Kleos - Dipole Line Array

[Johnloudb]

Okay, just to let people (Hank) know I haven't been a slacker ... I've got two coats of poly on the second speaker, and will put a third on today.

[Hank]

Hurry up John - I want to know how the summitches sound! :yeah: I forgot - do you have any measurement equipment/software?

[Johnloudb]

Well, it kept threatening to rain and it sprinkled a bit, so I wasn't able to do any painting today. Next few days should be clear though.

Yeah, I want to know how they are going to sound to. Just have have to get past this miserable painting stuff. Won't be too much longer.

I plan on using my iPhone to take measurements, using Faberacoustical's Signal Scope app to start with. Will probably upgrade it to get all the full functionality of their software. I think that should be good enough, until I get fancy and add tweeters using a passive crossover. Then I may get some version of LspCAD.

[Hank]

We're on the edge of our seats, John. BTW, have you considered Active rather than Passive?

[Johnloudb]

I've been going back and forth on it for the tweeter/mid crossover. It will be an active crossover between the woofers and RD-50. We have three stereo amps to use but I'd rather use just two amps and cross over passively to the tweeter.

[Johnloudb]

Okay, I need some advice. The weather was bad for a bit and that slowed me down. I am going to sand and put one more coat on with the sprayer. Then what?

I saw some rub on poly also made by Minwax. Has anyone tried that? I was thinking maybe I could just put that on as a final coat. Like sand with 600 grit, after the final spray coat, and then put on a single coat of rub on poly?

Or should I just buff the finish, after the last coat I spray on? How do I do that? What do I need?

I know nothing about this and can't find any information. After I put on the last spray coat is will still have a somewhat rough texture and I can have that.

[Hank]

John, I haven't used rub-on poly, but wouldn't think it would be super smooth - maybe others here can give experience-based advice. You can go ahead and wet sand with 600 grit - VERY, VERY little pressure - wrap the paper around a wet sponge and use lots of water. If you have several coats already built up, you could then follow the 600 with 800 (IF you want).

[dar47]

I would not start that now it tends to pick up dust and needs a few coats so it doesn't look blotchy. If your happy with the thickness and texture of the finish I would leave the finish for at least a week to cure and harden, then bluff to get the specs and dust off then wax. This will give a furniture look when you look across the grain you see texture.

Wet sanding the last coat only looks good if it is rubbed out, eg 400 to level surface then 800, 1000 rubbing compound and then wax. This usually only looks good if the surface is filled with finish and some extra on top to bring down through the sanding process. If you wet sand now and polish you will see an uneven surface with an inconsistent polish. Wet sanding between coats is just to take dust off and level the surface. When I rub out I have a lot of coats so I can bring it flat.

[JonMarsh]

What he said...

I would not start that now it tends to pick up dust and needs a few coats so it doesn't look blotchy. If your happy with the thickness and texture of the finish I would leave the finish for at least a week to cure and harden, then bluff to get the specs and dust off then wax. This will give a furniture look when you look across the grain you see texture.

Wet sanding the last coat only looks good if it is rubbed out, eg 400 to level surface then 800, 1000 rubbing compound and then wax. This usually only looks good if the surface is filled with finish and some extra on top to bring down through the sanding process. If you wet sand now and polish you will see an uneven surface with an inconsistent polish. Wet sanding between coats is just to take dust off and level the surface. When I rub out I have a lot of coats so I can bring it flat.

:T

BTW, my finishing on the Arvo Pärt Picante's is Mini wax rub on poly- works fine, but as noted, you do need to give it a week to fully cure and harden. Also, I like using foam brushes to apply, not cloths. YMMV, of course.

IMO wipe on poly is one of the easiest, most fool proof ways to finish, requiring little skill or equipment, BUT, it just takes time, and usually 6-9 coats is where you want to be before a final wet sand and cover coat.

As I don't have a good place to spray something as large as the DeathStar project, THEY will probably be wipe on poly, too! (shudder- that's a lot of wiping...) :rofl:

[dar47]

A guy with all your skills Jon 8O , I think wipe on was invented for all the little ladies who never used a brush before. He jumped right over that skill and went for spraying which takes time to master but is faster. All hand tools are becoming a lost art but it works for me so I will stick with it. :B

[JonMarsh]

I've done spraying, too, and I like lacquer, but I have to "borrow" a place to do that, and at the moment that's not so easy, considering the space needed and conflicting need for ventilation and dust control. I learned my spraying chops on motorcycles in my misspent youth... probably Mike is the smart guy, now, with his Bentley specialist doing the lacquer!

I shouldn't have let "B" see my finished hardwood on the Arvo's; she would like me to do some work on some cabinets now...

[dar47]

I shouldn't have let "B" see my finished hardwood on the Arvo's; she would like me to do some work on some cabinets now...[/QUOTE]

Offer to pay for a "professional job" because that sounds like work that will take a lot time and doesn't sound like fun.

Are you doing the Death Star cabs yourself? I have access to free CNC so if you publish the Ardent Cabs maybe I could machine some parts for you? It may take some time as I'm learning but I have got some talented help.

Sorry John, I don't mean to interrupt your request for finish help.

[JonMarsh]

apologies for the interruption

I'll make this quick- sorry for the side tracking, John-

The cabinet rework under discussion WAS done by an outside "vendor" a while back; mostly OK, but some veneering and finishing not quite up to par. B does a lot of stuff herself, but this is beyond her skill set. not mine, though.


Right now, my set of Isis/DeathStar will still be traditional cut and assembly. I don't have access to a suitable CNC setup, and I'm not sure if my CAD software would directly support it- probably need to be post processed.

My cabinet design is simpler, and smaller, because I'm using all LBL bamboo (100%, that's not a typo) and this makes panels much stronger, which in some cases allows me to make them thinner, too, and to simplify the brace setup. NO 4" front panel here, move along folks. (Also, I'm going sealed not ported, which works fine with a smaller internal volume) .

At least, that's the theory. In my experience, unsupported six inch spans of 3/4" LBL are VERY stiff. We'll see soon how the practice works out. Hope to start cutting this weekend.

[Johnloudb]

Thanks for all the help! You guys rock!!! :T I bought some rub on poly and foam brushes. Still need to put on that last coat of spray poly, then I'll do the wet sand with 600 grit. Then I'll apply a couple coats of the rub on poly wet sanding in between coats. I will wait a week to let it harden before doing the last wet sand and final rub on poly coat.

No apologies necessary for the detour. Very nice looking model Jon!!! Will be fun to see the Isis/Deathstar come together.

John

[Johnloudb]

Rub-On Poly, You're my hero!!! ;x(

It worked really nice ... I put two coats on, and am waiting a week to let it harden as instructed, before I wet sand and put on a final coat. Speakers are now under the porch cause it's supposed to rain today and tomorrow ( lucky if more than a few drops fall though ). I'll get the other speaker caught up while I wait on the other one.

[JonMarsh]

Slow and steady gets it done!

[Johnloudb]

Slow and steady gets it done!

Will be testing that theory very soon, with the finish that is. Got distracted but each speaker just needs one final coat now. Honestly, designing a crossover for these has got be piece of cake, compared to the Horror of putting a finish on these suckers!!

[JonMarsh]

Will be testing that theory very soon, with the finish that is. Got distracted but each speaker just needs one final coat now. Honestly, designing a crossover for these has got be piece of cake, compared to the Horror of putting a finish on these suckers!!

Now, I can REALLY relate to that statement, as I'm much more a wires and sparks kind of guy than a woodworker- in the latter area, I always feel like a refugee from the amateur hour...

We each have our learning challenges...

Don't forget new pics when you're done!

[Johnloudb]

Okay, Hank!!! Got one done!

Got to let the poly harden a couple more days on the second one, before applying the final coat. Nothing but warm sunshine as far as the weatherman can see!!! :T

And I have simulated the HP an LP second order crossover in spice. That will be the building block for the crossover. Can get forth from two second order sections.

But won't actually start building anything till I can get some measurements and see was I need to do in the way of baffle step correction, etc.

[Johnloudb]

Now, I can REALLY relate to that statement, as I'm much more a wires and sparks kind of guy than a woodworker- in the latter area, I always feel like a refugee from the amateur hour...

Well, I wouldn't know it from looking at your work and build threads. :T

[Hank]

Atta boy, John! I may have asked, but have no memory - what measurement software/hardware do you have?

[Johnloudb]

Okay, here's a couple pics. Not the best picture unfortunately but they look nice and are smooth and good enough for me!



Opps, forgot to get the blue tape off the aluminum supports.

[Johnloudb]

Atta boy, John! I may have asked, but have no memory - what measurement software/hardware do you have?

Here ya go, from post 138 -

I plan on using my iPhone to take measurements, using Faberacoustical's Signal Scope app to start with. Will probably upgrade it to get all the full functionality of their software. I think that should be good enough, until I get fancy and add tweeters using a passive crossover. Then I may get some version of LspCAD.

[dar47]

Great job on the finish! Man from the Photo perspective they look to be a story tall.

[Johnloudb]

Thanks Dar! Yeah, that's kind of deceiving there. They are 5'6" tall.

[Hank]

They look great, John!

Opps, forgot to get the blue tape off the aluminum supports.

I dunno - the blue painter's tape adds a touch of "airyness" - if you will, a realistic spacing of instruments in the sound stage. I suggest you add more blue tape. I can get you a discount :W

[JonMarsh]

They look great, John!

I dunno - the blue painter's tape adds a touch of "airyness" - if you will, a realistic spacing of instruments in the sound stage. I suggest you add more blue tape. I can get you a discount :W

Hank is definitely the go-to guy for blue tape! Used to be for white tape, too, until they stopped making it. I'm still hoarding a few rolls…

[Johnloudb]

They look great, John!

I dunno - the blue painter's tape adds a touch of "airyness" - if you will, a realistic spacing of instruments in the sound stage. I suggest you add more blue tape. I can get you a discount :W

Thanks Hank! I don't doubt ya ... will give it serious consideration.

[gbegland]

Been following along since the beginning of this thread. The final product was worth the wait. Nice job with the baffles for sure....just don't make us wait that much longer for a working system. :W

Greg

[Johnloudb]

Thanks Greg! Yes, it has been a long road huh. This was essentially my first "real" word working project. Shouldn't take too long to finish it, I think.

[Johnloudb]

I finished the other one yesterday. Again I took pictures in the evening when the lighting is not good and casts lots of shadows, so I took a couple close up pics so the picture would turn out better.







So, I'm done with the baffle except for one little detail. I'm not happy with the way I've connected the baffle to the support. I used silicone sealant and clamped it tight, and it is solid, but I worry about it coming loose with the weight of the drivers, and vibrations.

So, I ordered some 3/16" X 3/4" steel dowel pins that I'll glue in with epoxy, where the supports connect to the aluminum. This means drilling some extra 3/16" holes on the inside (woofer side) of the supports.

[Hank]

Lookin' good. So, you attached the aluminum L brackets to the baffles with silicon sealant? Was your intent to have a damped attachment? I'm on the fence here - the length of the attachment may be okay re the moderate adhesiveness of the sealant, but part of me would want to attach the brackets to the baffle with screws. How about this: separate the brackets from the baffles, clean up the sealant, then screw the brackets to the baffles with neoprene washers under the screw heads and also between brackets and baffles? Mechanically strong, but decoupled.

[Johnloudb]

Oh, the baffles are attached to the aluminum angle with many screws and silicone sealant. It's the connection to the supports that I'm concerned about. There are scews that clamp the supports to the aluminum but are not physically attached to the aluminum. See, I've been moving the speakers around a lot on a hand truck and I'd pull on the top of the baffle when tilting the speaker back on the truck. A while back I heard a creak and saw the baffle move a bit on one speaker. I found the all the screws were loose ... I forgot to tighten them down after I attached the supports to it, long ago. ops: I used silicone cause it's a pretty good glue and will attach to most materials. Anyway, I tightened the screws down good and it won't budge now, but I need a more solid connection. The dowel pins, along with the clamping screws there already, will prevent any movement and make a real strong connection, I think.

[JonMarsh]

Devil's in the details, isn't it John?

They ARE looking good, though! :T

[Johnloudb]

Thanks Jon, yep the details will bite you in rear every time! :demon: :M

[Hank]

Jon espouses another pearl of wisdom. Details, over many speaker cab builds have always made me:
mad
disappointed
ashamed
upset
embarrassed
swear off speaker building
reach for the tequila

[JonMarsh]

Now Hank, you know, of all of those things you listed, all should be given short shrift and shrugged off as part of the learning curve, except the last one, which is always an appropriate start to any meditating session on lessons learned!

Especially the next to last one is strictly off limits!

[Johnloudb]

My dowel pins came Wednesday, and today I epoxied four of them in my speaker. I placed them so the fender washers would cover them up. Ha ...



Covered with fender washer -



So, I'll be finishing this next couple days.

[Hank]

Good. And sublime that you retain the 3M blue painter's tape for that last degree of soundstage reality - brings a tear to my eye.

[Johnloudb]

Well, I finished my speaker cabinets today. :banana: Will bring them indoors and hope to set up soon. Got to displace my dad's speakers. Unfortunately my dad is on vacation in two days and will likely not let do anything during that time.

[Johnloudb]

Good. And sublime that you retain the 3M blue painter's tape for that last degree of soundstage reality - brings a tear to my eye.

You hang to that Hank! :T

[Hank]

Hark! Do I hear a cordless screwdriver installing multiple drivers on a LA baffle this weekend?

[JonMarsh]

My dowel pins came Wednesday, and today I epoxied four of them in my speaker. I placed them so the fender washers would cover them up. Ha ...



Covered with fender washer -



So, I'll be finishing this next couple days.

Slick! Good progress... keep the pictures coming!

How about loading some drivers now? :W

[Johnloudb]

Well, I'm bringing the speakers in today, which are currently outside, protected under our porch. Drivers? Hmm .... I've some work to do on our room first and if I get daring I'll post some pictures ...

Every speaker needs a crossover ...



Response ... it's forth order, not second order like it says. This is kind of an LR4 but It's not butterworth filters, it's two cascaded Bessel filters, for no reason other than I was too lazy to recalculate the C values for the forth order. Any, I'll have plenty of time to play with it, once i get some speaker measurements.ac

[Johnloudb]

I got the speakers in the house yesterday. I need to order speaker gasket stuff, screws, and grill cloth for the RD50. And wire too!