SDA Custom Circuit Boards ?

gimpod

I don't know how many of you guys have seen my rebuilt 1C crossovers Link Post's #13.#14
Some of you guys have expressed some interest in maybe getting the boards and that's what this thread is about gauging interest.

I talked to Polk yesterday and they told me that as long as I did not use the Polk logo and make sure that everybody understands that Polk Audio has absolutely nothing to do with or has any responsibility for these boards that they would not have any problems with me making the boards available to CP members.

Now what I was thinking of doing was redesigning the original single board crossover so that it would accommodate the larger cap's like the Sonicap's and the like. That way you could use the new boards on any of the SDAs that use the single board design. Now as far as I can tell I think these are the SDAs that use the single board crossover. 1C, 2B, CRS+, SRS 2(1987) and SRS 3.1TL basically any of the SDAs that used the pin/blade IC. If you guys could help me out with this by supplying as high res pics as you can of the original crossovers (Top & Bottom) for the different SDA's that would be a big help. You can ether post them here or e-mail to "gimpod at comcast dot net" with the subject "SDA Crossovers" I would appreciate it.

P.S. Forgot to mention these would be bare boards also not sure what it would cost, I paid just under $90 for mine a bulk order would be a lot cheaper.

nooshinjohn

I am down for a set for the 2.3TL's...

F1nut

What the heck, put me down for a set for the 2.3TL's.

FTGV

I'm not sure of the price break points but ordering from a production house in quantities of >50 or 100 should bring the individual price down substantially.

george daniel

me too--set of 1C's

ESavinon

I'm interested.

heiney9

I'm interested pending costs.

H9

Conradicles

I may be interested pending price for a set of SDA-2B's with the TL Modification...

michaeljhsda2

I have 2 pair of SDA 1C's....I'll take 2 pair please.

headrott

Yes, 3.1TL's and 2BTL's as Brock said pending costs.

Greg

Outfitter03

I would be interested in a pair for SDA-1C.

Sig

Bobsama

I'm curious about a set for original SDA-1's.

helipilotdoug

Your boards look great! So neat and large enough for the new caps. Is there any way you could make a single board for speakers like my SRS 2 1986 version that have 2 boards? I know it would take a complete re design to do this, so just wondered if it might be possible. Thanks

audiobilly

I am in for a set for the 1Cs'!

fbm211

Im in for a set for 2Bs

Hawkeye

I'd be interested in a set for my SRS 2 P/B if I was able to use my Dueland Resistors which are 5.25 inches long. Doable?

Gordon

DarqueKnight

Those custom boards look fantastic, especially with the upgrade parts installed. Forum member Madmax discussed having some custom boards made for his SDA SRS's, but I don't know if he ever did.

I would like a set of these for my SDA 1.2TL's when you get set up to take orders.

gimpod

Hold on a second guys, I'm no where near ready to start taking orders there's still a lot of work that has to be done before I get to that point this is by no means a simple weekend job this is going to take a lot of work if I'm going to do it right. As a mater of fact I spent all day yesterday getting the original design into my cad program and I'm still not done. But for those of you that have requested a pair you'll get first crack at them.

Cost, Now this all depends on the final size of the board and the numbered ordered. But I can say it should not be more than $90 for the pair delivered anywhere in the lower 48.

I've made a decision I'm only going to do the single board style crossover for now using Sonicap & Mills components, Not to say you couldn't use other components but making them fit would be up to you. The other one's I could do but I would need the crossovers & the new components in hand for the first of a particular model in order to do it and they would be very expensive involving 2 separate orders and a boat load of time as they would be treated as a one-off special order.

So it comes down to these models that the boards would/should work in. (Hint, Hint, I need pictures guys!)
SDA 1C, SDA 2B, SDA CRS+. SDA SRS 2 (pb only), SDA SRS 2.3 & TL, SDA SRS 3.1TL and maybe the SDA SRS 1.2 & TL (Don't know if the 1.2's use the single board or not. "Hint, Hint, I need pictures guys!")

As far as making the boards compatible for the SDA 2BTL mod I don't know I would need really good pics of the original 2B crossover as a matter of fact I need really good pics (Top view and an Angled Top view) of all of the original crossovers except 1C's and SDA SRS 2's. The area I'm really interested in seeing is the HF or Tweeter section, Maybe you guys could take some closeups of both the HF and LF sections that would be a big help. Once again you can e-mail the pics to me at "gimpod at comcast dot net" with the subject of "SDA Crossovers"

WastelandWand'r

As a matter of interest and to assist you in your litmus test, I would be interested in a set with particular interest for 1C's. If you complete any other boards in the future and I have the corresponding speaker I would be interested in additional set(s).
Hope this helps, and good luck on the efforts. The ones shown in the other thread look great.
Nathan

JayCee

I'm interested for a pair of 1Cs and 1.2TLs.

gim54pod wrote: »

..maybe the SDA SRS 1.2 & TL (Don't know if the 1.2's use the single board or not. "Hint, Hint, I need pictures guys!")

I've attached pics from one of my 1.2 TL XOs. I don't have naked shots of the board, but do have more pics from other angles and of specific parts. Let me know if you'd like them, too.

John

gimpod

Hi guy's got my 1C's back together Sunday and finely working Wednesday (Note to one's self: Don't assemble speakers and watch the Seahawks at the same time) had a few drivers miswired:o. Been running them about 10 hrs a day and today is Pink Floyd day maybe tomorrow too:).

Now as far as making these PCB's available to you guys I'm still working on the design, But that's going to have to be put on hold till after the new year. I'm moving the middle of November and yes it will take me a month and a half to get all packed up and ready to move, I've got 20 year's of crap to go through some of which probably hasn't seen the light of day for that long. The only reason I'm moving is because the new apartment is fully ADA compliant with a ROLL-IN shower. Now finding an fully ADA compliant apartment with a roll-in shower around here would be like buying a house and after moving in discovering a locked closet that has a pair of factory sealed never been touched SDA SRS 1.2TL's personally signed by Mathew Polk!

BTW I still need pic's of the top and bottom of the originals mainly the 2.3's and 2B's or CRS+.

JayCee wrote: »

I'm interested for a pair of 1Cs and 1.2TLs.

I've attached pics from one of my 1.2 TL XOs. I don't have naked shots of the board, but do have more pics from other angles and of specific parts. Let me know if you'd like them, too.

John

Thank's John, more pic's the better also if you could get me some pic's of the bottom along with the height and width of the hole the crossover plate covers that would be great.

Thank's guys ~ gimpod

Outfitter03

Congratulations on finding a new place to live with better standards for independent living. Shame that they are so rare. Maybe some of that will change for the next generation as the Boomers age and see the light.

Are you seeing a lot of change as your caps burn in? Should have what? 30-40 hours on them by today.

vmaxer

Depending on the cost, I am interested - I have a pair of 1C's and 1.2TL's

Bubinga99

Very generous of you gimpod. There's a lot of tedious work involved with doing all these layouts to accommodate all conceivable R-L-C combinations and sizes, not to mention picking new connectors for all the speaker configurations that are readily available for low cost in small quantities and don't require expensive special crimp tools.

Adding some perimeter mounting holes to the board, so it can be mounted away/detatched from the big inductor, on standoffs, might be worth considering too.

Another thought to reduce cost would be to not have any holes, and people drill their own holes based on the component sizes they choose. Since this is just 1-sided copper there's no danger of shorting out internal layers or front-to-back shorts from smeared copper. Could also lap solder the components, but you'd want to have copper on the front side rather than the back.

Lasareath, re:

Lasareath wrote: »

I would love to have a set that had some kind of quick connector that allows us to swap out caps and resisitors very quickly so that we can try out different values and manufacturers?

So basicially no solder holes, just some sort of clip to grab onto the legs of a cap or resistor.

Universal breadboards are available in various sizes (see for example: http://www.ted-kyte.com/3D/Pictures/Breadboard.jpg ). These have a spring/clasp in the holes so they grab just about any wire diameter.

Trouble is, you'd lose the benefit of the quick connect since you'd spend far more time installing/removing the passive radiator to get to it each time you made a change. You'd be better off with some type of temporary externally-mounted crossover board. Also, you could lap-solder the components, which makes it much faster to change out a component compared to thru-hole.

Bubinga99

Lasareath wrote: »

From Looking at the pics above I'm pretty sure everyone has the same P1 & P2 connector. But that P3 is most likely going to be different. As you can see the end connection points use a different shape so that you don't plug the mid-bass drivers in the wrong direction.

That will help if that's the case. BTW, the original connectors in SDA were discontinued long ago (I checked into this several months back, and also called Polk), so you'd need a new male-female pair (probably a good idea even if the originals were reusable). While you might think all 1x4 connectors are the same, not true. Even a 1x4 from the same maker will have (intentional) variations, denoted by different "dash numbers" when you order. There are different pin size and spacing for the board mount side and the mating side, different shround shapes and sizes and keying, and the same for the mating connector. There are plenty of suitable substitutes, but you'll need to agree on one specific mated pair (brand. model, and dash number) for each connector size. Preferably one that doesn't require an expensive special crimp tool.

mrbigbluelight

Bubinga99 wrote: »

Very generous of you gimpod. There's a lot of tedious work involved with doing all these layouts to accommodate all conceivable R-L-C combinations and sizes, not to mention picking new connectors for all the speaker configurations that are readily available for low cost in small quantities and don't require expensive special crimp tools.

Adding some perimeter mounting holes to the board, so it can be mounted away/detatched from the big inductor, on standoffs, might be worth considering too.

Another thought to reduce cost would be to not have any holes, and people drill their own holes based on the component sizes they choose. Since this is just 1-sided copper there's no danger of shorting out internal layers or front-to-back shorts from smeared copper. Could also lap solder the components, but you'd want to have copper on the front side rather than the back.

Excellent suggestions, Bubinga99.
Others may have different experiences, but the only problem I've ever had etching/drilling/soldering PCB's has been with drilling holes (and this is with 1-sided boards).
Sounds like the easiest thing to do, but ..... ...... never lifted a pad/trace soldering, but drilling ? I know there's only one moving part (the bit), but .... :o.


Good idea, gim54pod.

gimpod

Thanks guy for your suggestions & comments there appreciated.

How are they sounding, The first day I was really disappointed and thought I'd screwed something up in the crossovers, they sounded flat and had a very narrow sound stage with no depth by the end of day two it was like day and night the flatness was gone and the sound stage had widened up quite a bit along with the depth. There sound pretty good right now. I know they'll keep changing as they burn in going from good to bad and back again. Can't wait for that 300+ hr mark. One thing I know for sure is these suckers are lease breakers :cool:.

Let's get the connector question answered (P1, P2, P3). They are "AMP Universal MATE-N-LOCK Connectors (vertical pin headers) with 0.250 in centers" and can be had at mouser (catalog page 1409), They are an exact replacement and mate perfectly with the female connectors on the wiring looms with one exception they don't have that tiny little nylon polarizing pin on the bottom so you just have to be sure of the orientation before they get soldered in. The little nub's on the side go up for P1 and P2 and down for P3.

Broken down by connector:
P1 is ether a 3 or 5 pin header depending on how many binding post you have 2 or 4.
P2 is a 4 pin header for all the SDA's were talking about.
P3 is ether a 2, 4, 6, or 8 pin header again depending on how many tweeters you have 1, 2, 3 or 4.

Lasareath wrote: »

I would love to have a set that had some kind of quick connector that allows us to swap out caps and resisitors very quickly so that we can try out different values and manufacturers?

So basicially no solder holes, just some sort of clip to grab onto the legs of a cap or resistor.

It's possible for that matter you could just get a bag of little alligator clips and solder them in with short leads, how you would hold the components down I don't know maybe double sided sticky foam tape ether way I don't think you would like the results. It sounds like a good idea but I'll bet you that if you built up 2 identical sets of boards one with quick connects and one without that they would end up sounding different.

Bubinga99:
The "Perimeter mounting holes" is an excellent idea that would give people more flexibility in mounting and would be real easy to do. Now making them without holes (I'm assuming for the cap's and resistors) I think would end up being more expensive and trouble for everyone in the long run. Lets face it drilling PCB's by hand is a big PITA, those little drill bit's get expensive when you consider how easy they break even using a drill press and how quickly the get dull, That copper is not as easy to drill as one would think. I could see some one going through 10 - 20 of them (at a couple bucks each) doing one set of boards.

Once again thanks for the ideas and suggestions it help's, keep them coming. I'm going back to my all Pink Floyd Sunday and working on these boards.

~ gimpod

amulford

I'll take a set for Crs+'s and 2B's, if I could

gimpod

Ok guys I've got the design of the PCB's done and they have extra mounting holes at the four corners. The boards measure 10 inches wide and 5 1/4 inches high and should work for any SDA's that use the single board design (2B, CRS+, 1C, SRS 2 (1987), 3.1TL, 2.3, 2.3TL, 1.2, 1.2TL). Let me know what you think.

~ gimpod

michaeljhsda2

Nice! Looks like a lot more room for the Clarity ESA and PX caps I'm gonna install in both pair of my 1C's.

F1nut

Yeah man!