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Official SVS Owners/Support Thread. - Page 339

post #10141 of 15588
Quote:
Originally Posted by JacobC1983 View Post

They aren't horrible, they work fine, but they have some patina

Well, before you get rid of your old subs, hook them up with your PB12's.
Run Audyssey and you'll be able to experience first hand what I've been talking about.
No way will I ever go back to running just two subwoofers.
What a letdown that turned out to be.
post #10142 of 15588
Hooking up four subs certainly is worth a try. However, one should be aware of the complexities of obtaining a flat response with more than one model of subwoofer.

Take a simple example: two different subwoofers having a flat frequency response from the crossover frequency and down. Subwoofer A is flat to 20 Hz and then rolls off below. Subwoofer B is flat to 30 Hz and rolls off below. Subwoofer A can play 115 dB SPL at 20 Hz. Subwoofer B can play 100 dB SPL at 20 Hz.

When playing so that each subwoofer has a 80 dB SPL output at the listening position, the combination of the two will provide between 83 and 86 dB SPL at the listening position depending on sub position, room configuration, etc., down to 30 Hz, under which sub B rolls off. From 30 down to 20 Hz, subwoofer A is more or less alone doing the job, barring room mode effects amplifying sub B. Thus the level will drop to ~80 dB SPL between 20 and 30 Hz.

To compensate for this, it would be necessary to EQ the subs so that a 3-6 dB boost is applied between 20 and 30 Hz. Some systems allow EQing the subs individually, but this is not standard, and it's generally not a good idea, as EQing with PEQ filters introduces phase shifts at cuts and boosts, and combining waveforms affected by different phase shifts will result in a frequency response that is not the simple addition of the two EQed responses. Thus most of the time, it is advised to EQ the subs as a pair. Note that even with Audyssey MultEQ XT32 with SubEQ HT, the dual subs will be EQed as a pair, but level and distance will be set individually.

Thus, EQing subs A and B as a pair, each should be boosted by around 3 dB between 20 and 30 Hz, so that their combination provides the 3-6 dB boost needed to obtain a flat EQ down to 20 Hz. In reality, since sub B cuts off at 30 Hz, the boost will need to be higher than that, since it will mostly apply to sub A, which is alone contributing between 20 and 30 Hz. So make it +6 dB, which sub B will also get under its tuning frequency. Now if you raise the volume by 20 dB, you hit the limits of sub B in the 30 Hz to crossover range. Unless sub B has exceptional protection circuitry (such as an SVS sub), the +6 dB boost under its tuning frequency will have long ago make it cry for help and generally produce audible distortion. Volume at the listener is 103-106 dB, a good 9 dB under the limits of sub A alone.

Now suppose that distortion and damage risk to sub B is acceptable for the listener, and he/she still raises the volume (note: SubEQ HT won't allow you to do that to protect sub B). Assume that sub B simply compresses, providing the exact same sound as before. Volume is raised by 10 dB more, i.e. sub A now provides 110 dB SPL above 30 Hz, and hits its limits under that due to the +6 dB boost. No more output is provided by sub B in the 30 Hz - crossover range, so that there's a 3-6 dB gap in that range. Since the 20-30 Hz range was covered by sub A alone, that range is now 3-6 dB louder than the rest of the response. Flat EQ is thus lost.

Compare with running sub A alone: flat EQ down to 20 Hz is achieved and conserved up to 115 dB SPL with no audible distortion.

The only thing that sub B provides in that scenario is a possibility to fill up nulls in the frequency response -- which is very nice, but comes with a *tax* on performances. Adding a second sub A instead of running sub B, i.e. using identical dual subs, the flat EQ down to 20 Hz is still achieved, up to 115 dB SPL + 3-6 dB due to duals (plus a flatter response to begin with).

Another way to integrate different subs would be to use different crossovers and possibly band-pass filters for each, but it's significantly more complicated. You might also always listen to levels below the limits of the most limited subwoofer, which alleviates parts of the problem described above (and is what SubEQ HT would force you to do), but begs the question of why using a more powerful subwoofer to begin with, unless the answer is that "it was just laying around". Finally, it might be that the basic FR of a single sub is so wrecked that the addition of a second one, even with the limitations outlined above, is a better overall solution than the single more powerful sub. The discussion above also applies to dual SVS + dual Klipsch subs.
post #10143 of 15588
Audyssey with MultEQ XT32 and Sub EQ HT did a superb job, in seamlessly blending together
my two ported and two sealed subwoofers.

Prior to running Audyssey, I individually leveled each sub to 75dB, as instructed to do so by Audyssey.
Then I ran the full 8 position Audyssey calibration.

I now have plenty of tight, tuneful, reference bass. cool.gif

Thanks Audyssey!
post #10144 of 15588
Quote:
Originally Posted by neutro View Post

The only thing that sub B provides in that scenario is a possibility to fill up nulls in the frequency response -- which is very nice, but comes with a *tax* on performances. Adding a second sub A instead of running sub B, i.e. using identical dual subs, the flat EQ down to 20 Hz is still achieved, up to 115 dB SPL + 3-6 dB due to duals (plus a flatter response to begin with).

Another way to integrate different subs would be to use different crossovers and possibly band-pass filters for each, but it's significantly more complicated. You might also always listen to levels below the limits of the most limited subwoofer, which alleviates parts of the problem described above (and is what SubEQ HT would force you to do), but begs the question of why using a more powerful subwoofer to begin with, unless the answer is that "it was just laying around". Finally, it might be that the basic FR of a single sub is so wrecked that the addition of a second one, even with the limitations outlined above, is a better overall solution than the single more powerful sub. The discussion above also applies to dual SVS + dual Klipsch subs.

What is missing is the fact that despite a movie sound track being mixed to THX standards, only 0.01% of movie volume in a theater is +90 to 95 dB(A).

"Cinemas - do they pose a risk to hearing?"

Quote:
Furthermore, for all films except The Siege, sound levels exceeded 90 to 95 dB(A) for only 0.01% of the time i.e. less than 10 seconds.

Your originally above quoted comment is how I see the mixing and matching of dissimilar subwoofer capabilities; subwoofers cost too darn much! tongue.gif) The intent of the "MUCH MORE" capable output of the superior subwoofer is to extend low frequency content into the sub-sonic range and the purpose of the inferior subs is to fill in the nulls, improving mid-bass slam in the process at considerable savings to the Home Theater owner.

Example, a pair of Klipsch, RW-12D's coupled with a SVS, PC-13 Ultra or a Rythmik, FV15HP. In my mind's thinking, if doing this, one would have a very capable three subwoofer system that will have flat, mid-bass. But in coupling the less pair of subwoofers with a "MUCH MORE" capable subwoofer, when the crossover takes place (the two lesser subs drop out due to limited capability), coupled with the above <100 dB movie theater analysis, one will have and an "economical" solution to the dilemma of subwoofers cost too darn much! My bet, much of mixing and matching subwoofers revolves around cost as not everybody can afford three or four Funk Audion, 18.0C's and not many wives are going say, oh heck yeah, do it. tongue.gif But a couple of lesser subs, coupled with a "MUCH MORE" capable subwoofer will give the user what they want; strong, flat mid-bass slam coupled with lots of very capable sub-sonic rumble.

(Now that's what I'm talking about.)

As to the question; why do it? For many, including moi, we already have two less capable subwoofers in position but costs being what they are, with upgrades for television, center channel, amplifier, AVR, any necessary cable changes, testing gear, et cetera, affording one "MUCH MORE" capable subwoofer is all many of us can afford.

Oh boo-hoo me. tongue.gif

-
Edited by BeeMan458 - 3/22/13 at 10:21am
post #10145 of 15588
First of all, sorry if I offended anyone with my comment. If I had dissimilar subs, I'd *sure* at least try running them as a pair. Subs costs lots of money so if they're laying around, why not use them. The whole point of my analysis is to underline the problems that this solution might incur. I'm a bit pessimistic in nature, so maybe it's easier than I imagine to get right. And this is a pretty major disclaimer that I should make: my current setup with identical dual subs is the first time 1) I try duals and 2) I use "real" subs. I've never tried mismatched duals.
Quote:
Originally Posted by coolcat4843 View Post

Audyssey with MultEQ XT32 and Sub EQ HT did a superb job, in seamlessly blending together my two ported and two sealed subwoofers.

I can only extend two thumbs upward to that. Another disclaimer: I actually never tried SubEQ HT, nor MultEQ XT32, nor Audyssey in fact. I'd love to.

Maybe you're far from both sub type limits, and maybe their individual FR coupled with your room response just fit together nicely. This is important as room response will 1) wreck the sub's flat response to begin with and 2) will act differently on every sub you have since they're not all at the same location. So there's wiggle room with respect to the textbook scenario I described above to find circumstances in which multiple mismatched subs could help.
Quote:
Originally Posted by BeeMan458 View Post

What is missing is the fact that despite a movie sound track being mixed to THX standards, only 0.01% of movie volume in a theater is +90 to 95 dB(A).

Agreed, but note the following points. First, this probably applies to the front, center and surround channels. The LFE channel is typically played 10 dB louder, with a max of 115 dB instead of the 105 dB for the other channels. Also, enthusiasts -- and they are many in this thread -- often run their subs hot by several dB. Boosting the LFEs is mainly an addition to the tactile feeling, and does not really interfere (hide, swamp, whatever) with the other channels. Even running the low end (<30 Hz) hot by +6 dB, what hurts the ears are the highs (e.g. crashing windows), not the seismic rumbles. In that regard, the subs do play louder in average than the figures quoted above. I'd say they also play at close to max for a bit longer than 10 sec per movie, but 10 sec or 30 sec, the fact is that it's the most important ones as far as the sub is concerned. As I said before, my SB12 was perfect for me for 90% of my normal usage. But it's the 10% where it was lacking -- or when I stood outside of my normal usage pattern -- that prompted me to upgrade. It's a bit like uptime. Our internet link at work works well 99% of the time. But boy are we annoyed by that 1%!
Quote:
Example, a pair of Klipsch, RW-12D's coupled with a SVS, PC-13 Ultra or a Rythmik, FV15HP. In my mind's thinking, if doing this, one would have a very capable three subwoofer system that will have flat, mid-bass. But in coupling the less pair of subwoofers with a "MUCH MORE" capable subwoofer, when the crossover takes place (the two lesser subs drop out due to limited capability), coupled with the above <100 dB movie theater analysis, one will have and an "economical" solution to the dilemma of subwoofers cost too darn much!

I'm not so sure about your analysis. Assuming you don't need the output capabilites of the Ultra or FV15HP, then you're in only for the extension, or else you wouldn't bother with the high-end sub at all I guess. Well then, the PB-1000 has a profile that is quite close to the Ultra if you don't need the output. Why not using it instead? You'd save a boatload of money. Second, not sure what you mean by "when the crossover takes place". You'd have to somehow boost the low-end of the bigger sub only by 6 dB or more to get the low-end output to the level of the 3 combined subs where the two smaller ones have limited capability. This can be hard to achieve. If you can, well that's great. If you have to EQ the trio as a whole, then watch out: the 6-9 dB boost required below the roll-off of the lesser subs may damage them or induce distortion even at lower volumes. And third... well I suspect you'd like subs that can produce >100 dB rumbles once in a while.
Quote:
My bet, much of mixing and matching subwoofers revolves around cost as not everybody can afford three or four Funk Audion, 18.0C's and not many wives are going say, oh heck yeah, do it. tongue.gif

You're certainly right about this. The question remains: if you have a premium sub and lesser subs, should you or not get them to work together. Ultimately there's only one answer: try it and see if you like it and can manage to get interesting results at the levels you need/want. But I suspect that you will then have to do a trade-off between the benefits of a sub trio for smoothness and uniformity of middle and upper bass, and performance/output at very low frequencies (below the lesser subs' cut-off). And if you sacrifice very low frequency performance/output... why not using a third cheap sub instead?
Quote:
affording one "MUCH MORE" capable subwoofer is all many of us can afford.

Indeed. This is simply a rephrasing of the "one bigger sub or two smaller ones" dilemma, which assumes a fixed expense. The answer is obviously "two bigger ones" if you have the budget but then it's not much of a dilemma. Well it seems that "two smaller ones" is the consensus.
post #10146 of 15588
Quote:
Originally Posted by neutro View Post

Indeed. This is simply a rephrasing of the "one bigger sub or two smaller ones" dilemma, which assumes a fixed expense. The answer is obviously "two bigger ones" if you have the budget but then it's not much of a dilemma. Well it seems that "two smaller ones" is the consensus.

On my part, there no attempt at rephrasing going on. This is a purposeful decision or thought process if you will which is the blending of the three subs, when dialed in, "WILL" fill in the voids or nulls. The lesser subs, aside from the obvious economics of not tossing them on the ash heap, have two purposes, to aid the normal and natural nulls that "WILL" occur and in doing so, assure one of the much desired mid-bass punch. In the case of the "MUCH MORE" capable sub, when the two less capable subs drop out (crossover) then the "MUCH MORE" capable sub will continue as if it were one sub. Hence why the sub needs to be "MUCH MORE" capable so as the more capable sub picks up the <25Hz slack, one won't notice as the sub is out there by itself.

As to the issue regarding >90 to 95 dB, that's a measurement in a movie theater, not a measurement in a home so L/C/R has no bearing on the overall sound levels for the purpose of measured sound levels.. Some of the forum members are so busy pushing the issue (how loud can I make it go), they forget how they left rational behind a long time ago. On my part, due to my wife's sensitivity to "LOUD" sounds, the point of the research was to find out what the truth was regarding movie theater sound levels vs that of THX standards and what I found was, the two world's are not meeting in the way some here want others to believe they are.

-
Edited by BeeMan458 - 3/22/13 at 7:29pm
post #10147 of 15588
Just got the dual PB12-NSDs in my basement. There is some significant improvement but not as much as I expected after doing some demoing. Honestly I thought I would feel the bass in my chest a little more. Happy with the purchase but it wasn't a $1500 improvement. I may need to change the layout in the room or do some more testing. I found the subs were hitting the limiter fairly frequently.
post #10148 of 15588
Quote:
Originally Posted by JacobC1983 View Post

Just got the dual PB12-NSDs in my basement. There is some significant improvement but not as much as I expected after doing some demoing. Honestly I thought I would feel the bass in my chest a little more. Happy with the purchase but it wasn't a $1500 improvement. I may need to change the layout in the room or do some more testing. I found the subs were hitting the limiter fairly frequently.

Did you do the subwoofer crawl, to find the exact spots in your room, where the bass sounds the best?
What type of sub calibration did you use?
post #10149 of 15588
Quote:
Originally Posted by JacobC1983 View Post

Just got the dual PB12-NSDs in my basement. There is some significant improvement but not as much as I expected after doing some demoing. Honestly I thought I would feel the bass in my chest a little more. Happy with the purchase but it wasn't a $1500 improvement. I may need to change the layout in the room or do some more testing. I found the subs were hitting the limiter fairly frequently.

When you post regarding "testing," do you have measuring and auto EQ capability?
post #10150 of 15588
I did do the subwoofer crawl, and placed them close to the wall on each side of the TV, but I think they will do better if I place them closer to the middle and move the L + R speakers to the outside of the wall.

I used the audyssey setup on my Onkyo TX-NR1007

I do not have any measuring devices to measure decibals etc.

Panorama pictures to give you and idea of the room - the room isn't as big as it looks - it is wider than it is deep and the only entrance is at the back of the room which makes subwoofer placement almost impossible from that side of the room.



post #10151 of 15588
You need to identify the nulls at the primary listening position with an spl meter. You might be sitting in a significant null, especially when you're lighting up the limiters and still not feeling it in a small room.

Where is the main seating?

Keep the right sub near the front right corner and move the left sub to the left wall- near your left surround. Set both sub's gain to 12'clock and try again.
post #10152 of 15588
I will give that a shot - the main seating should be in at the end of the month.

Where would be a good place to buy a decent SPL meter
post #10153 of 15588
A digital SPL meter from RadioShack - model 33-2055 can get you started. You can usually find it on ebay for around $40. You can also go deeper down the rabbit hole by investing in a more accurate setup, such as REW and UMIK-1.
post #10154 of 15588
Quote:
Originally Posted by JacobC1983 View Post

Where would be a good place to buy a decent SPL meter

I recently pickup a sound meter from Amazon.

I have three sound meters, including the ever so popular, Radio Shack, digital sound meter. I find the one from Amazon linked above to be the best of the <$100.00 sound meters.

It's a rated Type 2 sound level meter that goes down to 30dB and is much more versatile then the less expensive Radio Shack, digital sound meter which is unrated for accuracy and one needs to use a correction table. I like good testing gear. tongue.gif

There are four grades of sound level meters. Lab grade being Type 0 and 1. Type 2 has a lower accuracy threshold and is for general certified survey purposes. The Type 3 is a general use that does not adhere to IEC (International Electromechanical Commission) standards The Radio Shack, digital sound meter is an unrated sound level meter.

FWIW, as to accuracy, I purchased a sound meter calibration device so I can check and calibrate the sound meters I do have.

-
Edited by BeeMan458 - 3/23/13 at 12:46pm
post #10155 of 15588
Just moved the two subs next to the TV stand and moved the L + R out - this helps the punch feeling I was expecting. For movies it is a very nice improvement over the previous Klipsch subs.

Will check out the radioshack digital SPL meter and see where that leads me.
post #10156 of 15588
Hey guys, I could really use some help! I just recently moved and had the unfortunate pleasure of setting all of my stuff up again. Anyway, my SVS PB12/plus is messed up now and I can't figure it out. When the power is on and rca cable is connected to the out I get this really low frequency hum. If I turn the gain up it get's really LOUD. I didn't change anything from how it was before but something is definitely wrong. My receiver also doesn't recognize the sub anymore. Something is wrong and I'm quite sure what to do. I was very carefull with it when moving and I have tried 3 different cables and it's the same with all of them. Anyone have any suggestions?
post #10157 of 15588
Quote:
Originally Posted by fletcher6490 View Post

Hey guys, I could really use some help! I just recently moved and had the unfortunate pleasure of setting all of my stuff up again. Anyway, my SVS PB12/plus is messed up now and I can't figure it out. When the power is on and rca cable is connected to the out I get this really low frequency hum. If I turn the gain up it get's really LOUD. I didn't change anything from how it was before but something is definitely wrong. My receiver also doesn't recognize the sub anymore. Something is wrong and I'm quite sure what to do. I was very carefull with it when moving and I have tried 3 different cables and it's the same with all of them. Anyone have any suggestions?



What receiver do you have? When you said "rca cable is connected to the out", do you mean "out" on the subwoofer outlet at the receiver and hooked at the LFE input at the subwoofer?

One more thing, do you have the PB12-Plus with the Bash or Sledge amp?
post #10158 of 15588
Quote:
Originally Posted by JacobC1983 View Post

Will check out the radioshack digital SPL meter and see where that leads me.

Please buy better. You'll thank yourself for doing so.

Side-by-side, when compared to the recommended, back lit, Type 2 version, the Radio Shack version, is quality vs junk with the Radio Shack version being junk in comparison.. It really is that much of a difference. Based on personal experience, unless you like junk over quality, I flat out cannot recommend the Radio Shack version over the one I recommended. The step down in quality is not worth the few extra dollars in savings.

This is a link to the other sound meter I have. It's more expensive and I can't recommend it either.

If you just have to buy cheaper (Radio Shack), I completely and totally support your buying decision.

-
Edited by BeeMan458 - 3/24/13 at 1:25pm
post #10159 of 15588
Quote:
Originally Posted by cr136124 View Post

What receiver do you have? When you said "rca cable is connected to the out", do you mean "out" on the subwoofer outlet at the receiver and hooked at the LFE input at the subwoofer?

One more thing, do you have the PB12-Plus with the Bash or Sledge amp?

I have a Pioneer elite SC-25. I have the PB12 with the bash amp. Yes, out on the sub to the LFE to the sub lfe input. I have it exactly how I had it before I moved because I actually didn't unplug the cables on the sub. I've tried different power cords and different rca cables and it's the same result. Something is definitely wrong, especially since my receiver doesn't see the sub when I run speaker tones.
post #10160 of 15588
Quote:
Originally Posted by BeeMan458 View Post

This is a purposeful decision or thought process if you will which is the blending of the three subs, when dialed in, "WILL" fill in the voids or nulls.

I agree with that part: the three subs will probably sound better in their common frequency range.
Quote:
In the case of the "MUCH MORE" capable sub, when the two less capable subs drop out (crossover) then the "MUCH MORE" capable sub will continue as if it were one sub. Hence why the sub needs to be "MUCH MORE" capable so as the more capable sub picks up the <25Hz slack, one won't notice as the sub is out there by itself.

The problem with that is how you intend to EQ the subs to get that result. Do you plan on EQing the bigger sub independantly of the two others? If so, how exactly? If you EQ the three subs as a whole, then you'll run on the problems I mentioned in my earlier post. In any way, I'm quite interested to know how you achieve this.

As for the loudness -- this is basically a matter of personal preference. On evenings when the kid is asleep, I often feel that -22 dB from reference is loud-ish. When I'm alone at home on a rainy afternoon and watching a movie for myself, -5 dB is loud-ish biggrin.gif Also, human hearing is quite flexible, so that you get accustomed to the loudness after a while. I'm not saying this is healthy, but one can adapt to listening at reference level. On the other hand, it's the best way to get the whole dynamic range of the movie (e.g. hearing to the very soft parts clearly) without using dynamic range compression processing such as DSX.

Quote:
Originally Posted by JacobC1983 View Post

Just got the dual PB12-NSDs in my basement. There is some significant improvement but not as much as I expected after doing some demoing. Honestly I thought I would feel the bass in my chest a little more. Happy with the purchase but it wasn't a $1500 improvement

I'm happy you finally got the PB12s to sound better by relocating them. This shows how location is of tremendous importance even with duals. Also note that EQing the sub can drastically change how they sound, and that chest thump is actually an "upper" bass phenomena that you get at very high listening volumes.

Quote:
Originally Posted by BeeMan458 View Post

I flat out cannot recommend the Radio Shack version over the one I recommended.
(...)
This is a link to the other sound meter I have. It's more expensive and I can't recommend it either.

So... which one do you recommend exactly then? The problem I had while looking for SPL meters, and the reason why I chose the RS one, is that I wanted to have an SPL meter with known calibration files in order to use it in REW as a mic. Maybe I should just buy a better SPL meter, and a better, separate mic, but at this point, I think my setup works "well enough" without investing $200 in new measurement gear. However, I'm open to have that conclusion challenged biggrin.gif

Quote:
Originally Posted by fletcher6490 View Post

Something is definitely wrong, especially since my receiver doesn't see the sub when I run speaker tones.

It doesn't look good... Did you contact SVS? They might provide good advice!
post #10161 of 15588
Quote:
Originally Posted by fletcher6490 View Post

I have a Pioneer elite SC-25. I have the PB12 with the bash amp. Yes, out on the sub to the LFE to the sub lfe input. I have it exactly how I had it before I moved because I actually didn't unplug the cables on the sub. I've tried different power cords and different rca cables and it's the same result. Something is definitely wrong, especially since my receiver doesn't see the sub when I run speaker tones.

Its always best to double/triple check the easy things, as we often forget about them. The RCA from the receiver should be hooked up to the line level (RCA) input on the sub. The RCA cable on the sub needs to be connected to the "Pre-out" section and not the "Multi Ch In" grouping of RCA terminals. The Pre-outs are the upper of the two groupings, both of which have a terminal labeled for the sub. The pre-out sub section is the one with the white block around it. If you are looking at the rear panel head on, it is the second row of RCA audio terminals, third from the right, and is red.



Here's the sub amp. In the top right corner are the line level inputs and outputs. Make sure the cable is put into one of the inputs, which are the left set of the four RCA plugs. It doesn't matter if the cable is going into the red or white inputs, just so long as it is an input an not the output. You may also want to verify that you are not having an RCA terminal issue by simply moving the RCA cable from the red to the white terminal (or vice versa).




The AVR should have its bass management settings reviewed to make sure that the sub is selected (if no sub is showing in the AVR's bass management settings, it won't send any signals to the sub), the AVR's manual goes over where and how to check this. Here's a pdf of the SC-25 manual. Sometimes if a signal is stereo and the speakers are set to large, then a signal will not be sent to the sub, but you should still be able to get the AVR's internal test tones to generate a sound as long as the AVR knows that a sub is in the system. Its been awhile since I've played with a Pioneer AVR, so I am going to have to go on trust that there are no extra/odd steps in the set up. Others who currently run Pio's may be of more assistance here.

If you are still not getting any signals you can start the process of elimination. Try hooking up a source directly to the sub to make sure the preamp section on the sub is receiving signals. This can be an RCA from a multichannel out on a DVD/BR player, or even just a line from a L/R on a CD player (keep the subs gain control low and only test for a very short period of time and you should be fine with a full bandwidth signal as a test).

This should at least let you verify that the sub is hooked up correctly, that the sub is selected, and if tested with a separate source, that the sub is/is not receiving signals.

As for the humming sound, it may be a ground loop 60hz hum. Many times these pop up when proper grounding hasn't been done, and in many cases comes from cable/sat boxes. Does the sub hum when no cables other than the power are connected to it? If it doesn't then try disconnecting your cable/sat box from the AVR and reconnect the RCA cable from the AVR to the sub. If the hum doesn't appear while the cable/sat box is disconnected, you have found your culprit. Sometimes cable companies will fix the issue, sometimes they won't. You can look at different solutions for the hum such as an isolator or plugging the subwoofer into a different power outlet on a different circuit to see if that helps reduce/eliminate it.

Hopefully this at least gets the process going in getting the issues resolved for you.

Edit: Fixed broken link
Edited by Snowmanick - 3/24/13 at 4:52pm
post #10162 of 15588
Quote:
Originally Posted by Snowmanick View Post

Its always best to double/triple check the easy things, as we often forget about them. The RCA from the receiver should be hooked up to the line level (RCA) input on the sub. The RCA cable on the sub needs to be connected to the "Pre-out" section and not the "Multi Ch In" grouping of RCA terminals. The Pre-outs are the upper of the two groupings, both of which have a terminal labeled for the sub. The pre-out sub section is the one with the white block around it. If you are looking at the rear panel head on, it is the second row of RCA audio terminals, third from the right, and is red.



In the top right corner are the line level inputs and outputs. Make sure the cable is put into one of the inputs, which are the left set of the four RCA plugs. It doesn't matter if the cable is going into the red or white inputs, just so long as it is an input an not the output. You may also want to verify that you are not having an RCA terminal issue by simply moving the RCA cable from the red to the white terminal (or vice versa).




The AVR should have its bass management settings reviewed to make sure that the sub is selected (if no sub is showing in the AVR's bass management settings, it won't send any signals to the sub), the AVR's manual goes over where and how to check this. Here's a pdf of the SC-25 manual. Sometimes if a signal is stereo and the speakers are set to large, then a signal will not be sent to the sub, but you should still be able to get the AVR's internal test tones to generate a sound as long as the AVR knows that a sub is in the system. Its been awhile since I've played with a Pioneer AVR, so I am going to have to go on trust that there are no extra/odd steps in the set up. Others who currently run Pio's may be of more assistance here..

If you are still not getting any signals you can start the process of elimination. Try hooking up a source directly to the sub to make sure the preamp section on the sub is receiving signals. This can be an RCA from a multichannel out on a DVD/BR player, or even just a line from a L/R on a CD player (keep the subs gain control low and only test for a very short period of time and you should be fine with a full bandwidth signal as a test).

This should at least let you verify that the sub is hooked up correctly, that the sub is selected, and if tested with a separate source, that the sub is/is not receiving signals.

As for the humming sound, it may be a ground signal 60hz hum. Many times these pop up when proper grounding hasn't been done, and in many cases comes from cable/sat boxes. Does the sub hum when no cables other than the power are connected to it? If it doesn't then try disconnecting your cable/sat box from the AVR and reconnect the RCA cable from the AVR to the sub. If the hum doesn't appear while the cable/sat box is disconnected, you have found your culprit. Sometimes cable companies will fix the issue, sometimes they won't You can look at different solutions for the hum such as[URL=http://ground loop isolator] isolators [/URL] or plugging the subwoofer into a different power outlet on a different circuit to see if that helps reduce/eliminate it.

Hopefully this at least gets the process going in getting the issues resolved for you.

Great post! Thank you. I tried to only plug in the sub with everything else unplugged and there is still the hum. I honestly don't know what's wrong and I'm starting to worry that something is wrong. I'll contact SVS tomorrow but I really do appreciate your very informative response.
post #10163 of 15588
Quote:
Originally Posted by neutro View Post

The problem with that is how you intend to EQ the subs to get that result. Do you plan on EQing the bigger sub independantly of the two others? If so, how exactly? If you EQ the three subs as a whole, then you'll run on the problems I mentioned in my earlier post. In any way, I'm quite interested to know how you achieve this.

In my opinion, the problems are self-correcting. The reason being, in my way of thinking, all problems have been accounted for and there are no problems to be corrected for and everything will EQ seamlessly. And if I'm wrong, I'll have a "MUCH MORE" capable subwoofer as a prize. tongue.gif

Quote:
So... which one do you recommend exactly then? The problem I had while looking for SPL meters, and the reason why I chose the RS one, is that I wanted to have an SPL meter with known calibration files in order to use it in REW as a mic. Maybe I should just buy a better SPL meter, and a better, separate mic, but at this point, I think my setup works "well enough" without investing $200 in new measurement gear. However, I'm open to have that conclusion challenged biggrin.gif

The recommended sound meter is the first linked sound meter.

The meter being a better (Type 2) meter, meets necessary legal/industry consistency standards and is not in need of a correction table. Also, I purchased an EMM-6, dedicated recording mic to be used with REW. The mic comes with a downloadable calibration file which can easily be integrated with REW. If using a computer within 15" of the microphone placemen, if one wishes, they can purchase a USB model and save some money by not having to buy additional patch cords or a phantom power supply.

FWIW, I have and have used a Radio Shack meter for the last fifteen years. I decided I wanted better than a Radio Shack sound meter because it's a bit too limited for my personal tastes in measuring gear. I didn't like that it only went down to 60dB. I didn't like that it's use was dependent on a conversion table and I didn't have a method to check it's accuracy so by nature, on several levels, not meaning to read as if being overly dramatic, these were more limitations then I could live with. So I took the online time to read up on sound meters, and ordered a few sound meters and a sound meter calibrator.

One sound meter I returned because it became defective, One works but is limited to >40dB, who's power button is a bit wonky and the one I linked to above, has been nothing but superior to the other three sound meters it was compared against, including the Radio Shack, digital sound meter.

-
Edited by BeeMan458 - 3/24/13 at 6:10pm
post #10164 of 15588
Quote:
Originally Posted by BeeMan458 View Post

What is missing is the fact that despite a movie sound track being mixed to THX standards, only 0.01% of movie volume in a theater is +90 to 95 dB(A).
"Cinemas - do they pose a risk to hearing?"
-

The problem with that study is it has no relevance to subwoofer output. All the measurements are A weighting so basically everything below about 200hz was filtered out. A weighting is 20db down at 100hz and 50db down at 20hz. So any subwoofer content is left out of those measurements. Also don't forget most movie theaters only have output down to about 30hz, so any content below that will not be reproduced in the theater at all. Just look at a waterfall capture of any of the bass demo movies. There is plenty of content in the subwoofer range encoded at -15dBFS which is 100dB. There is no easy way to figure out the percentage of a movie that has "loud" content in the subwoofer range, but some movies have an average of 80-85db at specific frequencies over the entire movie. I think you are vastly underestimating the level of subwoofer content in a lot of movies.
Quote:
Originally Posted by BeeMan458 View Post

The recommended sound meter is the first linked sound meter.

The meter being a better (Type 2) meter, meets necessary legal/industry consistency standards and is not in need of a correction table. Also, I purchased an EMM-6, dedicated recording mic to be used with REW. The mic comes with a downloadable calibration file which can easily be integrated with REW. If using a computer within 15" of the microphone placemen, if one wishes, they can purchase a USB model and save some money by not having to buy additional patch cords or a phantom power supply.

FWIW, I have and have used a Radio Shack meter for the last fifteen years. I decided I wanted better than a Radio Shack sound meter because it's a bit too limited for my personal tastes in measuring gear. I didn't like that it only went down to 60dB. I didn't like that it's use was dependent on a conversion table and I didn't have a method to check it's accuracy so by nature, on several levels, not meaning to read as if being overly dramatic, these were more limitations then I could live with. So I took the online time to read up on sound meters, and ordered a few sound meters and a sound meter calibrator.

One sound meter I returned because it became defective, One works but is limited to >40dB, who's power button is a bit wonky and the one I linked to above, has been nothing but superior to the other three sound meters it was compared against, including the Radio Shack, digital sound meter.

-

When taking "accurate" measurements, you can look at two things: the frequency response (levels of frequencies relative to each other) and absolute SPL levels.

For frequency response measurements, multiple people have shown that the Radio Shack digital meter is relatively accurate from about 15-200hz if used with C-weighting compensation. Of course if you want to measure lower than that or want reassurance in the accuracy, an individually calibrated mic from CSL is better. All C-Weighted SPL meters, even type 1 and 2, will need compensation when doing frequency response measurements. Getting an IEC or ANSI rated meter will help ensure some level of accuracy, but not much at the lowest frequencies. ANSI Type 2 meters are rated +-2db from 80-40hz, +-3db from 31.5-20hz and +5, - infinity from 16hz and below.

For SPL measurements, IMO, extreme accuracy is not very important. Frequency response of the sub is much more important than accurate SPL levels. There are too many other factors that can change SPL readings (temperature, humidity, noise floor,etc.) for me to worry about getting a very accurate meter. As long as the measurements are repeatable, I'm not going to worry about being a couple dB off.

In the end, if you already have a Radio Shack meter, there are many useful measurements that can be taken. If you want to measure below 20hz or want a higher level of accuracy and confidence, get a calibrated mic from CSL. If you want to measure outside the SPL range of the Radio Shack meter or want a higher level of confidence in the SPL reading, get an ANSI or IEC rated meter.

-Mike
post #10165 of 15588
Quote:
Originally Posted by ironhead1230 View Post

The problem with that study is it has no relevance to subwoofer output. All the measurements are A weighting so basically everything below about 200hz was filtered out.

Of course it's relevant in that we listen to a movie sound track in full spectrum (A weighted), not just subwoofer output and Home Theater output is an amalgam of a full set of speakers, not just a subwoofer or four. The measurements were full spectrum, movie sound track output so correctly, all frequencies were considered equally and correctly, "A" weighting was used.

As to the sound meter comments, I stated that the sound level meter was a calibrated Type 2 sound meter which meets international standards and is more than can be said about a Radio Shack meter. It reads as if the Radio Shack meter is the only sound meter one is allowed to recommend.

Quote:
All C-Weighted SPL meters, even type 1 and 2, will need compensation when doing frequency response measurements.

In all I've read, nowhere did I read your above, stating lab grade (Type 0 and Type 1) or general survey Type 2 sound meters are in need of compensation.

Quote:
If you want to measure outside the SPL range of the Radio Shack meter or want a higher level of confidence in the SPL reading, get an ANSI or IEC rated meter.

Which is what I did and what I recommend. confused.gif

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Edited by BeeMan458 - 3/25/13 at 7:40am
post #10166 of 15588
Quote:
Originally Posted by BeeMan458 View Post

Of course it's relevant in that we listen to a movie sound track in full spectrum (A weighted), not just subwoofer output and Home Theater output is an amalgam of a full set of speakers, not just a subwoofer or four.

A-weighed is *not* full spectrum. What Ironhead said can be observed by wiping out your SPL meter during a movie. Even when the mains play dialog at 80 dB SPL, you'll see SPL values *much* above that when the LFE are playing. The thing is, loud LFEs are not perceived at all like loud mids or highs.
post #10167 of 15588
Quote:
Originally Posted by neutro View Post

A-weighed is *not* full spectrum.
+1. 'A' weighting should never be used in any audio application. It's only properly employed in industrial and environmental noise level measurement applications.
post #10168 of 15588
Quote:
Originally Posted by neutro View Post

A-weighed is *not* full spectrum. What Ironhead said can be observed by wiping out your SPL meter during a movie. Even when the mains play dialog at 80 dB SPL, you'll see SPL values *much* above that when the LFE are playing. The thing is, loud LFEs are not perceived at all like loud mids or highs.

You have a link that is a study based on a matrix of twenty-five movies?

We don't go to movie theaters anymore so I won't be doing any personal studies to corroborate or disprove your above but personal "A" weighted, "C" weighted measurements at home don't agree with your above.

What I don't get, why all the bro-ha-ha for someone recommending anything but a Radio Shack sound meter? Are folks so myopic they can only see/recommend Radio Shack sound meters?

.....confused.gif

-
post #10169 of 15588
im thinking about grabbing an Antimode for 280 shipped...any thoughts on it?
post #10170 of 15588
Quote:
Originally Posted by BeeMan458 View Post

You have a link that is a study based on a matrix of twenty-five movies?

We don't go to movie theaters anymore so I won't be doing any personal studies to corroborate or disprove your above but personal "A" weighted, "C" weighted measurements at home don't agree with your above.

What I don't get, why all the bro-ha-ha for someone recommending anything but a Radio Shack sound meter? Are folks so myopic they can only see/recommend Radio Shack sound meters?

.....confused.gif

-

SVS recommends a Radio Shack analog meter and measuring c-weighted. That's what I'm going to get.
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