SDA 1B Crossover Upgrades/General Thoughts

WastelandWand'r

After sneaking around trying to ask questions of some of the 'elders' on the sly, it was suggested I throw a question out into the deep end of the knowledge pool.
Purchasing a set of what looks to be a well kept pair of 1B's (Studios? (85lbs)).
I have tried to search for a thread of a previous upgrade to the XO or to the set in general with no luck. Anyone out there have experience with these?
If you have a link, shoot it my way.
Any help, ideas, greatly appreciated.
Oh and greetings form the edge of nowhere.
Nathan

jon s

most of the Polkies here recommend going with Sonicaps capacitors and Miller resistors. I had upgraded my Polk 10Bs to Jantzen caps but am now going to the Sonicaps to see what the differences are. The Sonicaps are well regarded for they price/performance ratio. Also, most Polkies suggest you stay away from Solen caps as they sound too harsh on the high end.

Face

http://www.polkaudio.com/forums/attachment.php?attachmentid=31011&d=1201824729

McLoki

Also if you still have the SL2000 (fisheye) tweeters, it is well worth the upgrade to the RDO-194 replacement tweeters from polk. (tell them you are a club polk member and the price is $48 shipped per tweeter)

The 1b's are a rockin speaker and well worth the time, effort and money to upgrade.

Michael

WastelandWand'r

McLoki wrote: »

Also if you still have the SL2000 (fisheye) tweeters, it is well worth the upgrade to the RDO-194 replacement tweeters from polk. (tell them you are a club polk member and the price is $48 shipped per tweeter)

The 1b's are a rockin speaker and well worth the time, effort and money to upgrade.

Michael

Many thanks. And sorry for the delayed reply.

I say purchasing, but from photos provided, it would appear to be the old silver eyes. I just finished with a modest upgrade on my original 10's with XO work and RDO-194's installed. Could not with my ears, (too many Judas Priest Concerts) tell the difference with just the XO fix, at least until the new tweeters were installed. Not nearly as 'hissy/spitty' as the old ones.

Schematics and I are worlds apart. Lets just say I challenged no one for the Valedictorian status!!

Does any one have a parts list? I can take it from there using other threads for ideas on positioning the caps and other items.

Again, thanks for the help.
N

F1nut

Nathan, good to see you posting.

Complete list for both speakers.

Caps:
(2) 4.4uF
(2) 12uF
(4) 34uF
(2) mystery, could be 85, 83, 65, 63, 55 or 53uF. Just can't make it out on the schematic. Check with Polk.
(2) 130uF

Resistors:
(2) 2 ohm
(6) 2.7 ohm

Forget replacing the (4) 750pF bypass caps, just remove them as they are no longer needed.

WastelandWand'r

F1,
Got it. I will let you know how it shakes out.
Thanks everyone.
N

polktiger

WastelandWand'r wrote: »

F1,
Got it. I will let you know how it shakes out.
Thanks everyone.
N

Post back how it shakes out. I have the same speakers and like you always see threads on mods to other models, but rarely the 1Bs. It also sounds like my ears are in the same shape as yours. I still can't believe I would crank the walkman loud enough with Metallica so it would drown out the sound of the lawn mower while cutting the grass as a summer job. (Boy was I stupid!)

heiney9

My 1C's with the RD0 tweeters and Sonicaps sound absolutely fantastic!! Well worth the investment and effort. I see you live in Alaska, I'm sure postage isn't cheap but you won't be disappointed in going this upgrade route.

H9

george daniel

You know,, with the sonicaps and the replacement tweeters,you will be go to go for another 15-20 years with those speakers.I believe that you have the foundation,so to speak for an outstanding 2 channel rig, for not a whole lotta $$$$--good luck,have fun and enjoy.

dcmeigs

Hey Nathan,

Welcome. Glad to see you posting here.

If you have those shipped here, give me a shout. I'd be happy to go have a look at them for you, check out the drivers and take some pics of the crossovers.

Jessie, that looks like a 65 uf cap. If so, a total of 195 uf x 2. That's going to be a bundle of cash in sonicaps. I'm thinking that one might consider going with a SDA-1C crossover design even if it meant replacing a few of those 20 year old drivers. Do you happen to know which drivers the 1B uses?

Dave

Face

You can always go with cheaper caps on the LF circuit instead of changing the design on the speaker. $40 per speaker using PE's Dayton caps.

dcmeigs

Face wrote: »

You can always go with cheaper caps on the LF circuit instead of changing the design on the speaker. $40 per speaker using PE's Dayton caps.

True dat.

I note the inductors are different too. Best stick with the hand delt.

WastelandWand'r

DC,
Well the deal is done and took delivery of them today. Well, I paid for them and am now working on getting them to your neck of the woods. This will take a while and they will live in someone elses home for the next few years, unless I feel the uncontrolable urge and send them here. Time will tell.
On my next trip down there, I will let you know when I am in the area and let you see them. That and I may need a local sounding board if a gremlin rears its head.
I will order the parts and have them waiting. Give me something to do if family becomes too much. Visiting 4 sisters can do that to a guy.
I will look into the Dayton/Sonicap combo for price diff.
N

F1nut

Ok, I'm confused. You bought the speakers, but you're having them shipped elsewhere and won't actually have them for a few more years???

WastelandWand'r

F1,
I apologize. I should have let everyone know that I sometimes do things that at first blush may sound a little crazy, or not seem so uhmmm.... normal.
Yes, they are going to a relatives house and I will only get to visit them for the next few years until I leave the comfortable confines of the 49th state. Where I live now, the A/C comes from very unreliable diesel powered GENERATOR's. (Voltage swings are a daily occurence, along with the associated power outages) So I won't bother bringing them out here. They will be upgraded and give someone else great listening until then.
I travel there quite a bit, so it isn't as bad as it seems. Well actually it is, but we do what we have to do.
Make sense?
My significant other has grilled my quite a bit about this one.
So until then, Monitor 10B's it is. (Upgaded XO and the 194 tweeter)
N

McLoki

Have you thought about running your audio system off a ups? At least that should smooth out the AC signal they recieve. There are a number of them available that shoudl help with massive swings in AC voltage. To get a decent one won't be cheap, but at least you can enjoy what you own for awhile. Purchase used and you can sell them when you don't need them anymore for a minimal (if any) loss.

Just a thought,

Michael

Face

http://www.amazon.com/Belkin-PureAV%C2%AE-Theater-Technology-AP30800fc10-BLK/dp/B000T9DHZ2/ref=pd_bbs_sr_11?ie=UTF8&s=electronics&qid=1215269318&sr=8-11

http://www.amazon.com/Belkin-HYBRID-AVU1500-UPS/dp/B000IZWTQU/ref=sr_1_17?ie=UTF8&s=automotive&qid=1215269337&sr=8-17

F1nut

Ok Nathan, thanks for the more detailed explanation.

I have to say that the speakers are the last thing I would worry about getting damaged from dirty power or power loss. You would be perfectly fine running the SDA's just as you have run the 10's.

You might want to look into getting a PS Audio power regenerator. An excellent product for your situation.

WastelandWand'r

My main concern isn't damage, just bringing them here to move them again in the near future at considerable expense!!!! It will be expensive enough to move them to Washington state.
Also, I figure they ain't making them anymore so why not get them? Gotta do my part in stimulating the economy.
So, I will continue to make plans for them and can't wait to lay my hands and ears on them.
Now, I need to work on suitable amps for them.
N

F1nut

Gotcha.

WastelandWand'r

If anyone out there is interested, spoke with Polk Tech's and they confirmed from their 1B schematics that the mystery cap value wired in parallel with the 130 is a 55uF. Didn't want anyone laying awake at night losing sleep over it.
N

WastelandWand'r

All right, something new. Just received an e-mail follow up. Now it is being identified as a 65uF, not the 55.
It has been a learning process for me.

Boywonder

Is there any chance that these speakers are actually 1C studios? Are they walnut (brown) vinyl or ash (black) vinyl? The reason I ask is that my 1C studios say 1B on them (and the manual) but have the one piece crossover PCB instead of the 2 pc crossover thats in the 1B and early 1C's.

If they happen to be 1C's and have the 1 PCB crossover, the component values are different from the 2 board crossover of the 1B.

Checking P/N's on the back of the mid woofers would also confirm their identity.

WastelandWand'r

Boywonder,
PM sent.
N

WastelandWand'r

Here they are.
Attachment not found.

Sorry for the quality.
Sl 2000's, MW6509's, SW120.
N

Boywonder

Question for the Experts: These appear to be wood veneer instead of vinyl. Is this rare or fairly common for 1B's?

F1nut

Common.