SDA-2B-TL & Recap Completed

[audiocr381ve]

First off, a massive thank you to all of you who helped me through this, even those of you who thought I shouldn't be within a miles radius of a soldering iron, but helped anyway. Again, thank you.

Here is what was accomplished. I'll list the parts I used for the next owner wanting to perform this modification/refreshment/upgrade, along with my first impressions.

Parts Used:

• (Two) 5.8uF Sonicap Gen I 200VDC (Matched Pair. Specifically ordered for the TL Mod which is a modification that allows the use of the better RD0-198 tweeter) $14 each
• (Two) 12.uF Sonicap Gen I 200VDC (Matched Pair) $20.45 each

• (Two) Mills MRA-12 0.5 ohm resistors $4.15 each
• (Two) Mills MRA-12 2.7 ohms $4.15 each
  
• (Six) 20uF Axon True Capacitor 250V 5% $4.31

The reason why six 20uF capacitors were used (for those who might be confused) is because each crossover has one position on the board that requires a 40uF capacitor. Many companies don't offer a 40uF capacitor (which in most cases would be massive anyway), so the idea is to parallel two 20uF capacitors to get the 40uF needed. There is also another position on each crossover the requires a 20uF capacitor in addition to the 40uF position. If your tracking with me, this equals the need for six 20uF caps.

25 ft. of Cardas Quad-Eutectic solder which was a whopping $6.

• Dynamat Extreme Speaker Kit $19.99 from Best Buy. This includes two sheets and was more than enough to cover both passive radiators and all four mid-drivers.

• JB Weld was about $6 - This is a paste that bonds and acts like a weld. Super strong stuff. The purpose of this was to prevent the magnet of the mid-drivers from moving thus causing a dead speaker.

• RD0-198 Tweeters $100

First Impressions:

Coming from a professional music background (recording, mixing, producing, writing), I know what I'm looking for in a speaker. I also know what a good recording sounds like. I play four instruments, I get timbre. I've tracked the drums in many different multi-million dollar facilities.

When I wired up my speakers for the first time after all the modifications, I was more than pleasantly surprised. I don't know who said they're gonna sound horrible at first...that wasn't my experience. If they get better from here, then just wow.

Somebody else mentioned that the cymbals after the TL Mod and Recap actually sound like cymbals now. As a professional drummer, I 100% agree! That was one of the first things I noticed. The cymbals are more bodied, like going from a cheap cigar to a genuine Cuban.

Vocals vocals vocals. Sweet, bodied, airy, open, DEEP. I don't know what else to say. The vocals are up front now, but not forward and exaggerated. Did I mention depth? I hear the instruments and vocalists like they're 10 feet into the wall! Soundstage is huge.

Another thing I noticed is uniformity. The speakers sound like they're working together better if that makes any sense.

I'm still waiting for the low-end to open up, I really hope it does. I like a speaker that has "punch" and that's something I've never experience with these speakers yet. It might be the only thing that's holding them back from being the perfect speaker (to me anyway).

I'll check everyday and do a write up. My Canare 4S11 speaker cable comes in tomorrow. I'm excited to see if the cable debate is true or not

[heiney9]

They will get a LOT better after about 200 hours of break in time. And then you may notice another minor improvement around the 500 hour mark. During the first 200 hours or so they may start to sound worse and then good and then worse, etc. Be patient grasshopper they will settle in.

Properly set-up and amplified they will give you "punch" and all the bass you could want. Clean, un-exaggerated bass, not bloated. If you are used to heavy, pounding, overpowering bass.....you won't get that. Just solid, organic, REAL bass. Coherence (uniformity), huge, open soundstage, vocals to die for and very non-fatiguing, proper decay, air, etc.

This entire upgrade/refresh is not a subtle change, as myself and others mentioned from the very beginning when you were so reluctant.

H9

[Joe08867]

We told you so!!!!

Like H9 said give them some time and they will open up even more. You may start to hear some brittleness from the top end at some point, it only last a little while and that bass slam you want is more to do with the equipment driving these guys than the speakers themselves. Polk SDA's are very solid in the bottom end.

The one thing I noticed after the update/upgrade is how detailed the instruments and locations were. I could almost see the bassist standing to the left of the drummer and like you said cymbals sound like they should or how us drummers hear them. Also listen to the snare drum. You will get that bit of slam/pop we hear playing.

Have fun, like fine wine they will just get better with time.

[sda2mike]

i did the upgrade a year ago april...they are much different speakers than when first upgraded...it took a while...now, with the right recording, no ac, no pool pump, at night, they are perfecto

thanks to ben

[TennMan]

Thanks audiocr381ve for posting the results of the improvements you made. I enjoyed reading it. Your background in music makes your report even better. Reading it makes me wish I had a pair of SDAs. (I'm looking) Keep us posted about the changes you hear during the break-in process.

They will get a LOT better after about 200 hours of break in time. And then you may notice another minor improvement around the 500 hour mark. During the first 200 hours or so they may start to sound worse and then good and then worse, etc.
H9

Although I'm not disputing that is true, I can't help but wonder why everyone reports that the cycling always stops with the speakers sounding their best. Is there a logical explanation for that happening? It would be like a Roulette wheel always stopping on Lucky 7 after bouncing around the loosing numbers.

[heiney9]

Although I'm not disputing that is true, I can't help but wonder why everyone reports that the cycling always stops with the speakers sounding their best. Is there a logical explanation for that happening? It would be like a Roulette wheel always stopping on Lucky 7 after bouncing around the loosing numbers.

This has been discussed almost as much as cables. Burn-in; some believe it, some don't. In all the projects I have done, said gear always changes character as new components settle in. That's my experience and it's been happening for years.

Some believe, some are on the fence, some think it's plausible and some are vehemently anti break-in.

I suggest your read many of the indepth posts by our own Darqueknight who did extensive tests on power cable break-in, with graphs and analysis. Or experience it for yourself to make your own decision.

H9

[Joe08867]

I like to thing of burn in as break in. If you have ever driven a brand new Jeep Wrangler you understand breaking in. Jeeps are notorious for having very stiff suspensions until they settle in. Just like new cars need some time to break in the engine, Audio components are no different.

[heiney9]

I say if we really want to discuss break-in burn-in (again) let's start another thread. Let's not take this thread off topic.

H9

[Joe08867]

Good Point H9.

[TennMan]

I say if we really want to discuss break-in burn-in (again) let's start another thread. Let's not take this thread off topic.

H9

I agree. I apologize for asking about burn-in in this thread even though it had been brought up already in the discussion. I don't want the hounds of hell chasing me because I seemed to go against the grain a little..

[Joe08867]

That's it,

RELEASE THE KRACKEN!!!!!!

[heiney9]

I agree. I apologize for asking about burn-in in this thread even though it had been brought up already in the discussion. I don't want the hounds of hell chasing me because I seemed to go against the grain a little..

Not a problem at all...........it's just if the discussion is going to continue it's better to start another thread. The subject is certainly within the scope of this thread, but before it starts to get too heated it's best to move it to it's own area. IMO.

H9

[nspindel]

Congrats on finishing the work, nice job. They will definitely get even better as you approach that 200 hour mark, as others indicate. I've done two pairs of SDA's in Sonicaps and both improved a lot with the break in process.

I'm still waiting for the low-end to open up, I really hope it does. I like a speaker that has "punch" and that's something I've never experience with these speakers yet. It might be the only thing that's holding them back from being the perfect speaker (to me anyway).

If you're serious about getting the punch you're looking for out of your SDA's, the inductor is the thing to do. I have the Erse iron core inductors in my 1C's, they helped a lot. DarqueNight turned me on to the Solen air cores, which I'm going to use in my CRS+'s when I do them. The Erse inductors are fairly affordable, I think the pair will cost you around $60 from Parts Express. Lowering the DCR of the inductor will benefit your bass slam, there's a few threads where Matt Polk provides a few paragraphs about how the higher DCR inductor was used as protection for a lot of amps available in the days when the SDA's were in production. Many amps couldn't handle the current requirements that result from lowering the resistance of the inductor. Modern amps are generally capable of handling the higher current, and the bass performance definitely improves with the mod.

[audiocr381ve]

They will get a LOT better after about 200 hours of break in time. And then you may notice another minor improvement around the 500 hour mark. During the first 200 hours or so they may start to sound worse and then good and then worse, etc. Be patient grasshopper they will settle in.

Properly set-up and amplified they will give you "punch" and all the bass you could want. Clean, un-exaggerated bass, not bloated. If you are used to heavy, pounding, overpowering bass.....you won't get that. Just solid, organic, REAL bass. Coherence (uniformity), huge, open soundstage, vocals to die for and very non-fatiguing, proper decay, air, etc.

This entire upgrade/refresh is not a subtle change, as myself and others mentioned from the very beginning when you were so reluctant.

H9

Impressions after 10 hours:

The Blue Jeans Canare 4S11 came in early this morning (woke me up!). The first thing I did was swap cables.

The cable might be contributing to this, but H9 was absolutely correct in his observations. Things are sounding a little funky this morning (could also be that my wife and I got into an argument this morning too). I'm not talking Tower of Power funky either.

I want to be careful and not read into things to much, because I can most certainly be over-analytical, but I'm playing some Miles Davis King of Blue and the trumpet is CUTTING through. The trumpet should cut through, but it shouldn't cut my ear drum in half. They aren't as soft and smooth as they were last night.

After hearing what I heard last night, it doesn't matter. I'll be patient and let things rock n' roll

Thanks audiocr381ve for posting the results of the improvements you made. I enjoyed reading it. Your background in music makes your report even better. Reading it makes me wish I had a pair of SDAs. (I'm looking) Keep us posted about the changes you hear during the break-in process.

Although I'm not disputing that is true, I can't help but wonder why everyone reports that the cycling always stops with the speakers sounding their best. Is there a logical explanation for that happening? It would be like a Roulette wheel always stopping on Lucky 7 after bouncing around the loosing numbers.

You got it. SDA's are super fun. It's all about that depth. I've never heard anything like it.

We told you so!!!!

Like H9 said give them some time and they will open up even more. You may start to hear some brittleness from the top end at some point, it only last a little while and that bass slam you want is more to do with the equipment driving these guys than the speakers themselves. Polk SDA's are very solid in the bottom end.

The one thing I noticed after the update/upgrade is how detailed the instruments and locations were. I could almost see the bassist standing to the left of the drummer and like you said cymbals sound like they should or how us drummers hear them. Also listen to the snare drum. You will get that bit of slam/pop we hear playing.

Have fun, like fine wine they will just get better with time.

Fellow drummer?! Nice man. I take back all my sarcasms towards you in the other thread! :tongue:

You're making me think a new amp is in order very soon. We'll see!

Congrats on finishing the work, nice job. They will definitely get even better as you approach that 200 hour mark, as others indicate. I've done two pairs of SDA's in Sonicaps and both improved a lot with the break in process.



If you're serious about getting the punch you're looking for out of your SDA's, the inductor is the thing to do. I have the Erse iron core inductors in my 1C's, they helped a lot. DarqueNight turned me on to the Solen air cores, which I'm going to use in my CRS+'s when I do them. The Erse inductors are fairly affordable, I think the pair will cost you around $60 from Parts Express. Lowering the DCR of the inductor will benefit your bass slam, there's a few threads where Matt Polk provides a few paragraphs about how the higher DCR inductor was used as protection for a lot of amps available in the days when the SDA's were in production. Many amps couldn't handle the current requirements that result from lowering the resistance of the inductor. Modern amps are generally capable of handling the higher current, and the bass performance definitely improves with the mod.

Awesome idea. I'm gonna let these thangs break in, and then I'm gonna break back in and perform this last mod. For me, that's the only thing missing. The low-end is THERE, but the punch is not.

Which Erse inductors are they?

[inspiredsports]

Nicely done. My experience with this mod is that the speakers keep sounding better and better as the crossovers break in. Further, better components don't seem to exceed the capabilities of TL'd 2B's. They are keepers!

[heiney9]

Don't change inductors until you've had a long listening time on the current mods. I'm in no way discounting the inductor change, but I have all the bass I could possibly want in my set-up and I fear doing the inductors would put it over the edge.

Let the current mods settle in and get some listening time on them and then decide, say in 3 months if you want to swap inductors.

Patience grasshopper

H9

[audiocr381ve]

Don't change inductors until you've had a long listening time on the current mods. I'm in no way discounting the inductor change, but I have all the bass I could possibly want in my set-up and I fear doing the inductors would put it over the edge.

Let the current mods settle in and get some listening time on them and then decide, say in 3 months if you want to swap inductors.

Patience grasshopper

H9

Haha.

It's that "PUNCH" though. Deep bass is awesome. Kick drum punch is hardly there. I've had bookshelf speakers put out more punch! I also have a terrible room with tile floors and a ceiling that I can just about touch if I put my hand up.

I'll give it 2 weeks

[jcandy]

Don't change inductors until you've had a long listening time on the current mods. I'm in no way discounting the inductor change, but I have all the bass I could possibly want in my set-up and I fear doing the inductors would put it over the edge.

Let the current mods settle in and get some listening time on them and then decide, say in 3 months if you want to swap inductors.

I agree with this. The bass response of the SDA2B (at least in stock form) is ever-so-slightly peaked at low frequency, so adding more peaking by lowering inductor DCR probably amounts to some degree of coloration. That said, depending on your room size, reflectivity, you may prefer to change the response curve slightly. Perhaps a more systematic, less invasive, way to do this would be active bass equalization. Or, at the crossover end, you might want to experiment with padding the new tweeters down even more. This is one reason why I no longer use solder for crossover connections; rather, I use terminal blocks:



This way, swapping padding (series and shunt) resistors in and out takes a few seconds. Here is a comparison of the measured response on the speakers you heard at my place. The first is a 5 Ohm shunt resistor and the second is a 7 Ohm resistor:

[heiney9]

Haha.

It's that "PUNCH" though. Deep bass is awesome. Kick drum punch is hardly there. I've had bookshelf speakers put out more punch! I also have a terrible room with tile floors and a ceiling that I can just about touch if I put my hand up.

I'll give it 2 weeks

Believe me once the low pass Aeon caps break in a bit you'll get the "punch". When I did my 5B's, same exact thing...........where did the bass go? I came back better than ever.

H9

[sda2mike]

Believe me once the low pass Aeon caps break in a bit you'll get the "punch". When I did my 5B's, same exact thing...........where did the bass go? I came back better than ever.

H9

h9 is 100% correct! my 2b's sounded thin, then full, then back to 'no punch'..now, they got bottom they aint cerwin vega's, that's for sure...they are smooth...no part of the bandwith outshines any other part. in other words, they produce killer bass without being obvious about it..make sense?

let them mellow in or out..just give 'em some time



mike

[DarqueKnight]

Coming from a professional music background (recording, mixing, producing, writing), I know what I'm looking for in a speaker. I also know what a good recording sounds like.

A trained ear helps out a lot.

I play four instruments, I get timbre. I've tracked the drums in many different multi-million dollar facilities.

When I wired up my speakers for the first time after all the modifications, I was more than pleasantly surprised. I don't know who said they're gonna sound horrible at first...that wasn't my experience. If they get better from here, then just wow.

I assume you are getting some emotional thrills? This is important because the generation of emotional thrills is a design specification of stereophonic home audio systems.

BTW, I am a saxophone player.

Somebody else mentioned that the cymbals after the TL Mod and Recap actually sound like cymbals now. As a professional drummer, I 100% agree! That was one of the first things I noticed. The cymbals are more bodied, like going from a cheap cigar to a genuine Cuban.

In other words, more like real music?

Vocals vocals vocals. Sweet, bodied, airy, open, DEEP. I don't know what else to say. The vocals are up front now, but not forward and exaggerated. Did I mention depth? I hear the instruments and vocalists like they're 10 feet into the wall! Soundstage is huge.

Careful now, you're starting to sound like one of those audio magazine reviewers.

Another thing I noticed is uniformity. The speakers sound like they're working together better if that makes any sense.

It makes perfect sense to me and others who have heard the same things. A detailed, coherent sound stage is one of the basic performance parameters of stereophonic audio.

I'm still waiting for the low-end to open up, I really hope it does. I like a speaker that has "punch" and that's something I've never experience with these speakers yet. It might be the only thing that's holding them back from being the perfect speaker (to me anyway).

With SDA's, bass quality will depend a lot on the high current capability of your amplifier.

My Canare 4S11 speaker cable comes in tomorrow. I'm excited to see if the cable debate is true or not

Thanks for sharing your listening impressions. Congrats on your good results.

[nspindel]

Which Erse inductors are they?

http://www.parts-express.com/pe/psho...number=266-954

[nspindel]

The bass response of the SDA2B (at least in stock form) is ever-so-slightly peaked at low frequency, so adding more peaking by lowering inductor DCR probably amounts to some degree of coloration.

Lower DCR inductor is a Matthew Polk endorsed upgrade.

[Toolfan66]

WOW!! that was fast, took about 1-1/2 weeks to get your parts and installed..

[jcandy]

Lower DCR inductor is a Matthew Polk endorsed upgrade.

Yes, I know. Nevertheless, there are well-known and well-discussed caveats to this particular modification, which is not in any way a guaranteed improvement as suggested in h9's post. You can also read the thread below for more details:

http://www.polkaudio.com/forums/showthread.php?t=109611

[heiney9]

I will add that 1) my suggestion would go for any recent modification to wait until the dust settles so to speak before furthur modification. 2) I would take Matthew Polk's recommendation over a "general" recommendation since he is the one who built the SDA line and has extensive knowledge and experience with that speaker.

As always, one's mileage may vary.

H9

P.s. my recommendation in no way precludes me from trying different inductors. I just moved into a new house and I need to listen to the rig where it's at to get a baseline and evaluate, and then decide on my course of action to tweak my listening evnironment. I've already compensated a bit by rolling in less aggressive tubes because my room is "lively". Next up is room treatments w/my favorite tube back in place.

[inspiredsports]

I will add that 1) my suggestion would go for any recent modification to wait until the dust settles so to speak before furthur modification. 2) I would take Matthew Polk's recommendation over a "general" recommendation since he is the one who built the SDA line and has extensive knowledge and experience with that speaker.

As always, one's mileage may vary.

H9

P.s. my recommendation in no way precludes me from trying different inductors. I just moved into a new house and I need to listen to the rig where it's at to get a baseline and evaluate, and then decide on my course of action to tweak my listening environment. I've already compensated a bit by rolling in less aggressive tubes because my room is "lively". Next up is room treatments w/my favorite tube back in place.

I agree 100%.

When I first became re-interested in this hobby, I tried for it all in one jump and ended up having to redo a few things because I skipped a step or two and then had to go back and learn what those steps really contributed.

I am constantly amazed by the powerful bass 2B's can reproduce.

[audiocr381ve]

Thanks for all the help and info. I will take all things into consideration.

I agree 100%.

When I first became re-interested in this hobby, I tried for it all in one jump and ended up having to redo a few things because I skipped a step or two and then had to go back and learn what those steps really contributed.

I am constantly amazed by the powerful bass 2B's can reproduce.

Did you have the inductors replaced? It's weird, I just haven't experienced this yet. I'm beginning to think it's a room issue.

[nspindel]

I've already compensated a bit by rolling in less aggressive tubes because my room is "lively". Next up is room treatments w/my favorite tube back in place.

Changing tubes around are you?

[Toolfan66]

I have yet to hear a set of SDA's that lack bass, stock or upgraded.

SDA CRS+'s/2B's/1C's/2.3's/2.3tl's/SDA-SRS's/1.2's/1.2tl's

My guess is placement/power or both. also do you have these spiked?? getting them off the floor is HUGE