New Monolith 15 Subwoofer seems underpowered, do I have unrealistic expectations or did I get a lemon?

[movingtarget75]

Just got a new Monolith 15" subwoofer and it seems underpowered compared to my old Outlaw LFM Plus.

Do I have unrealistic expectations or did I get a lemon?

Only had about an hour to tinker around with it but here is what I have done so far:

Plugged it into the receiver using my old presets for the Outlaw and ran the test tone just to see if it would output a signal. Ran through the other channels down to the subwoofer and…nothing, complete silence.

Checked the switches on the back, finally turning the gain up to maximum and got a very faint signal confirming the sub was getting a signal from the receiver.

Set the volume control back to the middle and ran Audyssey to configure the new sub. Audyssey picked up right around 75 DB and gave an approval for the volume setting and I proceeded with the setup.

When I setup the Outlaw a while back Audyssey said it was too powerful and would only continue setup after I turned it down (the Outlaw was also set halfway). I was expecting the same experience with the Monolith, but no, Audyssey was comfortable with the Monolith’s power levels.

After completing setup I ran the test tone again to see what the speaker levels where, the new Monolith was at +/- 0.0 db. Per comparison the Outlaw was set at -4.5 db. Even with the initial tuning the test tone for the Monolith was still inaudible at default volume.

I proceeded to run a demo using some of my favorite demo scenes: Superman fighting the terraformer from Man of Steel, the Balrog in Moria from Fellowship of the Ring, and the King Kong race scene from Ready Player One. I’ve watched each of these scenes multiple times and I am intimately familiar with how they sound and feel.

On the Outlaw each one is powerful, with enveloping sound, and thudding punch on the Monolith they were flat and lifeless, almost as if the entire bass mid-range was missing.

On the Man of Steel scene the terraformer pulses with a powerful, oppressive sound wave before finally exploding when struck by Superman. Playing the scene on the Monolith the omnipresent hum and vibration were completely missing with only a solid thud when the terraformer explodes.

In the Moria scene, as Gandalf detects the presence of the Balrog, you see light from the Balrog’s flames reflecting down a long corridor and you feel a low audible growl as the Balrog approaches. Again, completely missing.

In the Ready Player One race scene there are a lot of atmospheric mid range effects with some massive thuds when King Kong shows up and lands on the race track. The Monolith registers the King Kong thuds but the rest of the race is flat and lifeless.

I know every sub is different and you have to tune them but it seems like the Outlaw has to be reigned in to keep it from getting out of control while the Monolith really has to be pushed to even show up let alone impress.

Monolith has a reputation for quality control issues and I wonder if I have a lemon. This sub is far, far less powerful than what I expected based on the published reviews.

I have personal experience with defective Monoliths, this subwoofer is a replacement for a Monolith I received that was completely dead on arrival and wouldn’t even turn on.

I’ve had the Outlaw for about 8 years and it’s really the only subwoofer I’ve worked with. I read about all the other subs but have little hands on experience with actually getting them setup.

Trying to be fair here and wanted to get more opinions. Am I off-base expecting the Monolith to behave similarly to the Outlaw? Do I need to tweek it more, or is it bad?

 

[shadyJ]

The Outlaw has a much more sensitive gain than the Monolith subs. You were probably running the Outlaw sub hot as well. The Monolith 15" has far more headroom than the Outlaw LFM Plus, especially in deep bass. The THX specification has very strict control over how the gain can be arranged. If I were you, I would crank the LFE output in the receiver by about 6dB. You just need to tweak it to your taste. Don't be afraid to crank the volume dial on the Monolith sub itself too. It can throw a hard punch, it just needs more of a push to be compelled to do so.

 

[lovinthehd]

The Outlaw has a much more sensitive gain than the Monolith subs. You were probably running the Outlaw sub hot as well. The Monolith 15" has far more headroom than the Outlaw LFM Plus, especially in deep bass. The THX specification has very strict control over how the gain can be arranged. If I were you, I would crank the LFE output in the receiver by about 6dB. You just need to tweak it to your taste. Don't be afraid to crank the volume dial on the Monolith sub itself too. It can throw a hard punch, it just needs more of a push to be compelled to do so.

LFE output?

 

[movingtarget75]

Thanks Shady, I’ll keep working with it.

One of the lessons I’ve learned from the Outlaw is to not push it because it goes from sounding great to sounding terrible with just a small adjustment of the dial. Over the years I’ve figured out where that line is: at the receiver the sub is set to -4.5, the LFE at 0, and on the subwoofer, gain is set to 3 (of 9).

It sounds great at those levels but if I turn the subwoofer gain up to 4 or 5 it’s really flirting with disaster. Turning it all the way up would be disaster--I'm pretty certain it would blow out.

It seems like I need to unlearn that lesson with the Monolith and not to be afraid to crank it.

 

[shadyJ]

Thanks Shady, I’ll keep working with it.

One of the lessons I’ve learned from the Outlaw is to not push it because it goes from sounding great to sounding terrible with just a small adjustment of the dial. Over the years I’ve figured out where that line is: at the receiver the sub is set to -4.5, the LFE at 0, and on the subwoofer, gain is set to 3 (of 9).

It sounds great at those levels but if I turn the subwoofer gain up to 4 or 5 it’s really flirting with disaster. Turning it all the way up would be disaster--I'm pretty certain it would blow out.

It seems like I need to unlearn that lesson with the Monolith and not to be afraid to crank it.

The Monolith is heavily protected and can't be over-driven. Run it as loud as you like; it will be OK. The Outlaw sub was using an analog amp with fairly relaxed filters set as limiters, and they could be overdriven if pushed hard enough. One of the only subs I ever really bottomed out in subwoofer testing was an Outlaw LFM-1 EX. They were very good subs for the money but they were not bulletproof.

 

[Pogre]

So how big is your room?

I had a pair of 10" subs in a huge room and upgraded to a pair of 15"s. Pretty much immediately it seemed like the bigger subs weren't putting out as much as the smaller ones. What was happening is the smaller subs were being pushed a lot harder and distorting, which added more noise. The bigger subs were producing just as much bass, more actually, but it was a lot cleaner. I think that lack of distortion and noise translated to perceived less output. I just wasn't used to clean effortless bass.

 

[movingtarget75]

My room is about 11 x 17.

The Outlaw sub I’m upgrading from is a good sounding sub but it’s easy to push it too far.

Based on my experience with the Outlaw I was hesitant about turning up the Monolith since old habits are hard to break. My hesitation was unfounded, the Monolith is definitely more robust.

I’m still working on blending it with my other speakers but after some initial trepidation I’m pleased with what I’m hearing so far.