SW-112 or SW-450

[Shodrewken]

Why buy one when you can buy two, for twice the price~ Yeah man if you can swing another one, a second sub will even out response and if I remember correctly will add another 3db to the sub sound level.

[Hutch1814]

I dropped the gain all the way down to just a nick past half way and lowered the sub level in the receiver (totally forgot I had it up to make up for the PDR-10 I was running) and just slightly moved the volume on the sub to a little past as well. Sounds much better, kid is sleeping so I can't really do much until he wakes up. Ill keep everybody posted on how it sounds.

[derrickdj1]

My level in my avr goes to -12db so I try to get my sub as huh as possible with my avr correcting it down to -11.5 db. Then it's perfect.

Getting the avr down to -11.5 means the gain is to High. The -3 to 0 range allows safe headroom to adjust the sub up or down from the avr. After autocalibration it is best not to adjust the gain on the sub and make adjustments from the avr. Cutting the gain to high on the sub can cause distortion, clipping or bottom out.

Playing with the gain control will not make the subs max spl any different, if it is a 115 db or 120 db, that is all the sub can do, which is intrinsic to it's design and components.

[Scrappydue]

My level in my avr goes to -12db so I try to get my sub as huh as possible with my avr correcting it down to -11.5 db. Then it's perfect.

Getting the avr down to -11.5 means the gain is to High. The -3 to 0 range allows safe headroom to adjust the sub up or down from the avr. After autocalibration it is best not to adjust the gain on the sub and make adjustments from the avr. Cutting the gain to high on the sub can cause distortion, clipping or bottom out.

Playing with the gain control will not make the subs max spl any different, if it is a 115 db or 120 db, that is all the sub can do, which is intrinsic to it's design and components.

that contradicts 100% on how I was told to set my pb-13 ultras from the guys at svs. They explained to me that a sub can only play as loud as the gain is set on it no matter what the avr is set on. So if an explosion goes off and my rt-10d is half way then it can only play half way. Now I can tell you that that seems to work out fine with that sub. I can play at reference volume on avr and the sub is fine. I have set up many different subs in the past year and every single one is different. I run the new svs ultras and I run the gain at 95% and they calibrate beautifully like that. Just found my best friend an ultra with the old bash amp and to get it to calibrate I had to run it at about 30%. It all depends on the amplifiers gain adjustments and how sensitive the voltage from the incoming source is

[Coleman]

I was also told after calibratiing that the sub level target range should be between -1.5 to +1.5. I have my sub volume at -23. Even if i set the sub at -10 the setting after calibration on my Denon is -12db which I was told is bad.

[Youthman]

I run the new svs ultras and I run the gain at 95% and they calibrate beautifully like that.

Wow, I'm no expert on sub setup but I've never heard anyone setting the gain at 95% on a sub amp. I've always set mine around 1/2 to at most, 2/3 gain and adjusted in the pre/pro to match the volume of my other speakers.

I was however advised to turn the gain all the way up on a QSC amp I tried out on my setup a long time ago. I guess that's the way you run professional amps?

[derrickdj1]

The preamp makes things more complicated: it depends on how variable the signal is versus a static constant signal. Mordern avr's are variable and that is why MCACC or Auddysee will suggest turning down the sub gain. The avr sub setting should ideally be -3 to +3 so adjustment can be made in the avr to increase or decrease the sub volume. The main point is that a given sub has a max spl or extension and no more can be squeezed out of it. From what I have seen on the forum, most people subs are fine for HT. IMHO the gain should never go over 60-70%. Someone once said there Epik Empire bottomed out, that should never happen with any movie if the sub is setup correctly. Some people think the new Tron movies is sending some LF and it is causing the sub to malfunction, it is not the sub but the movie.

For example, a gain of -10 will cut the preamp signal when trying to adjust the system to Reference leve and a gain of +10 will cause the preamp to increase the signal. I think I said that correctly.

[ivanhurd]

My Denon had me set the sub at 75 db (I think) before I could even run calibration.

[Hutch1814]

And I'm completely lost on all this -10 stuff, wish I could comment BUT I can't

[Scrappydue]

My Denon had me set the sub at 75 db (I think) before I could even run calibration.

when I first bought my ultra the guys told me to disregard my avr if it told me to do that. Now I have an older version of audyssey so it doesn't not. However that is how I was advised to do so with my svs because they have an extremely advanced dsp with very good limiters on them (at least that is what svs told me). I have already found the limits on my buddies svs with the gain at 30%. Mine however have not seen their limits. Maybe one of these day ill try derricks way and cal it to zero in the avr. But I would think the volume on the amp would not allow it to play very loud. Maybe that's just my logical thinking side.

[ivanhurd]

I would think that it wouldn't really matter either way. Your AVR is going to set it at a certain place anyways, so whether your AVR sets it at -10 or +10, it should still blend with the rest of your speakers the same. I would think it would be a good idea to turn the amp up on the sub at least halfway just because if the power is set too low, it could put a strain on the subs internal amp.

[derrickdj1]

Here is an example of a varible input signal:

[derrickdj1]

Here is an example of a static input signal:

[derrickdj1]

As can be seen in the third diagram, a low gain setting with a higher input signal can still reach the max spl. In essence most of us don't know what our safety margin is depending on the gain setting on the sub. Using autocalibration with the sub near 0 allows you to increase the sub volume by 3-6 db safely. I deally you should not loose bass in relation to autocalibration at high or low volumes. The bass should remain in the correct proportion. A really low input signal may make the auto/on feature not work properly.

Looking at all 3 diagrams, the same spl level can be achieve by an inverse relationship between the gain setting and the input voltage. The max spl stayed the same.

[Scrappydue]

Well I don't know anything about your graphs but I know what svs recommended to me makes the most sense in my head and all my stuff is calibrated the same as yours except my gain is way higher and my avr compensates. My subs go boom when they should and are quiet when they should be so that is always the way I reccomend friends to set them up. Could be bad gauge for people with cheaper subs that don't have limiters or clip easily. I will take that into consideration next time I'm giving my 2 cents. Thanks for the pics derrick

[derrickdj1]

Those subs you have are top notch and should be phenomenal for HT and music. There is alway more than one way to skin a cat! The things I mention are general statements and guides that I have use and learned They are only food for thought. I like the theory as much as the sound on how audio gear works.

[Hutch1814]

Well I've tried and tried to tame his sub, it's either there (well known) or I'm struggling to hear it. It's sitting in a corner, about 6 inches from the side and maybe 2 inches from the back wall. If I move it to the other side would it help? The other side is open to a door way and I'm hoping maybe moving it over to that corner would help it. I'm also considering moving behind the couch, can't stare at it back there but maybe it'd help break up the boom from it. Gain is 1/2 and power level is just a smudge pass the 1/2 way. I also have the sub settings set in the receiver to even (0 I think is the correct term) also have the sub phase set to 180. Any ideas?

[Youthman]

Well I've tried and tried to tame his sub, it's either there (well known) or I'm struggling to hear it.

That's not uncommon for a single sub. You will have spots in the room where you get good bass response and other spots where you are in a null. Have you tried the sub crawl? Put your sub in the main seat, crawl around the room and listen for the smoothest bass response. That's the best place to place your sub. Adding a 2nd sub will help smooth out the bass throughout the room.

[MichaelandKlipsch]

HEHE. With 4 THX Ultra 2 KW 120 subs I had to set my gain down to about 15% lol. but I will say (and I have read this many many places before) I have had those subs with the DB vol at about -2db on the AVR and the gain at 75% for some intense movie watching an no matter what I throw at them there has never been distortion. Every other sub I have owned you can get distortion at high volume levels. Not once have had a distortion problem with those 4 subs. I watched The dark knight also not to recently on them and at id say 70% gain on the 2 KA-1000 sub amps and @ -2db on the Pio eltie with Boundary gain compensation off my god I thought a poltergeist was pushing me back in my seat. They are the only subs I have ever listened to including (2) SVS PB ultra 13s Epiks, and JL Fathoms that can match that bass at the IMAX theater.

So although SVS, EPIK and JL make some incredible subs IMO. THE THX subs from Klipsch hold the bar high up.

[MichaelandKlipsch]

I will say with higher end up subs like the SVS PB Ultra 13s or the Klipsch THX KW-120s paired with KA-1000s the distortion is almost non-existent anymore. I have had my gain up to 90% with the DB rating at +4 and +6 on my THX subs a few times with near reference volume and still there is no distortion. They are over the top in their engineering.