sda-1 speakers

millerdog

Hello all!
I did a search on these speakers that I have recently acquired. I still have some questions.

Are they 4 or 6 ohm loads? Do I really need the cross talk connector?
I know these puppies need power, but they sure sound good powered by my Fisher X100C which only has 25wpc. Am I under driving them? What is the sensitivity rating on these?
The silicone things on the tweeters seem to be cracking, but I don't hear any distortion. Is that a problem?
Lastly, how do I tell what actual model I have.
The two tweeters are mounted vertically on top, followed by the four mids? and then the woofer.
thanks! I really am getting into these speakers!

mhw58

Originally posted by millerdog
Hello all!
I did a search on these speakers that I have recently acquired. I still have some questions.

Are they 4 or 6 ohm loads? Do I really need the cross talk connector?
I know these puppies need power, but they sure sound good powered by my Fisher X100C which only has 25wpc. Am I under driving them? What is the sensitivity rating on these?
The silicone things on the tweeters seem to be cracking, but I don't hear any distortion. Is that a problem?
Lastly, how do I tell what actual model I have.
The two tweeters are mounted vertically on top, followed by the four mids? and then the woofer.
thanks! I really am getting into these speakers!

The SDA1C's are listed as 6 ohms by Polk, effeciency is 92 dbs. Yes you need to get the SDA connector, without it you are missing out on the SDA effect which is incredible. You may have a problem getting a connector for your speakers because Polk no longer makes the pin/blade connector used by the 1C's.
Yes you need a more powerful amp. I'm running my 1C's with
an Onkyo receiver that is rated at 105 wpc at 6 ohms and
everyone tells me I need more power. Most people on this
site feel you need 200 wpc to really make your speakers
sing. I'm happy with my Onkyo but will upgrade someday.
As to what model you have, it sounds like you have the
1C's which are the best. The earlier 1 models had the tweeters
side by side horizontally, the 1C's put them vertical one on
top of the other. I'm not at home now but I think it lists
the model on the back, I think my speakers say 'SDA1-C'
on them. They are great speakers and I love them. Welcome
to the SDA world.
Mike:D

F1nut

Hey Mike, good to see you posting.

I'll add to your excellent post by telling millerdog that the "woofer" is really a passive radiator and to enjoy the full benefit of SDA's you will need the interconnect cable. This link will show you what it looks like and maybe Har will sell you one, if you ask him nicely.
http://clubpolk.polkaudio.com/forum/showthread.php?s=&threadid=9030
You should plan on upgrading the power you have and be sure it's of the high current type and is a common ground type. FYI, some folks seem to be having problems with Yammies not being a common ground type. When you say the silicone things, do you mean the outer dome on the tweeter?
One last thing, welcome to the forum.

F1

mhw58

F1,
Good to hear from you too. I just spent the weekend cranking
the new Zeppelin dvd's on my SDA's. Fantastic!!!!

Millerdog,
Go to this link:
http://groups.yahoo.com/group/mikespolkpage2/
and click on the photos link, then find the SDA envelope.
Click on it and you will find pictures of all the SDA's. It's
possible you have the 1B's, they also mounted the tweeters
vertical. The 1B's have several inches of wood at the bottom
where the 1C's only have about a 1 inch wood base.
When you figure out what model you have, you can order
an owners manual from Polk and they will send it to you
for free. Polk's customer service is the best.
Mike

millerdog

Thanks Mike and F1,
Will check out those links. The speakers say SDA-1 on the back, and they have that one inch foot on the bottoms.
I guess I need to find a bigger amp now.:)

mhw58

I looked at my speakers and they say
SDA 1 on them and they are 1C's so it
sounds like you have 1C's also. They are
the best of the 1 series. F1 gave you some good advice about contacting Har
about getting the interconnect cable.
It is a must. Once you get the cable and
a bigger amp, you'll be in heaven.
Mike

millerdog

thanks for the info Mike.
My old man says he got the cable someplace, so I guess I gotta go over and sift through his stuff! He just moved so it's a real mess:(
Again, thanks for the info! Will post back when I find that cable:)

mhw58

Millerdog,
Did your old man buy the Polk SDA's new? You're very lucky
to acquire such excellent and unique speakers. What kind of
an amp did your dad power the 1C's with? If you're looking
for a 2 channel amp, you can get one very cheap these days.
Lots of people are selling their stereo amps to buy a
home theatre receiver. Ebay is loaded with good stereo
amps with 100 wpc that will be a big upgrade for you.
A new amp and the connector cable will let you in on the
SDA experience and you'll be one happy camper.
Mike

millerdog

Mike,
I am sure my Dad got these used. I believe he was using a Sansui AU919 to power them up. I asked him why he didn't want em and he mumbles something about "not enough power." Didn't know what the hell he was talking about until I did the research on these puppies:rolleyes:
Since these present a second system for me, I don't quite know which direction I am going with them. I currently run LothX bookshelve speakers and Bottlehead Paramours, so these speakers are leading me in a totally different direction.
I would like to try and monoblock them, but for now your suggestion seems more in my budget:)
One more question: Did the 1Cs have that transformer thing in the cable? That would help me as I wade through all my Dad's uh....stuff.
thanks

F1nut

millerdog,

According to my info, 1C's with a left channel # greater than 5975 and right channel # greater than 6001 can use and probably came with both the AI-1 (transformer) cable and the standard cable. It's hard to miss either cable....standard is black and 20 feet long with little plug heads on both ends. The AI-1 is the same with a big black box in the middle of the run.

millerdog

Thanks for the great info guys!
One more question, what was the power rating of the 1Cs?
I have read anywhere between 1000 and 500w.

F1nut

Between 50 - 500 wpc.

millerdog

thanks F1!
Damn! you guys are good!:D

mhw58

Millerdog,
F1 is a genius when it comes to SDA's. He helped me a lot
when I first got my SDA's. He can help you a lot with the setup.
SDA's will sound best if you put them about 6 to 8 feet apart.
You have to put them the same space from the wall and you
face them forward, you don't toe them in. Also make sure you
have at least 3 feet open space to the nearest side wall.
You don't put them in the corner as this will decrease the
SDA effect. This is all explained in the owners manual.
Any other questions, fire away.
Mike

Tour2ma

md,
Per your request I'll post over here. Below is where F1 told you of the two SDA IC's...

Originally posted by F1nut
According to my info, 1C's with a left channel # greater than 5975 and right channel # greater than 6001 can use and probably came with both the AI-1 (transformer) cable and the standard cable. It's hard to miss either cable....standard is black and 20 feet long with little plug heads on both ends. The AI-1 is the same with a big black box in the middle of the run.

Not sure what you meant by "virtual common ground" in your last post over in the tube amp thread.

Let's pick it up from here.

millerdog

I think F1 was the first to mention the "common ground" thing to me. I have no idea what that means. From what I understand, some circuits are built on ground rails (virtual ground)? but they aren't true grounds?
help me out here!

thanks tour for moving the post! I am a mod on another forum and hate hijacking:rolleyes:

These speakers seem to be very uh...component sensitive?

Tour2ma

Not really all that sensitive. The vast majority of amps are common ground design so the standard IC can be used. A couple members here have had problems with a particular Yamaha model. The old Carver M500t was not common ground, but the other Carvers M's were... not sure about the earlier Carvers.

Common ground is as simple as it sounds. Internally the two negative, i.e., ground, speaker terminals are wired together. In some amp designs, however, they are not.

The SDA cable effectively creates a short across the channels that a non-common ground amp can't tolerate, which leads to bad things (sorry for getting so technical here).

In another thread kelley said his amp manf. told him to just add an external jumper between his negative posts. Said he has run that way for years with no problems. Look near the bottom here:
http://clubpolk.polkaudio.com/forum/showthread.php?s=&threadid=9981&highlight=ground

So have you rumaged through your Dad's attic yet for the IC's?

DarqueKnight

Originally posted by millerdog
These speakers seem to be very uh...component sensitive?

I have found my SDAs to be particularly sensitive to the kind of power amps used with them. They tend to prefer high power/high current designs.

DarqueKnight

Originally posted by mhw58
It's possible you have the 1B's, they also mounted the tweeters vertical. The 1B's have several inches of wood at the bottom where the 1C's only have about a 1 inch wood base.
When you figure out what model you have, you can order
an owners manual from Polk and they will send it to you
for free. Polk's customer service is the best.
Mike

Some of the earlier all black "studio" versions of the SDA 1C had cabinets with the 3 inch wooden pedastal similar to the SDA 1B.

One way to tell for sure what you have is to look at the SDA interconnect cable and jacks: the 1B used a blade/blade connector. The 1C used a pin/blade connector.

Tour2ma

Originally posted by raife1
I have found my SDAs to be particularly sensitive to the kind of power amps used with them. They tend to prefer high power/high current designs.

Sounds more like a definition of "rugged" to me...

millerdog

I went to my old man's house yesterday and was overwhelmed by the amount of crap he has:( I think I'm just going to try and make my own cable.
I did separate the speakers by about seven feet, but feel they need even more. I think I can get eight feet without getting to close to the walls.
Since today was a holiday, I spent most of the afternoon listen to these puppies and was really impressed. Norah Jones and Dave Brubeck never sounded so good!
Damn! Now I gotta get another TT:D
Oh, by the way, I rolled in an old Sansui receiver I had that is rated at about 45wpc and I liked it! To get good SPL I only had to hit about eight o clock on the volume. That was using the eight ohm taps and zip wire. Sounded much more detailed than my H/K and Kimber cables.

Tour2ma

And so the journey begins... fare thee well...

They'll play with 45 wpc, especially on the material to which you were listening. Music choice is a factor we often overlook. Acoustic jazz is a good example of less demanding material from a power standpoint, but not a speaker standpoint as you discovered.

Sounds like you need to meet polkatese... Which Brubeck?

Rock... more power; Full orchestra.... most power.

But meanwhile it sounds as if you have a few amp, speaker wire combo's to explore.

As for that TT... How about an AR XA?

millerdog

Tour,
You are getting way ahead of me on this....
Next for me is a MusicHall MMF5. That replaces my current Dual 1246. I am very poor!
For these speakers, I was thinking a Jolida 1501 intergrated. But that's wayyyyyy down the line. Once you get into glass there aint' no going back!:) I need to test my Fisher against the Sansui now.
Oh, it was Dave Brubeck's "Time Out" of course!
Now days, I hardly listen to real hard rock. The last LP I bought was Rickie Lee Jones if that's any precedent. I am listening to RLJ "Pirates" now on my bedroom system.

Tour2ma

Sorry, not trying to push, but you've got some interesting combo's. See you're already looking to hitch up the Fischer.

You will love "Chuck E's in Love" on the SDA's. The guitar and snaps jump right out at you.

Do remember that you are listening to about half your speakers right now. The IC adds the other half, opens new doors image-wise and may just have you moving them closer together again. And sooner or later you'll have to borrow some Pink Floyd... it's a law I think... at least in the lower 48...

"Time Out" a classic. Love Paul Desmond's alto. If you have the chance to listen to a pair of Magnepan 1.6's, take Time Out with you and be prepared to be slack jawed.

On the AR... I'm reconditioning some XA's I've nabbed on ebay over the past few months. Couple folks here are in line to get one. Very sweet, classic TT. Also playing with solid wood bases, some different arms, etc. for the more adventuresome.

millerdog

Tour,
You sound like you should come and check out audiokarma.org
It's a site I help moderate. We're all a bunch of cheap **** that look for good deals on old stuff:)
Those audio research TTs you got may be a bit more than what AK members are used to seeing;) We got a handfull of members that do have SOTAs, Oracles, Rega, Thorens etc.
And we got a nice DIY forum. Am I poaching members here? sorry!
On those cables....I bought some radshak zip wire and spades to see what will happen. Oh and I got DSOTM:D

millerdog

Okay! I used some 18g zip wire to hook the speakers together. A friend noticed an immediate improvement in the soundstage.
He was sitting in the sweet spot while I fiddled around so I really didn't get to hear what he was hearing.
After he left, I put on some music and noticed a more focused soundstage. Earlier, sometimes the music would get left or right channel heavy; now it seems locked front and center.
To my ears, the soundstage is also a bit wider.
To get the full SDA effect, should I try to move them in closer together?
What have you guys done to get the right imaging?
thanks!

F1nut

To get the most out of your speakers they should be at least 3 feet from any side wall and facing straight ahead, no toe in. The distance from the back wall can vary, the closer they are the more bass you get. Try anywhere between 5 inches to 18 inches. Try spacing them 6 feet apart (inside edge to inside edge) and go out from there if room permits, but I have found 6 feet is the minimum. The sweet spot is roughly equal to the distance apart. If you contact Polk and ask nicely, they will send you a manual for your speakers which explains set up, etc.

Enjoy

Tour2ma

F1 speaks the truth... I've found about 8' to be the max. I liked 6' better, but big ol' magnets were chewing into my picture tube, so had to split them a bit more. They're 7' right now.

It is worth the trouble to get the fronts of the two speakers as near to in the same plane as possible. This means leveling them and aligning them. Level them first, then a piece of string stretched across their top, front edges works for the alignment.

If you're on thick carpet and/or carpet pad, spikes are available through Polk CS. Will help not only the leveling, but will also couple them to the underlieing floor eliminating any tendancy for the speaker to move.

When the SDA is in full bloom you'll hear music coming from places the speakers aren't... way out to the sides and sometimes you'll swear it's even coming from down the hallway...

F1nut

Tour speaks the truth too....:D

The spikes will also help solidify the bass.

millerdog

thanks guys for all your help!:)
I am still playing around with speaker placement, but am very impressed with the sound.:D
thanks again for your recommendations.
Jeff