Ported vs. Unported speakers

[March Audio]

2 hours ago, murrmax said:

 

 

 

 

Actually a sealed design will have greater bass extension, however the ported speaker will be louder at specific frequencies frequency and loudness at a specific frequency are different things..  Most speakers use ports because it's more practical and cost effective for manufacturers to provide consumers with what they want and fits the use case.  

 

 

 

 

 

 

What about infinite baffle?

 

 

 

Whilst your point is taken, I think it's more about what I would term "usable" / "useful" extension.

 

In your example the 2 cross at around -20dB.  What's going on below this is largely irrelevant.  If you look at the normal F3, F6 and F10 points ported is way ahead.

 

 

 

Edited November 2, 2023 by March Audio

[cheekyboy]

7 hours ago, Keith_W said:

Thanks for your feedback @POV and @andyr. I have edited the poll questions. 

 

Hello Keith, regarding your poll, I tried to check the first three choices, Ported, Sealed and Other, but unfortunately it does not allow me to do this. I have three systems playing into the same space here and the loudspeakers in each system are different enclosure designs, being ported, sealed and TL I play all three types of loudspeakers every day, so can you edit your poll to allow me to check those three enclosure types? No big deal if this isn't possible.

 

Cheers,

 

Keith

 

On 30/10/2023 at 10:42 AM, cheekyboy said:

I currently have three different systems playing largely into the same space and the loudspeakers are all different design types, being bass reflex, sealed and transmission line. I enjoy all three types of loudspeakers and each has their own strengths, but I do find myself listening more often to the sealed 2 ways, which have the bass augmented with two 10” sealed subs. I feel this slight preference for these loudspeakers is because of the tonal quality of the sealed 2 ways more than anything else, but it has nothing to do with any perceived preference for sealed enclosures over bass reflex or transmission line for that matter.

 

[andyr]

8 hours ago, murrmax said:

 

What about infinite baffle?

 

 

Isn't that just another name for a sealed box?

 

[cheekyboy]

16 minutes ago, andyr said:

 

Isn't that just another name for a sealed box?

 

 

Hello Andy,

 

I think that over time the term 'infinite baffle' has come to mean a sealed enclosure, but in fact that wouldn't necessarily be the case. The term 'baffle' is generally understood to be the panel the driver/s are mounted on, but I think this term morphed with time to mean the enclosure/box.

 

Cheers,

 

Keith

[BioBrian]

I don't see that the poll would help anybody here, but maybe that's just me. Surely there's enough conflict in the world, without further separating people into black and white opinions, after such a lot of good ground has been covered in the thread.

 

If there's to be a poll, maybe it could be to sort out questions like:

 

- Are you here just to reinforce your opinions/prejudices about sealed vs ported?

 

- Are you here to continue learning about different speaker designs, and how they could be useful in your life?

[Cloth Ears]

9 hours ago, Keith_W said:

Thanks for your feedback @POV and @andyr. I have edited the poll questions. 

As I use both sealed and ported, there is no answer in the poll for me.

[cheekyboy]

1 minute ago, Cloth Ears said:

As I use both sealed and ported, there is no answer in the poll for me.

 

Yep, me also Jonty, and I have TLs as well in the same room, so that's why I asked if Keith can edit the poll to allow us to check multiple choices.

 

Cheers,

 

Keith

[Cloth Ears]

1 hour ago, cheekyboy said:

 

Hello Andy,

 

I think that over time the term 'infinite baffle' has come to mean a sealed enclosure, but in fact that wouldn't necessarily be the case. The term 'baffle' is generally understood to be the panel the driver/s are mounted on, but I think this term morphed with time to mean the enclosure/box.

 

Cheers,

 

Keith

Infinite baffle is generally a sealed box which has a Qtc of less than 0.5 - which means you need drivers that do not require much in the way of air-mass control to prevent them over extending. It's also come to mean where you are using "everywhere outside the room" as your enclosure (so, open baffle, but with no openings).

[murrmax]

Quote

Isn't that just another name for a sealed box?

 

Technically it is but the driver is not using the sealed volume as a suspension device  

[andyr]

3 minutes ago, murrmax said:

Technically it is but the driver is not using the sealed volume as a suspension device  

 

Aah, OK - yes I can understand that.  

 

6 minutes ago, Cloth Ears said:

It's also come to mean where you are using "everywhere outside the room" as your enclosure (so, open baffle, but with no openings).

 

We seem to be well inside the looking glass, here!  

 

[cheekyboy]

19 minutes ago, Cloth Ears said:

Infinite baffle is generally a sealed box which has a Qtc of less than 0.5 - which means you need drivers that do not require much in the way of air-mass control to prevent them over extending. It's also come to mean where you are using "everywhere outside the room" as your enclosure (so, open baffle, but with no openings).

 

Yep, and hence the confusion, Jonty. It's the mixing of terms relating to the baffle to mean the box or enclosure, regardless of the amount of mechanical damping applied to the driver.

 

Cheers,

 

Keith

[Cloth Ears]

18 minutes ago, andyr said:

 

We seem to be well inside the looking glass, here!  

 

I keep thinking of Wonko the Sane, from "So Long and Thanks for all the Fish". Where he built an asylum to keep the world in after reading the instructions on a packet of toothpicks. I've seen subwoofers designed along the same principle - where a roof-space (which isn't really sealed, except from above) or a garage is sued as the 'enclosure'.

[davewantsmoore]

On 2/11/2023 at 2:26 PM, cheekyboy said:

Hello davewantsmore, I'm not sure which of my posts you're responding to, as there is no dialogue in the quote box other than 'Hello' and therefore I'm also not sure what it is that you don't completely disagree with where I'm coming from.

Just generally that subs can sometimes be a backwards step and/or sometimes aren't warranted.

 

On 2/11/2023 at 2:26 PM, cheekyboy said:

My initial posts here were made mainly to make the point that there are good and bad designs in both ported and sealed loudspeakers and that excellent results can be had from both types of enclosure and to refute the often stated blanket assumption that ported loudspeakers equal deep bass response and that sealed loudspeakers equal tight or lean bass response........neither assumption is correct.

Very much.

[davewantsmoore]

On 2/11/2023 at 2:26 PM, playdough said:

@joz Going from 8 x 12 " woofers to 16 in a huge area will halve the cone excursion for the current SPL Max, plus all manner of other good things like, less distortion at the lowest octaves.

Bass might even sound a little cleaner at reasonable listening levels, due to the drivers/amps not being tortured to P and X Max.

Headroom for +6dB for bass, on top of what is already achieved, is quite a lot of entertainment reinforcement. 

 

More SPL and/or less excursions or distortion .... is really not what I think would be the drawcard, unless, somehow, the current crop of woofers was having trouble at the current SPL, which would be super duper unlikely IMVHO.

 

The big drawcard is the the new woofers will not be placed in the same location as the old ones...... as this will almost certainly make some difference.

 

 

[joz]

On 2/11/2023 at 1:58 PM, davewantsmoore said:

Finding out if you actually have a problem to solve doesn't need to cost lots.

 

True, I tend to be( in my mind)the suck it a see type.  I really need to learn some more skills or default to those that can just do it.
 

On 2/11/2023 at 2:03 PM, March Audio said:

 

https://www.minidsp.com/products/acoustic-measurement/umik-1

 

https://www.roomeqwizard.com/

 

Considering how much people are prepared to pay for their hifi kit, I dont think $125 is a lot to spend.

 
No not at all , I think I’ve got a mike around here somewhere too!

Just not to good with driving eq wiz.

Just need the patience to learn and how to drive it.

[playdough]

3 hours ago, davewantsmoore said:

More SPL and/or less excursions or distortion .... is really not what I think would be the drawcard, unless, somehow, the current crop of woofers was having trouble at the current SPL, which would be super duper unlikely IMVHO.

 

A bloke mentioned to me once he visited Joe and the Illuminators, did a quick SPL measurement from some 15m away @ 123dB, said it sounded a little thin in the sub 80 Hz department, but good.

How can doubling the bass woofer count be in any way "not a drawcard" of coarse it would be, seriously. Give me your reasoning,

I;ve heard some things but that mmmmmm,,,,,,,,,,,,,,,what's better than  2 x 18" long throw drivers, in a single sealed 200 litre cab,,,,,,,,,,,another cab to make a stereo pair,,,,,,,,,physics again Dave.

What do you do at an ACDC Concert run a pair of subs or 30 subs. What would the Crowd recon of 2 subs, not a lot.

[March Audio]

11 minutes ago, playdough said:

did a quick SPL measurement from some 15m away @ 123dB,

 

That does seem unlikely.

[joz]

44 minutes ago, March Audio said:

 

That does seem unlikely.

I know I’ve had it up there but even I’m not sure at 15m?
But then again I’ve never measured from there?

 

@playdough Thin? Again perhaps depending on what was being played?

I know I run the subs about 4db hotter than flat. Without that I’d say yes the system does sound a bit lean.

 

I may one day even blend the pair of JBL ported 18”s. But again they are in the same plane as the mains. So maybe not.

 

Edited November 3, 2023 by joz

[playdough]

16 minutes ago, March Audio said:

That does seem unlikely.

That's what I thought however the Bloke is trustworthy, non BS type of Backline Guy and owns a stereo that makes similar big numbers, maybe more. He was using a calibrated mic and Audio Control RTA so the instrument was trustworthy as well

6 minutes ago, joz said:

I may one day even blend the pair of JBL ported 18”s. But again they are in the same plane as the mains. So maybe not.

So the JBL's are not going ? 100 w on each one of those with a rough filter would be a start. It doesn't matter if they play in the "same plane" ? Stand them up front and centre.  

Shurly  you have some likely candidates in Melb. that would be willing to help set them up. Offer coffee/beer

[playdough]

29 minutes ago, joz said:

Thin? Again perhaps depending on what was being played?

After listening to Dynacord Cobra stacking line array and others, yea, a little.

May I add, however he had never seen such a  pair of beast speakers in rose wood veneer  and was shocked.

 

EDIT, add the JBL's for Party Mode.

Put them away after the party.

https://www.audiosource.com.au/line-array/1379-Ground-Stackable-Line-Array-System.html

and then ad 2 more subs to the stack

Edited November 3, 2023 by playdough

[playdough]

Sorry getting off topic into horn loaded Bass Enclosures. 

 

Edited November 3, 2023 by playdough

[joz]

@playdough

the 18s are JBL 2245s each in a ported 250 ltre boxes . They are currently connected and in the pics previously but only connected via the HT .1 outputs, so they add nothing to the 2 channel. Though they are only for movies and eq’d to blend to  the mains during movies .

Yep I may ask @frednork to help measure Mark?

Edited November 3, 2023 by joz

[playdough]

21 minutes ago, joz said:

Though they are only for movies and eq’d to blend to  the mains during movies

I'm fairly sure they will reproduce deep slap bass as well as the kick drum, fairly tightly at an insane SPL. 2 pairs of 2245 Drivers in ported enclosures.(100wrms per channel)  is along the same line as the other highly efficient ported enclosures (we don't complain much)

If you are in a very large, hard, solid construction, might be an idea to HP brick wall the JBL's @32 Hz or similar type of tune. Most music doesn't have lots of content below that, a little for some, but rare. Really low frequencies mostly reek havoc in small hall sized lodgings, that are solid. Timber, all good.

No worries at 85dB, but +100, lights up the place with ULF resonations.

Might work really well and would take the pressure of the Illuminators, for parties.

It is that time of year.

 

Edited November 3, 2023 by playdough

[playdough]

@joz

If you build enclosures for the , 8 x 12 " drivers, you know they have to be rose wood veneered the same, and most likely sealed enclosures to match the SGR Illuminators

[frednork]

1 hour ago, joz said:

Yep I may ask @frednork to help measure Mark?

yep sure, will pm to organise. You might have to turn it down as the mic will only do 140db