Pairing my SDA CRS with NAD amp

Ronage

Hello everyone,

I am new to the Polk Audio products and this thriving community.

I recently discovered a pair of SDA CRS in my basement. What a wonderful serendipity!
I've been reading much about these little monsters in the past days and just paired them with my NAD AV-716. So far, they are delightful.

And of course, a newbie's thread cannot be completed without a question about the interconnect cable...

Does anybody know if the NAD AV-716 is common ground?
I've been searching much and couldn't find specific info about this matter online.

Also, any recommendation of a good source for the interconnect cables? I've seen 2 on eBay ($89.95 and $48.95, brand new by different sellers).

Your help is much appreciated.

-R

Dr_Wu

Welcome Ronage! You'll love the CRS when you've got them performing up to their capabilities.

I'd drop an email to NAD customer service about the common ground question. You definitely need the IC cable to get the stunning SDA effect. Blade/blade, I assume? Someone here might have an extra to sell.

You'll want to start thinking about update/upgrade. The SDA Handbook is invaluable. There are plenty of helpful members here who've been down this road (including me) who will gladly share their experience and advice.

Enjoy the ride!

TennMan

Welcome to the forum Ronage!. The crossover cable is something you could make yourself if you don't find one. Do a forum search and you should find instructions on how to make it. You need that cable to bring your CRS speakers to life.

Ronage

Dr_Wu & TennMan - thank you for your feedback. Will definitely email NAD and keep asking questions (and try to answer later on).

If you had asked me a just two weeks ago if I was going to write about vintage speakers in a similar forum, I'd probably think you were out of your mind...
However, the quick set-up of the DSA truly blew my mind. Before having the CRS, I was using the Bose 301 shelf (1984). The difference is huge. Especially with clarity and stamina. The DSA CRS seem to be clear, almost too clear, but this clarity hits on most frequencies. Still, I feel I'm still missing some bold low frequencies. I live in a large loft w high ceilings w some furniture/carpets. So the room doesn't echo or accentuate the lows too much.

My next step would probably be a new pair of the SDA A-1. I found a local pickup, an affordable price, and relatively good condition. This leads me to the next question:
Will you take a look at the photo below and tell me if the bubbles on the membrane could mean a problem with how well the speaker will function? The seller said that he purchased it this way (original owner) and it never caused any issues.

Thank you all!

Dr_Wu

I use a powered subwoofer with my SDA-CRS. The gain is turned very low, but adds just enough to augment the passive radiators.

Don't know where you live, Ronage, but if it's within a couple hours of Chicago, you might want to consider the beautiful 1c's that @Faustin is selling here.

Ronage

Brooklyn, NY!

And yeah - that set from @Faustin seems like a real monster. I think I'll start with the smaller version and see where it takes me

Any thoughts about that photo I shared?

Much appreciated, ya'll!

codycatalist

Those look like original SDA 2s. I don't believe the bubbling will have any effect on the sound, just the aesthetics.

When it comes to missing bass on the CRS, how do you have them placed? You should be anywhere from 5 to 8 inches from the back wall, no toe in, nothing obstructing the front plane of the baffle between the speakers. They should be about 6 to 8 feet apart and 2 feet minimum from side walls (some say 3 feet).

codycatalist

Also you will be losing bass without the interconnect cable.

boston1450

if i recall isnt there ways to check to see if amp is commom ground. Please chime in guys. I cant remember the process

boston1450

ronage did you mention which SDA CRS you have ? Blade-Blade or Pin-Blade. Mine are pin blade crs+'s. Just wondering. This may be helpfulhttps://www.manualslib.com/manual/362832/Polk-Audio-Sda-1c.html#product-SDA

boston1450

Those SDA 1A's or 2's or whatever they are may need amp & plenty of power. I think they may be a 4ohm speaker that dip LOW. Crs speakers are like SDA2b speakers and tend to be more flexible with power,,,, my SDA1c speakers i had i played around with receivers. Yamaha 120 wpc was ok. Marantz 52wpc at 10:30 on volume dial it started clipping. So i kept it hooked to Adcom555 or Parasound2250. Seemed to be much better with a amp. Even though SDA Manual says 50wpc they need ump. Love playing with gear on rainy day

mlistens03

boston1450 wrote: »

if i recall isnt there ways to check to see if amp is commom ground. Please chime in guys. I cant remember the process

Multi meter set to resistance between the ground terminals.

Ronage

Great tip, codycatalist. Def a lot of work to be done.

It's like tuning musical instruments... it takes time and skill.

Is there a photo/drawing from Polk's manual that shows the optimal way to position the speakers, including angles (SDA CRS)? Also, what about the height, considering the fact that my ceiling is apx 14-15' tall (currently placed 6-7' tall).

Thank you for your time!

Faustin

Welcome Ronage to Club Polk. You said you discovered the SDA CRS's in your basement. If it were me, I would continue to "explore" your basement to see what else is down there. Maybe a Marantz 8b amp or ??

boston1450

Yes Ronage i posted manual above. Thanx Micah

boston1450

That manual is for crs speakers also. Placement is listed. Look at you IC cord plug on rear of speaker. Pin Blade or Blade Blade slots. Does your speaker have 1 tweeter or 2 ? (Crs+ is pin blade single tweeter)

boston1450

mlistens03 wrote: »

boston1450 wrote: »

if i recall isnt there ways to check to see if amp is commom ground. Please chime in guys. I cant remember the process

Multi meter set to resistance between the ground terminals.

Can those negative terminals be strap'd to make it common ground also

boston1450

I tried to dig n find info on the NAD you have. Nice AV receiver. Ive heard that most all receivers are common ground. But NAD is a tad different in my mind. So i didnt find anything. Worth a talk with NAD to be certain. Came up short elsewhere. Ut found thishttps://forum.polkaudio.com/discussion/46332/common-ground-amps . there is more out there but not sure it will be with that model AV receiver

codycatalist

Ronage wrote: »

Great tip, codycatalist. Def a lot of work to be done.

It's like tuning musical instruments... it takes time and skill.

Is there a photo/drawing from Polk's manual that shows the optimal way to position the speakers, including angles (SDA CRS)? Also, what about the height, considering the fact that my ceiling is apx 14-15' tall (currently placed 6-7' tall).

Thank you for your time!

The CRS came with a stand, don't know the dimensions but tweeter ear level is usually a good rule of thumb.

mlistens03

boston1450 wrote: »

mlistens03 wrote: »

boston1450 wrote: »

if i recall isnt there ways to check to see if amp is commom ground. Please chime in guys. I cant remember the process

Multi meter set to resistance between the ground terminals.

Can those negative terminals be strap'd to make it common ground also

That depends on the receiver/amplifier. Some can, some can't, just gotta ask the manufacturer.

Ronage

@Faustin - had to google the 8b, WOWZA! What a sexy monster. I still have my old Marantz (2238 I believe), but it is at my parents' house, on the other side of the ocean.
As a teen, I used to DJ at parties with this Marantz, taking 15" Eminence speakers like it was a walk in the park. Good ol' 90's!

@boston1450 - thank you for your helpful tips and link to the manual. I must have missed your post before submitting mine. Yes, my SDA has 2 tweeters with a blade/blade IC cord (strangely, only 1 tweeter works - not sure if it is because I haven't used the IC cord yet).

@codycatalist & @mlistens03 - thank you both.

Much work to be done this weekend!

Also, it seems like I am getting my new set of SDA 2A on Monday. Seller sent a vid and going to check it out myself!

I think I am getting old. Or maybe not?

RandyCroissant

Welcome to the forum Ronage, my understanding is the 2 tweeter CRS utilizes one tweeter for stereo and one for SDA which means without the I.C it will not work. Also to add many owners of that particular CRS like the sound better with that tweeter disconnected lobing I believe is the issue.

Ronage

Thanks, @RandyCroissant - will def test A/B and figure out the most delightful sound. At the end of the day, it's clarity that I am aiming/looking for. So far, one tweeter seems to be more than enough (flow of highs in the room) but will make a better judgment as soon as I test the SDA in action. Gotta make sure my NAD is common ground first!

I know I have a long way, but I am off to a good start!

Thank you all~