Filling a missing niche in accomplished designs

[Hdale85]

But the RS driver have been used in so many projects. And the cost difference doesn't change much as a RS driver will have a more complex crossover and therefor cost more money while the W4 has a less expensive xo. So it would about equal out. And besides the W4 is so sexy :B

[NateTTU]

I'm currently planning on building the statements and was in the need for surrounds. A MT version using the W4 and CD1 or possibly CD3 is my vote. I bet these would blend in so well.

[Jed]

I also agree with this, plus the RS drivers cost less.

I'm thinking of using the RS125 in the MMTMMW speaker. As for using the RS125 in an MT and MTM, I'd recommend Roman's microbe design which is a well documented speaker. I also wouldn't recommend the RS125 crossed much higher than 2-2.5k LR4, so that would not work well with the ribbon tweeter.

That said, I think it is important to explore some new turf too. I haven't ordered any drivers yet so lets keep the discussion open. This way, we can all be on the same page and see why certain decisions were made. For example, the CD1 tweeter is a good fit for an MT, but not the MTM for reasons documented above.

The RS150, although good performing up to 1.5k, will not be as close with CTC spacing in a 2.5way mmtmm format, which might suggest using the RS125 in such a design. Plus there are already great MTM and MT designs using the RS150. If someone has a really good argument, like using the RS150 in an MMTMM will negate the necesity of a sidefiring woofer, then we'll entertain that idea when the time comes.

This has been a lot of fun for me to see if we can gather the DIY community and really decide on a form factor that will work for a lot of folks. Voice your opinions, be heard, and who knows, it might be a speaker finished in a few weeks.

[Hdale85]

I think the CD1 and W4 are good for the MT.

MTM D26 and W4.

MMTMM I would say go with RS125 or 150 as they are cheaper and what not and thats a lot of driver to be buying As for tweeter....Probably the D26 or the Seas.

[dlneubec]

You've seen some conventional uses for the RS drivers, but about the only unconventional stuff I can recall has been the omni stuff I have been doing.

I'm interested in a surround speaker with both some direct and ambient sound qualities, as I have posted before. How about an RS open baffle dipole? Mini line array? Bipole? Open back/TL mid? TL tower?

As mentioned, not much in the MMTMM has been done with them.

Personally, having measured and listened to both the RS150 and RS125, and seen the distortion measurments, I would go for the RS150 despite the fact that it removes ribbon tweeters from the mix. There are lots of ribbon tweeter designs around also. Just my opinion. :B

[PoorboyMike]

How did Jim get away with the ribbon in the Statements, which use an MTM configuration? I thought I recalled him saying that with ribbons, you measure to the edge of it, rather than the middle like a typical dome tweeter. If that is the case, why couldn't the CD1 be used with the W4 in an MTM configuration?

IMO, it wouldn't make much sense to do a ribbon tweetered MT and a dome tweeter MTM. Maybe I'm wrong, but it doesn't seem like they would match up very well together.

[cobbpa]

I'm surprised a little at the direction this project is headed...no love for the RS52! Jed, I thought you would be campaigning to use it, you seemed pretty impressed by it. I guess the better low extension of the TB gives it the nod? Doesn't the dome have better distortion figures across much of the used range?

[---k---]

Boy this thread moved fast while I was gone today. I would be interested in seeing a project using the Seas 29TFF/W (H1318) Fabric dome with the semi-waveguide.
http://www.madisound.com/catalog/product_info.php?cPath=45_229_270_324&products_id= 1591

[---k---]

And, I would still like to see something cheep and not using the RS drivers (paper?) that I could build just for the fun of it and compare to my project and some of the other plentiful RS project. But, hey it's your project.

[Jim Holtz]

I thought I recalled him saying that with ribbons, you measure to the edge of it, rather than the middle like a typical dome tweeter.

That is correct for CTC calculations per Jim Griffin. It's how the Statements use a 3750 Hz. crossover with perfect driver integration too.

Jim

[Dennis H]

thought I recalled him saying that with ribbons, you measure to the edge of it, rather than the middle like a typical dome tweeter.

Actually, the important dimension is M-M. Center to center or, if you're anal, far edge to far edge, should be less than a wavelength for the best vertical dispersion. That's not saying speakers that violate that can't sound good of course.

[nayr]

I'd love to see a tiny MTM with a ribbon tweeter and 3" or 4" drivers

[sprint_9]

I'm thinking of using the RS125 in the MMTMMW speaker. As for using the RS125 in an MT and MTM, I'd recommend Roman's microbe design which is a well documented speaker. I also wouldn't recommend the RS125 crossed much higher than 2-2.5k LR4, so that would not work well with the ribbon tweeter.

That said, I think it is important to explore some new turf too. I haven't ordered any drivers yet so lets keep the discussion open. This way, we can all be on the same page and see why certain decisions were made. For example, the CD1 tweeter is a good fit for an MT, but not the MTM for reasons documented above.

The RS150, although good performing up to 1.5k, will not be as close with CTC spacing in a 2.5way mmtmm format, which might suggest using the RS125 in such a design. Plus there are already great MTM and MT designs using the RS150. If someone has a really good argument, like using the RS150 in an MMTMM will negate the necesity of a sidefiring woofer, then we'll entertain that idea when the time comes.

This has been a lot of fun for me to see if we can gather the DIY community and really decide on a form factor that will work for a lot of folks. Voice your opinions, be heard, and who knows, it might be a speaker finished in a few weeks.

Yea it would be cool to use the RS125 as it hasnt been used much like you said in your first post starting the thread.

CJD mentioned he is working on a 2.5 way center earlier on perhaps when the time comes if it comes that you start on the MMTMM(W) design that a uniformaty between drivers could be maintained so everything matches well for a home theather arrangement. Im not so much concerned with the woofers as he is using the RS150, the 125 would match decently, or the 150 if we go that route in the tower. But more so on the tweeter, I dont know what will happen there but it would be nice to use the same throughout.

On the side woofer I had personally kind of planned to use a RS HF 12 inch in a sealed box with an active sub amp, but a passive woofer would also work good aswell. These are my thoughts and I just wanted to get them out there as I would be very interested in a system like this, I hope also that I havent stepped on any toes or imposed in any way.

[sprint_9]

I would also like to add that I am excited to see the small TB MT progress. I think it would make a killer small surround to the Statements or Mini Statements.

[Jed]

IMO, it wouldn't make much sense to do a ribbon tweetered MT and a dome tweeter MTM. Maybe I'm wrong, but it doesn't seem like they would match up very well together.

Good point. Looks like a lot of people want the ribbon design, even if CTC in an MTM isn't as close as it could/should be with the ribbon's limitation of a relatively high crossover point.

I'll add, if we can afford to go with Fountek CD3.0 it is a bit more versatile (MTM) than the CD1.0 if specs are believed. Kinda increases the price a lot though.

[Hdale85]

Well since it looks like you'll be ordering the ribbons anyways you could do a test baffle make some measurements and see how it goes? Just an idea if not workable your not losing any money.

[Jed]

Jed, I thought you would be campaigning to use it, you seemed pretty impressed by it. I guess the better low extension of the TB gives it the nod? Doesn't the dome have better distortion figures across much of the used range?

I'm trying to stay pretty neutral and see what people really want, and yes the RS52 is an awesome performer and I love it in my GMK7 design. People are welcome to use that design if they feel so inclined- hey it uses a paper cone too guys! The ER18RNX. https://www.htguide.com/forum/showpo...&postcount=371

And your assessment of the TB is correct in regards to its useage in a Fullrange, and MT or MTM layout. Rs52 has much more limited bandwidth.

[Jed]

Ok, as it appears from all the posts people seem to dig the idea of the following drivers.

TB W4, Fountek CD1.0 MT
TB W4, Fountek CD1.0 MTM to match above
TB W4 Full range minispeaker


TB W4, Vifa D26 Center horizontal MTM, I can try the Fountek CD1.0 in a center configuration, but if I get weird lobing cancelations I'll have to resort to a dome tweeter for a lower crossover point or try something innovative with driver layout. If you have ideas let me know.

[Hdale85]

Like I said if the Fountek doesn't work in the MTM just go with the D26. They are going to be very small MTM's so could easily be used as surround duty as well as center and mains.

[Jed]

Like I said if the Fountek doesn't work in the MTM just go with the D26. They are going to be very small MTM's so could easily be used as surround duty as well as center and mains.

I get this feeling I'll be doing 2 versions, one with the ribbon and one with the Vifa, for all the designs. I'll probably shoot myself for saying this.

[Hdale85]

Hmm....yeah you might? Starting to bite off more then you can chew? By all means don't kill your self on our account. No reason you can't put your foot down a little After all you are the designer.

[Jed]

Hmm....yeah you might? Starting to bite off more then you can chew? By all means don't kill your self on our account. No reason you can't put your foot down a little After all you are the designer.

Well, you all discuss the tweeter options a bit more, I gotta get some rest before my flight back to Rochester. When I get back I'll probably order up some parts and then get started on the construction.

[Johnloudb]

NeoCd3.0M

I would also like to add that I am excited to see the small TB MT progress. I think it would make a killer small surround to the Statements or Mini Statements.

I like!!! If the Statements use the NeoCd3.0M, Maybe, you could use that in the MTM instead of CD1. It would work better in an MTM and complete the home theater system.

Use the CD1 in the MT for rear channels or just nice (inexpensive) stereo speakers.

[JonMarsh]

I get this feeling I'll be doing 2 versions, one with the ribbon and one with the Vifa, for all the designs. I'll probably shoot myself for saying this.

:rofl: :rofl: :rofl: :rofl: :rofl: :rofl: :rofl:


Jed, you're catching the same disease I have, too much imagination and curiosity, leading to excessive design and construction plans! Be careful Jed- in that direction lies the Dark side- you don't want to end up like Evil Twin, do you? :W

[JoshK]

I saw some requests/mentions of a MMTMM type speakers for higher sensitivity and benign impedance. Just thought I'd share this link I found in case anyone was interested. http://www.customanalogue.com/elsino...nore_index.htm

It looks like a well thought out, planned and executed design. It has different design goals than many of the designs here, but none-the-less laudable IMO. My interests have revolved around OB designs since hearing a couple, but I do like the fact that the speaker is designed so that tube amps (my audiophile cross) can be used.

I think taking this design as a starting point and working with it to use an MCM wg loaded seas tweeter and potentially the newer HDS peerless woofers would be a great project.

[opt-e]

Ok, as it appears from all the posts people seem to dig the idea of the following drivers.

TB W4, Fountek CD1.0 MT
TB W4, Fountek CD1.0 MTM to match above
TB W4 Full range minispeaker


TB W4, Vifa D26 Center horizontal MTM, I can try the Fountek CD1.0 in a center configuration, but if I get weird lobing cancelations I'll have to resort to a dome tweeter for a lower crossover point or try something innovative with driver layout. If you have ideas let me know.

Sounds good to me :T :T :T

[ific]

Another vote for NeoCD3 (MT/MTM), something like "MicroStatements"

ific.

[NateTTU]

If by chance the Neo CD3 was used in the MT how much would the price go up? Besides the inital cost of $35 extra per driver, would the crossover be more complex?

[cjd]

Ryan: snag one of those tweeters and we can swap it in before this big box goes home with you...

[Landroval]

If by chance the Neo CD3 was used in the MT how much would the price go up? Besides the inital cost of $35 extra per driver, would the crossover be more complex?

No if the crossover frequency is the same. Can be even cheaper if using lower order filter.

[Johnloudb]

Neo CD3

If by chance the Neo CD3 was used in the MT how much would the price go up? Besides the inital cost of $35 extra per driver, would the crossover be more complex?

Actually, I think the Neo CD3 could simplify the crossover. The overall sensitivity go up to 90dB also, instead of 89dB (That's for the MTM, the MT would be 87dB with either tweeter) I've got a 10watt amp.

[Jed]

Another vote for NeoCD3 (MT/MTM), something like "MicroStatements"

ific.

Stuck in St.Paul grrrr...

Jon I don't know how you do so much traveling!

Anyway if you guys don't mind paying a few extra bucks for the CD3, then that's the ribbon I would recommend for all the designs- even though the CD1 is a bit smaller diameter. As for crossovers, I don't think the parts count will be any different with either tweeter- probably either 3rd or 2nd order electrical to hit a 4th order slope. A lot of people think 2nd order acoustic slope is less parts, but that isn't always the case. When I get home I'll do some modeling of the baffle layouts and crossovers using the FRD tools. Then, when I get drivers in house, it'll be building and measuring full -time. What else could one ask for! :T Besides a cheap OB and MMTMMW of course.

[Jed]

:you don't want to end up like Evil Twin, do you? :W

I think everyone has a bit of Evil Twin in them ready to get unleashed. :W

[opt-e]

I'm down for the CD3.

[Jed]

I've been working on the cabinet designs a bit for the MTM, MT, and fullrange using W4 and CD3.0.

Not finalized or anything, but you get the idea for the basic concept with the space saving slot port. A front firing port is needed for those wishing to do a wall mount.

[Hdale85]

What are the size of those?

[Johnloudb]

I've been working on the cabinet designs a bit for the MTM, MT, and fullrange using W4 and CD3.0.

Not finalized or anything, but you get the idea for the basic concept with the space saving slot port. A front firing port is needed for those wishing to do a wall mount.

Looking very nice. You're doing a noble thing Jed.

[Jed]

What are the size of those?

each square = 1 square inch

I still have to play around with the volumes. I could probably make them a bit smaller.

[Jed]

Looking very nice. You're doing a noble thing Jed.

thanks- looking forward to making some dust this weekend. :T

[opt-e]

Looking very nice. You're doing a noble thing Jed.

Agreed. Your work does not go unappreciated! ;x(

[Hdale85]

So about 17"Hx6"Wx9.5"D for the MTM?

[Jed]

So about 17"Hx6"Wx9.5"D for the MTM?

Exactly, if that is not ok we could rear port it and make it a couple inches shorter, just that wouldn't work out for the guys who want to mount it on the wall.

[Hdale85]

Thats not too bad. Wouldn't be that hard to have 2 cabinet variations really. Honestly the cabinet can be to their design the crossover still works as long as the width of the front baffle is the same and the speakers are the same distance from the top edge.

[Jed]

And for aesthetics purposes and to get a feel for the WMTMW/MMTMM layout, here's a quick sketch. I was thinking dual RS150, dual 4" TB mid, and CD3.0. As someone mentioned, a 3-way with the RS150s would negate the need for sidefiring woofer and ease crossover design. I myself would rather see TMWWWW- but you be the judge [symmetry is nice and has its advantages]. Again, each square is 1".

[Hdale85]

50" tall hmm. Not to bad. 10" shorter then the Statements :B the other speaker I'm considering building. Although quite different design goals. A TMWWWW would be nice as I don't think I've seen one on these forums.