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ajc9988
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So, some fit and finish decisions were made and the following have arrived:

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4 packs of these for a total of 16. I am using one pair per driver, then one pair for the plate I'm going to make per loudspeaker as a whole. So if I ever make a passive crossover, I just unplug the amp, then run the wire from the passive to plug into where each driver is. Also looks nice when you open up the back plate (from what I am envisioning).

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4-packs of these for a total of 20, but only 16 will be used. Solid aluminum potentiometer knurled knobs. This goes with the 4 potentiometer pots of the amplifier (which can be reprogrammed, trying to decide if I will and if so to what, but the knobs will be there).

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20 pairs of these plugs. Need 16 to match the speakers. Why these? Well, I bought some 10 AWG solid core to run in these speakers. And since I have a spool of 500ft, wondering if I might do something crazy like soldering two lengths together for each stretch of positive and negative, making it the equivalent of 7AWG, then just have one go a little longer to stick into these 90 deg. banana plugs. Not all play nice with 10AWG, so I went with something I knew would.

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Just a 4-pack of these 15A 125VAC plugs. Has a fuse compartment for the first line of defense for over-current protection.

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We all like a tactile feel when flipping something on. What is better for some tower speakers with an active crossover in the amp than having that hard click when you turn it on (while also having standby possible by shorting a circuit and that button will be on the back also, but this cuts the power between the plug and the power supply, rather than relying on the amp's circuits to go to standby, which is not off).

I'm still finalizing rubber feet and wood inserts for the speakers, feet, and plate amp, so that they can be taken off without worrying and you won't drill all the way into the compartment, leaving one less potential place for an air leak.

I will also have to get some quick connects from the posts to the drivers, but one more thing to the list.


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ajc9988
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I grabbed 4 of these 500W power supplies. I am designing the speakers for around 350W RMS tops. So, 80% of the power supply being 400W, these should do the job. These are 36V, 13A that were advertised for CCTV, Radio, and LED strips.

These will be paired with the JAB5 fro Wondom.

I'm mainly waiting on the subs ordered from a Finnish speaker company because Madisound was out of stock. The Finnish store was even cheaper than Madisound and have free international shipping. But, they only had two unspoken for in their late June shipment, so I do not know if I will get them shipped in June or July (I told them if they wanted, they could wait and ship all four together). But shipping and components, just like wood right now. Man...

But I do have the U18s and the 27TAC/Gb already. So the project is coming along slowly.

But feel free to drop some comments on the components, fit and finish, and anything really about the build.


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123Toid
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@ajc9988

I love the power supplies.  Which brand did you end up getting? Also where do you plan to get those potentiometer knobs from.  Thsoe look really nice.

https://www.youtube.com/123toid


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ajc9988
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@123toid -
https://www.amazon.com/dp/B08JHJXNPH?psc=1&ref=ppx_yo2_dt_b_product_details
Those are the knobs, and they also have a light blue (baby or powder blue), a red that comes off with shades of magenta, gold, and silver. Szliyands is the brand, 5-piece.

There are some cool options if looking through guitar knobs. Main thing is to make sure it matches what you are using, with 6mm being fairly standard.

As for the power supply, it was Yi Mei Da. Also they are now $50 each, which they were closer to $40 each when I bought them.

https://www.amazon.com/dp/B07W4J4K53?ref=ppx_yo2_dt_b_product_details&th=1

But it did take a lot of searching to find power supplies with 36V with the needed watts. The JAB5 recommends 36V, but the voltage range tops at 39V and minimum of 10V, so picking a 36V so as not to max the voltage seemed about right.

A lot of power supplies seem to have gone up in price since I bought them, unfortunately.


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ajc9988
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So, for those that are like me and think t-nuts are not as good as wood inserts, or just do not want to deal with t-nuts, here are the wood inserts I got for this project and why:

E-Z LOK - 901024-20 Threaded Insert, Zinc, Hex-Flanged, #10-24 Internal Threads, 0.787" Length (Pack of 50)

https://www.amazon.com/gp/product/B002WC8TTS/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

E-Z Lok Threaded Insert, Zinc, Hex-Flush, #8-32 Internal Threads, 10mm Length (Pack of 100)

https://www.amazon.com/gp/product/B002KT11XO/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

MroMax Wood Furniture M6 x 25mm Threaded Insert Nuts Interface Hex Socket Drive Carbon Steel Bronze Tone 50pcs

https://www.amazon.com/gp/product/B07X8LTKD9/ref=ppx_yo_dt_b_asin_image_o00_s01?ie=UTF8&psc=1

The first two are Zinc because they will be used to secure the drivers to the baffle. Specifically, the first one will work with the 5mm holes in most drivers, while the length will work easily with a double baffle (or if you are not doing it to keep the air seal and drilling straight through, just the benefit of NOT having to secure a T-nut that can fall off).

The second one is for smaller tweeters and such with 4.5mm holes, which have less weight, so the smaller length likely will not matter for securing the driver.

The last one is 1" m6 threaded inserts. You can get Zinc instead of carbon steel, but it costs more. I plan on using these to secure the feet (matches common spike sizes, even though I'm using rubber, makes it easy to switch in the future) and for the plate amp. That way to save the others for around the speakers.

I am likely also going to use waffle speaker grills. With a name like The Seas Speak, the waffle grills are to make people think of port holes and the grid metal grates on ships. Any effect on sound likely can be addressed with the DSP, and with wood inserts for the attachment of the waffle grills, there are no worries about removing them and putting them back on because nothing will wear out with the wood inserts.

But I mainly find 6.5" waffle grills and I need to check if that will work or not with the SEAS. I've been busy/lazy with research and haven't just gone and measured.

But that is a bit more about the aesthetics/fit and finish. And even though they are more expensive now (part on Trump and his trade war which Biden is continuing, part is shipping and lockdowns by Newsome in CA restricting offloading of products at the largest port in the US and other shipping costs), it really is the little things.

But the first one is harder to find, the 20mm version of the #10-24, so wanted to share.


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ajc9988
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Reminder for people purchasing female quick disconnect terminals for their speakers (which this will help generally for them coming off), ALWAYS use your calipers in order to verify the size of the male spade.

For example, I'm using 10 AWG Solid CU line. This makes finding appropriate connectors hard.

My speakers use 0.178" width terminals with a 0.020" depth. The power plugs I am using have 0.178" width and 0.032" depth. And finally the posts I am using through the wood use 0.205" width and 0.020" depth.

Now, the standard size for 10 AWG is a 0.25" connector. The gold plated ones from parts express do not give a depth. I have found 2 packages that will work for the 0.187" terminals, but am still searching for the 0.205" ones.

Most people do not consider the depth of the male terminal when buying connectors. This could be why people complain about them slipping off or not being snug enough on the terminal. So always pull those calipers out and make sure you get the right thing for your uses.


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ajc9988
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@123Toid - I don't know if this is a setting in windows (I run a custom rom and it does interfere with numerous software from various vendors), but the numbers I am getting off this sub is pretty far from the spec sheet and winISD is having the SPL way lower than what it should be when I enter the numbers in.

Now, I do think the speaker needs broken in could be part of the numbers. But is the winISD having the SPL more like 15-20dB lower than it should be normal?

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This is the scanspeak 30W/4558T00. Granted, this is sub number 1. I have 3 more to check. Just trying to make sure what I am seeing makes sense.

 

Edit: nevermind. I had the Vas set to liters in winISD, but was putting in cubic feet from DATS. My bad.


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ajc9988
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So, some information from DATS on the 4 subwoofers (30w/4558T00 Discovery line from scan-speak, which although listed in two ways for linear excursion, 12.5mm is the real one way excursion with the limit being 28mm, whereas elsewhere they listed the 2-way, which is 25mm and 56mm; https://www.scan-speak.dk/datasheet/pdf/30w-4558t00.pdf).

Here is running DATS on each speaker 11 times, with a reboot and retesting of the leads after the 5th run for each speaker:

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When the averages were plugged into winISD, this is the rough look, with recommending 4.65 cu ft and 4.965 cu ft (this one I ran a little while with the generator in DATS at 20 amplitude at the speaker's resonant frequency, so it being larger by more than a tenth of a foot compared to the next closest, 4.837, may explain why a larger disparity).

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This is with high pass set for 14.5hz and low pass set for 120Hz, with a port resonance above 380 Hz (more than two octaves above).

I am thinking of doing 5.5 cu. ft. with a 21.65 Hz tuning frequency. These don't hit as low as the spec sheet suggests, and the resonant frequency on all of them is above that of the spec sheet by 4-4.5Hz. That is fine for my purposes. They also have a sensitivity of about 2dB higher than the spec sheet. Also fine. The Qms was also significantly higher, while the Vas was closer to 133L instead of 197L. The diaphragm diameter was spot on, within 1 to 2mm for the most part, meaning any difference could have been my slight placement of my ruler or deformation with the ruler (I grabbed the blade from my combination square because it was handy, but is more hefty than a lighter steel ruler).

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The packing is awesome. the subs were in plastic bags, then placed in two piece foam formed to hold the subwoofer and support all critical parts, followed by a thin piece of cardboard wrapped one way, then a white strand the other to hold both pieces of the foam together.

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As you can see, that is a pretty solid looking product. With that said, with my altitude, I cannot run this more than 120W or it will exceed the cone excursion of 12.5mm. That is fine, because volume leveling these to the woofer and tweeter will only take around 90W due to the 2dB extra sensitivity. So, it looks like this speaker won't need to pull as much wattage to hit the SPL I'm targeting for the total FR.

Now I'll need to go back and check the specifics for the compartment size of the SEAS U18RNX-P and start figuring out the size. I'm planning on a slot vent at the bottom with two separators, so it is calculated as three separate vents. But this helps to keep the resonant frequency in check, considering I'm using two pieces of plywood together for each separator and for the shelf for the vent. Hence estimating port resonance to be 380Hz and above.


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TVOR-Ceasar
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Posted by: @ajc9988

...

Edit: nevermind. I had the Vas set to liters in winISD, but was putting in cubic feet from DATS. My bad.

I'm glad you posted this because I was having similar problems with a driver I was putting into WinISD. Sure enough, there it was in Liters, not Cu.Ft.

👍👍

-Charlie
https://www.youtube.com/user/TheTrueVoiceOfReason


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ajc9988
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@tvor-ceasar - It's something so simple and so easy to overlook. In fact, the meters and feet conversion wasn't done on a rover sent to Mars about a couple decades ago. Guess what happened to it. (hint: it came in too quickly and demolished itself; https://www.latimes.com/archives/la-xpm-1999-oct-01-mn-17288-story.html ).

But I'm glad that helped others here! Also, WinISD uses 1K on the L(e) value. At least my default under preferences in DATS was at 10K. So check that you have L(e) set to 1K there. Edit>preferences then in the menu, select show Le at 1 kHz. You might also want to set the SPL to 2.83Vrms/1m instead of 1W/m, but that is a personal choice.

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You can also set to use metric if you would like for units and/or volumes. Just so you can speed up your workflow in the future.

 

Edit: I found the 1kHz thing posted by a Chris Romer in this thread over at TechTalk sponsored by Parts Express: https://techtalk.parts-express.com/forum/tech-talk-forum/55177-ts-parameters-from-dats-insufficient-for-winisd-database?p=820260#post820260

Edit 2: I also forgot to mention I've tested all the drivers for rub and buzz using the highest test levels and the drivers have all passed.

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Although, it is easier to get the pass if you just keep going quickly rather than letting it settle after hearing the tone for the notification that pops up. So just move quickly and it will read well when clicking through. If letting it sit for awhile, it just seems to not track as well and I do not know why. But doing it that way gives a consistent result. And obviously, going to the normal guidelines also makes it pass easily. -40db is really quiet.


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123Toid
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@ajc9988 

Excellent writeups!  I am a sucker for the packaging.  SO I am glad to see it pacakaged so well.  THis si looking like it is going to be an awesome project!  I can't wait to see the rest.

https://www.youtube.com/123toid


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ajc9988
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@123toid - I'll be coming up with a parts list for the build soon enough, a mandatory tool list, a recommended tool list, etc. I'm really thinking of doing a write up how to build this exact project because, although expensive, it really is shaping up to be an excellent product. Due to the parts selected, there are 8 types of screws (possibly a ninth, unless I can make the one for the USB port also work to bolt in the power plug connector), 4 types of quick connects for 12-10 AWG (yellow), 1 ring connector, the rubber feet, three types of wood inserts (no T-nuts because I'm using a double baffle for the entire front and a triple baffle for the sub, with around 3/4in inserts for the speakers themselves, 1in inserts for the feet and to screw in the plate amp (6mm, so you can switch to screw in spikes if you care to at a later date), the sub and woofer have 5mm holes, the tweeter is 4.5mm, so had to use a different size there, but looking at a 4 bar and 3 bar speaker grill for the sub and woofer, which would have 5mm holes, meaning that there would be a total of around 88 of the inserts and screws for the grills and sub and woofer. I figure just use the 6mm on the plate amp as well since the only thing I needed them for was to strongly secure the feet. So that will go with the amp as well, meaning 40 of those are needed (I'm building 2 pair, so those numbers can be cut in half for a single pair).

Then I have two different standoffs for the PCBs from the aluminum plate (I bought 4 12x12x1/8in aluminum plates to cut down, then drill holes for the offsets, power switch, knobs, etc., along with cutting out the holes for the USB and power connector which has a fuse in it). I'll likely find a way to mount the bluetooth antenna (WIP). Then I have to write up about sanding to remove the aluminum oxide, applying the metal primer, then painting, how to make cardboard stencils, using that to paint the names identifying the different knobs, etc.

Then there is the use of finger joints for the sides, using the dado to create the top and bottom and some of the channels, making the vertical bracing open up so that it holds the vent shelf in place, adding more stabilization for the vent (which the bracing will be two vertical, two horizontal, with the vertical and horizontal slotting into each other, and since it is two plywood sheets thick, the horizontal ones will be done as a two piece, the piece that goes vertically up the back and runs the top and bottom of the compartment with the sub (with the bottom then splitting open with it continuing to the front of the speaker the height of the vent, then above the shelf for the vent coming toward the front) and then the top to bottom bracing in the middle. This way the wholly intact horizontal bracing slides into the vertical bracing at the back, then the cross brace in the middle also slides into the top to bottom bracing, thereby creating a tic tac toe type looking brace in the space of the compartment. It's easier to slide in, then glue those middle bracing with a section on one of the plywood parts of the brace cut out to create the joint for the middle bracing to the rest of the vertical bracing. This is with dados cut with either the table saw or the router for the bracing to firmly slide into and glue down, creating a strong mechanical connection to the outer frame of the compartment.

Or at least those are my thoughts so far. Once I have measurements finalized and sketched up, then I will be closer to finished. Also trying to finalize what insulation I will be using for each compartment and the sourcing (most likely Dacron in the sub compartment and lining the entire woofer/tweeter compartment with 2" rockwool 6 rigid board with dacron covering the wood from the braces, which should deal with reflections and standing waves).

Then pretty sure I will be using oil based finishes on the plywood, round-overs on the corners (which should look interesting with finger joints), an angle (undecided yet) for the transition from 3 baffles to 2 baffles, and throwing a couple pieces to back the area for the plate amp, which will need routed so the plate amp can be flush with the back, while also using the 1 inch inserts, although those are the only inserts I do not care if they go all the way into the inner cavity, whereas everywhere else on the build, no screws create any holes into the speaker compartments, meaning a good beading of silicon around the inside edges of each compartment should have a relatively sealed compartment for the speakers.

 


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