter curve.

That's very strange, you would think that with the 15's you'd get better, did you try one of the 15 as a 3rd sub, to see if it works before buying anoter 12??

 

[deercreekaudio]

I decided to upgrade my dual 12" monolith subs and got dual 15" subs, I got to say that it's a night and day difference. Can't compare the sound dual 15"s give over the 12"s. Unfortunately it did not work for MLP. Almost everywhere else the sound was amazing. Through out the entire house I had bass but not where I sit down. I basically tore my entire room apart moving everything around trying to get these 15" to work with my room but was unsuccessful. I tried placing the 15" in every location possible in my room but my MLP was lacking sound. I'm trying to understand why this happened if my dual 12"s sounded great at my MLP. Also, I placed the 15"s woofer at the same location as the 12"s but did not work for me. Did I do something wrong or can this happen?

This could be an issue of: inversion, incorrect crossover points or delay issues that are causing your subwoofers not to integrate with the rest of your system.

In our tech blog we explore how to reach the goals of proper subwoofer integration:

Goals:

• Optimization of level, crossover and delay settings
• Seamless integration of the last audio spectrum octave
• Elimination of excessive driver excursion and heat dissipation in full-range speakers
• Maximizing clarity and impact

Room EQ Wizard (REW) is used as a tool during the miniDSP Device Console setup. Hopefully some of these methods will help you discover a remedy for your situation.