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Next on the upgrade list: dual near-field subs.

post #1 of 89
Thread Starter 
I just finished bought eD cinema 6" bookshelf speakers for rears, so now I'm all set with 5 eD speakers.

Next up, figure out my sub situation.

I have 2 ported Captivators in the front corners (16.5 feet away) and movies sound awesome in this configuration. However, music is just really good. I do mean that, music is very satisfying with the subs up front especially after Luke Kamp eq'd my subs.

However, when I place the Captivators on the side walls directly flanking me so that each driver is around 6.5 feet from me music is the best I've experienced in my room - it gives me that nice tactile feel and punch even at lower volumes. Unfortunately in that same configuration movies are terrible so I've decided to go with the subs up front. Plus they make good speaker stands for my eD speakers.

Now I need to figure out what subs to get for near-field. I have a limited understanding of how subs interact with each other but let me give this a shot:

If I have 4 subs, 2 ported and 2 sealed, and the sealed subs dig deeper than the ported, then around the tuning frequency of the ported subs and a little bit below that, the bass will be out of phase since the ported sub is now playing out of phase (sound coming from back of driver/ports instead from the front of the driver near the tuning point of the sub) and will cancel out the sound from the sealed sub.

If I have 4 subs, all ported, and 2 of them don't play as deep then there will be a big cancellation around the tuning frequency (same reason as mentioned above) of the lesser subs right?


So, what about having 2 ported subs and 2 sealed subs and HPF the sealed subs to around 30 hz? Would that still cause the null/cancellation/phase/whatever issues that arise from having multiple subs?

Of course I could just turn off the Caps for music and turn off the other subs for movies but if there is a way to combine them I'd like to try it.

So, am I even close to understanding any of this? Luke if you are reading this I apologize if I butchered what you told me...

So, I guess my question is would it be better to go sealed or ported with the 2 new near-field subs?

Also if you think there is no magic to near-field sub placement and I must be screwing something up, feel free to let me know that too.
post #2 of 89
Quote:
Originally Posted by carp View Post

If I have 4 subs, 2 ported and 2 sealed, and the sealed subs dig deeper than the ported, then around the tuning frequency of the ported subs and a little bit below that, the bass will be out of phase since the ported sub is now playing out of phase (sound coming from back of driver/ports instead from the front of the driver near the tuning point of the sub) and will cancel out the sound from the sealed sub.

If that were the case, wouldn't the ported subs cancel with themselves already (sound from port cancelling its own direct output)?

I would have thought intuitively that cancellation would be due to distance differences - time alignment - and if you can independently set delay for the front and side subs, you can mitigate that?

Speculating here...
post #3 of 89
What about a couple midbass modules from HSU for the music? From my understanding you could have a hell of a time trying to integrate two smaller sealed subs with those Captivators without potentially causing issues to your sound.

Have you tried talking to Mark Seaton about this? He would know better than anyone.
post #4 of 89
Quote:
Originally Posted by Brad Horstkotte View Post

If that were the case, wouldn't the ported subs cancel with themselves already (sound from port cancelling its own direct output)?

No, because essentially the driver hands off output to the port. At the tuning frequency, the driver is hardly moving. The port has output when the driver doesn't.
post #5 of 89
Quote:
Originally Posted by Brad Horstkotte View Post

If that were the case, wouldn't the ported subs cancel with themselves already (sound from port cancelling its own direct output)?

I would have thought intuitively that cancellation would be due to distance differences - time alignment - and if you can independently set delay for the front and side subs, you can mitigate that?

Speculating here...

Ported subs do cancel their own output below tuning. This is why ported subs have such a rapid rolloff slope of 24db/octave below tuning.
post #6 of 89
Thread Starter 
Quote:
Originally Posted by ack_bk View Post

What about a couple midbass modules from HSU for the music? From my understanding you could have a hell of a time trying to integrate two smaller sealed subs with those Captivators without potentially causing issues to your sound.

Have you tried talking to Mark Seaton about this? He would know better than anyone.

I have a MBM-12 and I was never really happy with it. I think 2 of them would be much better, one on each side of me, so that I couldn't locate them as easily. However, after experiencing full range subs on each side of me I know that is what I want, I don't want the bass to only extend to 50hz like my MBM-12 does.

As far as asking Mark goes, I agree that is always a good idea.
post #7 of 89
How about running the Caps up to about 50/60hz and then use one Empire (maybe even two) to run from 50/60hz up to above 100hz if needed. Looking at Ricci's test of the Empire, it has big mid-bass up to beyond 120hz. Considering its price, it's probably one of the best commercial options out there for mid-bass slam. If you run two of them you should have less localization issues and you might be able to use a higher crossover than 80hz.
post #8 of 89
If you can swing it financially, stay with JTR and get a Growler or two. Mid-bass solved, no question about it.
post #9 of 89
Quote:
Originally Posted by carp View Post


So, what about having 2 ported subs and 2 sealed subs and HPF the sealed subs to around 30 hz? Would that still cause the null/cancellation/phase/whatever issues that arise from having multiple subs?

Of course I could just turn off the Caps for music and turn off the other subs for movies but if there is a way to combine them I'd like to try it.


I'm no expert, but I think this is backward. If you HPF the sealed subs, you lose the benefits of low-end room gain. I'd HPF the ported to prevent them from contributing below port tune.

Here's where I'm going with this.....How about a pair of sealed Caps up front which will take advantage of corner loading to kick ass with movies, and move the ported Caps nearfield HPFed at 25-30Hz?

I guess you could even try it both ways.....ported up front, sealed nearfield HPFed.......to see what works best. You should figure that out for me.
post #10 of 89
Hey Carp, I do not know why this was not mentioned as an option. Instead of the MBMs why not just go straight to the VTF-15s. They are also ported and can be adjusted to work best with music and yet still be able to add to the movie experience. Is there any way that Luke can bring his pair to your place to see if that would be the best solution?
post #11 of 89
Quote:
Originally Posted by Sidewayz View Post

If you can swing it financially, stay with JTR and get a Growler or two. Mid-bass solved, no question about it.

Think about this option or the comments about the Empire. I would definitely vote those two choices over eD, HSU, etc.
post #12 of 89
Thread Starter 
Quote:
Originally Posted by hometheatergeek View Post

Hey Carp, I do not know why this was not mentioned as an option. Instead of the MBMs why not just go straight to the VTF-15s. They are also ported and can be adjusted to work best with music and yet still be able to add to the movie experience. Is there any way that Luke can bring his pair to your place to see if that would be the best solution?

Great idea, but the last time Luke and I boxed up his subs and carried them to his car he said that was the last time and I don't blame him. I don't think I want to mess with that again either.

I obviously do like the HSU (blind test results) and it has a lot of tuning/ported/sealed options so dual vtf 15's is an option that's for sure.
post #13 of 89
Thread Starter 
Quote:
Originally Posted by Sidewayz View Post

If you can swing it financially, stay with JTR and get a Growler or two. Mid-bass solved, no question about it.

Quote:
Originally Posted by HuskerOmaha View Post

Think about this option or the comments about the Empire. I would definitely vote those two choices over eD, HSU, etc.

I forgot all about the Growler!!

I know the sub it was paired with was having issues at your place Husker, but did you get a chance to see what it can really do as far as music goes? I haven't read many reviews of the Growler.
post #14 of 89
Thread Starter 
Quote:
Originally Posted by spanish68 View Post

How about running the Caps up to about 50/60hz and then use one Empire (maybe even two) to run from 50/60hz up to above 100hz if needed. Looking at Ricci's test of the Empire, it has big mid-bass up to beyond 120hz. Considering its price, it's probably one of the best commercial options out there for mid-bass slam. If you run two of them you should have less localization issues and you might be able to use a higher crossover than 80hz.

I do like this idea a lot too. I've never heard the Empire for music (I arrived late), just briefly for movies and it was over matched by Archaea's room and didn't stand much of a chance so it wasn't a fair audition.

I've often read that it is a great music sub. Counsil has Empires and Submersives and I remember him saying at the GTG last May that he preferred the Empire slightly to the Submersive on the music portion of the audition at Archaea's place.
post #15 of 89
Thread Starter 
Quote:
Originally Posted by the Son View Post

I'm no expert, but I think this is backward. If you HPF the sealed subs, you lose the benefits of low-end room gain. I'd HPF the ported to prevent them from contributing below port tune.

Here's where I'm going with this.....How about a pair of sealed Caps up front which will take advantage of corner loading to kick ass with movies, and move the ported Caps nearfield HPFed at 25-30Hz?

I guess you could even try it both ways.....ported up front, sealed nearfield HPFed.......to see what works best. You should figure that out for me.

Oh how I would love this option!!!! And you're right, it makes more sense to HPF the ported subs since they don't dig as deep. However, I don't think I can do over 4 grand worth of subs anytime soon.

Hmmm... looks like Growlers are a grand a piece, so are the HSU's which I already knew I just wasn't thinking.....

At that price it starts getting tempting to just get another pair of passive Caps since I know 100% that they sound awesome for music in the near-field placements. However, I really don't want to spend that much.

That leads me back to the Empire...
post #16 of 89
Exactly what I was meaning here. If you need more midbass or near field, I was thinking of the picture of counsils? theater with the empires. Get a pair of those.

To keep the JTR look going, add the Growler. It certainly has the output. I wish we could have got the duo going at the gtg just ran out of time.

Personally I would just get two more passive caps if I were you.
post #17 of 89
You will know very little until you begin measuring !!! You will understand why movies didnt sound good and music did. More subs in the right location will dramatically improve the FR at your seating location.

I encourage you to take the next step in this very scientific hobby and get some tools !!!
post #18 of 89
Thread Starter 
Quote:
Originally Posted by kgveteran View Post

You will know very little until you begin measuring !!! You will understand why movies didnt sound good and music did. More subs in the right location will dramatically improve the FR at your seating location.

I encourage you to take the next step in this very scientific hobby and get some tools !!!

I agree. Luke and I took measurements and calibrated the Caps flat in their current up front position but didn't have time to move them back and do measurements again - we spent a lot of time demoing movies too of course.

He came over around 2:00 and when he left I thought it would be like 5:00 or close to that since I wasn't watching the clock - nope, 7:00!! Time flies when you are messing with subs.

I need to just break down and buy an omnimic...
post #19 of 89
Quote:
Originally Posted by carp View Post

I agree. Luke and I took measurements and calibrated the Caps flat in their current up front position but didn't have time to move them back and do measurements again - we spent a lot of time demoing movies too of course.

He came over around 2:00 and when he left I thought it would be like 5:00 or close to that since I wasn't watching the clock - nope, 7:00!! Time flies when you are messing with subs.

I need to just break down and buy an omnimic...

For the brief 2 months i have had one, it is a MUST as you know, i'm curious how they measured at the sides
post #20 of 89
Thread Starter 
To be clear, it's not a mid-bass problem. The Captivators have plenty of that and I can eq in a mid-bass hump since they have output to spare in that region.

It's a near-field thing. I get a lot more tactile sensation from subs that are closer. I can get that same feel from further away, the catch is you have the volume much louder to get it and that doesn't make the rest of the family happy.

If there is a way to get that same effect from subs that are far away I would love to figure that out!! That would save me a lot of cash.

Do you guys know what I'm saying about the near-field thing?
post #21 of 89
Thread Starter 
Quote:
Originally Posted by kgveteran View Post

For the brief 2 months i have had one, it is a MUST as you know, i'm curious how they measured at the sides

Yeah, me too. Like I said in the above post, I do believe it's a near-field thing

BUT

The smart thing to do would be to buy an onmimic, measure the frequency response with Caps flanking me on the side walls, and then try to mimic that with the Caps back up front using the sms-1... right?
post #22 of 89
Thread Starter 
Pictures of the two placements in the room.

I don't have the subs facing like that now though (1st pic), when Luke came over we he showed me how I had a large dip between 80-100 hz and when we faced the subs 90 degrees facing the side walls (still sitting in the same spot just rotated) that dip went away and I had around 6db gain in that 80-100 hz region.





Next pics show near-field placement, LP is the right side of the darker brown love seat.



post #23 of 89
how about just getting 2 more caps ?
post #24 of 89
Quote:
Originally Posted by otk View Post

how about just getting 2 more caps ?

yep
post #25 of 89
Quote:
Originally Posted by otk View Post

how about just getting 2 more caps ?

I was thinking the same thing. Much easier to blend the four together I would suspect, but man that is a lot of bass
post #26 of 89
Carp,

I think your quest for nearfield placement is absolutely the right one to embark! Nearfield placement makes such a dramatic difference in tactile feel. IMO, if anyone can do nearfield placement, they should 100% do it!

Honestly, I think your answer is: invest in an omnimic and an outboard EQ (BFD, eQ.2, etc.) or perhaps an SMS-1 first.

You made the statement that movies sound horrible nearfield...I find that very odd especially with your Caps. Movies should actually sound better nearfield if tuned correctly! There's one thing about music 'punch' nearfield that's impressive, but it is equally impressive with ULF nearfield.

It could be that the way your subs were facing each other created a big null nearfield, and simply rotating them 90 degrees may change it entirely. Or perhaps adjusting the phase on one or the other would correct things. Without having a tool to know what's going on, you're shooting in the dark.

Regardless, at the end of the day, if you're still not happy with the nearfield placement, you'll STILL need an omnimic or equivalent tool to dial in all 4 subs, IMO. So, you could really take this path in steps; Buy the FR tool, test placement, phase, etc., if you still don't like it, get extra subs. You'll still need the tool to dial it in, so no loss there.

As far as mixing ported and sealed....ugh, I just got done doing it. The result is fantastic to my ears (and body), but if I didn't have the right tools (omnimic, eQ.2), I would have never been able to dial them in to my liking.

Additionally, if you don't get the same type of subs, you will also get a different 'sound' as compared to just 1 brand. This could be a better or a worse sound, but it will most likely be a different sound.
post #27 of 89
I still think your best bet for that nearfield "punch" is a pair of JTR Growlers. The frequency range where that punchy sound lies is right in the Growlers wheelhouse. It is much more efficient in that range than a Captivator and would allow you to cross the Cap over lower to play into its strengths better as well.
post #28 of 89
Thread Starter 
Quote:
Originally Posted by dominguez1 View Post

Carp,

I think your quest for nearfield placement is absolutely the right one to embark! Nearfield placement makes such a dramatic difference in tactile feel. IMO, if anyone can do nearfield placement, they should 100% do it!

Honestly, I think your answer is: invest in an omnimic and an outboard EQ (BFD, eQ.2, etc.) or perhaps an SMS-1 first.

You made the statement that movies sound horrible nearfield...I find that very odd especially with your Caps. Movies should actually sound better nearfield if tuned correctly! There's one thing about music 'punch' nearfield that's impressive, but it is equally impressive with ULF nearfield.

It could be that the way your subs were facing each other created a big null nearfield, and simply rotating them 90 degrees may change it entirely. Or perhaps adjusting the phase on one or the other would correct things. Without having a tool to know what's going on, you're shooting in the dark.

Regardless, at the end of the day, if you're still not happy with the nearfield placement, you'll STILL need an omnimic or equivalent tool to dial in all 4 subs, IMO. So, you could really take this path in steps; Buy the FR tool, test placement, phase, etc., if you still don't like it, get extra subs. You'll still need the tool to dial it in, so no loss there.

As far as mixing ported and sealed....ugh, I just got done doing it. The result is fantastic to my ears (and body), but if I didn't have the right tools (omnimic, eQ.2), I would have never been able to dial them in to my liking.

Additionally, if you don't get the same type of subs, you will also get a different 'sound' as compared to just 1 brand. This could be a better or a worse sound, but it will most likely be a different sound.

Thanks for the advice, I enjoyed reading through your sub progression the last time we crossed paths on another thread.

I do have a SMS-1, but unfortunately I'm sending it in to Velodyne. It makes a loud thump anytime I cut the audio signal which means it thumps when I change channels watching tv, when I fast forward the dvr, when I switch inputs, etc. It was driving me crazy.

So, I'll have to wait until I get that back. I do need to get an onmimic though.

I'm glad to hear you say that near-field made a big difference for you and that you figured out how to match ported and sealed.
post #29 of 89
Weren't you a favorite of sealed subs? Get two more caps or a couple growlers. Easy to sell if you need to if they don't work out and you already have and like your JTR stuff, right?
post #30 of 89
Quote:
Originally Posted by carp View Post

To be clear, it's not a mid-bass problem. The Captivators have plenty of that and I can eq in a mid-bass hump since they have output to spare in that region.

It's a near-field thing. I get a lot more tactile sensation from subs that are closer. I can get that same feel from further away, the catch is you have the volume much louder to get it and that doesn't make the rest of the family happy.

If there is a way to get that same effect from subs that are far away I would love to figure that out!! That would save me a lot of cash.

Do you guys know what I'm saying about the near-field thing?

Until about 2 or 3 months ago i had to listen close to 0db MV to get the sensation i wanted from my subwoofers, not now. I upgraded Audyssey to DEQ.... I cant tell you how well it adjusts bass to the level being played. I rarely get volume above -15db MV....

.....on the other hand, 4 subs would be pretty cool sounding for sure.
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