The Tale Of My New (2me) SDA 2s

memetic007

My first decent stereo rig which I had from 1978 to 2002 was Polk 5 speaker based. Various electronics over the years. The 5s won in a 1978 shoot-out over the Large Advents. For years we didn't have a TV so the system got very regular use. Perhaps the Polk sound got engraved in my brain.

The Polk-based system survived 4 moves, but in 2002 one of the drivers ruptured and such an old system didn't seem worth fixing in those days. We soon moved again to a house with a decent but "casual listening" whole house system. And the same in our next house 10 years later.

After 22 years of "casual listening" whole house systems, "computer speakers," boom boxes and such, in February 2024, when my new outbuilding home office was construction-complete, I decided to create a decent sound system. After too much (of course) online research I chose a safe-and-sane system of a Yamaha A-S801 integrated amp and a set of Klipsch Premiere RP-600M IIs. Sound sourced online. Initially Amazon, then Amazon HD, then Qobuz.

Nice! Certainly far better than the various desktop computer speakers I'd had in my offices over the years and better by a lot than any of our whole house systems.

I could have easily been satisfied with the results.

But noooooo.... the mind virus of audio curiosity almost immediately arose!

I became curious how the new Klipsch speakers compared to my old beloved Polk 5s. I was mildly surprised (probably shouldn't have been) that there was a lively market in old audio gear. I quickly found I could buy a "recently serviced with silver coil dome tweeter" Polk 5 on ebay. I didn't have a clue what they meant by the tweeter remark but silver sounded good! I now know those were SL2000s and many people prefer the older "peerless". Oh well. Anyway, they were only $180 plus shipping on ebay so I ordered them.

I did a lot of a/b testing and concluded that the RP-600M IIs were more precise and sounded better for classical; but I liked the more open sound of the Polk 5s for classic rock, outlaw country, etc. It's probably a wash on vocal-heavy neo-folk and for jazz.

Back in the day, the Polk 5s bass was quick but a bit weak. So it was with these. Initially, I spun up a Roon equalizer that boosted the Polk's bass - a straight descending line from +10db at 20hz to neutral at 400hz. That moved the Polks further ahead on classic rock and country. Being lazy, rather than switching the PEQ on and off when I switched speakers, I bought a Klipsch R-120SW Subwoofer for $200 as an open box special on the Wal-Mart online third-party marketplace. That did an even better job overall. It also helped the Klipsch's some, too.

You can probably predict the story going forward: I quickly decided I needed MORE audio gear and systems. Fortunately, I had 2 more home offices at our other houses. Office #2 I decided to create what I dubbed the "1978 lower middle level drug dealer system" and bought a Marantz 2230 receiver (beautifully restored) on EBay and then in another slip down the slippery slope, a pair of Klipsch H2 Heresies from - drum roll - Facebook Marketplace. I also bought new an Ifi Zen DAC to source music via my computer.

Oh dear, once you start down the Facebook Marketplace road, things can happen fast. Two weeks later while at my Office #3, that as of yet didn't have a sound system beyond "computer speakers", I connected up on FB Marketplace with one of those guys with like 7 systems who are always switching stuff in and out and bought from him a set of B&W 702 S2s for a great price because they were mismatched colors! He also tossed in a cheap ADCOM GFA 7400 power amp and a probably slightly overpriced (but not badly) Theta Casa Nova preamp/DAC.

Keep on dear reader, I'm about to get to the SDA 2....

While doing my daily troll of FB Marketplace I stumbled across someone selling some "SDA Signature Reference System SRS 3.1 TL" speakers. I googled them and discovered the whole SDA rabbit hole which I promptly jumped into. SDA sounded cool and exotic and complicated and possibly really good-sounding. And being a tech-dude all of that appealed to me. This FBM example didn't look all that good in the pics and it was 3hr each way drive, so I kept looking. I pondered ordering something SDA off of ebay but shipping was atrociously expensive and the systems were pricey, too. But then somebody listed a "Polk SDA 2" for $140 "only" 2 hrs away. I reached out to him and 1) discovered he also had a set of Klipsch Tangent T500s (he didn't know the model, but I deduced it from the pics) for $240 to potentially upgrade my H2s at Office #2. And the real closer, he agreed to my proposal for him to meet me halfway for an additional $100. Yeah, I was taking a risk not listening to them, but at those prices, WTF?

So I drove home with two sets of BAS in the back of the Jeep. The T500s I quickly set up in Office #2 and they were good. I will indeed sell the H2s soon. The next weekend I hauled the SDA 2s over the mountain to house/office #1.

I found I had been a bit scammed. While dickering online with the seller I'd asked him if he had and was including the interface cable. He said yes. While we were transferring stuff at deal time, I asked about the cable, and he handed me a quite pristine long black cable, which I tossed in the back of the Jeep.

It was an Amazon Basics 15-foot optical cable! And he'd disappeared from FB. Also the near-virgin (it actually was!) ADCOM GFA 555 200 WPC power amp I'd ordered from ebay for the SDA 2s was delayed a day when an 18 wheeler (fortunately not the UPS truck) caught fire and blocked the only road into our region for several hours.

So I lost the day that I had dedicated on my calendar for setting up and experimenting with the the SDA 2. And I didn't have the interconnect cable. Double damn!

The next day in a 2 hour window I found I set up the SDA 2s and the ADCOM with a Wiim Pro Plus as the source and discovered the left speaker wasn't working. Dang.

Anyway the next day we were leaving for house #3 and my B&W 702 S2 based system for 9 days so the SDA project was on hold, not working.

When I got back to Office #1 I'd set aside considerable time to debug/fix the left SDA 2 speaker. As there was no sound at all, I figured the most likely scenario was that there was a broken connection somewhere. I imagined spending a fair bit of time going from connection to connection with the electrical meter until I found the problem.

I removed the post plate first, hoping it was something as simple as a bad connection there. I was running a low-power audio signal into the posts for detection purposes before I removed the screw holding the post plate. Seldom does debugging electronics go so well, but miraculously, as soon as I'd pulled the rather hairballish-looking plug of wiring out of the cabinet, I started getting sound from the left speaker!!!!!!

I did some balance checks and the left side sounded fine! I very carefully reinserted the wiring back into the cabinet and rescrewed the post plate and sure enough it continued to work. Some days you get lucky.

For the rest of the story read the first comment. This board has an OP character count limit.

memetic007

finishing the tale:

I fired that sucker up. Even without the interconnect cable, they sounded fantastic. Better than any of my systems other than the B&W 702 S2 system. Now I really wanted to find a cable!

I quickly found a cable for sale on Ebay for $30. That was a relief.

It took awhile to ship, so alas, we had to go over to house/office #2 (Klipsch Heresies and Tangent T500) for an extended stay before the cable arrived. We came over to House/Office #1 today for the day and the cable had arrived.

I played my reference list of tracks without the cable, then installed the cable.

Wow! The sound stage hugely popped. Like, I've never seen it before on an audio system. I'd remained suspicious of the left speaker, so I was regularly checking that it was still working. Amazingly once the SDA cable was connected I could absolutely NOT tell if the left (or for that matter the right) speaker was working. It all merged into an essentially speaker-free single audio sound stage hanging there.

So a long journey but in the end success. What sure seems to be real SDA sound for $140 plus $30 for the replacement cable.

treitz3

Hello and please allow me to offer you a very warm welcome to Club Polk. Success is awesome! After a brief stint with a Scott speaker, the Klipsch Heresy was one I listened too often as a kid. The SDA's are completely different.

Tom

F1nut

Nice story and welcome to Club Polk.

You paid $180.00 for those nasty SL2000 tweeters!?! Don't do that again

memetic007

>You paid $180.00 for those nasty SL2000 tweeters!?! Don't do that again

They don't sound terrible at all. But I will give an upgrade to RDO198 a try. So far I haven't done any mods and that seems a pretty straightforward one. Another extension of the hobby! Do the rabbit hole never end?

F1nut

The RD0(zero)198-1 is not the replacement for the SL2000. That would be the RD0(zero)194-1.

The SL2000 has a nasty 5dB spike @ 13kHz. Maybe you can't hear above 12kHz.

memetic007

Thx for the correction re: 198 v 194. I went back and checked and I ordered the 194s from Midwest.

>Maybe you can't hear above 12kHz.

Quite possibly. 70 years old, waaayyy too many 1970s rock-n-roll concerts, lots of big bore handgun shooting back in the day without adequate ear protection. We thought cigarette filters in the ears would do.

memetic007

>the SL2000 has a nasty 5dB spike @ 13kHz. Maybe you can't hear above 12kHz.

hmmm, maybe a simple Roon PEQ adjustment to lower the region around 13K by 5db would do the job. Will try over the weekend.

memetic007

@F1nut
Thanks: The SL2000 has a nasty 5dB spike @ 13kHz. Maybe you can't hear above 12kHz.

I spun up a Roon PEQ with a slope down to -5db starting at 12500 and at -5 at 13000. Makes a big difference!

My Polk 5 Roon PEQ that already had a sloping line from +9db at 20hz to 0 at 400hz. Adding the dip after 12500 really sounds good.