SDA 1C....who knew?

[Texas42]

Just bought and brought home AVGuyTX's (thanks Kip!) modified 1Cs and hooked them up and have to admit; I'm geeked by them! I have a pair of 1Bs and they are also great in a two channel system but I think I like the silk domes in the 1Cs even a bit more. I'm still amazed about the sheer amount of full range, accurate, 3 Dimensional sound the old SDA speakers can reproduce. When you consider they sold for $1500-1800 new (Model 1's) and now can be had for as little as $350-400; they are an INCREDIBLE bargain! I'm just surprised a lot of people (other than this board) haven't figured this out...

[WilliamM2]

I knew.

[Marty913]

Getting a new pair of Polk's is great, isn't it. I too am amazed that people will spend multiple hundreds on speakers at Best Buy and Circuit City or thousands at Hi-Fi stores and usually not get half the experience a 20 year old set of SDA's can give them. Some of it I think is just the "new is better" philosophy, and some the decorating issues (larger speakers, not piano black, etc). I know for some of my friends, they just "didn't know".

Then again, do we really want them snapping up all the old Polk's?

[hoosier21]

This is a familiar line of thinking, 3 4 5 6 hundred for these old Polk SDAs, given the performance to price ratio, a frigging steal.

[avguytx]

Dave, I'm glad you like them as I was pretty sure you would! Like I mentioned, those crossovers have very little time on them and the tweeters "maybe" 4 hours. They will only get better as you break them in. I am glad someone in the forum got them that would enjoy them, too.

Dave is a great guy and no one should have hesitation in dealing with him.

[BobMcG]

Who knew??? :confused:
















Kidding!!! Have fun, enjoy 'em! :D:D:D:D

[hearingimpared]

1Cs are friggin awesome. Are your crossovers upgraded? If not, do it! You will not believe how much better it gets.

[Texas42]

Kip upgraded the crossovers with Solen caps and Mills resistors and changed out the tweeters to the RD0 silk domes; so everything is pretty much done. Verrrry smooth top end now (and the tweets just have a few hours on them so should smooth out even more). I'm very happy with them. I really enjoyed my 1Bs (which are now up for sale) but the 1Cs, with improvements, are even sweeter...

[zingo]

SDAs are a great value for the price. Although Marty913, there is one reason that some guys don't get a pair of speakers like this; the wife factor. Two huge, 80's monoliths tend not to fit in with modern design principles. Although, some guys on CP have done a great job working around that.

[Sami]

SDAs are a great value for the price. Although Marty913, there is one reason that some guys don't get a pair of speakers like this; the wife factor. Two huge, 80's monoliths tend not to fit in with modern design principles. Although, some guys on CP have done a great job working around that.

I know, my wife said he liked the DQ-10's looks better in our living room. Anyone who has seen the 10's know what their WAF is. She likes the sound though. :)

[hoosier21]

I know, my wife said he liked the DQ-10's ....

Interesting ;)

[Texas42]

Not that there's anything wrong with that....(Seinfeld)

[dbnh]

Nice to read the love for the 1Cs here. I have yet to replace mine (still hoping to get the crossovers done by a DIY friend one of these days; I did replace the tweets almost 2 years ago). I simply have found that I'd have to spend a considerable amount of change to get a significant improvement over what the 1Cs provide. As I've improved the rest of my system, the 1Cs have continued to sound better and better.

[heiney9]

As I've mentioned before I used to work for a high end (at the time) audio specialty store from about 88-90 and I was always amazed by SDA's. I always had a lot of fun demoing them for people and sold many sets of 2B's and 1C's after an awesome demo. Back then I awlays wanted a pair of 1C's but even at dealer prices they were too much for my college budget.

I sold a pair to my then girlfriend's parents just so I would have another place to listen to them besides work. After I left the store a good friend remained and he ended up getting a pair of studio 2B's for himself and his parents bought a pair as well so I still got to hear the SDA's on occasion.

Then there was a huge drought of SDA listening for me. Friends drift apart, girlfriends come and go, etc. and I figured owning a pair of what would now be used SDA's was a pipe dream. Joined the forum got my SDA "passion" aroused again and I luckily picked up a pair of excellent 1C's at the Illinois Polk-fest earlier this year. All the pieces (price, transportation, timing) fell into place. They have reworked x-overs and the RD0's.

They sound absolutely fantastic and still put a huge grin on face everytime I listen. IMO, the 1C's seem to have that perfect balance. If I had bigger SDA's they just wouldn't sound as balanced in my room. The 2B's are no slouch but I think the 1C's give just a little bit extra.

I will keep these forever (sorry local Polkies who have dibs)(pretty sure) even if I move to another main speaker.

H9

[MillerLiteScott]

Does anyone have the parts list for the 1C upgrade. I want to make sure I have all the right parts and pieces. I am still a little green with the crossover parts and pieces.

Thanks,

Scott

[avguytx]

You betcha...per the Compendium and verified when I did mine...err, Texas42's. :D What are you going to use? If you go with Solen caps and Mills resistors, I bought mine from PartsConnexion.com and have had great service from them for the 3 sets of SDA's I've redone the crossovers on.

For the tweeters: (amount shown is for left and right combined)
2) 12uf (they have a 750pf silver mica cap on the stock ones that I did not use or replace)
2) 4.4uf caps (I used 4.3uf)
2) 2.7-ohm resistors
4) 7.5-ohm resistors (2 per speaker)

For the woofers:
2) 20uf caps
2) 40uf caps

Ok. That's the stock part amounts. On the 40uf caps, I ordered (6) 20uf caps total and and 2 were wired in series to make a 40uf cap. YMMV. I do have a thread (http://www.polkaudio.com/forums/showthread.php?t=53503) with pics on the processs, too. Hope this helps!

[F1nut]

On the 40uf caps, I ordered (6) 20uf caps total and and 2 were wired in series to make a 40uf cap.

Kip, I hope you wired them in parallel and not in series.

[avguytx]

Kip, I hope you wired them in parallel and not in series.

I freakin' always get that backwards when I'm writing it out. My bad... Yep, they are in parallel.

[MillerLiteScott]

Thanks Texas AV Guy for all the info. I will put my wish list together and start saving.

Jesse,
What caps did you use in the 1C's you just re-built?
And is the RDO-194 the only option or is the RDO-198 an option?

Last night I dynamated all the driver baskets in my 1C's. I have my 2B's hooked up right now because of the dynamating. I actually got my wife to sit in the sweet spot last night and give a listen. She was blown away. Especially after she found out that it was only coming from the two front speakers. She kept asking me to put on another CD. REM Murmur is a great CD for SDA's, give it a listen.

Sorry for the minor thread jack.

Scott

[heiney9]

Thanks Texas AV Guy for all the info. I will put my wish list together and start saving.

Jesse,
What caps did you use in the 1C's you just re-built?
And is the RDO-194 the only option or is the RDO-198 an option?

Last night I dynamated all the driver baskets in my 1C's. I have my 2B's hooked up right now because of the dynamating. I actually got my wife to sit in the sweet spot last night and give a listen. She was blown away. Especially after she found out that it was only coming from the two front speakers. She kept asking me to put on another CD. REM Murmur is a great CD for SDA's, give it a listen.

Sorry for the minor thread jack.

Scott

Sorry to butt in, if you can swing it financially and are going to keep them use Sonic Caps. They are worth the extra cost also be sure to delete the 750pf silver mica cap on the stock 12uf cap(s). With a high quality cap the silver mica bypass cap in no longer necessary, IMO and many others.

If cost is a concern you could use Sonic Caps for the high portion and Solens for the low/mid portion and achieve excellent results. In both cases use Mills resistors. The 4.1TL option you did on your 2B's is not possible with the 1C's.

Once they are done and broken in they will sound phenominal. Completely transformed is the word I'd use. :)

Again sorry to butt in.

H9

[MillerLiteScott]

H9 I will more than likely go with the Sonicaps throughout again. And order a quad of RDO-194's. I may have wait a little while. Without checking the prices I am guessing it is @ $500.00 for the caps, resisters, and tweeters. I could thin the herd that currently occupies a bit of floor space in my basement, focus on one pair of speakers and stay of e-bay and craigs list.

[george daniel]

I'm betting that Jesse used Sonicaps,eliminated the silver mica(jumped),eliminated the poly's(jumped),rdo replacement tweets,,,and cardas binding posts.. Now,, with that said,,let's wait for the guru to arise,,,and we'll see how close,,or,,how far off I am. :) If the pair at PF are the ones that you are referring to,,I can tell you that I still can't get over the Stingray/1C setup,with either of the Cd sources,,simply stunning. :)

[MillerLiteScott]

George, I believe you are correct. I am just making sure. We shall wait till for the guru to arise and comment.

Scott

[MillerLiteScott]

Quick calculation of parts and pieces came up to @ $ 475.00 for 4 tweeters and new sonicap crossover components.

Scott

[george daniel]

Quick calculation of parts and pieces came up to @ $ 475.00 for 4 tweeters and new sonicap crossover components.

Scott

That sound about right,,have fun.:)

[hearingimpared]

I'm betting that Jesse used Sonicaps,eliminated the silver mica(jumped),eliminated the poly's(jumped),rdo replacement tweets,,,and cardas binding posts.. Now,, with that said,,let's wait for the guru to arise,,,and we'll see how close,,or,,how far off I am. :) If the pair at PF are the ones that you are referring to,,I can tell you that I still can't get over the Stingray/1C setup,with either of the Cd sources,,simply stunning. :)

I'll speak for the "guru;" all of the above! This is what he and I did.

One question I have for the guru is can the 4.1 upgrade be performed on the 1Cs?

[heiney9]

I'll speak for the "guru;" all of the above! This is what he and I did.

One question I have for the guru is can the 4.1 upgrade be performed on the 1Cs?

To the best of my knowledge I'm 99% sure it's a no ;). It may be possible if you comletely fab a new set of boards. But in the existing config on the stock x-over board no. The 4.1TL was going to be for the CRS's and the reason it works with the 2B's is because they have the same board and driver config. One reg. driver and one dimensional driver.

That's my non-guru understanding. :D Where the 'eff is Jesse or DK when you need them. :p

[F1nut]

Well, that's what I would have done to Ted's 1C's. However, those upgrades weren't practical from a monetary stand point. That set up at PF did sound damn good though, didn't it!?!

As for converting the tweeters, a quick look at the schematics shows that it would involve much more than just adding a cap, so it's probably best to stick with what you've got.

[danger boy]

why was the 4.1TL never accomplished? was the end of the SDA's so near for them to go ahead with the project and it was scratched all together?

[F1nut]

So Scott, has the mid-range improved?

[MillerLiteScott]

Jesse, I will have to say I got the bass to improve which seemed to balance out the sound beautifully. I made some wire management changes to my set up and placement changes to the speakers and it seems to be much better. I will give another listen. I also think my 2B's are a little nervous of the 1C's lurking in the other corner of the room.

I still want to talk to you about upgrades to my 1C's.

Scott