DiyMobileAudio.com Car Stereo Forum banner

1 - 17 of 17 Posts

·
Registered
Joined
·
77 Posts
Discussion Starter #1
Vent placement poll.

I’m considering the following options:

Centered and as far forward as possible.

To the left as far to the back as possible (firing towards window basically).

To the left as far forward as possible (firing into headliner.

Any thoughts before I cut take the router to the enclosure?

FWIW I will be making a plug/volume reducer for sealed operation and maximizing storage capacity and minimizing obnoxiousness.
 

Attachments

·
Premium Member
Joined
·
3,350 Posts
Up periscope?

I know the reason why People use PRs.
But if the goal is also flashy, then the vent makes sense.
 

·
Registered
Joined
·
1,276 Posts
Maybe sit in there and look in the rear view mirror. One of them might work better :D
(thinking put it on the left side, ... and forward for practical reason - can use floor space near the hatch opening)
Man... that must be the biggest port on diyma!
 

·
Registered
Joined
·
1,914 Posts
I think to the left and back looks the best but i might be biased as i just installed a septic tank in that configuration.
 

·
Registered
Joined
·
77 Posts
Discussion Starter #6
This is for two 10W6v3’s. The enclosure will likely be run in the sealed configuration for most of it’s life. Internal volume is 2.65ft^3.

Without Polyfil, a 24in port length should result in a 31 Hz tuning frequency; based on some preliminary research (https://www.glasswolf.net/papers/polyfill.html) it is looking like I may be able to achieve a sub 30Hz tune with a port length of less than 20" if i achieve a stuffing density of approximately .85 lb/ft^3.

A 20” port length would pretty much be hidden behind the rear seat center headrest but offsetting to the left does make sense in terms of visibility if I’m trying to tune lower than 30Hz.

And yes, is somewhat of an unusual configuration but i’m okay with that as the sealed version will be very low-key.
 

·
Registered
Joined
·
77 Posts
Discussion Starter #8
Both. It’s modular. Once the hole and counterbore are routed into the enclosure I will choose between a round plug that seals (and reduces enclosure volume) the hole or an aero port of variable length for tuning.
 

·
Registered
Joined
·
92 Posts
I see. The recommended net sealed volume is 0.55 cu ft. So what kind of plug gets you to reduce the enclosure down closer to 1.1 cu ft and be strong enough to withstand the internal pressure? I’m not trying to be a doucher, just trying to understand/ learn.. how will the subs sound sealed in a way bigger box?
 

·
Premium Member
Joined
·
3,350 Posts
I think to the left and back looks the best but i might be biased as i just installed a septic tank in that configuration.
I had the coffee out the nostrils ^here^.


Both. It’s modular. Once the hole and counterbore are routed into the enclosure I will choose between a round plug that seals (and reduces enclosure volume) the hole or an aero port of variable length for tuning.
A forum tromboner?
 

·
Registered
Joined
·
77 Posts
Discussion Starter #11
I see. The recommended net sealed volume is 0.55 cu ft. So what kind of plug gets you to reduce the enclosure down closer to 1.1 cu ft and be strong enough to withstand the internal pressure? I’m not trying to be a doucher, just trying to understand/ learn.. how will the subs sound sealed in a way bigger box?
I never really had plans of getting down to the recommended sealed volume with the plug/seal only, In fact, I will only get down to 2.3 ft^3 with a solid plug. I have absolutely no concerns with achieving the required structural integrity with the part that will replace the port, but do know that I won’t be able to reduce internal volume sufficiently with just the plug.

The thing is, once removed, the plug allows for the placement/securement of any variety of object that occupy volume. So it may take a bit more work when switching back and forth between sealed and ported, but that’s okay as I really don’t think it will be a common occurrence.

In WinSD it looked as if the larger sealed enclosure volumes resulted in more bottom end (albeit with the need of filters to prevent over excursion as the volumes increased dramatically) and it seemed like maximizing the volume for my available space didn’t have a downside while allowing for a ported alternate configuration.
 

·
Premium Member
Joined
·
3,350 Posts
I never really had plans of getting down to the recommended sealed volume with the plug/seal only, In fact, I will only get down to 2.3 ft^3 with a solid plug. I have absolutely no concerns with achieving the required structural integrity with the part that will replace the port, but do know that I won’t be able to reduce internal volume sufficiently with just the plug.

The thing is, once removed, the plug allows for the placement/securement of any variety of object that occupy volume. So it may take a bit more work when switching back and forth between sealed and ported, but that’s okay as I really don’t think it will be a common occurrence.

In WinSD it looked as if the larger sealed enclosure volumes resulted in more bottom end (albeit with the need of filters to prevent over excursion as the volumes increased dramatically) and it seemed like maximizing the volume for my available space didn’t have a downside while allowing for a ported alternate configuration.
You could use a PR in the plug.
What frequency is that port intended to be tuned over?
(It seems like 8" diameter?)
 

·
Registered
Joined
·
92 Posts
Ok ok, well don’t take my question the wrong way. As my badge states, I’m a Noob... I was just wondering why you wouldn’t go sealed and shrink down the enclosure if space is an issue. I assume you are putting a strong amp to the pair.
 

·
Registered
Joined
·
77 Posts
Discussion Starter #14
I never really had plans of getting down to the recommended sealed volume with the plug/seal only, In fact, I will only get down to 2.3 ft^3 with a solid plug. I have absolutely no concerns with achieving the required structural integrity with the part that will replace the port, but do know that I won’t be able to reduce internal volume sufficiently with just the plug.

The thing is, once removed, the plug allows for the placement/securement of any variety of object that occupy volume. So it may take a bit more work when switching back and forth between sealed and ported, but that’s okay as I really don’t think it will be a common occurrence.

In WinSD it looked as if the larger sealed enclosure volumes resulted in more bottom end (albeit with the need of filters to prevent over excursion as the volumes increased dramatically) and it seemed like maximizing the volume for my available space didn’t have a downside while allowing for a ported alternate configuration.
You could use a PR in the plug.
What frequency is that port intended to be tuned over?
(It seems like 8" diameter?)
I would think that more than one 10” PR would be required? They are pretty foreign to me but I thought you need more PR displacement than the primary drivers? And at that point I’d had 2-3 drivers facing up that I would need to protect in my cargo area. Not gonna lie, it’s does sound cool but the port is in my hands already and should allow for tuning fun via length adjustments.

The port is nominally 5.9” ID bit flares out to 9.375” at the tip that mounts to the enclosure.. I don’t have my spreadsheet on hand but with the pieces I have I should be able to easily tune into the low 30’s without getting excessively long (20-23 inches depending on polyfill stuffing density).
 

·
Registered
Joined
·
77 Posts
Discussion Starter #15
Ok ok, well don’t take my question the wrong way. As my badge states, I’m a Noob... I was just wondering why you wouldn’t go sealed and shrink down the enclosure if space is an issue. I assume you are putting a strong amp to the pair.
No worries, newb here as well! Vertical height was my main restriction in terms of space. The goal was to not have the gear/enclosure be any higher than what the stock cargo floor height would be. The pair of 10w6’s will be driven by a JL HD1200/1.

The enclosure started as a vented only design with two slot ports that was approximately 2” longer than what I landed on. Pete from AudiDynamics designed the enclosure based on my subs/amp, listening goals (SQ) and available space/volume.

Changes to my amp rack and secondary battery position forced me to cut the length of the enclosure down by two inches, which resulted in a reduction in the internal volume and and increase in the tuning frequency (nominally 30.5 Hz) if the as designed vent length was maintained.

So I regrouped and came up with this plan. I cut all pieces by 2” and built the enclosure as you see it here with the plan of making it super modular so that I can have fun after the install. By going to the external port I was able to pretty much match the volume that Pete had designed for the original box, and with the single 5.9” ID flare I’m getting lower port velocities as well.

Should be interesting if nothing else!
 

·
Registered
Joined
·
92 Posts
Ok ok, well don’t take my question the wrong way. As my badge states, I’m a Noob... I was just wondering why you wouldn’t go sealed and shrink down the enclosure if space is an issue. I assume you are putting a strong amp to the pair.
No worries, newb here as well! Vertical height was my main restriction in terms of space. The goal was to not have the gear/enclosure be any higher than what the stock cargo floor height would be. The pair of 10w6’s will be driven by a JL HD1200/1.

The enclosure started as a vented only design with two slot ports that was approximately 2” longer than what I landed on. Pete from AudiDynamics designed the enclosure based on my subs/amp, listening goals (SQ) and available space/volume.

Changes to my amp rack and secondary battery position forced me to cut the length of the enclosure down by two inches, which resulted in a reduction in the internal volume and and increase in the tuning frequency (nominally 30.5 Hz) if the as designed vent length was maintained.

So I regrouped and came up with this plan. I cut all pieces by 2” and built the enclosure as you see it here with the plan of making it super modular so that I can have fun after the install. By going to the external port I was able to pretty much match the volume that Pete had designed for the original box, and with the single 5.9” ID flare I’m getting lower port velocities as well.

Should be interesting if nothing else!
Well that should be pretty awesome! I have the same HD1200 and (2) 10w6v3’s waiting to go into my minivan. Partially why I was interested.. I have a sealed enclosure for mine but I don’t need the trunk area much.. I hope the 10’s can get low enough where I’m not itching for a 12. I have a helix dsp3 to install also so I hope that helps
 

·
Premium Member
Joined
·
3,350 Posts
I would think that more than one 10” PR would be required? They are pretty foreign to me but I thought you need more PR displacement than the primary drivers? And at that point I’d had 2-3 drivers facing up that I would need to protect in my cargo area. Not gonna lie, it’s does sound cool but the port is in my hands already and should allow for tuning fun via length adjustments.

The port is nominally 5.9” ID bit flares out to 9.375” at the tip that mounts to the enclosure.. I don’t have my spreadsheet on hand but with the pieces I have I should be able to easily tune into the low 30’s without getting excessively long (20-23 inches depending on polyfill stuffing density).
A 12" earthquake SLAPS (long throw version) would likely work... they have some silly excursion... like 4". Maybe it would not be happy working laying down anyhow.

That port does have a bit of a statement to it.
It should knock the toupee off gramps in the back seat :cool:
At first I was a bit skeptical, but your arguement for an external port pretty much present a cogent plan.
So I kind of like it.

You may want the tuning freq lower, or use a sub sonic to prevent over excursion.

The idea of trombone adjustability reminds me of a Vtec like arraignment for intake tuning.
 
1 - 17 of 17 Posts
Top