annunaki

annunaki

Moderator
MDF is cheap. But, how much will the rest of the bits cost - ballpark?
The drivers I picked up for $75 each

The Plate amp was about $110.00 (Bash 300 Watt)

The EQ was about $100.00 (feedback destroyer)

Mineral Wool $11.00 or so.
 
GO-NAD!

GO-NAD!

Audioholic Spartan
The drivers I picked up for $75 each

The Plate amp was about $110.00 (Bash 300 Watt)

The EQ was about $100.00 (feedback destroyer)

Mineral Wool $11.00 or so.
I would actually need a design that would fit between studs, as it would have to go into a load-bearing wall. The concept is quite interesting though and more economical than I would've thought. I assume the feedback destroyer is there to compensate for the placement of the subwoofer and the fact that it can't be moved to an optimal position? The drivers - are they all the same as the ones used in cars?
 
gercho

gercho

Audioholic Intern
The drivers I picked up for $75 each

The Plate amp was about $110.00 (Bash 300 Watt)

The EQ was about $100.00 (feedback destroyer)

Mineral Wool $11.00 or so.
Would you be posting more pics of the finished project? It's very interesting.
 
annunaki

annunaki

Moderator
I would actually need a design that would fit between studs, as it would have to go into a load-bearing wall. The concept is quite interesting though and more economical than I would've thought. I assume the feedback destroyer is there to compensate for the placement of the subwoofer and the fact that it can't be moved to an optimal position? The drivers - are they all the same as the ones used in cars?
The drivers are the same as what is used in the car.
You are correct about the BFD.

The standard wall cavity is about 1.71ft^3 gross volume floor to ceiling (bracing & vent displacement have to be subtracted). The problem is the minuscule 2.5" of internal depth within the enclosure. To accommodate the 8W1v2 one must thicken the baffle by 1/2" - 5/8". The nice part about doing such is that it flushes with the drywall on the exterior.

The W1v2 drivers are well suited to this application due to their patented cooling design, (i.e. they have no rear pole vent) which allows close placement to an enclosure wall.

If you are seriously considering such a design, I can help you out.
 
GO-NAD!

GO-NAD!

Audioholic Spartan
The drivers are the same as what is used in the car.
You are correct about the BFD.

The standard wall cavity is about 1.71ft^3 gross volume floor to ceiling (bracing & vent displacement have to be subtracted). The problem is the minuscule 2.5" of internal depth within the enclosure. To accommodate the 8W1v2 one must thicken the baffle by 1/2" - 5/8". The nice part about doing such is that it flushes with the drywall on the exterior.

The W1v2 drivers are well suited to this application due to their patented cooling design, (i.e. they have no rear pole vent) which allows close placement to an enclosure wall.

If you are seriously considering such a design, I can help you out.
I am serious, but it can't happen in the short term, as I have too many irons in the fire as it is. But, next year, it might be possible. I have to make sure wifey is on board first though. She would appreciate getting a sub off the floor, but she'd also consider a new one as a waste of money. I'll have to find out what she dislikes more - spending a few hundred dollars on another sub or having the present one "in the way".
 
annunaki

annunaki

Moderator
Here are a couple of more "finished" pics.

The finish work of the room is nearly completed. I will be installing the drivers and firing everything up sometime in the next month (or two) or so.



 
GO-NAD!

GO-NAD!

Audioholic Spartan
I check in occasionally to see how it's progressing - looks great! I have a couple of questions. The amplifier - where does it go? Is it a separate component? Somehow, I was expecting it to be built in with the sub. And, why did you go with a vertical orientation of the drivers and the vent? Does it make a difference?

If I were to consider such an installation, I'd be compelled to, at the very least, have the vent in a much lower position. Also, it would be for music only, as part of a 2.1 system. So, would I be able to get the performance I'd like from a smaller package? A -3 dB point of 30 Hz, or maybe 27 Hz at the very lowest would be sufficient - would you agree? Out of a collection of 450+ Cds, I have precisely one of pipe organ music. :) So, even the numbers I mentioned could be overkill.
 
annunaki

annunaki

Moderator
The design was to minimize bends in the vent, as well as have everything fit behind one simple snap on grill. I cant exactly have the woofers sitting in the port. ;)

Achieving -3db at 30hz is no sweat with a well executed in-wall design. This one is-3db at 23hz at 108 db anechoic according to my modeling. Vent velocity is in the 15m/s range with 1.5x recommended power.

A single 8" or doing a pair of them (in two separate floor to ceiling cavities) can yield nearly the same result.
 
GO-NAD!

GO-NAD!

Audioholic Spartan
The design was to minimize bends in the vent, as well as have everything fit behind one simple snap on grill. I cant exactly have the woofers sitting in the port. ;)

Achieving -3db at 30hz is no sweat with a well executed in-wall design. This one is-3db at 23hz at 108 db anechoic according to my modeling. Vent velocity is in the 15m/s range with 1.5x recommended power.

A single 8" or doing a pair of them (in two separate floor to ceiling cavities) can yield nearly the same result.
I guess I didn't phrase my question clearly. By positioning the vent lower, I mean could you rotate the whole installation (drivers and port) to horizontal. Or, could the vent be moved down deside the drivers, while remaining vertical. Would such configurations affect the performance?

I have a large space: living room adjoining dining room, adjoining kitchen in a "U" shaped configuration, with the basement stairwell inside the "U". The 3 rooms add up to over 3000 cubic feet. I don't need to hear the sub in the kitchen, but I assume that the total airspace will "bleed" the sound pressure from the living room? If so, would a dual design be needed to get a healthy volume and a relatively flat FR down to 30Hz in the living room?

The length of your port looks to be more than the normal 14 1/2" space found between studs. For a design that would have a higher -3 dB point, I assume the port length could be reduced so that it could have a horizontal orientation to fit between studs? A big factor for me, would be how unobtrusive I could make an in-wall sub. Less visibilty means better chance of approval from head office.;)
 
S

speakEZ

Audioholic
Annunaki sorry if I missed it, but where are the wires? The receiver going to be in the living room?

Intuitive build by the way. I bet it will sound great!
 
annunaki

annunaki

Moderator
The wire runs to a closet where all of the equipment, including the plate amp, will reside. Everything is controlled via IR or RF.

The only things visible will be the TV and speaker grilles.
 
annunaki

annunaki

Moderator
I guess I didn't phrase my question clearly. By positioning the vent lower, I mean could you rotate the whole installation (drivers and port) to horizontal. Or, could the vent be moved down deside the drivers, while remaining vertical. Would such configurations affect the performance?

I have a large space: living room adjoining dining room, adjoining kitchen in a "U" shaped configuration, with the basement stairwell inside the "U". The 3 rooms add up to over 3000 cubic feet. I don't need to hear the sub in the kitchen, but I assume that the total airspace will "bleed" the sound pressure from the living room? If so, would a dual design be needed to get a healthy volume and a relatively flat FR down to 30Hz in the living room?

The length of your port looks to be more than the normal 14 1/2" space found between studs. For a design that would have a higher -3 dB point, I assume the port length could be reduced so that it could have a horizontal orientation to fit between studs? A big factor for me, would be how unobtrusive I could make an in-wall sub. Less visibilty means better chance of approval from head office.;)
I knew exactly what you are referencing.

I would need to see some pictures of you room or a design layout to see what placement options you may have.

There are not many different vent placement options when one has such a small enclosure volume to work with. You may need to look into a vent on top horizontally placed with the woofer(s) at the bottom. I will check

In this design I did for my friend, I had more options for vent placement due to the size of the enclosure. Now, depending upon your basement, one could also do an in-floor sub that fires up through a vent somewhere?
 
GO-NAD!

GO-NAD!

Audioholic Spartan
I knew exactly what you are referencing.

I would need to see some pictures of you room or a design layout to see what placement options you may have.

There are not many different vent placement options when one has such a small enclosure volume to work with. You may need to look into a vent on top horizontally placed with the woofer(s) at the bottom. I will check

In this design I did for my friend, I had more options for vent placement due to the size of the enclosure. Now, depending upon your basement, one could also do an in-floor sub that fires up through a vent somewhere?
Here is a photo of my living room (well, at least part of it...). It's not a great photo for getting an idea of the layout, so I can take more if you need them. You can see my components stacked in the left corner. Somewhere on that left side wall, is where I'd consider placing a sub, preferably right behind the component stack. I will be building a component stand this fall and it will be placed directly opposite the present location.

I think I'm limited to installing a sub in that left side wall because the other two walls are exterior. It's brick construction and the exterior wall cavities are only 2" deep. That interior wall is normal 2" x 4". There isn't a usable wall opposite the fireplace, as it opens up to the hallway and the dining room

I think you will understand my need to implement some form EQ into the system, because of the speaker placement. Acoustic panels and moving the speakers are not options for me.:( Since we're talking 2.1 and I don't have any crossover, would I need a CX2310 in addition to the BFD, or would the DCX2496 do everything I need? To be quite honest, I don't understand the difference between the DCX and the BFD, other than the crossover in the DCX. Do they accomplish the same task by different means, or do they serve two different functions all together?:confused:

Putting a sub in the floor is physically possible, as the furnace room/workshop is directly below, but I do not see it as an option that will meet with approval. It would probably be the easiest to install, as there would be no drywall to mess with and there would be lots of room for the enclosure. If you had some photos of an in-floor sub, I would be able to get an idea of the WAF.

Thanks for entertaining my inquiries, as I would really like to do this. I just need to get my justification ducks in a row.:)
 
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GO-NAD!

GO-NAD!

Audioholic Spartan
I just thought of something - how about an in-ceiling sub? Would that work? Placement would be more flexible and the attic is above, giving me free access. I could get white grill cloth and it would blend right in!
 
H

Highbar

Senior Audioholic
I just thought of something - how about an in-ceiling sub? Would that work? Placement would be more flexible and the attic is above, giving me free access. I could get white grill cloth and it would blend right in!
If you google "infinite baffle subwoofer" you will find a bunch of ideas on infloor/ceiling subs. Like you said in the ceiling you could cover it with grill cloth in the floor it could be as simple as covering it with a register vent that would be used with a/c-heating. Either way you wont see much of anything.
 
annunaki

annunaki

Moderator
Here is a photo of my living room (well, at least part of it...). It's not a great photo for getting an idea of the layout, so I can take more if you need them. You can see my components stacked in the left corner. Somewhere on that left side wall, is where I'd consider placing a sub, preferably right behind the component stack. I will be building a component stand this fall and it will be placed directly opposite the present location.

I think I'm limited to installing a sub in that left side wall because the other two walls are exterior. It's brick construction and the exterior wall cavities are only 2" deep. That interior wall is normal 2" x 4". There isn't a usable wall opposite the fireplace, as it opens up to the hallway and the dining room

I think you will understand my need to implement some form EQ into the system, because of the speaker placement. Acoustic panels and moving the speakers are not options for me.:( Since we're talking 2.1 and I don't have any crossover, would I need a CX2310 in addition to the BFD, or would the DCX2496 do everything I need? To be quite honest, I don't understand the difference between the DCX and the BFD, other than the crossover in the DCX. Do they accomplish the same task by different means, or do they serve two different functions all together?:confused:

Putting a sub in the floor is physically possible, as the furnace room/workshop is directly below, but I do not see it as an option that will meet with approval. It would probably be the easiest to install, as there would be no drywall to mess with and there would be lots of room for the enclosure. If you had some photos of an in-floor sub, I would be able to get an idea of the WAF.

Thanks for entertaining my inquiries, as I would really like to do this. I just need to get my justification ducks in a row.:)
The DCX would allow for superb integration of your mains and the sub, especially if they (mains) are powered by an outboard amplifier. The DCX is like having the crossover and the BFD in one enclosure with both of them on steroids. The DCX will allow for infinitely adjustable crossover points & slopes, along with infinitely adjustable frequency shaping allowing boost, cut, and 'Q' adjustment at any of those frequencies.

One can also set infrasonic, lowpass, highpass or bandpass filters for proper integration of most any system.
 
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