Help Me with Custom Made 18"

[NEO Dan]

OK so what specs did you ask for and what box did you plan on putting it in?

 

[hawkson]

We asked for something with a high xmax and low hz, around 20.

The other user on the forum designed it with help of an engineer. It didn't come out right. I already paid for the 2 samples.

I don't have a box requirement. PPSL seems like the rage, but these 18" are big. Anything is good, probably will get the fp14000, also from china.

 

[NEO Dan]

Unless you re-cone with new soft parts that are much "softer" you will need to go sealed and use a LT circuit to boost the low end, it won't be efficient but you will get low bass.

New soft parts with different or fewer spiders would help you go lower with less boost but I would suspect it was done to increase durability.

If you inquire about the LG clones again please post the current pricing.

 

[hawkson]

The factory would like to know

“what are the dimensions of the cabinet"

What should i say? What are the ''''best''' dimensions? for a push push?

 

[Etocynned]

It sounds like the factory is asking how much cabinet space you are willing to give up in the room you are using.

eg 36x36x72 inches per cabinet one driver per cabinet.

which equald 54 cu ft.

however you need to determine the full thiele small parameters to get an optimal box with Optimus all up in your grill. The effects in that movie go down to 5hz if im not mistaken, the frequency where the human face separates from the skull at SPL's over 120db.

seems like you are in a sweet place to find a manufacturer to test the drivers and get a full set of specs, we cant really make a solid reccomendation without that.

 

[hawkson]

I thought the T/S specs were included with the diagrams i had on the first page?

 

[hawkson]

Any advice on size is appreciated.
thanks

 

[bjorno]

Any advice on size is appreciated.
thanks

Looking for home theater, clean and deep

The driver T/S you posted is suitable for a TH. If you want a sub that also provides 'clean' deep FR for music reproduction:IMO,You have to look for different T/S parameters and an entirely different enclosure type.

Here is an attempt to define new driver(T/S that are not extreme) for music use and in a T-TQWT (low organ notes without strain) that should be used together with ~50 Hz capable mains:


Now when I have control of both the Driver T/S and enclosure type:
No! I will not help to design a smaller box nor any other type of enclosures
unless the cut of frequency is changed to a number above 20 Hz

b

 

[nandababaji]

Any advice on size is appreciated.
thanks

I would go for a EBS (extended bass shelf) alignment to use those drivers in a 200L box tuned to 25Hz. Crossover at 80Hz, flat to 25Hz, f3 at around 22Hz. This will provide nice deep bass you can feel. The price you pay for this is efficiency around 84dB/watt as the EBS alignment trades efficiency for extended bandwidth. Need a nice large amp to drive them and you might add a 15Hz high pass filter to reduce excursion below 20Hz.

 

[bjorno]

... and you might add a 15Hz high pass filter to reduce excursion below 20Hz.

Hi, It looks like a ~30 Hz filter is more adequate if not the box is stuffed like a closed one + a small amount (~35 g) in the port as well.

b

 

[hawkson]

To be clear again
I have 2 (and can go up to 3) of these drivers sitting on the factory floor.
And they want me to tell them the size of the cabinet and arraignment that I'd like.

Thanks for the suggestions.

 

[hawkson]

I would go for a EBS (extended bass shelf) alignment to use those drivers in a 200L box (7 cubic feet) tuned to 25Hz. Crossover at 80Hz, flat to 25Hz, f3 at around 22Hz. This will provide nice deep bass you can feel. The price you pay for this is efficiency around 84dB/watt as the EBS alignment trades efficiency for extended bandwidth. Need a nice large amp to drive them and you might add a 15Hz high pass filter to reduce excursion below 20Hz.


What exactly are the cabinet dimensions you recommend?

 

[bjorno]

I would go for a EBS (extended bass shelf) alignment to use those drivers in a 200L box (7 cubic feet) tuned to 25Hz. Crossover at 80Hz, flat to 25Hz, f3 at around 22Hz. This will provide nice deep bass you can feel. The price you pay for this is efficiency around 84dB/watt as the EBS alignment trades efficiency for extended bandwidth. Need a nice large amp to drive them and you might add a 15Hz high pass filter to reduce excursion below 20Hz.


What exactly are the cabinet dimensions you recommend?

When using one driver:

http://www.diyaudio.com/forums/atta...-custom-made-18-hawk-18in_200l_ported_box.jpg

To tune exactly at 25 Hz : Half the amount of suggested stuffing in box and port. But it wont work with a 2 driver push-push configuration unless you double the box volume and port area as well.

b