SVS 20-39 PCi... wow... (1 Viewer)

[Willem Vos]

I used to have a REL Q150 subwoofer, which is a sealed 10inch sub.
I sold it, because it was inadequate at playing my new dvd's, specifically Lord of the rings. After that I knew I needed something a lot more powerful. I looked around in local shops, and the only thing available in my price range was the Yamaha YST-SW800.

I finally decided, even though the shipping and taxes made it the more expensive choice, on the SVS 20-39PCi. The positive reviews I've been reading on this forum really convinced me that SVS was the best choice.

I didn't choose the PC+ (although I was tempted), because I have a very small room (less than 1400 cu. ft.), and because the total cost would have been more than $1100.

The PCi was delivered (flown in ) last week... and boy, is it BIG! Especially in my small room, this subwoofer tends to really dominate my entire setup (it looks really funny). But luckily, the sound is just as big as its appearance
Both music and movies now sound very good. I watched some scenes (Behind Enemy Lines - Sam attack blew me (and my brother) away) and they all sounded great.

I have got some questions though:
Has anyone ever bottomed-out his PCi subwoofer? If so, which scene, at what gain level on the sub and at what volume on the amp?
Ever since bottoming my old sub, I want to be careful not to go that far again.

Is it worth playing a frequency sweep? The only frequency sweep I have is from THX optimode, and that one goes really high (20kHz I think), so I avoid playing it...

Thanks

 

[Guy Usher]

In your small room it will be plenty load, I have a cs2039 in a room about 2 times larger and calibrated "Hot" (up about 6db from a flat response) I have never bottomed the woofer, sometimes it gets very load. Typically I am at -20 on volume with 86db speakers but on occasion I will play a movie at -10 to -5, still no problems. I have played LOYR at -10 which is really too load for me.
I found that I kept turning the sub down as it broke in. I would make sure you calibrate it with a SPL meter and give it a little time to loosen up at the same time you are getting used to it. I would slowly work up the level untill it suites you listening carefully for distortion (which comes first) then bottoming out which you dont want to make a habit of. Really this is a question for SVS, I mean for signs of distress.
I can say I have had no signs of distress and I am using a 450 real watt amp, however I play it to suite my family not to impress my friends (which it does BTW)
BTW I am happy to report for the first time in years I now have a flat response from 1K down to 20hz, by flat I mean within 2db, it is so nice not to have the 50-60hz bump that I had for so long. Actually I had gotten used to it so at first the SVS sounded a little thin, not now since I have got used to what it is supposed to sound like, no more listener fatique(sp)

 

[Mark Zimmer]

I've never bottomed out my PCi, even on LOTR at reference. I've heard, though, that it has limiters that prevent you from bottoming out (not an issue with the CS), so that may be why. I've not noticed any distortion or clipping that one would expect from a limiter though.

 

[keir]

pci has no limiter, it has a subsonic highpass filter so the sub does not try to play any bass lower than its tuning point (which is a main cause of bottoming out). i have never bottomed out my 16-46pci either.

 

[Rudi B]

I looked around in local shops, and the only thing available in my price range was the Yamaha YST- SW800.

Did you perhaps audition this one? I currently have it and I'm VERY tempted to get a 20-39PC+ (with all the high taxes and customs and shipping to Europe) ... I'd like to know just how much better SVS'en are compared to this one, and if they justify the high extra shipping & other expenses (~$400) ...

 

[Willem Vos]

Did you perhaps audition this one? I currently have it and I'm VERY tempted to get a 20-39PC+

I have never auditioned the YST-SW800, but I've seen it, and the difference in size between it and an SVS 20-39 enclosure is very big indeed. I'm not sure if an upgrade is justified for you though... it would probably depend on your room size. In a big room there will probably be a big difference.

BTW, I managed to run a frequency sweep at low volume -35 (200Hz to 20Hz) several times, and I have a big dip, followed by a peak in the middle(?). My crossover is set to 80Hz, and the SVS' crossover is disabled. Is this dip caused by the fact that the SVS is standing in a corner?

 

[Tyler DJW]

Hi Willem,
If you've got a dip around 80 and a peak around 40 then you've got the same problem I do. It is caused for me by standing waves in my listening position. All I can really do is sit off-centre to help balance out the sound. I find it distracting in Lord of the Rings because the frequency sweep when Sauron croaks in the prologue starts fairly quiet and then gets much louder at the end.

I would play around with room placement. I moved my SVS 20-39PCi from the corner to about 4 feet from the corner on one wall and it helped balance it out. Bottom line, it is more likely caused by your room than the sub itself.

 

[Willem Vos]

Thanks Tyler, I'll have to try moving it around.

Is it normal for that frequency sweep (THX Optimode from Phantom Menace) to pop slightly at the end? Or am I overdoing something with this frequency sweep?

Is it at all possible to damage my speakers or sub by doing multiple frequency sweeps (20-200Hz)?
I know from my previous subwoofer that leaving a test tone running on a sub for a long time can cause the internal amp to get very hot...

 

[Willem Vos]

bump

 

[Tyler DJW]

Is it at all possible to damage my speakers or sub by doing multiple frequency sweeps (20-200Hz)?

If someone else knows better please step in, but I don't think there's any harm in this. I wouldn't do it for hours on end, but it was really helpful for me to set up my sub.

As a side note, I would consider getting AVIA to help set up your sub. Some of the tests I found helpful were the wobble tones and the 200Hz-20Hz frequency sweep where it shows you the frequency on screen at the same time. The latter one helped me identify where exactly I was having problems. The S&V setup disc doesn't have these exact features and I'm not sure about Video Essentials.

The following link has a great guide to using the AVIA disc to overcome some of these problems... best of luck.

FAQ AVIA

 

[Willem Vos]

Thanks for the reply Tyler.

The AVIA disc always seemed too expensive too me, but I guess it's essential if I want to know exactly what's going on.

I must have ran the THX frequency test about 20 times (had to skip through all the menu's each time to get to it, very cumbersome) each time experimenting with the crossover (had it turned off) and phase switch.
But it doesn't give you any info on which frequency it is testing... pretty useless, although it did tell me that there IS a dip.

It's pretty hard to move the PCi, it's in its intended location, and everything else is sort of built around it . Would moving it from the right-front corner to the left-front corner help eliminate the gap?
The sub sounds very good, but eliminating the gap will probably make it sound better, right? I'm very pleased with the sound as is, so I'm not sure if it's worth fiddling with any further...

 

[Guy Usher]

A little trick that works for me on sub placement; put your sub in the place where you will be sitting and then walk around with the SPL meter untill you find the spot where it is loadest, put your sub there, a lot easier than moving a big old sub all over the room. when your wife asks "What in the hell are you doing"? tell her you are doing a survey for the forum, you wouldnt want to get caught doing something silly on your own. . .
Works for me, better than sitting crooked while watching a movie, makes my neck hurt. . . .

 

[Tyler DJW]

That's good advice too. I've never tried it myself, but I've heard it suggested before. I eventually had to settle on my sub placement as well... it's not perfect but it's pretty close.

If you keep using the Optimizer frequency sweeps one thing I did was to find exactly what track and chapter it is and access it directly... that way you don't need to cycle through all of the other audio tests as well.

Even though I have everything set up it's still fun once in a while to just let the frequency sweep go and make everything rattle in my apartment (my poor neighbors).

 

[ChrisWiggles]

Willem, DO get the Avia disc, along with the rat-shack SPL meter. Its the best tweak you can ever do on your system. You can calibrate your speakers right, you can calibrate your sub right, and even more importantly, you can calibrate your video. I can't stress this enough, how much better you can get the video with a simple $50 Avia disk. I calibrate TVs for friends and such just cause I'm nice, and I walk in on really junky RCA TVs, that look hideous, the color looks bad, overly bright, and I dial it in with the help of avia, and it looks goregous.

Oh, and BTW, Avia has some bass sweeps that start, at something like 200 hz and go down, and it tells you the freq too, which is really helpful. And the other thing, subs can be VERY placement-picky. One foot CAN make a significant difference, and although I'm sure you're not too partial to lugging that SVS around the room, it can really help find that perfect spot. I remember once I was dialing in a crappy KLH sub for a friend, and there was a HUGE room resonance problem, and I moved it one foot left, and on the next sweep it was almost totally gone. Sure, 5 dbs up still, but much less than what it was before, and it was probably just mid-bass bloom from the cheesy sub anyway.

 

[Mathew Shelby]

I know you probably don't get this question very often, but what is the smallest subwoofer that SVS makes? Can someone please provide me with a link/pic?

 

[Tyler DJW]

Hey Mathew, if you haven't already check out the new thread in this forum about the SVS box subs... they're putting out their first box subs in the coming weeks and should be comparable in performance to the cylinders. The smallest cylinder subs are the 25-31 subs. Check out http://www.svsubwoofers.com for more information.

 

[Willem Vos]

put your sub in the place where you will be sitting and then walk around with the SPL meter untill you find the spot where it is loadest

That sounds like a really good trick, but it's not going to help in my situation I'm afraid. The sub has to stay roughly in the position where it is now. The most I can move it is 1 or 2 feet from the corner...

 

[Cees Alons]

Hello (hallo) Willem,

Yes but you can still do it (and perhaps also limit your wandering around to the places where the sub CAN go). At least it will make you think about it - and perhaps see a way to move it to the optimal place in your room nevertheless.

Cees

 

[Willem Vos]

Hallo Cees,

I've already placed it a little bit away from the corner.
The dip is still there, but much smaller (although I need AVIA to tell me more exactly where it is and how big).

Thanks for your advice all, I'm going to experiment further once I receive AVIA. For now, I'm just going to enjoy my SVS with some movies