Is there interest in a large three way "monkey coffin" collaboration?

[lorenmjones]

So this is an offshoot from that thread I thread jacked so I moved here in the interest of giving back the OP's thread.

So it seems like this question about a big loud full range with some nostalgia in the form factor gets asked a lot and the main replies are Zaph's SB 3 way from Madisound and the Tarkus. Both are obviously great designs but it seems there is some fair degree of interest in the form factor of something like Zaph's SB design but at a lower price point. There are a zillion stand mount two ways and smaller three ways but not a lot of big three ways with 12" woofers around.

I would suggest that with some collaboration we could come up with a design for around $400 in parts that would use value oriented drivers wisely implemented to come up with a design that would meet these criteria.

1) LF extension with F3 in the 20's. So vented cabinet is needed, and in many rooms this would give some emphasis in the lowest octave. Perhaps a sealed option could be part of it but I'd favor vented overall. Perhaps small box vented with low tuning would be a nice middle of the road solution

2). Smooth and flat FR with fairly smooth polars.

3). Some attention to diffraction and boundary reinforcement in the design regarding woofer distance from floor, placement of mids and tweeters relative to baffle edges.

So who would be interested in participating in a collaborative build effort?

[isaeagle4031]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Count me in.

[djg]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Perhaps something that could be on the floor, up against the wall, or at least a voicing option for that, like in the old days. Lattice grill and raised baffle edge optional.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

We are all aware that you know the ins and outs of large three way's. Experience welcome.

Count me in.

[andy19191]

Re: Is there interest in a large three way "monkey coffin" collaboration?

1) LF extension with F3 in the 20's. So vented cabinet is needed, and in many rooms this would give some emphasis in the lowest octave. Perhaps a sealed option could be part of it but I'd favor vented overall. Perhaps small box vented with low tuning would be a nice middle of the road solution

This looks like ruling out nice efficiencies in order to be better for films? In the 30s and possibly even 40s would seem more in line with big and loud without being overly intrusive for music. This is not to say an F3 in the 20s should not be the target but it will push the design in a particular direction.

[rpb]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I enjoy x-over sims, so I'm up for that part.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I think a reduced baffle step compensation version would be a great option. Also yet to be explored obviously would be the specifics of the low-frequency enclosure alignment.

Perhaps something that could be on the floor, up against the wall, or at least a voicing option for that, like in the old days. Lattice grill and raised baffle edge optional.

[rpb]

Re: Is there interest in a large three way "monkey coffin" collaboration?

This looks like ruling out nice efficiencies in order to be better for films? In the 30s and possibly even 40s would seem more in line with big and loud without being overly intrusive for music. This is not to say an F3 in the 20s should not be the target but it will push the design in a particular direction.

The room and speaker location play a large roll in bass response. If the design has sufficient sensitivity from the mid(s) and tweeter, perhaps the design could be used with various woofers and BSC. One of the 3-ways I made for a center had the woofer close to the floor. My mid, which had the same 90 dB sensitivity was not loud enough to get the tonal balance right. So, I think we might potentially need about 6 dB more output from the mids, and tweeter, than the woofer has at 100 hz. Then we make adjustable padding to bring them down as needed. The best way to know how much is to adjust by ear.

[gdmoore28]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I don't have the technical expertise to help guide this build in any way or fashion, but I will be following it closely. I'm a fan of large woofers instead of sat/subs, and have been focusing most of my building in that area. I don't listen to home theater at all, so music is my only focus, but it just seems to me that the best music reproduction is produced by large woofs, while HT is best served by the sat/sub formula simply because of space considerations.

Anyway, thanks for starting this thread. I hope there are lots and lots of big woof fans left out there. And the $400 target cost is a big plus, as I believe that is probably the range that most builders of these systems shoot for.

GeeDeeEmm

[isaeagle4031]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Depending on the woofer crossover point and baffle width, there will probably be very little need for BSC. A 12 or maybe 15, will have enough output that baffle step becomes a non issue. The series 2 as well as a couple of drivers at mcm. The price point won't be easy, but I still think is done doable.

[Sydney]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I think a reduced baffle step compensation version would be a great option. ....

I saw a thread from 2007 in which the OP was installing variable BSC.
Seen the circuits - haven't tried it.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

I think we can still end up at 89 db and get that sort of LF extension. More and more music has deeper LF content IMO.

This looks like ruling out nice efficiencies in order to be better for films? In the 30s and possibly even 40s would seem more in line with big and loud without being overly intrusive for music. This is not to say an F3 in the 20s should not be the target but it will push the design in a particular direction.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

If I had the technical skills I would do it myself. But I know I'm lacking in that. I think $400 in parts is enough to stay out of goldwood woofers, piezo tweeters and sealed back mids but not so much to dissuade many folks interested in a design like this.

I don't have the technical expertise to help guide this build in any way or fashion, but I will be following it closely. I'm a fan of large woofers instead of sat/subs, and have been focusing most of my building in that area. I don't listen to home theater at all, so music is my only focus, but it just seems to me that the best music reproduction is produced by large woofs, while HT is best served by the sat/sub formula simply because of space considerations.

Anyway, thanks for starting this thread. I hope there are lots and lots of big woof fans left out there. And the $400 target cost is a big plus, as I believe that is probably the range that most builders of these systems shoot for.

GeeDeeEmm

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

So with a 14" to 16" baffle width the F3 of baffle loss would be in the lower 300's right. That would work ok with a single mid of similar sensitivity to the woofer?

I had in mind DCS305, a pair of SB13 mids and a Vifa BC25 or Dayton ND25. Dayton RS150P might be nice too. Or a Faital Pro 6FE200 for the mid. That woofer will reach 20's vented in 3 to 4 CF and is affordable. Any thoughts?

Depending on the woofer crossover point and baffle width, there will probably be very little need for BSC. A 12 or maybe 15, will have enough output that baffle step becomes a non issue. The series 2 as well as a couple of drivers at mcm. The price point won't be easy, but I still think is done doable.

[lorenmjones]

Re: Is there interest in a large three way "monkey coffin" collaboration?

Interesting point. What does everyone think?

Thanks Kim for crossover sim help.

The room and speaker location play a large roll in bass response. If the design has sufficient sensitivity from the mid(s) and tweeter, perhaps the design could be used with various woofers and BSC. One of the 3-ways I made for a center had the woofer close to the floor. My mid, which had the same 90 dB sensitivity was not loud enough to get the tonal balance right. So, I think we might potentially need about 6 dB more output from the mids, and tweeter, than the woofer has at 100 hz. Then we make adjustable padding to bring them down as needed. The best way to know how much is to adjust by ear.