Official SVS Owners/Support Thread. - Page 308

First off you room looks fantastic.

When I had my single sb12 I has the same feeling. I lived it for a short while. Then kind of forgot about it and was never wowed. Now I traded up to a pb12 it's been over a month and I am still giddy about it.

Your room is much bigger than mine Sony am not sure the 2 sb12 is enough. But you will DEFINitly get more output and extensions from the ultras and you will never get the grinning your face.

Kamiraa -- yeah again love your room I read your post with interest and mixed feelings. I just upgraded from a single SB12 to dual PB12-Plus, but I have yet to install the second one due to complications. Your room doesn't look like it's excessively large -- I don't think it's way larger than my 1600 cu ft living room -- so I can relate. By the way, I don't think it's necessary to upgrade to the Plus to obtain good bass: as I said earlier, I found my SB12 had better bass than my Plus at first, before finding the best location for my new acquisition.

On one count, with one sub in a corner, I found out that precise location of the sub has a large effect on the bass at the listening position, especially if the listening position is not close to one of the walls. My listening position is almost right smack in the middle of the room, which is a bit difficult because there is typically much less bass there. Anyway what I found out is that minute variations on the sub position (we're speaking a single inch here) can really change how bass is perceived in the middle of the room.

So this is meant to give you some hope: maybe by nudging your corner sub only a bit can you get a dramatic improvement. But on the other end, you have two subs, and my goal with duals would be to remove that kind of silly attention to details necessary to get outstanding results. I thought duals would translate into a pretty good bass field everywhere without spending to much time tweaking their position, but it seems it may not be the case.

You said you took measurements of the frequency response, but do you EQ your subs? (or does your AVR has MultEQ XT?).

Finally, note that the chest thump effect is mainly mid-bass, lots of it. So having a bigger sub that can output lots of SPL around 80 Hz would be best for that. Compared to the SB12, the Plus certainly imparts more movement to my hardwood floor and kicks my chest more efficiently. EQing the sub with a gentle house curve that reduced mid-bass quite a bit removed some of that chest thump effect but resulted in a much more balanced sound IMHO. I have not yet identified the frequency boost that I get from my current sub location that I like so much. It's lower than the top range, but its way above 20 Hz since I hear it in (non-dubstep) music. I'd say maybe 40-50 Hz tentatively.
Edited by neutro - 12/2/12 at 5:18pm

Thanks Brian and Neutro for the kind compliment!. It's a work in progress that's for sure. I added the velvet drapes this weekend, and moved the subs. Adding a blu ray open cabinet next weekend, some decorations, and a candy stand haha.
I'll need some help shortly on my acoustic treatment options (if there is any since the room is pretty open)

The room is aprox 2600 ft^3 (approx 14.5x20x9) , the wide angle DSLR lens is pretty deceiving. I think also a problem is the side to the room is wide open (stairs)
Here is a picture:


Yes the AVR is a Denon AVR-4520ci , which has XT32, and the dedicated bass EQ for both subs when it pairs them.

When I was doing measurements though it was just a single sub in the seating location, plugged through my laptop, with gain set to 50% max.
My goal was to find the smoothest area without an EQ, so in hopes when it was processed by the Audyssey XT32, it wouldn't need to much of tweaking to achieve great results. With that being said when it's post processed through Audyssey it does help the room, but you can't tweak much to what isn't there to begin with with (below 28hz).

Maybe i'm asking to much of the room? After doing the Sub Crawl, and Audyssey recal the room has considerable got better (watched two movies today). Problem is, for an engineer, I think there is ALWAYS more left on the table (maybe with a different model??)

Those speakers are very sexy ^^ is that a projection screen? or a Flat panel wall mounted...if so...what is the throow distance?

also just read this guess I should have known this but forgot abou it :
with this info, I am getting MUCH higher spl in the low teens than I thought...If I was getting 65dbs at 10-12hz I must be getting much higher...is there a chart for these corrections somwhere? I knew my room gain was awesome! audyssey does some fantastic things! LOVE MY PB12!!!!!

I'm no expert on that topic; but there is very few acoustic treatment options that work for sub frequencies. I think corner bass traps -- which can be a few inches thick -- can help a bit, an lots of people like adding a sub riser. They either do it themselves or buy an Auralex Subdude or Gramma Pad. A sub riser can 1) act as a bass trap itself, 2) decouple the sub from the floor and 3) get it out of the intersection of the wall and flloor by a few inches. I for one used an acoustic rubber mat meant to be put under hardwood floor to decouple my SB12 from the floor and I noticed much less rattling with it.

Yeah the room is bigger than I thought (and quite a bit bigger than mine). The fact that it is open probably doesn't help, since the stairway is a huge connecting volume. Still, it's not like you have a cathedral ceiling 5000 cu ft room to fill.

That's nice; so the subs are EQed, and since that AVR has full XT32, chances are any phase issue will have been dealt with during calibration.

Well that is how to do it. Do yo see a strong dip in FR below 30 Hz? I'm a bit curious because my room actually provides lots of gain there and using a single SB12, it was surprising how low it could go. You're right that EQing has its limits; it's also depend on the volume you want to reach. What I observed with the SB12 is that the blend was perfect at moderate volumes -- I EQed quite heavily, and the SB12's DSP alreay boosts the 20 Hz region. That used up quite a bit of headroom, and when I pushed it to -15 to -10 dB from reference (depending on the content of course), the limiter would enter into action and compression was audible. At higher volumes, the SB12's natural sealed FR begins to show and you get lots of 40-80 Hz content and much less sub-40 Hz content. Your dual setup will add 3 to 6 dB before the same happens. Do you feel the subs are lacking equally during moderate or high volume listening? Are the limiter LEDs blinking a lot or lit continuously? If so, you may want to consider an upgrade; but if not, I'd try to work a bit more. I say this because switching my SB12 for a PC12-Plus did not suddenly change everything. I had the same sub position problems, and while the new addition sure is more authoritative, I think it really shines mostly at higher volumes where the SB12 was simply out of steam. Below that, the SB12 was missing maybe a 5 Hz range (still half an octave at 20 Hz!) but the 15-to-20 Hz range is rather subtle at low volumes anyway, so the difference between the SB12 and the Plus is not that large at lower volumes.

Welcome in the club! It's very tempting to see what bigger models can do, and it's why I've ordered dual Pluses. I'm still waiting for the second one but I think I realized that I'm not sure what to expect anymore. If I want more effects from the sub, then I must turn up the volume: I'm pretty confident that at lower volumes, the SB12 was 90-95% there, and at higher volumes in my small room, dual Pluses will be 150% there The trick is, upgrading from my crappy old 60W 8" sub to the SB12 was a night and day difference, and I think I was half expecting the same from an upgrade to the Plus. However the advantages of a bigger sub show up differently: much more subtle at lower volumes (a bit more extension, a bit more slam), and it reveals itself at listening levels that I have rarely explored yet (as I mostly listen at -20 dB from reference in order not to wake up sleeping toddler & girlfriend; not a personal preference ). I really look forward to see what differences a second sub will make in my room.

So what I'm trying to say is, if you use your subs well below their limits, try boosting the low end (using the available headroom to give more 20-30 Hz content -- can you do that in your AVR?). If you consistently hit the limits, then yes, an upgrade may help you because when the limiter operates, you're actually wrecking havoc with your EQ, which may explain why you "first" (during EQ or at calibration levels?) felt it was ok and then got unsatisfied to "more" (at movie-watching levels?) you listened to it.
Edited by neutro - 12/3/12 at 9:28am

Yes! HTS has calibration files for the RadioShack SPL meter. In general, FR measurements without taking account the mic's calibration can be considerably off. If you're using REW there's a place in the preferences to load the file and take it into account.

ok so entering manually what I measured...this is unbelievable!! i had no clue I was this flat down to 10HZ...i knew I had good room gain but wow!!

EDIT: that big drop off is just having not measured over the subs crossover...can this chart be accuarate
?

I am going to have to run REW now to confirm haha

Brian, not that I'm jealous or anything but yeah a REW measurement with the calibration file loaded will yield more credence to those results. The reason why I'm a bit skeptical is that the PB12-NSD is ported and below the tuning frequency (19 Hz I think), it should drop faster than the SB12. Mind you, the SPL at 20 Hz is so high with respect to the SB12 that even at 15 Hz you'll have more output with the PB than the SB, but the drop is really sharp, at 24 dB/octave at first; then you hit the HPF that the DSP applies to protect the driver since the cabinets unloads below tuning, which adds *another* 24 dB/octave to the slope for a very sharp 48 dB/octave cut-off. This is visible in the REW measurements I took last week (although irrelevant because at that point the SPL is negligible).

(BTW it took me a while to understand that phrase: "the cabinet unloads below tuning frequency". What that basically means is that higher frequencies simply cannot travel to the port because the mass of air in the port is not able to vibrate fast enough: the high frequencies simply don't go through because they're damped by the air in the port. At the tuning frequency, the the mass of air in the port swings back and forth in resonance with the driver, and the wave escapes; the length of the port is adjusted so that the output of the port is in phase with the wave from the driver, and there is constructive interference. Below tuning frequency, the port is basically the same to the driver as an open cabinet, and there is simply no resistance to cone movement. This is dangerous because the driver is built to have some sort of spring-like resistance due to cabinet back-pressure. Thus to limit possible damage the DSP applies a high-pass filter that limits the cone's amplitude below tuning frequency.)

Im not skeptical because I DID reach 60db at 10hz and 65db at 12hz. I just dont think the correction values are accurate

Well if you have 100 dB at 20 Hz and you cut 24 dB/oct you still have 76 dB down at 10 Hz But I think the HPF kicks in much earlier (maybe 15 Hz), so your 60 dB figure is entirely believable. The thing is, when you have 100 dB from 20 to 100 Hz blasting, chances are you'll never notice 12 Hz content playing 30-40 dB quieter.

all valid points except for that "quieter" 10hz wav simply moving the floor. IDK its so funny. Idont really care ultimatly what i get as long as me loves its. haha. though it would be nice to be flat down to say 5hz! haha someday

Well if the tone is alone I guess you can hear / feel it. But move the floor I've not tested sub-20 Hz tones at loud settings to be frank. At low volume they sound like puttering, p-p-p-p-p, simply slower and slower as you reduce the frequency. I suspect what we're hearing is distortion/harmonics: the waveform as played by the woofer is not a perfect sine anymore (because of the filters and inherent limitations of the motor) and thus, it can be thought of as a 10 Hz fundamental and higher-order harmonics. Those harmonics at 20, 30, 40, etc. Hz are themselves audible.

That being said, what do I know. Maybe I just need to crank up the volume and try 10 Hz tones But even with the limiter in place I do fear a bit for the sub I admit. Dropping 800 W into a coil that can't follow up doesn't seem the brightest idea. Maybe I'm just too afraid of the warnings before the tones

It's a 110" Screen Innovations Black Diamond G3 1.3 Gain Screen, powered by the Sharp Elite XV-Z1700 3d Projector on a Chief Pro mount.
Throw is around ~13.0 feet (screen to lens tip). It's ISF calibrated to put out over 1000 lumens with both iris's on.

Seating distance is approx 12 feet (slightly more when reclined). THX rules state 0.85 as the multiplying factor.

12" = 144 which says I could go 122" in screen size, we tried to mask it in the room and seemed slightly to big. 110" was the compromise, which is pretty immersive.

Been in talks with SVS, I may just upgrade to the SB13ultras (two of them), or just a single PB13Ultra for the time being . . when I move I will be building a bigger dedicated (closed) theater room, and just go to TWO PB13Ultras . . . *druel*

A big question is . . . is a lot of movies encoded down to 15-30hz or am I chasing an "number" here??? Because if not, maybe I should just stick with the dual SB12's which are performing really well now 30hz+ now with the move and recalibration of Audyssey.

20-30hz yes lots of movies with these frequencies.

<20 not so much. But when they do. Oh so fun!!!

<20 only fun if you have enough output (spl) to feel it.

I was discussing this with a co-worker (who, incidentally, decided to buy my SB12 -- not a done deal yet but a statement of intents) and what we really, really need, is a dvd or blu-ray full of *real* ULFE scenes to show off and test. Tones are no fun, and for lots of the 4-to-5 star movies what we really want is *the* scene (aquarium tapping in Finding Nemo, pods emergence from WotW, crash in FotP, depth charges in U-571, etc.). Actually we would need so little material from each movie that fair use could logically apply to that kind of project.

As a starting point I was looking at DVD rips (downloaded none, I swear) and they're often downsampled to stereo. In my experience the stereo soundtrack is *much* less interesting in the bass department. Not sure why this is though. Does the LFE channel add dynamic range or something? Anyway I don't really have time to look into the legality of building such a DVD or blu-ray image, I guess it would be a nightmare. But it would really be so much easier to hear and compare what we're talking about in these forums without investing hundreds of dollars on blu-ray that we have already seen -- or in some case that we already own.

When I have 10 mins alone in my living room with the girls out, and want to test what a scene sounds like at reference level, I don't have time to rummage to my collection, pop the blu-ray, browse the scenes and start it, and do it all over again to hear the next scene.

Sorry for the rant

Have you checked the "Reference Blu-Ray Demo Disc" thread? There is a specific segment just for bass.

I guess my idea isn't new is it? I'll take a look

Probably not, but is a good one.........

Looks like I should shop for a BD burner now

True. And I do so it's fun

Good thing is that they are really cheap now!

One more thing, if eventually you are going to make your own copy, please make sure to buy a rewritable 50GB bluray. So, if for any reason you have issues during the burning process, you can easily format the disc and try again.

Good to know. But if my WDTV can read the m2ts files themselves, maybe I won't even have to burn a blu-ray. Also I think XBMC might be able to read iso images-- just not sure about blu-ray images.

Guys, so iv been playing some more movies and music with the new pb12 NSD, at times, the bass can be slightly boomy, the system is calibrated with auddysey xt32.

now, could it be that im interpreting this as being boomy and this is how bass is supposed to actually sound? because i never really had such a high quality subwoofer before? (i had the eD A2-300 before and before that i had a HTIB Onkyo sub)

i definitely hear more detail in bass now that i wasn't hearing previously, specially in Music. i can hear every beat, it can be slightly overpowering though at times..

should i lower the volume of the subwoofer on the reciever a bit ?(the auddysey calibration set the volume of the subwoofer to +0.5db)
Edited by lamonsasa - 12/3/12 at 9:11pm

Do you by chance have an SPL meter? While Audyssey calibrates their mic's, I've found them to have a bit more fluctuation when setting levels then I would like. I have a AVR-4311Ci w/XT32, and have the opposite problem, Audyssey tends to set the combined level about 2-3db too low. Different issue, but perhaps the same cause and the same remedy, measure and adjust.

what movies are you watching? just to get an idea of the content

you may have a room peak in the midbass regions where bass is most common thus causing the boom sound. do you have it corner loaded? while improving output can sometimes cause boomy sounds

Unless you have a very well calibrated spl meter your not going to get anymore accurate than the audy. mic. typically they are within -/+2dbs. for instance a RS meter is worse than this.

I played dark knight rises blurry, u571, the expandables 2, with music I played Kenny g, then some dance music like skrillex.

I do have an spl meter, what should I do? Run a test tone on the subwoofer from my receiver? What should the spl meter read?

Oh and the subwoofer is in the corner, it's in the same corner where the Ed a2 300 was, and I didn't have boomy bass with the Ed

It can't be that my pb12 is defective in any way right? I mean that has nothing to do with the boomy notes right?

Good afternoon colleagues, good afternoon here in Spain, of course.

I just called to let me know in the carrier in 1h or 2h, will come to leave my house my new PB12-Plus DSP, so I'm crazy for it to arrive.

Later delight them with some pictures of my new beast.

A hug.