# How to enable bass boost/crossover defeat?



## TJEli (Nov 10, 2008)

Hey guys,

I am thinking about picking up one of the package deals from MLS for my office. I would be running the 525Ms without a sub so I would want to defeat the 100hz high pass. Just wondering how this is done? I do not see a switch or anything on the amp itself.

Thanks guys!,

-Eli


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## imported_m-fine (Mar 15, 2008)

You just hit the bass + button. They set the tone control to match the crossover so they cancel each other out.


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## VincentH (May 27, 2008)

Maybe I am still not quite get it. If I push bass + button, what I get is more bass above 100 Hz, is it right Craig?


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## craigsub (Sep 9, 2006)

VincentH said:


> Maybe I am still not quite get it. If I push bass + button, what I get is more bass above 100 Hz, is it right Craig?


No - The bass shelving curve will yield up to +2 dB at 100 Hz and flat to 50 Hz. This works well with most speakers - even small towers. This is even with the crossover engaged (which it always is)

Gizmo is still at its best with a subwoofer, but, as the guys at the Virginia GTG discovered last weekend, it's pretty good without, too. :brainiac:


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## alphaiii (Nov 30, 2007)

craigsub said:


> No - The bass shelving curve will yield up to +2 dB at 100 Hz and flat to 50 Hz. This works well with most speakers - even small towers. This is even with the crossover engaged (which it always is)
> 
> Gizmo is still at its best with a subwoofer, but, as the guys at the Virginia GTG discovered last weekend, it's pretty good without, too. :brainiac:


Resurrecting an old thread to make sure I'm understanding this...

I was running Gizmo with monitors and a sub before, but now that I'm using the ELT towers without a sub, I've been playing with the bass control a little.

So when the bass control is bumped up to max (+14), this brings the bass at 50Hz up, so you'll get a flat response from 50-100Hz now, correct? But, this also results in a 2dB increase at 100Hz? So when looking at the entire frequency range, 50-100Hz is about 2dB higher than the response above 100Hz?

I'm asking because, when the bass is set to max, it seems to me that it is now noticeably overemphasized. I had thought that increasing the bass using the tone control only functions to make the bass linear from 50Hz to 100Hz (the crossover point), but does not increase bass at or above 100Hz. In other words, I thought bumping up the bass would result in a flat response from 50Hz all the way up. 

Judging from the sound, it seems like this method is giving an upper bass bump too. The towers sound overly full in the upper bass/mid-bass, and it seems to muddy up the sound a bit. If I drop the bass a bit, I lose the lower end presence. 

To put it in relation to the music (metal, rock) I'm listening to...setting the bass control to 12 or 14 results in the guitars/bass guitar sounding "thick" and muddy, whereas dropping the bass control down to 8 or 10 cleans things up a bit, but take the presence away from the kick drum (and I love double bass with impact damnit!).

Has anyone else noticed something similar when running Gizmo without a sub and bumping up the bass control?


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## alphaiii (Nov 30, 2007)

alphaiii said:


> Resurrecting an old thread to make sure I'm understanding this...
> 
> I was running Gizmo with monitors and a sub before, but now that I'm using the ELT towers without a sub, I've been playing with the bass control a little.
> 
> ...


bump for input


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## mojave (Dec 30, 2006)

Based on the Gizmo Bass Boost frequency response chart that Craig posted at av123, your listening perceptions are correct. I use mine with a subwoofer, so I don't have your problem (unless my sub is set too hot). I'm not sure what you are using as a source, but with a computer you can either use a slight EQ cut with the soundcard drivers or the media playback software.


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## alphaiii (Nov 30, 2007)

mojave said:


> Based on the Gizmo Bass Boost frequency response chart that Craig posted at av123, your listening perceptions are correct. I use mine with a subwoofer, so I don't have your problem (unless my sub is set too hot). I'm not sure what you are using as a source, but with a computer you can either use a slight EQ cut with the soundcard drivers or the media playback software.


Thanks...I had never seen that FR chart before.

I'm using my PC as a source, so I can try messing with the EQ at 100Hz. Thanks for the help.


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## Robscix (Apr 15, 2010)

You don't have to turn it right to +14 as adjust to taste. I have been working with similar situation and found for my system that +14 puts too much bass on the Sat's.


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