SDA SRS 2 Bi-amp Tube and Solid State advice
Lee Berger
Posts: 15
I just came into possession of a mint condition pair. Yesterday I decided to try bi-amping them using a Dynaco ST70 Series 3 (the 2016 version from Radial Engineering) for the mid-high, and a McIntosh MC2105 for the bass. The ST70 is 35 watts per channel and the McIntosh is 105 watts per channel. Both amps have level control so I set the ST70 at full and the MC2105 at around 50% which seems balanced. It sounds very good. My question is that the specs list the nominal impedance as 6 ohms. Would this still be 6 ohms in the bi-amp configuration? I am using the 8 ohm taps on both amps. Any suggestions and observations would be appreciated.
Other components:
Acurus Act 3 Preamp
Schiit Audio LOKI MINI+ Tone Control
Other components:
Acurus Act 3 Preamp
Schiit Audio LOKI MINI+ Tone Control
Best Answers
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The speaker's load (its impedance) doesn't change whether or not you use a single amplifier or two amplifiers. The speaker's internal crossover network isolates the two sections.
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Thanks. I thought so but wanted confirmation.
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Call Polk customer service, they will take good care of you. Mention you're a member here and it gets better.
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That's a Solen non polarized electrolytic.George / NJ
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Answers
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Sticker is incorrect, what you have there are SDA SRS 2.3, I also cannot remember so refresh my memory. I'm under the impression those were not a Blade/blade interconnect cable set. I thought they were late enough to actually be the Pin/blade interconnect.
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I thought so as the image search for the SRS2 shows a different model.
Image is prior to bi-amping. The original jumpers were missing.
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To be sure really need to see the socket or cable end.
I'm pretty sure all real Blade/blade models were outside the cup. Early pin/blade did actually use a B/b socket but were wired differently and inside the cabinet and socket was inside the cup.
I do feel yours are a P/b model.Post edited by pitdogg2 on -
Lee Berger wrote: »
I'm pretty sure that cute little subwoofer is useless now.Gustard X26 Pro DAC
Belles 21A Pre modded with Mundorf Supreme caps
B&K M200 Sonata monoblocks refreshed and upgraded
Polk SDA 1C's modded / 1000Va Dreadnaught
Wireworld Silver Eclipse IC's and speaker cables
Harman Kardon T65C w/Grado Gold. (Don't laugh. It sounds great!)
There is about a 5% genetic difference between apes and men …but that difference is the difference between throwing your own poo when you are annoyed …and Einstein, Shakespeare and Miss January. by Dr. Sardonicus -
Lee Berger wrote: »
I'm pretty sure that cute little subwoofer is useless now.
Ha! It’s actually part of the TV surround sound system. The Polks are for 2ch music. -
To be sure really need to see the socket or cable end.
I'm pretty sure all real Blade/blade models were outside the cup. Early pin/blade did actually use a B/b socket but were wired differently and inside the cabinet and socket was inside the cup.
I do feel yours are a P/b model.
The Polk SDA Handbook confirms your assumption:
The cabinet dimensions line up with this chart also from the Handbook
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Upgrade the crossovers and tweeters ( with Polk RD0-194's and you'll have a very nice set of speakers!Gustard X26 Pro DAC
Belles 21A Pre modded with Mundorf Supreme caps
B&K M200 Sonata monoblocks refreshed and upgraded
Polk SDA 1C's modded / 1000Va Dreadnaught
Wireworld Silver Eclipse IC's and speaker cables
Harman Kardon T65C w/Grado Gold. (Don't laugh. It sounds great!)
There is about a 5% genetic difference between apes and men …but that difference is the difference between throwing your own poo when you are annoyed …and Einstein, Shakespeare and Miss January. by Dr. Sardonicus -
Can you recommend a source for RD0-194’s? I recapped my RTA 12B’s recently. I’m not sure it improved anything. I used quality caps. I’ll visually inspect the 2.3 crossovers for leakage. That is when I figure out how to get to them🧐😁.Upgrade the crossovers and tweeters ( with Polk RD0-194's and you'll have a very nice set of speakers!
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Make sure you tell them you want RD zero 194.Gustard X26 Pro DAC
Belles 21A Pre modded with Mundorf Supreme caps
B&K M200 Sonata monoblocks refreshed and upgraded
Polk SDA 1C's modded / 1000Va Dreadnaught
Wireworld Silver Eclipse IC's and speaker cables
Harman Kardon T65C w/Grado Gold. (Don't laugh. It sounds great!)
There is about a 5% genetic difference between apes and men …but that difference is the difference between throwing your own poo when you are annoyed …and Einstein, Shakespeare and Miss January. by Dr. Sardonicus -
Lee Berger wrote: »
Can you recommend a source for RD0-194’s? I recapped my RTA 12B’s recently. I’m not sure it improved anything. I used quality caps. I’ll visually inspect the 2.3 crossovers for leakage. That is when I figure out how to get to them🧐😁.Upgrade the crossovers and tweeters ( with Polk RD0-194's and you'll have a very nice set of speakers!
What brand/model of caps did you use?
You won't see any leakage. Electrolytic caps have a useful lifespan of 10 to 20 years max. Yours are way past that.
Remove the PR to gain access to the crossover.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
Most caps don't leak electrolytes, they leak electrically.
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Most caps don't leak electrolytes, they leak electrically.
Ummm you never experienced Elna Dourex II caps. They were some of the most corrosive caps I've ever had experience with. Well after I recapped my Sony 33es CD player I was going back in to fix the traces they puked onto the copper traces and continued to eat away at long after they were gone. -
I know there are some caps that leak electrolytes, but they are usually defective from the start.
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I remember in the early 2000's there were surface mounted electrolytics that leaked in Sony and Panasonic professional video equipment (cameras and recorders) I was using at the time. A local tech was doing a pretty good business replacing those caps. He would photocopy the board and check them off as he did the replacements.
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Lee Berger wrote: »
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Bennic is the same as Dayton, both horrible. The electrolytic is a Solen. As a 27uF film cap is readily available there's no reason to use an electrolytic there.
Judging by the price of the Audiophiler caps I'll go out on a limb and say they are crap.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
Lee Berger wrote: »I remember in the early 2000's there were surface mounted electrolytics that leaked in Sony and Panasonic professional video equipment (cameras and recorders) I was using at the time. A local tech was doing a pretty good business replacing those caps. He would photocopy the board and check them off as he did the replacements.
Many of those were counterfeit nichicon and others coming out of China, yes it was bad. -
