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ranger098
09-26-2013, 03:21 PM
I have read different threads on different forums and hear equally that both are better, so which is it? I am talking about in a BOAT application. I personally prefer ported in my truck, and have a good amount of experience making ported and sealed boxes for auto applications. I really believe that ported works well in cars becuase of the cabin pressure created, so what happens in the open area of a boat? I am installing one 12" sub at the driver's feet of my 04 X2. I know ported is a bigger box, and am willing to make the bigger box if it will produce more volume, just as in a car application. My concern is that the sub will tend to 'Fart' and distort without the cabin pressure of a car. Thanks all!

David Analog
09-26-2013, 04:27 PM
Your assessment of why a ported woofer works in a car is way off. But that's okay.
Ported (bass-reflex) offers similar overall output as compared to a sealed (air suspension)enclosure. Let me explain.
Sealed typically has a bit better transient response. Sealed rolls off earlier, more gradually, but ultimately extends deeper.
Ported is a tuned circuit that sacrifices output & extension well below the meat of the bass but gives you more output (+3dB in a conservative alignment) throughout the most coveted bass region and provides an extra one/third octave of low bass extension before reaching its half power point.
You can manage what you want a bass-reflex enclosure to be. You can have a one note resonator with a giant boost over a narrow peak range (SPL monster) or you can create a well-damped broad-band linear response for SQ.
A majority of the world's most expensive esoteric home speakers are bass-reflex (many selling for nearly $200K per pair). Believe me, those owners will not accept anything but perfection. So saying that one sounds better than the other is nonsense. The difference is absolutlely in the driver/enclosure selection and the execution.
No, a bass-reflex enclosure will not 'Fart' if done correctly.

MLA
09-26-2013, 09:06 PM
Your assessment of why a ported woofer works in a car is way off. But that's okay.
Ported (bass-reflex) offers similar overall output as compared to a sealed (air suspension)enclosure. Let me explain.
Sealed typically has a bit better transient response. Sealed rolls off earlier, more gradually, but ultimately extends deeper.
Ported is a tuned circuit that sacrifices output & extension well below the meat of the bass but gives you more output (+3dB in a conservative alignment) throughout the most coveted bass region and provides an extra one/third octave of low bass extension before reaching its half power point.
You can manage what you want a bass-reflex enclosure to be. You can have a one note resonator with a giant boost over a narrow peak range (SPL monster) or you can create a well-damped broad-band linear response for SQ.
A majority of the world's most expensive esoteric home speakers are bass-reflex (many selling for nearly $200K per pair). Believe me, those owners will not accept anything but perfection. So saying that one sounds better than the other is nonsense. The difference is absolutlely in the driver/enclosure selection and the execution.
No, a bass-reflex enclosure will not 'Fart' if done correctly.

Where's the "like" button when you need it.

Like David said, a ported will yield more output. But, not every woofer performs or sounds best in a ported. Some woofers do better in a sealed, some in a ported and some are middle of the road and go both ways. Ported and sealed also sound different. Some people like one over the other.

BudmanV24
10-01-2013, 08:55 AM
One factor I've always thought about is that a sealed enclosure should keep the woofer dryer...since I know a lot of ppl use non marine subs.

JimN
10-01-2013, 09:24 AM
I have read different threads on different forums and hear equally that both are better, so which is it? I am talking about in a BOAT application. I personally prefer ported in my truck, and have a good amount of experience making ported and sealed boxes for auto applications. I really believe that ported works well in cars becuase of the cabin pressure created, so what happens in the open area of a boat? I am installing one 12" sub at the driver's feet of my 04 X2. I know ported is a bigger box, and am willing to make the bigger box if it will produce more volume, just as in a car application. My concern is that the sub will tend to 'Fart' and distort without the cabin pressure of a car. Thanks all!

Where do you want to place the box? If it's in an area where the floor, side panels and other surfaces act as a boundary for the acoustic output, these boundaries will act to boost the low frequency output, so it may not be necessary to use a vented design. However, this doesn't mean you can use the same driver. Woofers designed for sealed don't work for vented and vice-versa and one of the Theile-Small parameters can be used to ball-park this (Qts), in order to scan through the wide variety of woofers. In a placement like this, a sealed enclosure can do a better job than vented, especially if the port tuning results in a large peak.

David Analog
10-01-2013, 10:16 AM
One factor I've always thought about is that a sealed enclosure should keep the woofer dryer...since I know a lot of ppl use non marine subs.

That's definitely true if the woofer uses a paper cone whether or not it is behind an exterior poly dustcap.

Greenster
10-02-2013, 12:37 AM
Keep it sealed for marine applications. If you build it correctly then you will have more than enough good clean bass. Look on the hometheatershack forum for a lot of great info.

bsloop
10-02-2013, 11:00 AM
IF you have read other threads, good info but nothing that has not been said in every other thread.

Ported is my preference for non-salt water applications. A decently designed box will not fart but will provide the boom most people are looking for. Sealed will often leave you wanting more.
Go 12" vs 10" if at all possible.
Look for speakers with rubber surround and plastic cone for minimal problems.

skitilldark
10-02-2013, 01:11 PM
I'm certainly no where near the expert level of those who have already weighed in, but I can tell you though that I have a ported enclosure on my front 10" sub, and a non ported on the rear 12" (same brand) and the 10 kicks the crap out of the 12.

markismm
10-02-2013, 02:06 PM
I have had three different subs in my boat and all required different enclosures. MY most recent sub is s kicker solobaric L7 12. I built a box for it sealed and one for it ported. The ported box ended up providing a lot more sound in the open air than the sealed box. I certainly prefer this sub in a ported box. Again, those who have indicated that the sub itself should dictate the type of enclosure are correct though as my two prior subs performed and sounded much better in a sealed box. What type of sub are you running?

ol1970
10-25-2013, 04:08 PM
I have a JL 13W7 in a ported box run by a 750/1, in my 07 X Star...it is truly amazing to me and will draw a crowd on a sandbar with people amazed at the clarity and response of the entire system together. I'm thinking of going with 2 of them in my next boat unless I can come up with a better option. I've not really come across a boat that sounds better from a bass output or response standpoint...but I love this stuff so I'd like to hear something bigger and badder!

David Analog
10-25-2013, 04:38 PM
I have a JL 13W7 in a ported box run by a 750/1, in my 07 X Star...it is truly amazing to me and will draw a crowd on a sandbar with people amazed at the clarity and response of the entire system together. I'm thinking of going with 2 of them in my next boat unless I can come up with a better option. I've not really come across a boat that sounds better from a bass output or response standpoint...but I love this stuff so I'd like to hear something bigger and badder!

While the JL Audio HD750/1 is a beast, in an open field environment, I would say that is light power for a 13W7. You haven't heard the 13W7 reach its full dynamic ability yet....not speaking of volume, but rather maximum dynamic/transient/attack/tight. A JL Audio Slash 1200/1 per sub is ideal while the HD1200/1 is next in line. That is a very massive sub to drive & control, and in an open boat power seems to flash evaporate very differently from the contained cabin of a car, truck or SUV. So typically you have to be at the top of or just above the woofer thermal rating, especially in consideration of JL Audio rating their subs power a bit on the conservative side.

JimN
10-25-2013, 05:27 PM
I have a JL 13W7 in a ported box run by a 750/1, in my 07 X Star...it is truly amazing to me and will draw a crowd on a sandbar with people amazed at the clarity and response of the entire system together. I'm thinking of going with 2 of them in my next boat unless I can come up with a better option. I've not really come across a boat that sounds better from a bass output or response standpoint...but I love this stuff so I'd like to hear something bigger and badder!

Here ya go- if you can find a way, it will go lower than anything you have heard.
http://dougronald.com/sound_images.htm

ol1970
10-25-2013, 05:47 PM
While the JL Audio HD750/1 is a beast, in an open field environment, I would say that is light power for a 13W7. You haven't heard the 13W7 reach its full dynamic ability yet....not speaking of volume, but rather maximum dynamic/transient/attack/tight. A JL Audio Slash 1200/1 per sub is ideal while the HD1200/1 is next in line. That is a very massive sub to drive & control, and in an open boat power seems to flash evaporate very differently from the contained cabin of a car, truck or SUV. So typically you have to be at the top of or just above the woofer thermal rating, especially in consideration of JL Audio rating their subs power a bit on the conservative side.

O.k. so I'm with you...I argued that I should have gone with the 1200/1, but they assured me the 750 was the way to go, honestly it hits really hard & I've never heard it the other way so I've always wondered what if...

So in a new '14 X Star how crazy would it be for me to put (2) 13W7's each with their own 1200/1? Also I'm wanting to power the 7.7 tower speakers with a HD600/4 for extra power, is there a better alternative? One final question...the boat comes with (2) 600/6 amps, one runs in boat and the other currently runs the towers. I'd like to use both 600/6's to run just the in boat speakers (bridged). Is this a bad idea & will it give me a good result?

David Analog
10-25-2013, 07:30 PM
O.k. so I'm with you...I argued that I should have gone with the 1200/1, but they assured me the 750 was the way to go, honestly it hits really hard & I've never heard it the other way so I've always wondered what if...

So in a new '14 X Star how crazy would it be for me to put (2) 13W7's each with their own 1200/1? Also I'm wanting to power the 7.7 tower speakers with a HD600/4 for extra power, is there a better alternative? One final question...the boat comes with (2) 600/6 amps, one runs in boat and the other currently runs the towers. I'd like to use both 600/6's to run just the in boat speakers (bridged). Is this a bad idea & will it give me a good result?

Sure, two 13W7s with an HD1200 per each woofer is the right combination. You just have to understand that when they designed a W7 to go a little deeper with a longer excursion that in itself makes the speaker internal efficiency just a bit lower, than say a W6 for example. This slight trade-off is unavoidable. The benefits of the W7 are absolutely concrete but only IF you give them all the power they deserve. And then a 13.5-inch is a ton of moving mass to accelerate and control.
For the in-boat speakers....let's say you have three pair 7.7s in the coaming. Bridging the two six channel amplifiers into six total channels will give you 200 watts per each M7.7" speaker. It doesn't get any better. Because the HD600/4 is strictly regulated, its four channels deliver about the same output as eight channels of the XD series bridged bridged into four. Plus, the HD600/4 has two power supplies just like dual discrete two channel amplifiers built into a single chassis. So its a beast. Either way will be awesome leaving no potential unrealized. It's enough midbass attack to make you flinch on a rimshot. Also, with so much subwoofer, you would need a ton of competing midbass from your 7.7" satellites. The bass sound quality is only as good as the balance between the fundamentals and harmonics. The bass tonal construction really comes from the 7.7s. If the subs over-drive the sats, then the bass begins to sound very indiscriminate.

ol1970
10-25-2013, 07:44 PM
Thanks for the input...so two more quick questions:

I have read in other posts where having (2) unique ported subs in different locations on the boat would cancel each other out or be inefficient? Realistically 1 13W7 is more than enough, but hey if two would be literally twice as good...I'm in! I just don't want to do something technically stupid and it would not make a noticeable difference.

Last question...would a 750/1 be a better choice for the tower speakers than the 600/4? If I update my sub to the 1200/1 I'll have the 750/1 available to use somewhere.

thanks!!!

David Analog
10-25-2013, 09:03 PM
Thanks for the input...so two more quick questions:

I have read in other posts where having (2) unique ported subs in different locations on the boat would cancel each other out or be inefficient? Realistically 1 13W7 is more than enough, but hey if two would be literally twice as good...I'm in! I just don't want to do something technically stupid and it would not make a noticeable difference.

Last question...would a 750/1 be a better choice for the tower speakers than the 600/4? If I update my sub to the 1200/1 I'll have the 750/1 available to use somewhere.

thanks!!!

Yes, the HD750/1 makes better sense for the tower because it is simply 25% more power.

Two subs in different locations in an open boat definitely has negative issues. Contrastly, in a contained home theater room, you can in some cases purposely use two or multiple subs in different locations to cancel room problems and cancel listener location bias. But you are also interfacing with boundaries, like walls. In a boat, two sub locations can give you somewhat more output but will never give you near the same output as two identical subs in the same location, oriented the same, and loading into symmetrical boundaries. Due to phasing problems, you get hot and cold spots in the boat and you get a smeared tonal construction. No second sub in a secondary location will perform as well as the primary sub in the most optimum location. So if you can't collect the two or set up an identical left and right at midship, then the second sub and additional amplifier may not be worth the extra investment.
Another approach worth mentioning is if the designer/installer can load the sub and port into the open cockpit so that it is completely direct radiating and totally sealed off from the helm or bench seating console that contains the enclosure, both the bass output and the bass sound quality will be MUCH improved. Some boats cooperate more than others.

ol1970
10-25-2013, 11:24 PM
Thanks David! My gut tells me to just go with the 1 sub and update to the 1200/1 amp...it should make the 13W7 come alive even more than with the current 750/1. I'm just afraid of not going big enough the first time. I appreciate your knowledge and insight! Any other advice you could bestow upon me to make this boat sound as amazing as possible?

JimN
10-26-2013, 12:40 AM
Get some of this, just in case-

Rossterman
10-26-2013, 01:31 AM
Get some of this, just in case-

Love it! Always remember my friends saying " Lucas electrics, inventors of darkness!"

Amazing that any old British cars or motorcycles even run anymore

JimN
10-26-2013, 09:55 AM
Love it! Always remember my friends saying " Lucas electrics, inventors of darkness!"

Amazing that any old British cars or motorcycles even run anymore

Q- "Why do British men drink warm beer?"

A- " Lucas Refrigeration".