SVS PB13-Ultra Subwoofer Review

[fuzz092888]

Alright, so this will be try number 2 to post this.

I just took delivery recently of an SVS PB13Ultra. It's a beast. A gorilla in piano black. I installed it and didn't tweak the settings initially and got several texts from my wife upstairs on the other side of the house that our chimney was rattling and to knock it off.

I use my theatre mostly for movies. I had a few guys over the other night who got me setup so I could do 2 channel if I wanted... I don't think it's for me. I've watched a few movies on it and I have been thoroughly impressed with the stately authority that is projected from this beast. I have it paired with a small Linn sub. While the Linn has a very large range, it doesn't have the lungs to compete with the SVS. But then, comparing the amplifiers, it's really got a fart's chance in a hurricane to keep up.

So movies...

Avengers - my setup really picked out the mixing problems. The SVS loved all the explosions. The music was very low in the mix. The voices were pretty intelligible.

Pacific Rim - mixed beautifully and who doesn't love giant monsters fighting giant robots? The SVS mowed through everything Mr. Del Toro was able to dish up.

The Last Stand - Honestly this had the greatest sounding shotgun blasts of any movie I've seen recently, even in theatre. Really enjoyed it.

GI Joe: Retalliation - Terrible movie, very well mixed sound. The SVS didn't care. It may as well have been playing the Smurfs. At this point, I really had the SVS dialled in and it was less a gorilla and more proud, and dependable workhorse, blending into the background when necessary and rising to the forefront when called. It's really an amazing sub.

I highly recommend it. Yes, I would like another SVS sub. Will I get one? I don't know. There are a lot of other purchases that I would like to get first before that and they're all really expensive.

Subwoofers are so much fun. I love reading about people discovering how much fun a really good subwoofer can be

 

[dmusoke]

Which mode has the least distortion?

Gene:

I'm find something confusing between the Ground Plane results and the 105dB THD plots. In the former, the 20Hz mode has much less distortion than the 15Hz mode, yet the 105dB THD plots show the opposite. The 15Hz mode has less distortion than the 20Hz mode especially below 20hz. How can this be?

Thanks,
David

 

[fuzz092888]

Gene:

I'm find something confusing between the Ground Plane results and the 105dB THD plots. In the former, the 20Hz mode has much less distortion than the 15Hz mode, yet the 105dB THD plots show the opposite. The 15Hz mode has less distortion than the 20Hz mode especially below 20hz. How can this be?

Thanks,
David

The 105db graph is for a sweep, which is to say there is a continuous tone that plays from X hz to X hz while a microphone graphs hundreds or thousands of data points as the tone plays in order to create the distortion graph. Meanwhile, the CEA testing methodology was created in order to better simulate real world content and what a subwoofer could do under those conditions. The CEA testing uses specific frequencies and it's not a tone, but more of a chirp that gets played at the respective frequencies. The microphone then records magnitude (SPL) and distortion.

As to why they differ, you have to keep in mind that they're testing in two very different ways (continuous tone vs sweep for one) and probably more importantly, one is testing subwoofer performance at a given SPL while the other is testing for maximum output at certain frequencies while staying under a certain level of distortion. Basically the graphs aren't A/B comparable because they aren't testing for the same things.

Hope that makes some sense.

 

[dmusoke]

The 105db graph is for a sweep, which is to say there is a continuous tone that plays from X hz to X hz while a microphone graphs hundreds or thousands of data points as the tone plays in order to create the distortion graph. Meanwhile, the CEA testing methodology was created in order to better simulate real world content and what a subwoofer could do under those conditions. The CEA testing uses specific frequencies and it's not a tone, but more of a chirp that gets played at the respective frequencies. The microphone then records magnitude (SPL) and distortion.

As to why they differ, you have to keep in mind that they're testing in two very different ways (continuous tone vs sweep for one) and probably more importantly, one is testing subwoofer performance at a given SPL while the other is testing for maximum output at certain frequencies while staying under a certain level of distortion. Basically the graphs aren't A/B comparable because they aren't testing for the same things.

Hope that makes some sense.

Thanks for the explanation Fuzz and i have to say that it was fuzzy...

I understand one method uses a swept tone from 10Hz to 125Hz to measure the sub's distortion at a 105dB level. The CEA method uses discrete frequencies for its method but the results should still be similar to the swept tone method. Since THD measurements are measured one frequency at a time, swept tone or discrete, the results should be similar. Like i said before, the swept tone has the 15Hz mode with the least distortion whereas the CEA2010 has the 20Hz mode with the least distortion. My argument is that both methods should present the same message.

Could it be that the swept tone graph was mis-labeled?

 

[fuzz092888]

Looking more closely at the graph, you'll see that the 15hz mode doesn't offer lower distortion than the 20hz mode, except below the tuning point. The swept tone graph isn't mislabeled.

This graph shows the same thing except with a 110db tone. The distortion of the 15hz mode starts to raise higher than the 20hz mode at around 55hz and continues to rise higher than the 20hz mode until the 20hz mode gets close to the tuning frequency. Below the tuning frequency, the 15hz mode has lower distortion, as it should, since it is tuned lower. The tradeoff for that extra extension is rising distortion starting at 50-60hz. The CEA results show the same thing.

Data-Bass

 

[dmusoke]

Looking more closely at the graph, you'll see that the 15hz mode doesn't offer lower distortion than the 20hz mode, except below the tuning point. The swept tone graph isn't mislabeled.

This graph shows the same thing except with a 110db tone. The distortion of the 15hz mode starts to raise higher than the 20hz mode at around 55hz and continues to rise higher than the 20hz mode until the 20hz mode gets close to the tuning frequency. Below the tuning frequency, the 15hz mode has lower distortion, as it should, since it is tuned lower. The tradeoff for that extra extension is rising distortion starting at 50-60hz. The CEA results show the same thing.

Data-Bass

I see what you are saying now with the graphs. You're observations are correct in this regard. Is distortion of 10% or greater at 20Hz or lower audible? If so, then I'm tempted to think that the 15Hz mode is best overall based on the graphs iwth THD less than 5% up to the tuning frequency?

 

[dmusoke]

I hope the new SB13 gets reviewed soon...

 

[fuzz092888]

I see what you are saying now with the graphs. You're observations are correct in this regard. Is distortion of 10% or greater at 20Hz or lower audible? If so, then I'm tempted to think that the 15Hz mode is best overall based on the graphs iwth THD less than 5% up to the tuning frequency?

Based on the CEA results, some of the other graphs, and my own personal preferences/experiences I would go with the 20hz tune, at least based on the raw numbers. The 20hz tune is going to have lower distortion overall, in room gain will boost the extension you get slightly and you'll get more output/have more headroom over the 15hz tune.

As to the distortion question, at moderate volumes with distortion far less than 5%, I doubt you'd notice a difference between either mode. At higher volumes, depending on the content you may notice that extra bit of extension, you may not. Distortion may begin to come into play, but I doubt it. Both tunes will, by my estimation still sound similar. At full on reference playback with a demanding soundtrack is where you'd probably notice the biggest difference. Since 20hz and below is more felt than heard, I'd still probably go for 20hz tune since I'm not really seeing enough meaningful output over the 20hz tune to risk rising distortion while also sacrificing output and increasing thermal compression. IMHO of course and I'll throw in the disclaimer that I've never actually heard this particular sub so my opinion might be different if I did get to audition it. Then again maybe not as well.

 

[dmusoke]

Based on the CEA results, some of the other graphs, and my own personal preferences/experiences I would go with the 20hz tune, at least based on the raw numbers. The 20hz tune is going to have lower distortion overall, in room gain will boost the extension you get slightly and you'll get more output/have more headroom over the 15hz tune.

As to the distortion question, at moderate volumes with distortion far less than 5%, I doubt you'd notice a difference between either mode. At higher volumes, depending on the content you may notice that extra bit of extension, you may not. Distortion may begin to come into play, but I doubt it. Both tunes will, by my estimation still sound similar. At full on reference playback with a demanding soundtrack is where you'd probably notice the biggest difference. Since 20hz and below is more felt than heard, I'd still probably go for 20hz tune since I'm not really seeing enough meaningful output over the 20hz tune to risk rising distortion while also sacrificing output and increasing thermal compression. IMHO of course and I'll throw in the disclaimer that I've never actually heard this particular sub so my opinion might be different if I did get to audition it. Then again maybe not as well.

I agree... Thank you so much Fuzz for the help you've provided explaining to me the details i was confused about .