SVS SUB BETTER WITH LOW PASS FILTER OFF


After endless tweaking and experimentation, I have concluded beyond a shadow of a doubt, my system sounds profoundly better by turning OFF the SVS "low pass filter"! My amp has a sub out with a filter option set at 80 db's. Like all good audiophiles I carefully followed instructions, searched google to tweak all settings. I tried all variables in frequency. Until one fateful day, for no special reason, I turned it OFF. "WAIT", I said to myself. This sounds better. "Can't be!" "It must be boomy, or bloated, or congested .....or something bad. NO, it wasn't. It not only sounded more cohesive but the "hole" in the sound stage was gone. (I had a sense there was a perceptible hole in the musical picture which kept vaguely appearing which destroyed the whole overall enjoyment. I'm interested if anyone else has tried this heretical approach?

allears4u

What @erik_squires said is pretty much dead on:

The only heresy I know is trying to do this all without measurements first.  I mean, it's dogma, but I find getting this right by ear alone is so random. 

Bloom and bloat IMHO had more to do with room modes, where a little EQ can go a long long way.

Glad you found a setting that works for you."

 

I have a very odd shaped living room listening space, and the speakers are set in an odd spot.  I -need- a sub, but room nodes were a nightmare to figure out.  I found a website that you plug in your floor plan dimensions, and it literally shows you every frequency and where it nulls or blooms in your space. This helped me narrow down the worst frequencies.  Then my step dad made me an electronic notch filter and I could 'dial back' those specific frequencies to at least some extent.  Then I would sit and play each bass frequency, check it's level, tweak the notch filter, and adjust.  Like Erik said, it's basically doing some basic EQ tweaking. 

I will say that for the money, it pays dividends to find a mechanical mean to limit any bloom you have from the sub itself by moving it around to a potentially better location.  Again, web sites that plot room nodes can give you near exact spots.  

I'll be setting up a new system in a second location soon so keen on hearing about others' sub integration.  In regards to plugging ports in ported speakers as @erik_squires suggested, while this lowers the f3, doesn't it also lessen the effective roll-off slope at the low end?  Wouldn't a steeper one be easier to transition to a sub like the SVS with selectable slopes?  Also along these  lines, what role does the hack of adding straws in the ports make?  I thought this was supposed to de-tune the port's dominant tuning frequency while still allowing for the same mid woofer performance that the XO was designed for.  

Since most subs interact with mains like stand mounts around 80hz, and the "phase correction" on subs really operates as a time delay based on 80 hz, a setting around 90 deg should help mitigate causing a notch or a bloom.  All else being equal.  Room etc.  

Soon as I read the OP, I realized he has both crossovers engaged, preamp and subs, disabling one of them will produce the best performance. I have dual SVS SB2000 and was using a Halo HINT which has bass management system including high and low filters. 
I never used those as I sent my mains a full signal then set crossover on the HINT at 50Hz, the subs have to be set to LFE so they get a full signal from the HINT. If you wanna use the crossover on the subs then make sure the filters on the preamp are set to LFE or off if you can. 
Now I have a JC2BP which has no bass management system so the subs get a full signal from the Main outs, so now I set the crossover on the subs to 50Hz. 

doesn’t it also lessen the effective roll-off slope at the low end?

Yes, but by that time it’s all pretty low in level. The point is not that this should always be done but to try it and listen for yourself. In some cases this can even help with room related bass bloat. I’ve had one A’goner say that plugging 1 of the two speakers finally dialed in the bass for him.

This is a safe, reversible experiment. 

(To Josepad) So I will try and turn off bass bypass on my integrated so full signal is sent to my mains again and set "Low Pass Filter" on SVS Pro2000 at "ON". Then set SVS "Low Pass Filter" to 35 hz or so. Sound right?