Help to uppgrade Polk Audio sda 2

trosse1

Hello, sorry for my English, I use google translator.

Are new to the forum and need some help.
Having recently bought a gorgeous pair of polk sda 2, I want to upgrade the crossover, do not want to disassemble the speakers until I have new parts at home.
Do that several sonicap recommends:

this is the right part of my crossover?

SDA 2
.5 UF capacitor
12uF capacitor
12uF capacitor
27uF capacitor
27uF capacitor
2.7 ohm resistor
2.7 ohm resistor
3.5 ohm resistor
3.5 ohm resistor
.4 MH inductor
.4 MH inductor
1.82mH inductor
1.82mH inductor
11.2mH inductor

What generation sonicap recommended - gen1 200vdc /gen1 600vdc / gen2 or platinium ??


My dealer has not sonicap with appropriate specifications,
Can i use :

0.5 UF capacitor = Sonicap 0,047uF ?
27uF capacitor =Sonicap 30uF ?

http://www.upgradeaudio.com/index.php?visKategori=67

Other parts of the filter that should be replaced?

In advance, thanks for your help here in the north Norway

dudeinaroom

The 30 in place of the 20 should be close enough. 0.5 UF for the 0.047uF...no way! A .05 should be close enough.

gimpod

Welcome to Club Polk and the never ending rabbit hole,

I hope your wallet is nice and fat because it won't be if you stick around here for very long.:cheesygrin:

If you want to go with Sonicap's just order them direct from Sonic Craft they'll do international orders and have the values you need and are having a 20% off sale going on till the 31st.

Sonicap Gen 1's 200vdc are the ones to get, I would also go with Mills 12 watt resistors also available at Sonic Craft. I would forget about replacing the inductors for that model of SDA as they are impossible to find good replacements.

If I were you I would pull the crossover and double check the capacitor and resistor values before your order. The schematics will get you in the ball park but may or may not match what you actually have.

Good luck on your journey down the rabbit hole.

Schurkey

trosse1 wrote: »

0.5 UF capacitor = Sonicap 0,047uF ?

You currently have a 0.5uF capacitor. The 0.047 is NOT suitable. There's a factor-of-ten error. A 0.47uf could be (just barely) satisfactory.

trosse1 wrote: »

27uF capacitor =Sonicap 30uF ?

I would look for something closer. The generally-accepted tolerance is to be within 5% of the nominal rating, which in the case of the 27uF cap would be 1.35uF. A 28uf or a 26uF cap would be reasonable, a 30uF is a bit too far out of range.

dudeinaroom wrote: »

0.5 UF for the 0.047uF...no way! A .05 should be close enough.

As I understand it, he's got a 0.5uF, and asked about using a 0.047uF to replace it with. Not the other way around.

PolkieMan

Use your original inductors.
Sonic cap makes a 27 look here.
http://www.soniccraft.com/sonicaps.htm
Get in on the 20% off sale before 10/31.
Just pick what need and email them for a quote they will get back to you within 24 hours.

westmassguy

Welcome to Club Polk. Use the Sonicap Gen I for the Hi-Pass only, the 12ufs and the .5ufs. The 27uf caps are part of the Low-Pass, 2nd order bypass circuit, and do not need to be Sonicaps. Any quality, 5% Metalized Polypropylene cap will do, such as Dayton, Bennic, Solen, etc. You'll save some money there.
Use Mills 12 watt resistors in place of the original sandcast resistors. Leave the inductors alone, but check to make sure they're secured properly. The nylon wire ties are frequently loose of broken, and the hot glue may be falling off.
If your 2s have external Tweeter Fuses, clean and polish the fuse holders, apply some DeoxIT, and install new "Fast Blow" fuses.
If you have internal Polyswitches protecting the Tweeters, consider replacing them with either new Polyswitches available from Polk Customer Service, or do what most do around here, and install either .2 or .5ohm Mills resistors in their place, providing you have quality amplification.
Contact Elliot over at Sonicraft, he'll get you squared away with the Sonicaps and Mills, and as PolkieMan said, they're on sale till the 31st

trosse1

Thanks for the help everyone.

I order Sonicap Gen 1-200Vdc 12ufs and 0.5ufs + Mills 12 watt resistors, and buy a cheaper manufacturer 27Uf.

I opened up today and component list matches my crossover.

I have marked in red three components - what is it? buy new or just set back?

Having selected two blue components with yellow-what is it? should they be replaced?

Westmassguy : points tveeter protection - external Tweeter Fuses / or internal polyswitch Protecting - where will I find the protector?

nspindel

The items you've circled in red are bypass caps. With Sonicaps you no longer need bypass caps, so just forget about them. The blue piece you've circled in yellow is the polyswitch, which most people doing crossover mods remove. There is endless debate over whether you should just replace with a wire jumper or with a 0R5 resistor. In my 4.1TL's I used a 0R5 resistor. Good luck!

trosse1

And this little thing

nspindel

Hmmm, I've never seen that guy before. Looks like a resistor but I wouldn't bet my life on it.

pitdogg2

without a better picture of that without all the RED lines I'm going out on a limb here, but to me it looks like the date sticker of when it was made.....way out on a limb

you may also need to take that .5 ohm cap off that resistor to get the value of that resistor to be positive.

nspindel

Hahahah! Yes, looking at it more closely I agree.

trosse1

3,5 ohm resistance

bad joke :-))

PolkieMan

The 27uf caps are part of the Low-Pass, 2nd order bypass circuit, and do not need to be Sonicaps.
Any quality, 5% Metalized Polypropylene cap will do, such as Dayton, Bennic, Solen, etc.
You'll save some money there.
I did not know that, call me overkill.


Sonic caps 27?F / 200VDC 1.41 x 2.76 $40.04 x 2= 80.08 - 16.16= $63.92 20%off That's not too bad

I would go Mills on the resistors
http://www.soniccraft.com/mills_resistors.htm
Polyswitch if you want
http://www.parts-express.com/cat/polyswitch-resettable-fuses/1433

westmassguy

PolkieMan wrote: »

The 27uf caps are part of the Low-Pass, 2nd order bypass circuit, and do not need to be Sonicaps.
Any quality, 5% Metalized Polypropylene cap will do, such as Dayton, Bennic, Solen, etc.
You'll save some money there.
I did not know that, call me overkill.


Sonic caps 27?F / 200VDC 1.41 x 2.76 $40.04 x 2= 80.08 - 16.16= $63.92 20%off That's not too bad

I would go Mills on the resistors
http://www.soniccraft.com/mills_resistors.htm
Polyswitch if you want
http://www.parts-express.com/cat/polyswitch-resettable-fuses/1433

Look at the schematic for a simple, 2nd order crossover : http://www.colomar.com/Shavano/crossover12db.html
You'll note in the Hi-Pass section, the Capacitor is in Series with the driver. This means that the actual music signal supplied by your amplifier passes through the Capacitor first, then on to the driver. The Inductor is in Parallel with the driver and is acting as a bypass or shunt. This helps the Capacitor by bleeding off low frequencies before they reach the driver.
In the Low-Pass section, the opposite is true. The Inductor is in Series with the driver, so the music signal passes through it first then on to the driver. The Capacitor is in Parallel with the driver, and helps the inductor by bleeding off high frequencies before they reach the driver.
In both cases, the component that's in Series with the driver, should be the best quality you can afford.
The component that's in Parallel, and Before the driver can be of lesser quality, since you don't actually hear any of the music signal that's passing through it.
That's why manufactures can get away with using Bi-Polar or Non-Polarized Electrolytic Capacitors in the Low-Pass section. The problem with Electrolytics, is lifespan. As they age, the Electrolyte dries out or leaks out causing the capacitance value to drift, and the capacitor will eventually fail completely.

PolkieMan

Wow Wow! This is some great information from you and this website thanks for your time and pointing me in this direction!

westmassguy wrote: »

Look at the schematic for a simple, 2nd order crossover : http://www.colomar.com/Shavano/crossover12db.html
You'll note in the Hi-Pass section, the Capacitor is in Series with the driver. This means that the actual music signal supplied by your amplifier passes through the Capacitor first, then on to the driver. The Inductor is in Parallel with the driver and is acting as a bypass or shunt. This helps the Capacitor by bleeding off low frequencies before they reach the driver.
In the Low-Pass section, the opposite is true. The Inductor is in Series with the driver, so the music signal passes through it first then on to the driver. The Capacitor is in Parallel with the driver, and helps the inductor by bleeding off high frequencies before they reach the driver.
In both cases, the component that's in Series with the driver, should be the best quality you can afford.
The component that's in Parallel, and Before the driver can be of lesser quality, since you don't actually hear any of the music signal that's passing through it.
That's why manufactures can get away with using Bi-Polar or Non-Polarized Electrolytic Capacitors in the Low-Pass section. The problem with Electrolytics, is lifespan. As they age, the Electrolyte dries out or leaks out causing the capacitance value to drift, and the capacitor will eventually fail completely.

westmassguy

PolkieMan wrote: »

Wow Wow! This is some great information from you and this website thanks for your time and pointing me in this direction!

You're welcome. Keep in mind, I gave a very simple example, and used terms that are easy to understand. The crossovers Polk designed and built for their vintage Monitors and SDAs go from simple to very complex. The SDAs are very complex in most models, and there's more going on than just separating the frequencies and sending them to the proper driver. In any event, as I mentioned earlier, the components that are in Series with the driver should always be the best quality you can afford. This includes Resistors as well.

trosse1

Hello again, this is the best option to replace the tweeter in my speakers? and the most inexpensive price.

http://www.ebay.com/itm/Replacement-Tweeter-for-Polk-Audio-SL-1000-8-ohm-Tweeter-MT-4115-8-/150791478865

Or are there better options.

westmassguy

trosse1 wrote: »

Hello again, this is the best option to replace the tweeter in my speakers? and the most inexpensive price.

http://www.ebay.com/itm/Replacement-Tweeter-for-Polk-Audio-SL-1000-8-ohm-Tweeter-MT-4115-8-/150791478865

Or are there better options.

The correct replacement for your SL2000 tweeters is the RDO-194, available directly from Polk. Call Polk Customer Service, Tell them you're a member of Club Polk, and they will cost you $48.00 each. For US customers they ship free, not sure about overseas.
The Tweeter you linked to is a replacement for the old Peerless Tweeters, and is NOT compatable with your SDA-2

trosse1

When the parts are here, do not change old 27uF capacitor.

westmassguy

trosse1 wrote: »

When the parts are here, do not change old 27uF capacitor.

Are you asking whether you should change the 27uf Low-Pass Capacitor, or are you saying you won't be changing it?
You've gone this far, it makes no sense not to change it. You don't need to use the more expensive Sonicaps for that Capacitor.
Dayton, Bennic, Solen metalized polypropylenes will do just fine as replacements.