Rosso-6MW150D sealed enclosure size

Any bed or mattress store will sell urethane foam padding which works excellent as dampening material applied to the enclosure walls. Dont use fiberglass or rockwool dampening unless covering the back of the driver with grille cloth or nylon panty hose - the fibers can end in the exposed VC gap, contaminating it.
There are different strengths soft med and hard is this the damping material to get and how thick of a material should I get

Is this the right material cheers Rick
No, foam is not what you need. You need an open damping material, fibers like Rockwool of polyester pillow filling.
You need to prevent the damping material from touching the cone from the back and /or small fibers or dust entering the voice coil.

It may sound a bit rude, but the damping material is about 0.01% of your problems. Building a 3-way speaker without any experience and basic knowledge of acoustics, measuring and electronics is simply impossible, even if you have very low expectations.
To tell you the truth: Even if you find the world best tweeter, mid and woofer, you can not even build a medium quality speaker.
Get some measuring gear and build a nice, well reputated DIYS 2-way. Use it to learn about speaker building, measuring and crossover development (doesn't matter active or passive), do some experimenting and read a lot.
OK, such is no project with guaranteed bragging rights, but you could learn and some day build a decend 3-way tower.

Speaker developer is a very rare and, if you are good at it and reliable, well paid profession. Most of these guys spent years at some university. Maybe think about it.
I know you won't like this post, but if you take it serious, it will save you time, money and frustration. If you urgendly need a 3-way, there sure is a nice kit if you look worldwide.
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@Turbowatch2 @Rick2023 The proper type of foam for enclosure dampening is low to medium density open cell urethane foam. Only open cell foam will work. Closed cell foam acts like a solid in a speaker enclosure, raising Fb due to reduced volume. Some slightly better, wider band absorption mediums are sheeps wool, rockwool, fiberglass wool and melamine foam.
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This is the Rosso in different enclosure sizes (TSPs from SB audience, 0,5 Ohms series resistance from xover, 20% stufffing):

View attachment 1283759

You see, the behaviour >500Hz is neary not affected by the volume. Also, once above 8 liters the behaviour < 500Hz is varying not much when the volume is increased. So for midrange application, the enclosure volume is rather uncritical, you have a wide range to choose from. Personally, I would give it >= 10 liters to have enough stuffed volume to absorb the rear sound of the mid poperly, but I would let me also drive by a meanigful construction design of the cabinet.
Are you using Vituix cad for this graph
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@profiguy what kind of spacing do you think I should do for the drivers on the baffle I’ll show a photo on how I want to place the drivers but idk about spacing.

I received the xt25bg60-04 and wg148r
I removed the faceplates they were also screwed and glued down i never pullled one apart and I couldn’t find a video.

I did accidentally gently pull from the wrong section but pushed it back down got a flat head screwdriver wrapped the screwdriver in electrical tape to stop it Scratching up the surface and I had to put some twisting force between the actual face plate and tweeter right between the glue join it separates in two I installed the 3D printed adaptor should of used petg but only had pla+ at the time slapped on the wave guide and it looks good there is a bit of a difference I played a couple of tones 3.5khz 12khz and 16khz on the signal gen only on 1v peak to peak.

I might end up gluing the 3D printed adapter on to the tweeter body because it’s not really a good idea just using 3 screws I could literally move it if a gently press on it and I’ll throw some glue tack or butyl rubber around the adaptor to the wave guide there’s 2 slight openings between the wave guide and the adaptor plate I could glue it but if I ever want to change tweeter for what ever reason I can reuse the wave guides because there massive hole in the baffle and don’t want to fill it in with wood rather reuse wave guide.

So far so good.

Anyone know where I can find butyl rubber in Australia in like a string shape like second skin does in USA.


Btw i thought the tweeters where damaged because DigiKey thought it was a grate idea to not shipp the drivers in the original box but just wrap them separately Bubble wrap them and then place both drivers together in a bag then in a box with 2 layers of paper mesh stuff the magnet of one was touching the phase plug so lucky that it didn’t crush the diaphragms I sent digikey a email they apologised for the warehouse doing the wrong thing.

Idk why they did what they did but lucky they are not damaged.

Sorry for long post.
I forgot the photo
@profiguy I had to go with another company for foam because last company wanted me to spend a min of $400 AUD or $263 USD just on foam
¯\(ツ)/¯ idk why have a min spend of $400 seems weird.

So I found a new company which has similar specs of the foam plus I think I found the adhesive spray you was talking about and it’s local ish
@profiguy I think I messed up bad on driver location on the baffle the midrange driver is so close to the foam and the cut out is about 15mm away from mdf / the bottom of the sealed enclosure I wanted to place all the drivers as close as possible but idk if I’m going to run in to any issues of the midrange sound idk what do you think do you think it will be ok.

btw that 3M spray adhesive is good stuff I and should of used gloves lol

I think you'll be ok with the tweeter being that close, but make sure you countersink the mid flush with the baffle. If you're concerned about tweeter diffraction from the surround, you can use some thin, medium density wool felt or open cell foam in the height of rhe surround, placed around the tweeter dome perimeter to "soak up" some of the higher frequency radiated energy and create an acoustically flat surface. The idea is to soak up some of the HF energy so it doesn't reach and diffract at the mid surround. JBL did this with their LE26 cone tweeter.


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I won’t be able to flush mount the midrange do you think foam on the waveguide would be ok the middle hole is for the midrange the top hole is for tweet and the bottom hole is for the 10” woofer I was worried about the midrange being so close to the bottom of the sealed enclosure from the bottom of the cut out the foam is almost flush with the midrange cutout so 25mm of foam then the wood is there I wasn’t sure if I would have any problems cheers Rick
@profiguy I wired up the speakers and had a listen to one of them since I’m still making the other one it sound ok I noticed there’s a lot of midrange I could say it’s harsh I had to dip out the midrange a bit but still finding that it’s still abit much even if I spin the enclosure around 180 facing towards the wall @about 3-4ft away it’s better but I think it’s midrange here’s a photo of the eq do you think it would be a crossover issue or just a driver issue or eq

Cheers Rick
Without measuring and just looking at your EQ curve, it appears you need a good amount of BSC and dampening of the rising FR which is normal. It would help slot to take some basic measurements on and off axis. That mid is capable of smooth response, especially on a larger baffle. Also, not knowing exactly where the acoustic center is in relation to the horn driver makes things much more convoluted in terms of achieving good phase alignment and smooth FR on / off axis.
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BSC = Baffle Step Compensation. Its counteracting the baffle's influence on FR based on its width, causing a gradual rise in driver outout as the frequency increases. Most drivers are measured using a very large IEC spec baffle to minimize its influence on the driver's anechoic FR. This is why you need to consider the baffle size (specifically width) to predict driver FR when mounted in an enclosure. Both the baffle width and enclosure volume have significant effect on final driver FR.

I'd purchase a DATS V3 system if you want an easy to use, basic measurement system. The alternative is your choice in calibrated measurement mic used with a decent 2 ch USB interface with a program called REW. This option allows for relative phase measurements, which DATS V3 can't do. You need a mic with a known CAL file to get accurate results.
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If I tried flush mounting the drivers I know I’ll definitely mess up the enclosure would a 2nd piece of wood same thickness as the basket thickness help I’d have to do the tweeter and the midrange drivers I think the width of the baffle is 408mm wide hole speaker baffle is 777mm or 813mm long inc top and bottom pieces I think the basket thickness is like 3-4mm wave guide is thicker by a little bit more