SDA-1c or original SRS-2 for 2ch stereo??

Malcolm G

How does the Sound Quality of the original SRS-2 compare to SDA-1c?

This is for music (2ch stereo; no HT) in a large room. I want the best SQ, not concerned about volume levels.

ben62670

The SRS-2 if it is pin blade.

gdb

I asked the same question a couple of years ago and was told the larger passive radiator in the SRS2s made them a slightly more desirable choice. the SRS2s are also a lot rarer it seems. I was very lucky to get a great price on a pair of pin/blade SRS2s from a member here and was very happy to make a day-long trip through Virginia to get them! Never heard any 1Cs, but as long as I have The SRS2s....I don't think I need to try the 1Cs. Now SRS2.3TLs, thats another story. I'd love to find some of them for a comparison!:)

billbillw

They would both be very good choices and it would be hard to go wrong with either. However, for best sound quality, you should plan on upgrading the tweeters and rebuilding the crossovers.

When Ben said that Pin-Blade SRS-2 is preferable, I think its because the Pin-Blade SRS uses a crossover that is much cheaper to rebuild than the blade-blade version (due to the number and size of capacitors that need to be replaced).

I have a set of SDA-1C and I'm very happy with them.

heiney9

Either would be great. The SRS2's are a bit more difficullt load to drive and if you ever want to use a non-common ground amp or mono blocks you can't with the SRS2's but you can with the 1C's.

IMHO, the 1C's are the gem of the entire line. They are the most popular, easier to drive and can be set-up in medium to large room. Are easier and less costly to modify.

That all being said, go with the ones that are closest to you and/or are in the best shape as you won;t go wrong with either one of them.

H9

ben62670

The SRS-2's are just as easy to drive if They are pin blade. It uses the same XO as the 1C's.

gdb

Why wouldn't the pin/blade SRS2s be able to use the A1-A cable and non-common ground or mono-block amps ? Mine have dual sets of binding posts so I presume that they can be bi-amped at least.

ben62670

The Pin Blade SRS-2's can use the A-1

gdb

Thanks Ben, I had a hunch that they could.:)

bluecomet

I have both the SRS 2 pin/blade version and the SDA 1C's. The SRS 2's are basically SDA 1C's on steroids. If you like the sound of the SDA 1C's, then you basically get more of what you like with the SRS 2's. It has a bigger base sound and wider soundstage but the sound is very close sonically to the 1C's. The replacement RDO's made a huge difference with my SRS 2's. It could be that the SRS 2 tweeters the SL2000's degraded more than the ones in my SDA 1C's. Either way you can't lose on whichever you choose. The SRS 2's are 6 ohm speakers so you can run them on newer AVR's if you wanted to and incorporate them in a HT system. I use to own the original SRS 2's and they were 4 ohm speakers and were harder to drive. The mid range was not as good as the pin/blade version. I believe the pin/blade version uses different drivers. I don't see myself selling either of my SRS 2's or SDA 1C's. They are both keepers. Heiney9 is right. Locate either set of speakers in the best shape you can find and you will be pleased.

Larry Chanin

heiney9 wrote: »

The SRS2's are a bit more difficullt load to drive and if you ever want to use a non-common ground amp or mono blocks you can't with the SRS2's but you can with the 1C's.

Hi,

Could you please elaborate? Do you mean that some of the 1C's can be used with the A1 interconnect? I have a 1C with a blade-blade connection so am I correct they are not suitable for use with the A1 interconnect and therefore can't be used with mono blocks?

Thanks.

Larry

ben62670

Are you sure they aren't 1B's?

heiney9

Larry Chanin wrote: »

Hi,

Could you please elaborate? Do you mean that some of the 1C's can be used with the A1 interconnect? I have a 1C with a blade-blade connection so am I correct they are not suitable for use with the A1 interconnect and therefore can't be used with mono blocks?

Thanks.

Larry

Early 1C's can't be used without calling Polk for a work around to use the AI-1. I'm running out the door but I promised another member the serial number for the L & R 1C's that can use an AI-1 w/o furthur modification. When I get back I'll post them here.

H9

Larry Chanin

ben62670 wrote: »

Are you sure they aren't 1B's?

Hi Ben,

Yes, pretty sure they are 1C's. I'm the original owner.



Larry

ben62670

There were a few transitional models that had the Blade Blade connector.

Malcolm G

Did the original SRS-2's come in both blade-blade and pin-blade configurations?

If the crossovers are different I'd imagine the sound is somehow different, and it sounds as though the blade-blade is inferior?

If the crossovers in the sda-1c and pin/blade srs-2 are identical, are the drivers also identical; the only differences being cabinet size and PR size?

Malcolm G

Has anyone taken the guts of an sda-1c, bought 15" PRs and do a diy larger cabinet??

Larry Chanin

ben62670 wrote: »

There were a few transitional models that had the Blade Blade connector.

Hi Ben,

Yes, I also have a pair of SDA-CRS+ that also have blade-blade connections.

Larry

heiney9

The AI-1 interface can be used only with serial numbers greater than the following

1C's Left channel #5975 or greater; Right channel #6001 or greater
Some early units of SDA 1C and all units of 2B require plug adapters and some internal modifications to the x-over

The affected 1C's are Right channel #6001 thru 6310 & #6501 thru 6678
Left channel #5975 thru 6370 & #6532 thru 6656

So any any serial number less than stated in the 1st paragraph can NOT use the AI-1 and those serial numbers listed in the 2nd paragraph can use the AI-1 but need an plug adapter and internal x-over mods. I am assuming because of the blade/blade IC.

This info comes straight from the SDA Compendium 2nd ed. If you have questions it's best to call Polk customer service.

Hope this helps

H9

RuSsMaN

Signature Reference Series, period.

My favorite SDA, the SRS 2.

comfortablycurt

Malcolm G wrote: »

Has anyone taken the guts of an sda-1c, bought 15" PRs and do a diy larger cabinet??

That's an interesting idea...Do the 1C's and SRS 2's use the same MW's? What about the XO's? Same or different?

heiney9 wrote: »

Early 1C's can't be used without calling Polk for a work around to use the AI-1. I'm running out the door but I promised another member the serial number for the L & R 1C's that can use an AI-1 w/o furthur modification. When I get back I'll post them here.

H9

heiney9 wrote: »

The AI-1 interface can be used only with serial numbers greater than the following

1C's Left channel #5975 or greater; Right channel #6001 or greater
Some early units of SDA 1C and all units of 2B require plug adapters and some internal modifications to the x-over

The affected 1C's are Right channel #6001 thru 6310 & #6501 thru 6678
Left channel #5975 thru 6370 & #6532 thru 6656

So any any serial number less than stated in the 1st paragraph can NOT use the AI-1 and those serial numbers listed in the 2nd paragraph can use the AI-1 but need an plug adapter and internal x-over mods. I am assuming because of the blade/blade IC.

This info comes straight from the SDA Compendium 2nd ed. If you have questions it's best to call Polk customer service.

Hope this helps

H9

Great information Brock! This thread has made me a think of a potential snag to some of my plans...

I've been planning on upgrading my 2A's to TL status, since it was determined that it was possible in this thread.

I've been thinking about guinea pigging my 2A's for this experiment...but now I'm rethinking that. The 2A's are blade/blade, so they can't use the AI-1 IC. As far as I know, there isn't any way to use mono blocks with them...which could be a problem in the future. There are at least a few different mono blocks that I'd like to try eventually down the line...and with the 2A's, that wouldn't be a possibility.

So, I think this brings me back to wanting a pair of 1C's...the indecisiveness strikes again!! Some LSi9's or LSi15's will be coming along before I take my next step down SDA Avenue though. I think 1C's are still a couple years off for me.

When I'm ready to upgrade to 1C's, I'm definitely going to try and track down a pair of 1C's that can use the AI-1 without requiring modifications. These are the ones that had a two piece crossover, correct?

Just to be clear...

Left channel 1C's with a serial number between 6370 and 6532, or greater than 6656, do not require modification to use the AI-1.

and...

Right channel 1C's with a serial number between 6310 and 6501, or greater then 6678, do not require modification to use the AI-1.


Did I get that right, or did I read it completely wrong?...lol

heiney9

Malcolm G wrote: »

Has anyone taken the guts of an sda-1c, bought 15" PRs and do a diy larger cabinet??

Why make Franken-Polks? There is more than just a cabinet to SDA's.

The 1987 version of the SRS2's uses the same drivers as the 1C's. But, I believe the x-overs are different. What you suggest is way more work and the difference wouldn't be worth the effort.

Either find 1987 SRS2's or be happy with 1C's.

IMO

H9

inspiredsports

I remember auditioning both the SDA-2B and SDA-1C numerous (probably 10) times at my local Audio Craft store back in 1987 before deciding on the 2B's. I felt the sound was very similar and went with the smaller, more affordable 2B.

In 2008 I "TL'd" the 2B's, bought a pair of 1986 SDA SRS 2's, and then also found a way to "TL" the SDA SRS 2's as I could not "go back" to less revealing SL2000/RDO-194 sound after hearing the RDO-198's in the TL'd 2B's.

It's coincidental that just this morning I was A/B-ing the two sets. The SDA SRS 2 has a vastly wider sound-stage and subtly fills the room with bass in a way the 12" passive simply can't adequately compete.

The 4 ohm 1986 SDA SRS 2 is harder to drive than the higher impedance 1987 model, and the low pass cap values are large, but the sound quality is stellar. As a side note, if your amp is stable driving into a 4 ohm load, there is the benefit of the added wattage potential at the speakers. It is true that being blade/blade, you can't use the AI-1 to accommodate non-common ground amps.

I'm not sure what drove Polk from using four 4 ohm MW6509's per cabinet in 1986 to the 2 each 8 ohm MW6511/MW6510 configuration of 1987, but I'm guessing it might have been a cost consideration.

Toolfan66

H9

Isn't the difference in using the A1 interface in the 1C's dependent on whether you have the 2 piece crossover or the 1 piece crossover the same as what serial numbers you can only use??

I have the 1 piece crossover, and I will check my serial numbers when I get home..

Can someone post a pic of a SRS-2? i know what a 2B looks like and I get the other 2's mixed up sometimes..LOL

heiney9

TOOLFORLIFEFAN wrote: »

H9

Isn't the difference in using the A1 interface in the 1C's dependent on whether you have the 2 piece crossover or the 1 piece crossover the same as what serial numbers you can only use??

I have the 1 piece crossover, and I will check my serial numbers when I get home..

What I wrote in the above post comes directly from Raife (Darqueknight) as it was printed in the Compendium Ed. 2. I'm sure his info comes directly from Polk and that's all I can say.

If anyone has questions beyond that, I'd recommend they contact Polk customer service. If your serial numbers are beyond the ones listed you should be fine. One could loosely deduce that info about 1 vs. 2 board x-over but I have no idea if there is any correlation. It make sense, but I can't state that as a fact.

H9

inspiredsports

TOOLFORLIFEFAN wrote: »

. . . can someone post a pic of a SRS-2? I know what a 2B looks like and I get the other 2's mixed up sometimes. . .

Here are a couple of quick snapshots of the 1986 blade/blade SDA SRS 2. 1987's look the same, but have different crossovers and MW's.

142 lbs each, 50" high X 20-11/16" wide X 12-11/32" deep.
.

Backtothe80s

inspiredsports wrote: »

The 4 ohm 1986 SDA SRS 2 is harder to drive than the higher impedance 1987 model, and the low pass cap values are large, but the sound quality is stellar. As a side note, if your amp is stable driving into a 4 ohm load, there is the benefit of the added wattage potential at the speakers. It is true that being blade/blade, you can't use the AI-1 to accommodate non-common ground amps.

I'm not sure what drove Polk from using four 4 ohm MW6509's per cabinet in 1986 to the 2 each 8 ohm MW6511/MW6510 configuration of 1987, but I'm guessing it might have been a cost consideration.

I have 2 pairs of the blade/blade SRS 2s, and am running one set with a Carver TFM-55x (at between 500-600 watts/channel into 4 ohms), and the other with an Adcom GFA-555 (at about 325 w/c into 4 ohms). The added power of the Carver definitely makes a difference, particularly with bass at higher volumes.

While I have upgraded both sets with RD0194 tweeters, both have the dual X/O set up, and I haven't done anything to the crossovers yet except to replace the polyswitches. This thread serves as a reminder that I need to, at the very least, do the X/O upgrades to replace all caps and resistors.

If I want to go to a full TL upgrade, will it be worth my time and money? It would require all new MW's, wouldn't it?

stubby

Backtothe80s wrote: »

I have 2 pairs of the blade/blade SRS 2s, and am running one set with a Carver TFM-55x (at between 500-600 watts/channel into 4 ohms), and the other with an Adcom GFA-555 (at about 325 w/c into 4 ohms). The added power of the Carver definitely makes a difference, particularly with bass at higher volumes.

While I have upgraded both sets with RD0194 tweeters, both have the dual X/O set up, and I haven't done anything to the crossovers yet except to replace the polyswitches. This thread serves as a reminder that I need to, at the very least, do the X/O upgrades to replace all caps and resistors.

If I want to go to a full TL upgrade, will it be worth my time and money? It would require all new MW's, wouldn't it?

I am gathering parts for the TL upgrade myself. No, you don't have to replace your midwoofers. Just your tweeters with RDO198's. (and the associated x-over parts!) I firmly believe it will be worth the T&M. I think TL model speakers sound much better than earlier efforts.

stubby

Malcolm G

heiney9 wrote: »

Why make Franken-Polks? There is more than just a cabinet to SDA's.

The 1987 version of the SRS2's uses the same drivers as the 1C's. But, I believe the x-overs are different. What you suggest is way more work and the difference wouldn't be worth the effort.

Either find 1987 SRS2's or be happy with 1C's.

IMO

H9

Ben said the crossovers were the same as the sda-1c. I was thinking that after people replace the caps and resistors in their x-overs, rewire with silver cable and special Cardas spade connectors, upgrade the tweeters, replace a locked driver or two, pad down the driver frames with Dynamat, seal everything up with rope caulk, make new cloth sides and wood caps and balance everything on gel discs for better bass... the only thing I haven't seen anyone mess with is a better cabinet. So if I never found an SRS-2, I figure I could eventually make one out of a sda-1c... Those cabs don't look all that complicated (though i haven't seen the internal bracing).

All that said, yes I'd rather buy one.

Sounds like either the SDA-1c or SRS-2 would be fantastic choices.

inspiredsports

Backtothe80s wrote: »

I have 2 pairs of the blade/blade SRS 2s, and am running one set with a Carver TFM-55x (at between 500-600 watts/channel into 4 ohms), and the other with an Adcom GFA-555 (at about 325 w/c into 4 ohms). The added power of the Carver definitely makes a difference, particularly with bass at higher volumes.

While I have upgraded both sets with RD0194 tweeters, both have the dual X/O set up, and I haven't done anything to the crossovers yet except to replace the polyswitches. This thread serves as a reminder that I need to, at the very least, do the X/O upgrades to replace all caps and resistors.

If I want to go to a full TL upgrade, will it be worth my time and money? It would require all new MW's, wouldn't it?

Hi Bruce, I've answered your PM and will help any way I can. Absolutely worth it in my humble opinion.

It can be done with just the top 2 tweets being replaced with RDO-198's and 2 5.8uf Sonicaps bypassing a 2.7ohm resistor in the high pass half of the 2 piece crossover if budget is a concern. MW's stay the same.

A full crossover rebuild with Sonicaps (or better) and replacing all 4 tweets yields stellar results.

NOTE: I have the 1986 4 ohm blade/blade 2 piece crossover SDA SRS 2's with 4 MW 6509's per cabinet. A method to TL the 8 ohm 1987 pin/blade 1 piece crossover SDA SRS 2 with MW6511's/MW6510's has not been conquered yet. If someone does figure out the 1987 mod, I think it will also translate to the SDA 1C, but at this point we are only talking 1986 blade/blade SDA SRS 2.

gdb

"NOTE: I have the 1986 4 ohm blade/blade 2 piece crossover SDA SRS 2's with 4 MW 6509's per cabinet. A method to TL the 8 ohm 1987 pin/blade 1 piece crossover SDA SRS 2 with MW6511's/MW6510's has not been conquered yet. If someone does figure out the 1987 mod, I think it will also translate to the SDA 1C, but at this point we are only talking 1986 blade/blade SDA SRS 2."




I hope that a method for "TL'ing" the pin/blade models can be worked out someday!:(