Am I supposed to break-in my new SVS sub?

[JDawg]

I just received my new SVS 20-39PC+ last night and so far i'm really happy with it. I just watched Matrix Revolutions and there's a lot of bass in this movie I never noticed or heard before with my old sub. I'm not sure how to describe this but the only negative thing I've noticed is that I get some distortion during certain scenes such during the opening scene of Revolutions. I also noticed it during the THX intro in Star Wars Episode 1 and the depth charge scene in U571. I thought SVS subs were supposed to have very little distortion and I don't have it cranked up super loud either. So my question is will breaking it in get rid of this distortion? Otherwise the sub sounds great.

 

[Sheep]

Maybe its setup incorrectly? Push any sub hard enough and it will distort and clip. You're probably over driving the woofer. Adjust your settings and tuning.

SheepStar

 

[mtrycrafts]

I just received my new SVS 20-39PC+ last night and so far i'm really happy with it. I just watched Matrix Revolutions and there's a lot of bass in this movie I never noticed or heard before with my old sub. I'm not sure how to describe this but the only negative thing I've noticed is that I get some distortion during certain scenes such during the opening scene of Revolutions. I also noticed it during the THX intro in Star Wars Episode 1 and the depth charge scene in U571. I thought SVS subs were supposed to have very little distortion and I don't have it cranked up super loud either. So my question is will breaking it in get rid of this distortion? Otherwise the sub sounds great.

All subs distort as you increase their volume, except for that servo controlled Velo subs. If you ever notice sub reviews in Sound &Vision they rate their performance at 10% distortion. Why? Because at low frequencies distortion is most difficult to detect. Even at 100% it may be tough.
http://www.axiomaudio.com/distortion.html#

In fact, the “noise” tones at 20 Hz and 40 Hz had to be increased to levels louder than the music itself before we even noticed them.

So, It may be other issues? Driver bottoming when over driven?
Is your sub properly level matched with the other channels?

 

[JDawg]

I calibrated the sub to the same level as the rest of the speakers so it shouldn't be distorting because i'm not watching my movies that loud. I'll try adjusting it again to see if I can fix the problem.

Edit: I found out what the problem was. I was using a Y-connector before on my old sub and I didn't remove it when connecting it to my new sub. After taking it off and connecting the cable straight to one of the two inputs the distortion went away and now it sounds great!

 

[abboudc]

I calibrated the sub to the same level as the rest of the speakers so it shouldn't be distorting because i'm not watching my movies that loud. I'll try adjusting it again to see if I can fix the problem.

Edit: I found out what the problem was. I was using a Y-connector before on my old sub and I didn't remove it when connecting it to my new sub. After taking it off and connecting the cable straight to one of the two inputs the distortion went away and now it sounds great!

Stop now and read the manual It specifically mentions not to use a Y-connector. There are other things worth reading in there, variable tuning, how to use the EQ, etc, that will help you get the most out of your sub. It's not just garbage like most electronics manuals.

 

[JDawg]

I actually read the manual before using it but I was too excited at the time I hooked it up that I forgot about that. It wasn't until i was looking at my connections today that I remembered something about the y-connector so I removed it. Anyways its all good now

 

[JDawg]

Looks like I spoke too soon because I didn't realize that my sub was playing at a much lower level after removing the Y connector. After calibrating it again to the same level as the other channels the distortion came back. I'm not too happy about that so now i'm hoping its a minor thing that's easy to fix.

 

[Sheep]

Where in Vancouver are you?

SheepStar

 

[Nuglets]

What kind of distortion are you experiencing? Is it a buzz? Over-excursion? Clipping?

 

[JDawg]

I live in East Van near DT secondary school.

Well i'm not sure how to describe what kind of distortion it is. I think its called clipping or maybe the driver is bottoming out. Anyways my uncle who know's a lot about this stuff is going to come look at it today or tomorrow. I did manage to get the clipping/distortion to go away when I reduced the bass level a bit. I'm not sure if thats the same as lowering the sub level though but it seems to have worked for now.

Edit: I got a flashlight and watched the woofer during the scene where it distorts and it looks like the driver hits the base plate. So it looks like I just have to lower it a bit until it doesn't bottom out anymore.

 

[mtrycrafts]

I live in East Van near DT secondary school.

Well i'm not sure how to describe what kind of distortion it is. I think its called clipping or maybe the driver is bottoming out. Anyways my uncle who know's a lot about this stuff is going to come look at it today or tomorrow. I did manage to get the clipping/distortion to go away when I reduced the bass level a bit. I'm not sure if thats the same as lowering the sub level though but it seems to have worked for now.

Edit: I got a flashlight and watched the woofer during the scene where it distorts and it looks like the driver hits the base plate. So it looks like I just have to lower it a bit until it doesn't bottom out anymore.

What is the trim level at for the sub when you level match it? Maybe the volume setting on the sub needs to be higher thereby lowering the receiver trim level.

 

[Sheep]

How is the subwoofer setup? What tuning?

If it's 16 or 12Hz, I would recommend going higher so you have some more headroom.

SheepStar

 

[Rob Babcock]

There are two likely scenarios that occur to me:

1) You're overdriving your sub. No matter how potent the sub, it can be overdriven. The fact that the distortion went away when you inadvertantly reduced the input by incorrectly connecting it lends weight to this notion.

2) You're engaging a room mode with a frequency low enough that your previous sub didn't excite it. Room acoustics dictate the sound quality you get more than any other component in your system, perhaps including your speakers. Below 100 hz it's not uncommon for peaks and nulls creating a variation of 20 dB or more. An easy test would be to get a disc of test tones (cheaply obtained from Stereophile or Rives Acoustics, or from various websites at no cost) and an SPL meter (also pretty inexpensive from Radio Shack; it's not a lab grade instrument, but it'll get you in the ballpark).

 

[mtrycrafts]

There are two likely scenarios that occur to me:

1) You're overdriving your sub. No matter how potent the sub, it can be overdriven. The fact that the distortion went away when you inadvertantly reduced the input by incorrectly connecting it lends weight to this notion.

2) You're engaging a room mode with a frequency low enough that your previous sub didn't excite it. Room acoustics dictate the sound quality you get more than any other component in your system, perhaps including your speakers. Below 100 hz it's not uncommon for peaks and nulls creating a variation of 20 dB or more. An easy test would be to get a disc of test tones (cheaply obtained from Stereophile or Rives Acoustics, or from various websites at no cost) and an SPL meter (also pretty inexpensive from Radio Shack; it's not a lab grade instrument, but it'll get you in the ballpark).

I would pick number 2.

The first would be explained away in that he had levels matched, sub not seemed to be boosted above other speakers, and, he didn't play it very loud at all. So, either number two, or the input to the sub from the trims is high maybe causing overload levels on the input while the sub may not be overloading?

 

[kryolla]

You can try to turn your trim level down on your receiver and see if the distortion goes away or if you want to calibrate your sub get a Behringer Feedback Destroyer and you can mess with your trim levels and see where it is clipping at, once that done you can adjust the peaks and nulls with BFD.

Drew

 

[JDawg]

Well i've had some time to adjust the settings and what I did was set my receiver to the volume I normally watch my movies at. Then I played back the scenes where the distortion occurs and I slowly adjust the sub level until it went away. Now its a little lower but I still get strong powerful bass that can still rattle the pictures on the wall.