SDA-1C Crossover upgrade - Journey Begins

thsmith

I ordered the following parts today from Sonicraft to upgrade the CAPs and resistors in my crossovers so I thought I would start this post to document my journey.

I realize many others have taken this path before me and I have read many of those post as well.

I am probably overly cautious doing this but I would be sick if I did anything to negatively impact the sound of my SDAs.

I am doing this for piece of mind more than anything because I love how my speakers sound.

Parts ordered:
-Replace the 12uF caps with Sonicap Gen1.
-Replace the 4.4uF (This custom value will cost the same price as a
4.7uF) caps with Sonicap Gen1.
-Replace the 20uF caps with Sonicap Gen1.
-Replace the 40uF caps with a Aeon (Axon) 41uF. Unfortunately, they are not listed on our site.
-Replace all the resistors with Mills MRA-12s.
-Use Cardas Quad-Eutectic solder
-Remove the small silver mica caps and the polyswitches.

I was not sure if I needed 2 or 4 .5 ohm resistors in place of the polyswitches so I ordered 4. If I only need 2 I will karma the remaining 2.

I have a friend who has access to some single layer Printed Circuit boards so I can start practicing desoldering and soldering, also to find the right clamp/mount to hold the CP board.

Right now all I have is a pencil soldering iron. I would like feedback on if this will work or a recommendation for something better.

I have soldered before but mostly wires and carver lamps not CAPs and resistors.

I will be posting pics and updates once I get started.

I definately have to thank all of the people before me that posted their journey and the private PMs I have received offering to help which is just simply amazing to me. My confidence is growing.

thsmith

OK, a few changes. After taking with Mr. Daniels(Thank you George) and I learned I need just 2 of the .5 ohm resistors and for the 40uF I decided to go with Sonicraft 2x20uF caps. Maybe overkill but like I said I am doing this for piece of mind.

I love Polk Audio and CLub Polk;) , I swear its better than Harley Davidson's.

F1nut

Right now all I have is a pencil soldering iron.

Yep, exactly what's needed.

You'll also need a solder sucker.

kawizx9r

Hey thsmith, question; do you have RD0's already inside your 1C's?

I've had 2 friends tell me I should do redo the crossover for sure, and have received that same recommendation on here. Thing is, I did get a few that recommended I do the RD0's first. Wondering what everyone else's thoughts are and yours as well once you're done with your mod. Keep in mind, I don't find the stock SL2000's harsh at all if that helps....some people do and some people don't. Goodluck with your mod!

thsmith

kawizx9r wrote: »

Hey thsmith, question; do you have RD0's already inside your 1C's?

I've had 2 friends tell me I should do redo the crossover for sure, and have received that same recommendation on here. Thing is, I did get a few that recommended I do the RD0's first. Wondering what everyone else's thoughts are and yours as well once you're done with your mod. Keep in mind, I don't find the stock SL2000's harsh at all if that helps....some people do and some people don't. Goodluck with your mod!

I changed out the tweeters first for 2 reasons, 1 is that it is the easiest to do and 2 when I changed out the tweets on my Monitor 12s it made such a huge difference. This is not exactly an apples to apples comparision because the M12s use 198s which made a bigger improvement than the 194s on the 1Cs.

Definately worth doing on the 1Cs.

Adding myesound spikes to my 1Cs made a big difference too. And of course cables made a big difference to but that is for another thread.

I am mainly replacing the caps and resistors for piece of mind due to age and if the SQ is better then that is icing on the cake.

I feel like I am finally getting to a decent baseline with equipment and cables so the XOs are the next logical step for me.

tx_polkhead

You know you are in my neck of the woods, I would offer to bring over some beers just to watch the process but then again beer and solder don't mix!
Abel

thsmith

F1nut wrote: »

Yep, exactly what's needed.

You'll also need a solder sucker.

Great ! I do need to get a solder sucker, I will add that to the list. Thanks !

thsmith

tx_polkhead wrote: »

You know you are in my neck of the woods, I would offer to bring over some beers just to watch the process but then again beer and solder don't mix!
Abel

Abel, would be glad to have the extra set of eyes.

Conradicles

thsmith...I did one of my crossovers today, and will do the other tomorrow. Very simple. Pretty fun too. What a cool hobby we have!

thsmith

Kewl, I will follow in your digital dust;)

thsmith

I sent Conradicles this in a PM but since my caps and resistors are to arrive today and being I am impatient I thought I would ask here too.

I plan to use 2 20uF Soniccraft wired in parallel to replace the 40uF, this is correct right?

How did you mount the 12uF (one sitting on the corner of the PC board) ? I see in some pics people mount it standing on end with a piece of wire soldered to for extention, if you did this what size wire did you use?

inspiredsports

while not a 1C crossover, I believe the photos in POST # 54 will help you out a bunch . . .

http://www.polkaudio.com/forums/showthread.php?t=74945&highlight=crossover+parts+list&page=2

thsmith

Thanks, searching the web I found out for sure and talked to a couple of EEs at work that paralleling 2 20uFs equal 40uF. I knew this but started doubting my self.

I did buy 22ga solid conductor just in case I need to extend the cap lead on the 12uF.

Parts arrived today. So on to taking pics and making sure I know what I am doing.

george daniel

maybe this will help

F1nut

How did you mount the 12uF (one sitting on the corner of the PC board) ?

That's not a 12uF on the corner, that's the 40.

I found it easier to use a 30 mounted on end, on top of the board and a 10, mounted under the board.

thsmith

F1nut wrote: »

That's not a 12uF on the corner, that's the 40.

I found it easier to use a 30 mounted on end, on top of the board and a 10, mounted under the board.

AH HA ! Thanks F1.

thsmith

Thanks George, the pics were a big help. Here are some before and after pics. 1 down and one to go. I have sound in stereo and dimensional.

F1nut

Might I suggest using a little hot glue to help hold those caps to the board and also to aide in damping.

thsmith

All done !. Thanks to F1, George D and Conradicles for the help and support.

The PC Board has names and numbers for the replaced parts so I thought I would capture them here.

C1 - 20uF
C2 - 40uF
c3 - 12uF
C4- 750pF ( I removed this)
C5 - 4.4 uF
S1 - Polyswitch (replaced with .5 ohm)
R1 - 2.7 ohms
R2 - 7.5 ohms
R3 - 7.5 ohms

I used hot glue to mount the caps.

Now to do some listening, good news is I can do some listening.

I will update this thread over the next coming weeks on any sound changes but what I immediality notice are the vocals are further back now and in line with the main instruments, more pronounced mid bass.

thsmith

F1nut wrote: »

Might I suggest using a little hot glue to help hold those caps to the board and also to aide in damping.

Yep I did that and where I stacked the 20uF I used hot glue to hold both of them together and on the 20uF and 12uF cap.

Very rewarding upgrade.

F1nut

Ah....sorry, I didn't see any.

Enjoy!

thsmith

No worrys, I saw in a couple of other post that you recommend doing that and it make sense. I dry fitted first and then put a nice bead of hot glue down, mounted and after a few minutes soldered them.

The Cradas solder flows nice. I used a wick to remove the solder. Worked very well.

Thanks again for the help.

Going back and looking at Georges pics I did not put hot glue on the 2 20uF on the coil side, just the board and between the caps.

Think it would be a good idea and add hot glue there too ?

george daniel

Just my .02,, I put enough hot glue on mine to withstand a 3 foot drop,, paying special attention to the 2 twenties--looks like you did a fine job, how do they sound?IIRC, you'll need to put a couple-three hundreed hours on em'.(less time if using a tube amp) JK--enjoy--good work.;)

thsmith

Thanks George, I think I will add some glue to the voice coils too.

Initially I notice the vocals are further back now and in line with the main front line instrumentswhich I like as I thought the focals where a lot more forward than they needed to be, more pronounced mid bass.

I will be leaving the radio going overnight and days when I am not using the system.

Again, thanks to all you guys that have blazed the trail.

TRacy

Face

thsmith wrote: »

Thanks George, I think I will add some glue to the voice coils too.

You mean inductors right?

george daniel

Face wrote: »

You mean inductors right?

yes ,, it too early,,lol,, thanks for correcting me/that

Ron Temple

Nice job Tracy...it's starting to give me confidence that I might be capable...though I have trouble fixing my sprinkler system. Let me know what it does for your treble. If it sweetens up the highs, then I'm going to be all over this. I've been hearing some speakers lately that cast a shadow on my 1Cs in the tweeter area. Looking for better control and a sweeter tune even on dissonant material. You probably won't notice improvements there from what I've read, until they get some hours on them. Keep me posted.

thsmith

Ron, If I can do it anyone can but the key is many people have went before us and are willing to help bring others along. That is the greatest part of CP.

I just got through listening to some Jayhawks which has alot of acoustic guitar, had it pretty loud and almost fell asleep, it was so relaxing and soothing.

I am enjoying the differences. I don't like bright but I do like detail. Also I always felt the male vocals were almost in your face on my 1Cs. Not now.

I am pleased. If it helps to get you going I will send you some of the left over Cardas solder I have, I am impressed how nicely it flows.

Also, I did not have a bulb/sucker for desoldering and watched a few videos on using them. I have to say I like the wick method but the other methods may be better I was just more confident using a wick.

Can't find any Dynamat extreme at Best buy or Frys so I need to order some but I did add more hot glue as suggested above.

Something else I bought was a B&D rechargable screw driver that you can adjust how much touque to apply to the screws for the speakers so as not to strip them. Seems handy and make taking out and reinstalling the PR quick. It was $19 at Homedepot.

Face

The RD0-194/8 doesn't give much up compared to many today's high end tweeters. In your case Ron, the crossover is holding it back. Be sure to use some good caps in the HF section(Claritycaps, etc...), and you'll have a different speaker. There are plenty of upgrade threads here, and most have pictures. If you still feel you can't tackle it, there's a few here who could help you out.

thsmith

With 40 hours of burn in I am really enjoying to improvements in all aspects of sound. THe highs have higher level of clairty and detail. The mid-bass is so smooth and tight and the bass is deep and tight. Sound stage deeper and wider.

Took a page from DarqueKnight and replace the stock grill cloth with Ponte Knit Cloth from Hancock Fabrics. The difference is like listening with the grills off.

PSOVLSK

thsmith wrote: »

Ron, If I can do it anyone can...

I'm going to have to disagree with you Tracy:p:D:D I'm about to take the "spike those suckers" advice and I'm nervous about it.

Looks like you did a great job. Glad to hear it was a worthwhile investment of your time and money. Sounds like you're really enjoying the upgrade. I've got to get back over there and hear your system since you've spiked them and changed out the XO's. I thought it sounded incredible BEFORE these upgrades...not to mention the new IC's and speaker cables.