Please help me design a PR subwoofer

[mike c]

the driver:
http://www.edesignaudio.com/product_...roducts_id=554

the PR:
18"
http://www.audiopulse.com/products/p...-radiators/vmp

additional data:
18" TC-VMP
Vap 0.0
Dia 390mm
Vas 0.0l
V-Fs 4Hz-24Hz
cms 0.0m/N
V-mms 500g-2500g

i'm aiming for it to act like a 17.6hz tuned ported subwoofer

questions:
1) anybody have specs on the 18" PR? i need QMS, Vas and Fs to be able to model with winisd. (winisd doesnt accept 0, what fs do I enter?
2) so the heavier i make the PR, the lower the tuning?
3) will enclosure volume change tuning? i mean, i can go bigger if it means making the box more efficient at being tuned low.
4) can i put both active and passive driver on the same baffle? (same side, making a tall tower all front firing)

[a1161979]

This had better be the begining of that Build thread im demanding Mike

Id love to help but im sure someone with more experience with passives will chime in and help, i take it you have you driver then Pictures please, how about one of your son sitting in it Although not while playing test tones like some idiot on the net (anyone else seen that?)

Come on guys get cracking and churn out some plans for the man

[mike c]

yep, this is the one

the active driver should arrive tomorrow.
the passive driver is more than a month away, but if people help me out, i dont think its necessary to wait for the passive driver before starting the box

[WmAx]

mike c wrote:

t
1) anybody have specs on the 18" PR? i need QMS, Vas and Fs to be able to model with winisd. (winisd doesnt accept 0, what fs do I enter?

Call Audiopulse/TC, they will provide you with the data that you require.

2) so the heavier i make the PR, the lower the tuning?

Yes.

3) will enclosure volume change tuning? i mean, i can go bigger if it means making the box more efficient at being tuned low.

Generally, as you decrease tuning frequency of the PR/port, you increase volume. If you decrease tuning frequency substantially and leave the volume fixed, you will have a highly dampened ported/PR system with a smooth and broad roll off that starts considerably higher into the band as compared to the tuning frequency of the port/PR.

4) can i put both active and passive driver on the same baffle? (same side, making a tall tower all front firing)

Yes.

-Chris

[mike c]

thanks Chris!

[mayhem13]

There are some excellent pr's available from funky waves that include the specs. i've got them loaded into Unibox already so if you're interested in using those instead-let me know and i'll model it for you. Just modeled at RLP-15 with 2 PR's and it modeled as well as ported in half the volume.

[mike c]

mayhem13 wrote:

There are some excellent pr's available from funky waves that include the specs. i've got them loaded into Unibox already so if you're interested in using those instead-let me know and i'll model it for you. Just modeled at RLP-15 with 2 PR's and it modeled as well as ported in half the volume.

thanks, but i dont have access to other PR's at the moment. funds have become really scarce

[mayhem13]

So you paid for the AP passives already but have to wait months to get them?

[mike c]

i only bought 1 AP passive (the other one was purchased by Financethi$ (jeff) )

and yes, i will get them in about a month++

[Mike P.]

Post pics when you get it. You'll be the first to get one, as far as I know. Looking forward to seeing what the beast looks like!

[mike c]

Mike P. wrote:

Post pics when you get it. You'll be the first to get one, as far as I know. Looking forward to seeing what the beast looks like!

the 13av.2 or PR?

the 13av.2 should arrive today ... expect a lot of pics!

[a1161979]

Expected... Still waiting... Do the deliverery men run on time over there? He had better today

Still cant wait to see that beast

By the way mike why the change from a small sealed sub? I would have though with the bottomless driver design and high travel it would have been perfect for a small sealed sub Watch the travel on those passives because that driver will really move some air... so yeah anyway why the change? I just love it that the Ed guys dropped a bridged EP2500 into it on the bench (in free air) and it wouldnt bottom The EP just fliped a fuse a few times and eventually went into protect mode Serious driver

Now go hunt down the poor delivery guy and get me those pictures

[mike c]

because i have sealed sub coming already

i wanted to build a ported sub for this one, but wasted a day designing a port (i use pen and paper btw) for box dimensions i did not want.

and for a sealed sub, i'd have to dedicate an EQ thingy for it to work properly too.
yes, when they promise a date, they shouldnt be off more than a day.

[a1161979]

Mike... Mike... Mike... You are still going to need an EQ regardless of the design

Ported, EBS, LLT, Passive, Sealed, Horn loaded it doesnt matter because none will perfectly intergrate with your listening environment

Eq is the most important aspect of any subwoofer HT, this is why velo, JL and other provide room eq sofware with their subwoofers. Are any of your other subs eq'ed, i though you allready had a BFD for all those subs of yours... Please tell me you have a BFD (been dying to use that smily)

[mike c]

a1161979 wrote:

Mike... Mike... Mike... You are still going to need an EQ regardless of the design

Ported, EBS, LLT, Passive, Sealed, Horn loaded it doesnt matter because none will perfectly intergrate with your listening environment

Eq is the most important aspect of any subwoofer HT, this is why velo, JL and other provide room eq sofware with their subwoofers. Are any of your other subs eq'ed, i though you allready had a BFD for all those subs of yours... Please tell me you have a BFD (been dying to use that smily)

i have two Velodyne SMS-1's (one for the pair of SVS ultras, one for my eD's and whatever I build now - if i went sealed, it would probably mess up my EQ due to the different tunings of my existing eDs, which is why i'm aiming for a DIY that will match a ported sub tuned to 17.6 hz)

and of course the DD18 has its own ...

[a1161979]

mike c wrote:

i have two Velodyne SMS-1's (one for the pair of SVS ultras, one for my eD's and whatever I build now - if i went sealed, it would probably mess up my EQ due to the different tunings of my existing eDs, which is why i'm aiming for a DIY that will match a ported sub tuned to 17.6 hz)

and of course the DD18 has its own ...

My understanding is that it is the interaction with the room not the design of the speaker (to an extent) I cant see why having a sealed and vented sub being EQ'ed through the same device as being a problem

Can someone correct me if im wrong but it seems silly your tuning your DIY sub at the specs of your ED's why do you want more output at that level anyway? I would be building the ED13av.2 sealed for 30-120Hz leaving the Ed's to run down into the bottom end

The 13av.2 in a smallish (.7qtc) should performe beautifully in the upper bass range, much better than the ED's anyway yet roll of enough to leave the Ed's to handle the extreme bottom end... Just thinking out aloud

[mike c]

a1161979 wrote:

My understanding is that it is the interaction with the room not the design of the speaker (to an extent) I cant see why having a sealed and vented sub being EQ'ed through the same device as being a problem

Can someone correct me if im wrong but it seems silly your tuning your DIY sub at the specs of your ED's why do you want more output at that level anyway? I would be building the ED13av.2 sealed for 30-120Hz leaving the Ed's to run down into the bottom end

The 13av.2 in a smallish (.7qtc) should performe beautifully in the upper bass range, much better than the ED's anyway yet roll of enough to leave the Ed's to handle the extreme bottom end... Just thinking out aloud

i've already tried splitting the signal previously, e.g. dual DLS-5000R's for 40-80hz and DD18 for 40hz and below.

i find that having similar subs playing the same signal in different locations in the room gives me better flexibility in placement.

also, you are correct that without EQ, a sealed 13av.2 in a .7Q box will only yield up 30+hz f3. i switch subwoofers a lot, and i can't afford a 'one trick' sub (e.g. on its own, its a midbass box without a low end boost)

btw, the 13av.2 is sitting in front of me ... but im at work its heavy.

[imbeaujp]

I am sure that you will enjoy your new passive radiator sub. Got two subs like that and it is a good compromise between scealed and ported. You got decent output and sound quality in a small pakage.

Yes you can place the passive radiator on the same side, you can put on any side except down fireing (some passive radiator can but not many of them, you got to see the specs to be sure).

[a1161979]

mike c wrote:

i've already tried splitting the signal previously, e.g. dual DLS-5000R's for 40-80hz and DD18 for 40hz and below.

i find that having similar subs playing the same signal in different locations in the room gives me better flexibility in placement.

also, you are correct that without EQ, a sealed 13av.2 in a .7Q box will only yield up 30+hz f3. i switch subwoofers a lot, and i can't afford a 'one trick' sub (e.g. on its own, its a midbass box without a low end boost)

btw, the 13av.2 is sitting in front of me ... but im at work its heavy.

Congrats mike thats one sick driver you have in you hands

Is it just me or are passives the in thing right now? Poor steve LLT is losing popularity

[mike c]

[mayhem13]

With the pr extension you're gonna have at extreme levels, you will have to put the PR's on opposing sides or the cabinet is gonna rock with the weighted movements. Your eD driver is capable of full extension of those PRs at 18 hz.

[Ricci]

I believe he's talking about using 1 PR and yes that is going to take a serious cabinet to keep that from walking around the room.

I like the looks of the 13av2 but man that is a fat surround that is really eating the cone area. Looks more like the cone of a 10".

[Mike P.]

The SD is listed as 556 cm^2, so it appears a lot of the surround is included as part of the cone area. Awesome looking subwoofer!

[mike c]

in lieu of exact specs of the PR. wild guess guys ... what size enclosure do i build for this driver and PR in CF ... let's say size of no consequence (maybe up to 10 cubes)