Questions about duals

[NorCalRP]

The PB-1000 would not terrible to mate with a VTF-3 mk4 because SVS tends to place strict limits on the amount of distortion they can produce. The SVS sub will not be able to produce that much bad noise. The only problem is mismatched tuning points below the tuning frequency of the highest tuned sub. Thankfully the VTF-3 with both ports open in EQ2 mode will have a very similar response and tuning point to the PB-1000. I have the predecessor to the VTF-3 mk4, I have some mk3s, and I adore the design, by the way. It is a large sub though, so make sure you understand how big it is before you pull the trigger.

I'm going to pick it up Thursday. I sure am glad for your insight. I do want to make sure on the configuration. Your advice is for Max output, rather than Max extension. The stated response of the SVS dips to 19hz, where as the low end on the HSU is 18hz. Is the setting you suggest going to give me the most similar response curves?

Also, when I originally set the system up I used the manual setup. I then ran Audyssey, and oh boy what a difference. I'm planning on setting all the sub controls to flat/neutral (?), and then run Audyssey again. Do you think this is the way to go?

 

[shadyJ]

I'm going to pick it up Thursday. I sure am glad for your insight. I do want to make sure on the configuration. Your advice is for Max output, rather than Max extension. The stated response of the SVS dips to 19hz, where as the low end on the HSU is 18hz. Is the setting you suggest going to give me the most similar response curves?

Also, when I originally set the system up I used the manual setup. I then ran Audyssey, and oh boy what a difference. I'm planning on setting all the sub controls to flat/neutral (?), and then run Audyssey again. Do you think this is the way to go?

Don't worry about the stated responses. What we are more interested in is the shape of the curves. Let's look at the curve for the PB-1000:

Now lets look at the curves for the VTF-3 mk4:
2 port mode:

1 port mode:

So we can see that the VTF-3 has its closest response to the PB-1000 with 2 ports open. You can run the VTF-3 with 1 port open alongside the PB-1000, but the PB-1000 might subtract some of its output below 20 Hz since it will be running in opposite phase, although it probably won't reduce it by too much. But they will play together more nicely if you run the VTF-3 with 2 ports open.

One thing to be sure of is that the subs are in phase! You can do this by ear but it helps to have an SPL meter. Use a test tone generator like this one and run test tones in frequencies below the crossover frequency with both subs going. Try to get the subs level-matched for this. When running the tones, flip the phase switch on the Hsu sub and listen for a drop or rise in loudness in the overall sound. Keep the phase setting that gives you the most output. its better to do this with an SPL meter at your listening position, but it still should be audible.

 

[NorCalRP]

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Don't worry about the stated responses. What we are more interested in is the shape of the curves. Let's look at the curve for the PB-1000:

Now lets look at the curves for the VTF-3 mk4:
2 port mode:

1 port mode:

So we can see that the VTF-3 has its closest response to the PB-1000 with 2 ports open. You can run the VTF-3 with 1 port open alongside the PB-1000, but the PB-1000 might subtract some of its output below 20 Hz since it will be running in opposite phase, although it probably won't reduce it by too much. But they will play together more nicely if you run the VTF-3 with 2 ports open.

One thing to be sure of is that the subs are in phase! You can do this by ear but it helps to have an SPL meter. Use a test tone generator like this one and run test tones in frequencies below the crossover frequency with both subs going. Try to get the subs level-matched for this. When running the tones, flip the phase switch on the Hsu sub and listen for a drop or rise in loudness in the overall sound. Keep the phase setting that gives you the most output. its better to do this with an SPL meter at your listening position, but it still should be audible.

Hell yeah, man! Thanks for the detailed reply. One last question and I should be good to start tweaking. My listening position is close to where the new sub is going to go. I would like to have the driver facing me which would have the ports facing the back corner. Would it be better to have the ports facing forward and therefore have the driver facing the wall? Or would it just be better to try it both ways and see what gets me the best output?

 

[shadyJ]

Regarding ports facing you or driver facing you, you might as well try it both ways and see what you like the most. I suspect you will enjoy the driver facing you, if you can discern a difference. The tactile "chest-thump' bass frequencies are going to be generated more by the driver than ports.

One more thing, the VTF-3 mk4 is considerably more powerful than the PB-1000. Don't beat the PB-1000 to death by trying to make it keep up with the VTF-3 mk4. I would use the PB-1000 to supplement any room-based nulls left in the response from the VTF-3 mk4 rather than trying to make then have equal duty. Make sure the VTF-3 mk4 is your primary sub and just use the PB-1000 to enhance the response after you get the VTF-3 set up.

Also, be ready for the size of the VTF-3 mk4. it is not a small subwoofer.

 

[NorCalRP]

Regarding ports facing you or driver facing you, you might as well try it both ways and see what you like the most. I suspect you will enjoy the driver facing you, if you can discern a difference. The tactile "chest-thump' bass frequencies are going to be generated more by the driver than ports.

One more thing, the VTF-3 mk4 is considerably more powerful than the PB-1000. Don't beat the PB-1000 to death by trying to make it keep up with the VTF-3 mk4. I would use the PB-1000 to supplement any room-based nulls left in the response from the VTF-3 mk4 rather than trying to make then have equal duty. Make sure the VTF-3 mk4 is your primary sub and just use the PB-1000 to enhance the response after you get the VTF-3 set up.

Also, be ready for the size of the VTF-3 mk4. it is not a small subwoofer.

It's gloriously large. I brought it in the house after the Misses went to bed. I told her I bought it and that it's big. I'm guessing her reaction will be as comical to me as it is exasperating to her

 

[NorCalRP]

Shady,

On another thread I mentioned I picked this sub up to even out response, and you replied that placing it in the opposite corner might actually have an adverse effect. You used the phrase "smooth out" rather than "even out". I'm wondering if I maybe used the wrong term (self-proclaimed noob here). What I'm truly wishing for is the bass to feel and sound the same in as many spots as possible. Putting it in the opposite corner is pretty much my only viable option right now. Your reply freaked me out, albeit very slightly. Any further thoughts? I don't have a dedicated spl meter, just an app on my phone- Google Pixel 2 XL

 

[shadyJ]

The opposite corner placement might be fine, but its impossible to say without measurements. Until you get a way to measure the subs, i would say just put them where the overall sound is best to your ears.

 

[NorCalRP]

The opposite corner placement might be fine, but its impossible to say without measurements. Until you get a way to measure the subs, i would say just put them where the overall sound is best to your ears.

I put the HSU where I had the SVS, and put the SVS pretty close to me seating position. I'm waiting on a cable to hook up my SVS then will be able to use an SPL meter to check phase and placement. I figure it'll be easier move the smaller SVS if needed. I really see what you meant about the HSU being more powerful. I'm definitely going to have to do some work to cut down in vibrations!

 

[snakeeyes]

I put the HSU where I had the SVS, and put the SVS pretty close to me seating position. I'm waiting on a cable to hook up my SVS then will be able to use an SPL meter to check phase and placement. I figure it'll be easier move the smaller SVS if needed. I really see what you meant about the HSU being more powerful. I'm definitely going to have to do some work to cut down in vibrations!

Did you try out 1 port mode yet? You might want to see the true power of that HSU before opening both ports to play nice with the SVS 10in

 

[NorCalRP]

Did you try out 1 port mode yet? You might want to see the true power of that HSU before opening both ports to play nice with the SVS 10in

Shady mentioned going the 2 port mode to get the most similar response curves. Also mentioned was using the SVS, not equally and therefore pushing it, but rather to supplement, thereby decreasing nodes and not pushing it too hard. My idea of addressing this is to run Audyssey with both subs set the same way control wise, then decrease the volume on my svs

 

[snakeeyes]

Shady mentioned going the 2 port mode to get the most similar response curves. Also mentioned was using the SVS, not equally and therefore pushing it, but rather to supplement, thereby decreasing nodes and not pushing it too hard. My idea of addressing this is to run Audyssey with both subs set the same way control wise, then decrease the volume on my svs

Oh I just meant playing with the hsu while you were without the svs sub cable. Definitely follow shady’s lead for the sub integration.

 

[NorCalRP]

Oh I just meant playing with the hsu while you were without the svs sub cable. Definitely follow shady’s lead for the sub integration.

Cable's in the house!!!