diy ALPINE dual subwoofer enclosure for home use

[mehrdadt63]

hi dears , im going to build dual subwoofer enclosure for home use , I am planning to build a ported box , considering that I have two subwoofers, how should I design the port so that it has the least noise?
subwoofers are dual Alpine hdz-110 and each 400 watt rms

Alpine HDZ-110 (11 inch)

Specifications

• Impedance: 2 Ohm + 2 Ohm
• Woofer diameter: 279mm
• Cut-out diameter: 251mm
• Mounting depth: 196mm
• Sensitivity 84dB SPL (2.83 V x2 @ 1 m)
• Frequency Response: 25Hz – 300Hz
• Recommended amplification: up to 200W / 2 Ohm RMS per channel

Thiele & Small Parameters:

• Re: 6.03 Ohm
• fs: 30.8 Hz
• Mms: 387.143 g
• Rms: 12.368 kg/s
• Cms: 0.069 mm/N
• BI: 29.491 N/A
• Qms: 6,048
• Qes: 0,519
• Qts: 0,478
• Vas: 48.9213 l
• Sd: 706.86 cm2

 

[somebodyelse]

Use a simulation package that shows you port air velocity, and keep it low to avoid chuffing. The larger the port area, the lower the velocity. How low depends on whether you have flared port ends, smooth joints and/or turns in the port etc. 10m/s is probably low enough if you have sharp transitions like an unflared port. If everything is smooth 30m/s might be ok. There's a worked example with WinISD here.

 

[mehrdadt63]

Use a simulation package that shows you port air velocity, and keep it low to avoid chuffing. The larger the port area, the lower the velocity. How low depends on whether you have flared port ends, smooth joints and/or turns in the port etc. 10m/s is probably low enough if you have sharp transitions like an unflared port. If everything is smooth 30m/s might be ok. There's a worked example with WinISD here.

god bless you bro ...

 

[Chrispy]

Why not build two subs ?

 

[DVDdoug]

Why not build two subs ?

That's not a bad suggestion. But with 2-Ohm woofers you'd probably have to wire them in series, which is "odd" for separate boxes.

Here's something I copied from Floyd Toole's book showing how 2 subs at different locations can help to smooth-out room resonances... And if you can't spread them out now, you can stack them (or set them side-by-side) and it will be about the same size as one dual-woofer sub but you can have more options in the future:

 

[mehrdadt63]

Why not build two subs ?

Because of furniture arrangement problem ...

 

[Flaesh]

Alpine HDZ-110 (11 inch)

• Sd: 706.86 cm2

Sd must be <500 cm2 for 11" driver. Are the other parameters correct?

p. s.: parameters are correct for Sd 706 cm2 and Re 6 ohm

 

[mehrdadt63]

Sd must be <500 cm2 for 11" driver. Are the other parameters correct?

p. s.: parameters are correct for Sd 706 cm2 and Re 6 ohm

is sd value wrong ? how is it posible an 11 inch subwoofer has such a high sd parametere ... maybe because of specific surround ?
It seems to have more of an advertising aspect, because even if we take the length of drivers front to back, it will still be less than these numbers
so is it kind of hurts when simulating subwoofer in WINISD ...

 

[Flaesh]

how is it posible

This is just a data set from another speaker.

 

[mehrdadt63]

This is just a data set from another speaker.

It is strange that the official Alpine websites write these numbers ... i send an email to alpine, if they answer.

 

[Flaesh]

t is strange that the official Alpine websites write these numbers

This is just sloppiness, carelessness, inattention and indifference (even if it is official). Also Re for 2+2 must be less than 4 ohms.
Of course, the data is not suitable for HDZ-110 modeling

 

[Flaesh]

Thiele & Small Parameters:

You can measure real TSP using REW. It's inexpensive and almost uncomplicated.
Even from the photo, one can assume a small equivalent volume. And the typical Q of such products is more than 0.5. Even a 50-liter box will require a monstrous port to tune to 20+ hertz.
I would make a closed box for these drivers.

p. s.: What size box can you afford considering the furniture arrangement?

 

[mehrdadt63]

You can measure real TSP using REW. It's inexpensive and almost uncomplicated.
Even from the photo, one can assume a small equivalent volume. And the typical Q of such products is more than 0.5. Even a 50-liter box will require a monstrous port to tune to 20+ hertz.
I would make a closed box for these drivers.

p. s.: What size box can you afford considering the furniture arrangement?

thank you bro
I was planning to use it for home theater, that's why I prefer ported ... other than that im so basshead one and seek deep bass
i was thinking around 150 litre for both of them....

 

[Flaesh]

seek deep bass

What is "deep"? 40 or 20 or 10 Hz?
I'm just a music lover, you can check out my thread on how subwoofers work. Link in signature.
Will you measure the actual parameters or will you get a letter from Alpine?))

 

[mehrdadt63]

In my opinion 20 hz at least 100 db is enough
Alpine didnt answer ... ok i will follow your link .
Thank a lot ...

 

[Wolf11Man]

Simple procedure is to measure TSP of your individual chassis, in the configuration you will use it later (voice coils in series or parallel). Resistance is part of TSP.
Next simulate. Now you get an idea.
Concerning port diameter. Flared ends will reduce chuffing to a great deal. Then, keep that in mind, the port velocity depends on your amp, nothing else. So when in theory, air speed will be too high at 2x600 Watt, but you only have 300W rms, you will never hit that mark.
Last, HT use is quite tollerant to port noise, the exploding house will be much more noise than a little chuff-chuff and it will nicely integrate into the tumbling rubble.

 

[mehrdadt63]

Simple procedure is to measure TSP of your individual chassis, in the configuration you will use it later (voice coils in series or parallel). Resistance is part of TSP.
Next simulate. Now you get an idea.
Concerning port diameter. Flared ends will reduce chuffing to a great deal. Then, keep that in mind, the port velocity depends on your amp, nothing else. So when in theory, air speed will be too high at 2x600 Watt, but you only have 300W rms, you will never hit that mark.
Last, HT use is quite tollerant to port noise, the exploding house will be much more noise than a little chuff-chuff and it will nicely integrate into the tumbling rubble.

You described it very well ... the reason could be that im going to a terrible search for finding best of possible , and that never happen.

 

[Wolf11Man]

Then you should learn the first rule of speaker building, "you always have to compromise".
There is no "best possible" to be found, not even close.
If you build a bass cabinet, this is even more true, as the final response is a product of speaker x room.

Looking at your chassis, I would concider selling them and get a not that heavy over souped pair to replace them.
For your cause they are so far away from "optimum" someone with your high standard should not even think about using them in room.

 

[mehrdadt63]

Then you should learn the first rule of speaker building, "you always have to compromise".
There is no "best possible" to be found, not even close.
If you build a bass cabinet, this is even more true, as the final response is a product of speaker x room.

Looking at your chassis, I would concider selling them and get a not that heavy over souped pair to replace them.
For your cause they are so far away from "optimum" someone with your high standard should not even think about using them in room.

I went for a relatively heavy driver , because I know that I won't be satisfied if I get a lighter one ... my expectation of sound is deep and hard hitting bass , other section of bands frequency not critical , i always listen to specific genre of music like psy , edm , ... by the way if you say that plan doesn't work so i should think more about it ...
that drivers ,.... i have a situation that can change them by a jl 12w7 If it makes a positive change.

 

[Flaesh]

can change them by a jl 12w7

Do it. 150 l box is enough for a pair. Use WinIsd or so.
Don't forget about the room's acoustics.
It's never too late to plug a hole .

p. s.: I listen to different music. For example, F. Dupré's "Ruins" is great at 110+ dB