Dayton 18" HO Ported Build Thread

[mikroland]

The sub finished.... except I'm contemplating a grill. Can't stand the waffle grills I used on my car subs when I was a kid... I"ll post more on the grill if I ever get around to making one. Also included one pic to show the interior bracing.....

Rob, would you be interested in building one of these for me and if so how much would you charge?

 

[lovinthehd]

Rob, would you be interested in building one of these for me and if so how much would you charge?

This is an old thread and Rob hasn't been on the forum for two and a half years or so....

 

[TLS Guy]

Rob, would you be interested in building one of these for me and if so how much would you charge?

If you really want one of those subs, why don't you go and see a cabinet maker with and CNC machine? You could ask them to make a flat pack for you or have them build it from the parts. If you want them to finish that might be spendy. Having it built locally will save you shipping which would be very costly.

 

[mikroland]

This is an old thread and Rob hasn't been on the forum for two and a half years or so....

Do you or anyone else here know where I can purchase a nice ported box for home theater to put one of these Dayton 18" drivers in?

If you really want one of those subs, why don't you go and see a cabinet maker with and CNC machine? You could ask them to make a flat pack for you or have them build it from the parts. If you want them to finish that might be spendy. Having it built locally will save you shipping which would be very costly.

Sounds like a good idea. Let me find out if I have a shop in my area that is capable and willing to do this.

 

[TLS Guy]

Do you or anyone else here know where I can purchase a nice ported box for home theater to put one of these Dayton 18" drivers in?


Sounds like a good idea. Let me find out if I have a shop in my area that is capable and willing to do this.

Let me know how you get on. Where are you located by the way?

 

[lovinthehd]

Do you or anyone else here know where I can purchase a nice ported box for home theater to put one of these Dayton 18" drivers in?


Sounds like a good idea. Let me find out if I have a shop in my area that is capable and willing to do this.

I don't know anyone who is providing flatpacks for a ported box for that driver. For a different driver (UM-18) there's some guys in southern California doing such that I know of with a different design. If you supply proper plans to someone qualified that could be a way to go. I take it you have no tools/inclination to do your own?

 

[mikroland]

Let me know how you get on. Where are you located by the way?

just north of New Orleans, LA.

I don't know anyone who is providing flatpacks for a ported box for that driver. For a different driver (UM-18) there's some guys in southern California doing such that I know of with a different design. If you supply proper plans to someone qualified that could be a way to go. I take it you have no tools/inclination to do your own?

I simply don't have the tools nor space to get it done. But I can definitely build a box.

By the way, what is the main difference between the UM-18 and the HO 18? I am looking to use one of these in a ported enclosure for H/T. I assumed the more expensive HO model would be the way to go. What do you guys think?

 

[lovinthehd]

just north of New Orleans, LA.


I simply don't have the tools nor space to get it done. But I can definitely build a box.

By the way, what is the main difference between the UM-18 and the HO 18? I am looking to use one of these in a ported enclosure for H/T. I assumed the more expensive HO model would be the way to go. What do you guys think?

Believe the UM-18 has lower response capabilities but been a while....they're both well regarded....just a bit different and have different box requirements.

 

[TLS Guy]

just north of New Orleans, LA.


I simply don't have the tools nor space to get it done. But I can definitely build a box.

By the way, what is the main difference between the UM-18 and the HO 18? I am looking to use one of these in a ported enclosure for H/T. I assumed the more expensive HO model would be the way to go. What do you guys think?

The HO 18 ported with my box is a far better and more potent sub. It also takes a lot less power and does not need Eq. The T/S parameters of that driver are right in the sweet spot for a ported or TL sub.

Members who have built it have been very pleased with it.

 

[lovinthehd]

The HO 18 ported with my box is a far better and more potent sub. It also takes a lot less power and does not need Eq. The T/S parameters of that driver are right in the sweet spot for a ported or TL sub.

Members who have built it have been very pleased with it.

Do you have measurements of a finished sub to share?

 

[TLS Guy]

Do you have measurements of a finished sub to share?

Do you have measurements of a finished sub to share?

Not that I have measured, because I have never built one. A member did measure one, but I don't remember who. The measurements agreed with the model. With a sub the model is very accurate, but I would never ever go to the bank with model of a speaker with crossovers.

The reason is that if the T/S parameters are honest, then the model will predict the final product pretty much exactly. That is why I will encourage building of a sub from a model, but only other designs under unique circumstances, like when a guy has the drivers, and I can make a reasonable stab at a viable solution.

 

[lovinthehd]

Not that I have measured, because I have never built one. A member did measure one, but I don't remember who. The measurements agreed with the model. With a sub the model is very accurate, but I would never ever go to the bank with model of a speaker with crossovers.

The reason is that if the T/S parameters are honest, then the model will predict the final product pretty much exactly. That is why I will encourage building of a sub from a model, but only other designs under unique circumstances, like when a guy has the drivers, and I can make a reasonable stab at a viable solution.

Hmmm not what I've read between modeling and built, particularly that phrase "exactly". I think it should definitely be modeled first, but.....

 

[TLS Guy]

Hmmm not what I've read between modeling and built, particularly that phrase "exactly". I think it should definitely be modeled first, but.....

The math is not complicated. The only thing that can drive you adrift is if the T/S parameters that are published are not correct.

The other issue is that measurements in room with a sub are not very accurate. They really need to be done outdoors. The measurements of a sub are going to be influenced by the room no matter how careful you are. It will measure differently room to room and by position in the room.

Lastly the UM-18 and the rest of that series are really optimal for sealed alignment, and not ported. The T/S parameters are less then ideal for ported. So that means a high F3 and the need for Eq, high pass filters and lots of power in a sealed box. The HO -18 beats the UM-18 in a ported box by a mile and will have the much better quality bass.

The only advantage of a sealed box is smaller volume. If space is not at a premium then going for a non sealed alignment with a lower Q driver is the way to go every time. That is because a speaker cone alone is a terrible coupler to the air. In the bass an acoustic transformer to convert air pressure to air displacement is required. That means a Helmholtz resonator, a pipe or a horn.

 

[lovinthehd]

The math is not complicated. The only thing that can drive you adrift is if the T/S parameters that are published are not correct.

The other issue is that measurements in room with a sub are not very accurate. They really need to be done outdoors. The measurements of a sub are going to be influenced by the room no matter how careful you are. It will measure differently room to room and by position in the room.

Lastly the UM-18 and the rest of that series are really optimal for sealed alignment, and not ported. The T/S parameters are less then ideal for ported. So that means a high F3 and the need for Eq, high pass filters and lots of power in a sealed box. The HO -18 beats the UM-18 in a ported box by a mile and will have the much better quality bass.

The only advantage of a sealed box is smaller volume. If space is not at a premium then going for a non sealed alignment with a lower Q driver is the way to go every time. That is because a speaker cone alone is a terrible coupler to the air. In the bass an acoustic transformer to convert air pressure to air displacement is required. That means a Helmholtz resonator, a pipe or a horn.

I was thinking more about variances of the box build to an extent than the math, plus T/S parameter variances. I wasn't suggesting indoor measurements either. What does "beats by a mile" mean in this instance?

 

[TLS Guy]

I was thinking more about variances of the box build to an extent than the math, plus T/S parameter variances. I wasn't suggesting indoor measurements either. What does "beats by a mile" mean in this instance?

Well you get greater output for far less power and with a low Q driver.

We have gone over the ground and limitation of sealed subs again and again. Basically it all come down to Hoffman's iron law. However you choose to reduce the size of a sub you pay a penalty in terms of efficiency and low bass output.

In addition if you choose a nice low Q driver, then F3 will be so high you run out of xmax before getting high output in the last octave.

The ONLY reason for a sealed sub is smaller box volume, after that it is all down hill.

 

[lovinthehd]

Well you get greater output for far less power and with a low Q driver.

We have gone over the ground and limitation of sealed subs again and again. Basically it all come down to Hoffman's iron law. However you choose to reduce the size of a sub you pay a penalty in terms of efficiency and low bass output.

In addition if you choose a nice low Q driver, then F3 will be so high you run out of xmax before getting high output in the last octave.

The ONLY reason for a sealed sub is smaller box volume, after that it is all down hill.

Can you be more specific about the greater output....at what frequencies and also regardless of power for example, What system q are you comparing at?

 

[mikroland]

The is a far better and more potent sub. It also takes a lot less power and does not need Eq. The T/S parameters of that driver are right in the sweet spot for a ported or TL sub.

Members who have built it have been very pleased with it.

Cool, so the tuning frequency of this box is 19.05 Hz?

Do you happen to have any box plans for this setup?

 

[Kingnoob]

Can you be more specific about the greater output....at what frequencies and also regardless of power for example, What system q are you comparing at?

Yeah lots of pre built subs sealed have too small cubic foo ones made by subwoofer companies!!!


Ultimate bass lover !! si ht15 dvc.
Free the reptile aliens

 

[bassbear]

Well you get greater output for far less power and with a low Q driver.

We have gone over the ground and limitation of sealed subs again and again. Basically it all come down to Hoffman's iron law. However you choose to reduce the size of a sub you pay a penalty in terms of efficiency and low bass output.

In addition if you choose a nice low Q driver, then F3 will be so high you run out of xmax before getting high output in the last octave.

The ONLY reason for a sealed sub is smaller box volume, after that it is all down hill.

Hello,
I have noticed that ts parameters of the driver currently sold (available in the shops) are different than the parameters attached to pdf in the first post (e.g. fs 19.5 vs 18.8, vas 297.9 liters vs 272 etc.). Are this measurments still valid?

 

[TLS Guy]

Hello,
I have noticed that ts parameters of the driver currently sold (available in the shops) are different than the parameters attached to pdf in the first post (e.g. fs 19.5 vs 18.8, vas 297.9 liters vs 272 etc.). Are this measurments still valid?

I did not know that the driver parameters had changed. When did that happen? I will have to remodel the design with the new numbers, but I doubt it will change significantly.