The Satori MTA- a two way, but with a checkered past and lots of different DNA

[JonMarsh]

And here we see some more of that slow but steady progress...

Another right side wall and top panel going together...






Next up will be inner and outer back panels- due to the spacing of the panels versus router cuts, , they will not be routed until assembled into the cabinet.

[JonMarsh]

And in the queue, one more left side wall to glue up, besides the back walls! (right after breakfast- all marked up and ready)

Then the modified below woofer wall spacers and tweeter side wall spacers will need to be glued to the back of the front panels!

Dr. Tihanji, who led the Siemens Balanstrasse facility I used to report to (back in the 80's) would definitely be nodding and repeating, "Slow work takes time..."

Me, why I just find the dramatic tension nearly unbearable! (Hah Hah!)
I just want to get to mounting drivers and making measurements and a crossover design!
Maybe even listening to these!

🤪

[JonMarsh]

103 F on tap today, and no, the garage is not air conditioned, so work early and work fast...do indoor stuff like updating the CAD files in afternoon and evening...

[JonMarsh]

Happy Saturday folks!

When I got up early this morning before sunrise, it was 10 degrees warmer than it has been most of the last month... not a good omen!

But work was engaged early... and not finished with all tasks for today yet!

Main step this morning was gluing up the inner back panels to the outer back panels, and making sure everything is aligned "just right"!



This involved measurements and some alignment marking, and double checking with a steel rule after the thin coat of epoxy is applied. Alignment lines drawn top and bottom after everything is lined up makes it easier to do when assembled with epoxy...





Note, I'm clamping at the ends, checking alignment, then adding maple ply scrap weight to compress in the center, using the table saw top as a stable flat plane.

I don't doubt the big boys can come up with a better plan, but I'm just the wires and sparks guy....






And I find that a key to having this all go "smoothly" is my Festool sander that I resurrected earlier this year!

[technodanvan]

Making really good progress Jon. You gonna finish this one?

[JonMarsh]

Now that's a worthwhile question, considering how many projects have been paused, but not deleted... Kurosawa cabinets and parts are all in storage still...

A couple of friends of mine agree that I may be neurodivergent in a sense also, but my problem may be Augmented Attention Hyperactive Achievement...

(that's how I like to think of it- )

Of course, AAHA! is a lot more funny than so many of the labels being tossed around (psychology is my area of formal education) to ponder than ADHD, for which there are a number of examples in my blood relations, some clinically diagnosed, others highly suspected due to behavioral issues (and ADHD was originally (before about the year 2000) only thought of as a male issue; for women its more AD; which is mainly a problem for them; for boys, HD manifests strongly, and that's a problem for every one around them). Those relative do find my high reading speed, behavior and closure rates very annoying... I have sympathy for them, but knowing what others have accomplished with this handicap, I also have expectations about what is possible with the right therapy. Therein lies the problem.

But these attempts at humor I bring up, like comparing elements of this project to a wedding, might be just simple attempts at deflections and efforts to be mildly entertaining- this is partly being driving by a couple of members who have a strong interest in doing what I'd call an M8ta "evolved"; with fairly top of the line drivers (OK, we're not talking PuriFi here, but this is hardly what I'd call a budget two way-).
And the enclosure concept is built on a past developed concept that I liked a lot, (Ardent D) using the same high grade woods and simplified finishing style.

Now, anyone else building this can use this enclosure build just as a suggestion or jumping off point- they could always fall back to the original M8ta builds and variation, using more conventional materials, like cabinet grade MDF, Bamboo ply, conventional ply; go for lower cost, and substitute different fabrication techniques, like the bevel cutting curve I made for my very first Ardent concept build (the one using dual Seas 7" woofers) with a Ryobi BT3100 table saw that had deeper blade cutting capability than normal due to a much smaller arbor diameter.

As always, DIYW can be very freeing, right? But then it involves more personal development and experimentation.

The thing holding back my pace is the epoxy setting time of the West System components I prefer to use, as well as the Bob Smith slow set epoxy for edge adhesive. Both really need 24 hours for a full cure. But, man, that's a really good joint they provide.

The high temperatures this summer have just complicated my daily schedule and ability to get diverse things done.

I do expect to be checking fitment for both enclosures tomorrow for the basic complete cabinet, and next glue the positioning pieces on the back of the front wall.

[JonMarsh]

Rise and shine! Rise and shine!

UPS delivered two days early on the PE order for binding post plates and binding posts... sometimes things go better than expected!



And the clamps are removed from the back panel assemblies, I think I'm ready to do an overall fitment check right after breakfast!



If that clears, then gluing the tweeter and woofer region positioning panels will be next!

[JonMarsh]

Preliminary fitment checks look OK...






Next up today is preparing the front panel alignment plates and marking up for precision alignment when gluing.


Step by step, inch by inch... slowly I build...

[JonMarsh]

Now, spacer panels added to back side of front panel baffles. New footer struts for inside bottom of cabinet fabricated, not yet mounted.

[JonMarsh]

Next Up- Side+top combo fitment check, epoxy tomorrow


This is probably more detail about building the cabinets than some are interested in, but several folks have commented that this is helpful, and it's also for the couple of guys that are seriously into this, so the details of how to do it THIS WAY are fairly clear, especially for others that may be helping out. These enclosures are intended to be very stiff and non-resonant. The edge board supports will give room for the Bessey clamp heads underneath.

Side View





Bottom's up!

[JonMarsh]

The base side to side internal cross braces are not yet installed, but have been basically fabricated. The drawings will be updated.

[JonMarsh]

I will be installing dual binding post assemblies to connect the mid woofer and tweeter to external crossovers. Note that the Woofer space plate can be covered with strips of 3" velcro, and crossovers mounted or removed fairly easily (relatively!) through the removable phenolic base.

[JonMarsh]

Making the "commitment" - after checking with both sides and back, glue up is started. To assure alignment each step of the way, I'm just adding one piece at a time- and of course cheating a bit on maintaining alignment with the Biscuit jointer. Though the Bob Smith epoxy sets up faster, that still means about 10-12 hours, instead of 20-24, so only one step per day.

And my scrap pieces of maple ply come in quite handy, as you can see below, but the same thing can be accomplished for assembly with just some cheap 2x4s.

[letiennam]

Nice detailing on the edges and panels!
Coming along very nicely- bonus points on work quality!

[JonMarsh]

Thank you thank you! Trying to set an example for other interested builders

[JonMarsh]

Today's work was interleaved with breakfast- not the way I usually do things, but I was hungry! And this was glued up and clamped by 9:30 AM!

A bit of clean up sanding and some biscuit joinery to aid alignment control:




Followed by a fitment check for the 2nd side...




Everything glued up and clamped- need to work reasonably quickly, as the BSI epoxy "slow set" is a max working time of 30 minutes






And a peak at the additional bottom side to side cross brace glued in:





Next today I'm shopping for some cable hold down clamps (nylon) and will be preparing cable pieces and the back plate connector, plus some damping materials; all will get installed while/before attaching the back (as of this morning's plan!)

[JonMarsh]

Tomorrow will probably be a repetition of this work for the other cabinet; I don't have space or working surfaces to work on both at the same time.

[JonMarsh]

Nice detailing on the edges and panels!
Coming along very nicely- bonus points on work quality!

Now, Letiennam, you know, in one sense I shouldn't be taking any credit for that- it's basically due to my choice of saw blades and router bits.

For example, the Bosch dual bevel sliding miter saw is equipped with a very nice ATB Forest Chopmaster blade.



By "very nice", I mean glass smooth surfaces to the cuts. Literally.

The manufacturer's description:

• Forrest's blades offer a superior cut that leaves a rip-cut saw edge that is as smooth as if it had been sanded, and a cross-cut edge that is almost mark-free. The blades run very quietly, and backside tearout in plywood is negligible. Each blade is virtually hand-made. The plate is hand-tensioned (up to 15 minutes per blade), superior C-4 carbide teeth are hand-brazed to the plate, and the blade is straightened and restraightened multiple times throughout the process. Think of a Forrest blade as a tool in your shop, not an accessory. Forrest stands behind it's blades by offering a sharpening service that bring blades back to the exact tolerances offered in a new blade. And this same exacting service is available for other manufacturer's blades as well, so they should come back better than new. Forrest Woodworker 1 Saw Blade For Radial and Table Saws. These trim and cross-cut ALL PURPOSE blades give scratch-free POLISHED cuts on wood, RIP or CROSSCUT, up to 2" thick. They have a 30° Alternate Top Bevel with a 5° Face Hook on 10" diameters and smaller.

Josh, the Nampa cop that lives across the street from us brought me some poles that they wanted to use for their shooting range at the Nampa police facility, but they needed to be cut down to size. I guess he's probably only used to seeing the results of cheap hand saws? As he admits, he's not a tool user himself, and not handy. (except with a pistol, I expect... )

So he was literally gobsmacked at the surface quality of the cuts I did quickly for him. This was last spring. Then he saw the Saint-Saëns LF cabinets in progress, and his next question was did I used to be a professional cabinet maker?

I said, nah, this is just my side with acoustics and speakers- I was a Distinguished Engineer for a German semiconductor manufacturer.

"So, you studied engineering in school?"

Nah, I'm just an ex gigging rock and roll musician with a psych degree.

Have to admit it, I love messing with some folks minds, and you know what they say, sometimes truth is stranger than fiction.

[JonMarsh]

OH, and this was a review of the CHOPMASTER blade on Amazon:

• We're rarely speechless around here, but after bringing this blade down through a gorgeous piece of maple, it nearly happened. We knew that Forrest makes some of the best blades on the planet, but we truly weren't prepared for the gorgeous cut we got with this blade. On the back side of plywood, we had zero tearout. When we cut a length of 8/4 oak, it felt like a hot knife through butter, and the result was too good to be believed: smooth as glass, completely free of circle marks of any kind, and it looked like it had been sanded already - cut after cut after cut. You can pick up a miter saw blade for a tenth of this price, of course. It will cut. But it won't cut like this. And it won't last as long as this blade will, not by a long shot. Because it's made of double-hard C-4 carbide, it holds it edge for what seems like forever, and it resharpens beautifully. Forrest spends a good deal of time on each blade, ensuring that it's as straight as can be, and that's part of what you're paying for. If you spent good money on a decent miter saw, you owe it to yourself to put this blade on it. After parting with your money, you will never regret buying this blade. --Kris Jensen-Van Hest

[JonMarsh]

Back to productivity, starting the cabinet glue up for #2...


After doing the biscuit joinery, piecing things together and checking that alignment is looking good with our wedding mandated "something blue" is a good idea...




So, mix up the Bob Smith Industries slow set or whatever YOUR favorite is (DIYW), apply to the front panel, then place and clamp the side + top panel assembly:




And if you're in the mood for it (I was), before snugging down the clamps tight, not a bad idea to re-check the angle fitment:

[JonMarsh]

Now, a possibly important thought to share, if you're more in favor of a traditional build with simpler materials and a veneer skin, thats certainly doable, using the original M8ta examples as a jumping off point, or even the Wavecor Ardent, with some simple adjustments.


Here's a reminder, my initial Wavecor Ardent build, front panel width is in the ball park, and here I used Birds Eye maple veneer to good effect:




This of course is more in the classic Avalon Acoustics style. As I mentioned before, one can even cut the bevels in the front panel if your table saw cuts deeper than average, and you can build a simple fixture to position it at 45 degrees, as shown in other posts.

And of course you don't need this much enclosure volume, so the front to back depth can be reduced to adjust that- look at how deep this goes in comparison to what I'm working on now.




This pair ended up going to a colleague and close friend, from East Germany; he still lives in the Bay Area with his daughter, but is looking into returning to Germany to work there for Infineon a while longer and then retire somewhere like Ilmenau.

[JonMarsh]

OK, ok, I'm late posting for what I worked on yesterday, but I've got a good excuse, and it's not that the dog ate my homework. It was Steve, and he didn't eat my homework, but he gave me an extra credit initial research assignment.

These lines from his first email about this explains the basics pretty well- nothing confidential or private here!

[QUOTE] It's been a minute since I built anything for myself, regardless of the contributing factors for that and I've been getting an itch. No fun just building stuff for others all the time.

I had been toying with the idea of repackaging my 1071's, http://www.troelsgravesen.dk/Jensen.htm. Instead of going with the ported base section, use a SS 26W PR.

Of course thoughts progressed and I started pondering a Calliope Supreme design. Use the Calliope mid and tweeter in a sealed upper section and a SS 26W/8861 and SS 26W PR in the lower./QUOTE]

Now, you know what a sucker I am for anything vaguely Calliope related- luv dat SB Acoustics MW19P series, and of course luv the Peerless DA25TX-08, the best $500 tweeter you can buy for around or under $75! This current project has a lot of DNA from the Calliope, too!

But, assuming that something based on the Calliope was a given for the midrange and highs, then that meant I needed to look into the Low end and see just what we have to work with. Any talk about PR's always perks my ears up...

So I started looking into the 26W/8861.. and the first thing that caught my eye was the Qes of 0.33... Bingo! Potential Bessel high pass configuration!

Now, Steve, being the practical and frugal sort, was hoping to get by with just a single PR, but the compliance doesn't work out right that way, and if the maths don't math, then ya gotta do what you gotta do. I'll skip through the intermediate details and show you what I came up with:




I suspected going into this that this Scanspeak part was something of a monkey coffin driver, and I wasn't wrong... 75L for a single 10" spills the beans. But what nice beans... solid loading down to a 20Hz Fb and a calculated -3 dB point of 35 Hz.

What's not to like? Other than these are not what you call "budget drivers"- but then, by contemporary standards, they're not budget busting, either.

We spent almost an hour talking on the phone about this and how to potentially approach crossover solutions, including a further review on my part of Troels efforts.

So, that's why my homework is late!

[JonMarsh]

Just steady progress here on the assembly work...

Of course, need to do a fitment check on the pieces before putting them together...




Biscuits in place as usual to help with maintaining the alignment during clamp up...




And here we have it glued up, proudly displaying my favorite Bob Smith Industries Epoxy in the foreground...




And another bit that needed attention to, gluing the intermediate cross braces on to the back panel, using ones made from some scrap 1-1/4" maple ply. Waste not, want not.


PR rebates and through holes won't get routed until after the backs are glued on. So that should be next up after a bit of sanding on the updated back panels.