TL Mod & The SDA-2B's, GREEN LIGHT!

jcandy

To be clear, you'll note that the faceplate on the RDO-194 is up-down symmetric (see right image), so you have to look at the actual terminal on the tweeter to see if the top is positive or negative. Because the SL-2000T faceplate (see left image) is not up-down symmetric, the orientation is perhaps less confusing.

audiocr381ve

jcandy wrote: »

To be clear, you'll note that the faceplate on the RDO-194 is up-down symmetric (see right image), so you have to look at the actual terminal on the tweeter to see if the top is positive or negative. Because the SL-2000T faceplate (see left image) is not up-down symmetric, the orientation is perhaps less confusing.

Jeff, thanks for clearing that up. Super helpful stuff.

audiocr381ve

Hi guys,

The following comes in tomorrow:

24 ft. Cardas Quad-Eutectic solder
2 Mills MRA-12 0.5 ohm
2 Mills MRA-12 2.7 ohms
2 Sonicap 5.8uF 200VDC (custom) - matched
2 Sonicap 12uF 200VDC - matched

I want to get a head start on asking questions before I start touching anything. (BTW my wife just walked by and read this and said "You're such a geek").

Please forgive my elementary questions, I don't consider myself to be the sharpest tool in the shed and I am an extremely visual learner. I could learn more from a picture than 100 hours of lectures.

Attached are two images. Please entertain me here. One was left blank on purpose for your input. The other is for your review and correction.

Update: JUST FOUND THIS INFO, but please comment anyway.

To do the "TL" upgrade do as above adding a 5.8uF Sonicap (custom value) in the C5 position, running the one lead into the H hole and the other lead into the C5 hole closest to R2.

EDIT: One thing to note is that on my crossovers, the H hole was covered up by the hot glue from the small corner inductor. Carefully pry the glue off to expose the H hole.

As he mentions the 5.8uF is a custom value, it's not part of their stock parts list but they will make it for you (by the way, "they" is Sonic Craft, at http://www.soniccraft.com. Fantastic customer service.)

The little brown cap in the picture of the parts I pulled is the bypass cap. The advice on other threads is that when using high quality caps like the Sonicaps, the bypass cap is no longer needed. I did not use one, and am certainly not hearing anything to make me regret that decision.

The beige rectangular piece is the 2.7ohm resistor. I replaced this with a 12w Mills.

The tiny blue piece is the polyswitch, which disables the tweeters if your amp starts clipping. This is noted to degrade sound quality. So if you're using a high quality amp and don't push the volume to the point of clipping, pull this piece and replace it with a jumper (I used 18g solid copper here as well). If you've tripped the polyswitch in the past, probably better to replace it. Get a new one from Polk, I believe they're free....

audiocr381ve

After catching some stuff in threads I've read over several times, here is a revised "blueprint" so to speak. Please advise.


Uhh, I may be getting a little to excited, or, it is too late to be thinking about this stuff. I just read more posts and am finding all the information I need.

I do have another question, when installing the caps, some mention their being a positive end and a negative end. Does this matter with these kinds of caps? I also need some sort of drawing to help me when paralleling the two 20uF caps (for the 40uF position).

Going to bed now...

jcandy

audiocr381ve wrote: »

I do have another question, when installing the caps, some mention their being a positive end and a negative end. Does this matter with these kinds of caps?

Audio-grade polypropylene capacitors are non-polarized, meaning there is no positive or negative terminal.

audiocr381ve

jcandy wrote: »

Audio-grade polypropylene capacitors are non-polarized, meaning there is no positive or negative terminal.

Thanks Jeff. You are going to have to come over and take a listen when it's all finished

jcandy

audiocr381ve wrote: »

Thanks Jeff. You are going to have to come over and take a listen when it's all finished

I'm there, dude

audiocr381ve

jcandy wrote: »

I'm there, dude

Haha, cool.

audiocr381ve

jcandy wrote: »

Audio-grade polypropylene capacitors are non-polarized, meaning there is no positive or negative terminal.

What about the resistors?

jcandy

audiocr381ve wrote: »

What about the resistors?

All your passive components (resistors, inductors and capacitors) are non-polar.

audiocr381ve

Would somebody review this?

5.8 cap far left
2.7 resistor next to it
.5 resistor replaced the polyswitch
bypass cap removed

audiocr381ve

After doing a bit more research, it seems people are doing different things with the 2.7 Resistor.

Here are pictures to compare with my post above.

I followed the first picture. I want to know why people chose to do it different ways. Which way is correct for my pin/blade SDA-2B version?

Confused in San Diego,
Shane

On3s&Z3r0s

I like the third pic with the 2.7 Mills piggybacked on the 5.8uF cap. It definitely gets the clean and tidy vote.

audiocr381ve

On3s&Z3r0s wrote: »

I like the third pic with the 2.7 Mills piggybacked on the 5.8uF cap. It definitely gets the clean and tidy vote.

So all of them are correct? In that picture the 2.7 is piggybacked, in others it's in the original "B" and "G" slots (for lack of a better word) and the 5.8uF cap is in the "H" and the slot by the "R2" position. Are both of these methods correct?

heiney9

audiocr381ve wrote: »

I want to know why people chose to do it different ways. Which way is correct for my pin/blade SDA-2B version?

Confused in San Diego,
Shane

Perhaps you shouldn't be doing this if you are asking such questions.

They choose to do it different because everyone's visual skills are different. They are all correct. Read the threads and pick a path, or let someone else do it for you. You have all the info here to make the correct choices. If you can't apply or process the info given then it's time to pass this project on to someone who can.

Not being mean, just stating the facts. If you are this confused when you basically have everything spelled out for you, then it's just beyond your scope. No shame in that. The shame comes when you never realize you might be in over your head and you continue on anyway.

H9

heiney9

audiocr381ve wrote: »

So all of them are correct? In that picture the 2.7 is piggybacked, in others it's in the original "B" and "G" slots (for lack of a better word) and the 5.8uF cap is in the "H" and the slot by the "R2" position. Are both of these methods correct?

Atleast now you are asking specific questions..........before you said something vague like "why is everyone doing something different with the 2.7 resistor"?

I had no idea what you meant, physically, changing the value, putting in a different spot than the schematic?????

Now atleast you're asking specific questions and you will get some answers.

Just tagging 3 photo's and asking which is correct won't get you anywhere.

H9

audiocr381ve

heiney9 wrote: »

Perhaps you shouldn't be doing this if you are asking such questions.

They choose to do it different because everyone's visual skills are different. They are all correct. Read the threads and pick a path, or let someone else do it for you. You have all the info here to make the correct choices. If you can't apply or process the info given then it's time to pass this project on to someone who can.

Not being mean, just stating the facts. If you are this confused when you basically have everything spelled out for you, then it's just beyond your scope. No shame in that. The shame comes when you never realize you might be in over your head and you continue on anyway.

H9

Harsh dude!

I have a problem with assuming people know what I'm trying to ask. My wife hates this about me. Every time I tell her a story she has to ask a hundred questions because I don't articulate what my brain is thinking very well and I assume she knows what I haven't even explained!

Sorry guys, my fault on not being specific. BTW H9, haven't you seen what I've done already? I'm actually quite proud of myself for getting this far :cool:. I just installed the new RD0-198's, bought a desoldering gun which made for clean removal of the old parts, soldered the 2.7 ohm and .5 ohm Mills resistors in place, got the 5.8uF Cap installed and looking good with some hot glue to hold it in place. I went to bed stoked to have learned so much more during this build. Pass it on to someone who can? Pshhh. Do it myself and make some mistakes along the way is how I've always learned things.

Again, just double checking here with this next question. Take a look if you would at the attached pictures and let me know if what I did was correct. Thanks guys.

On3s&Z3r0s

I think it's a valid question whether they're all correct, and I'd say they all look correct from the 30,000 foot view. Personally, to convince myself, I'd have to look at the PCB traces on the back of the board and compare them to the schematic before I got heavy into glue and solder. There's a lot of holes in the board that go unused for the 2B's so I'd want to doublecheck myself that the leads were in spots that were electrically correct for the circuit. I think the advantage of the third sample pic is that it looks like the simplest mounting, and since you've got fewer leads crossing (like the small inductor, 2.7 Mills, and 5.8 cap all clustered together in your first pic) there's less chance that something will accidentally come into contact and short. Just my 2 cents, tho, I agree they all should work if you're careful.

EDIT: our posts crossed... if you've already got the 5.8 cap and 2.7 resistor soldered I wouldn't change them. Might not even be an option of you've already clipped any of the leads. The .5 ohm resistor looks right to me.

heiney9

Not trying to be harsh. I will not give advice to an extremely general question. It's impossible. Looks like you are making nice progress and you are doing it the correct way, slowly and asking specific questions.

H9

Joe08867

After looking at the pics it looks like you are on the right track.

My boards were different but if I were doing this on your boards the third pic in post 73 is the method I would have used.

You may need to set the caps on there sides to fit them to the board with the resistor there now though.

aviator

audiocr381ve wrote: »

Harsh dude!

I have a problem with assuming people know what I'm trying to ask. My wife hates this about me. Every time I tell her a story she has to ask a hundred questions because I don't articulate what my brain is thinking very well and I assume she knows what I haven't even explained!

Sorry guys, my fault on not being specific. BTW H9, haven't you seen what I've done already? I'm actually quite proud of myself for getting this far :cool:. I just installed the new RD0-198's, bought a desoldering gun which made for clean removal of the old parts, soldered the 2.7 ohm and .5 ohm Mills resistors in place, got the 5.8uF Cap installed and looking good with some hot glue to hold it in place. I went to bed stoked to have learned so much more during this build. Pass it on to someone who can? Pshhh. Do it myself and make some mistakes along the way is how I've always learned things.

Again, just double checking here with this next question. Take a look if you would at the attached pictures and let me know if what I did was correct. Thanks guys.

audiocr381ve,

Keep working on it and you'll get there, it may or may not be the shortest way there, but you'll get there and that's all that counts..

inspiredsports

All of the various architectures you've found were utilized to fit larger modern components onto a board that was laid out with mid-eighties components in mind, and all are correct.

The backside of the circuit board makes many connections that folks have skipped and gone point to point, in other words, they've "simplified the equation".

Removing the original 2.7 ohm "sand" resistor that was originally standing vertically just to the right of "C5" (where the new 5.8uf bypass cap is to be placed), and sharing the same two small holes above and below the rectangle drawn on the board delineating "C5" for the leads of both the 5.8uf cap and the 2.7 ohm Mills resistor makes for the cleanest installation. Cap first with the larger surface area of the cap hot glued to the board for support makes the most sense. Don't overdo the glue, but be sure things are secured from vibration as stability is important considering the components share the same space as the drivers.

As Jeff stated, your new components are non-polar so orientation is not an issue.

audiocr381ve

inspiredsports wrote: »

All of the various architectures you've found were utilized to fit larger modern components onto a board that was laid out with mid-eighties components in mind, and all are correct.

The backside of the circuit board makes many connections that folks have skipped and gone point to point, in other words, they've "simplified the equation".

Removing the original 2.7 ohm "sand" resistor that was originally standing vertically just to the right of "C5" (where the new 5.8uf bypass cap is to be placed), and sharing the same two small holes above and below the rectangle drawn on the board delineating "C5" for the leads of both the 5.8uf cap and the 2.7 ohm Mills resistor makes for the cleanest installation. Cap first with the larger surface area of the cap hot glued to the board for support makes the most sense. Don't overdo the glue, but be sure things are secured from vibration as stability is important considering the components share the same space as the drivers.

As Jeff stated, your new components are non-polar so orientation is not an issue.

Awesome, thanks guys.

Could any of you that are familiar with the SDA-2B board give feedback to post #78?

gimpod

audiocr381ve wrote: »

Awesome, thanks guys.

Could any of you that are familiar with the SDA-2B board give feedback to post #78?

Your good to go. Also in the pic in post# 72 where the lead from the 5.8uF cap cross's over the lead from the inductor you should put something (non-conductive) between those two leads to insulate them from touching one another.

Also I have to agree with H9, The next time you decide to do something like this you should go to the library and check out a book on basic electronics at least and not to put to fine of a point on it but you have been asking some pretty basic questions on basic electronics that anybody with a rudimentary understanding of electronics should know. Just my $0.02

inspiredsports

Your images in post #78 are correct.

audiocr381ve

gimpod wrote: »

Your good to go. Also in the pic in post# 72 where the lead from the 5.8uF cap cross's over the lead from the inductor you should put something (non-conductive) between those two leads to insulate them from touching one another.

Also I have to agree with H9, The next time you decide to do something like this you should go to the library and check out a book on basic electronics at least and not to put to fine of a point on it but you have been asking some pretty basic questions on basic electronics that anybody with a rudimentary understanding of electronics should know. Just my $0.02

Awesome, thanks Gimpod. I'm a hands on learner. Checking out a book would get me no where, fast (plus, does anybody go to the library anymore?). The questions are gonna be rudimentary because I literally need to learn the basics (don't we all at one point?), and the web is very misleading/confusing at times. The cool thing is I will have completed both crossovers, something I'm absolutely not qualified to do, by Tuesday. What have I learned? A lot. So a big thanks! 2nd time around it'll be a lot different.

inspiredsports wrote: »

Your images in post #78 are correct.

Thanks! I'm 90% done, super excited about finished this.

audiocr381ve

It all goes down tonight. Can't wait.

I just got the JB Weld. Stupid question but which tube do I use? "Hardener" or "Steel" ?

nspindel

I've never used the stuff, but my money's on mixing the two together. You might wanna read the directions...

audiocr381ve

You are correct. My excitement blinded me for a moment.

nspindel

Take a deep breath, and do this stuff slowly, carefully, neatly, and meticulously. You're spending minutes and hours of time building something that you'll be enjoying for months and years. Don't let the "OMG, I can't wait to listen to this!" emotions get the best of you. You're working with expensive materials. Do not rush this.