just picked up a mint pair of SDA2B's and I'd like to bring them up to date (rebuild the crossovers)

91rtstealth

gmcman wrote: »

I would stick with all Sonicaps if you're going that route. Once you get the crossovers rebuilt, listen for a few hundred hours then once they settle in, upgrade your internal wiring....should be a noticeable improvement again.

I'm still debating, but I think I might just pop one of my rdo194's in them from my sda1b's (because the sl2000's are too harsh for me) listen to them as is for a while, get to know them as is, then do the full upgrade with sonicaps once I have the extra cash to do so. That way I can hopefully notice a big difference. In the mean time, I can start tearing my sda1's apart and rebuilding their crossovers. I'll be getting my JBL 4425's to Florida from PA soon, so those will most certainly tie me over in the mean time

F1nut wrote: »

Many say that shunt caps don't matter. I strongly disagree.

what exactly are shunt caps anyways?

westmassguy

91rtstealth wrote: »

gmcman wrote: »

I would stick with all Sonicaps if you're going that route. Once you get the crossovers rebuilt, listen for a few hundred hours then once they settle in, upgrade your internal wiring....should be a noticeable improvement again.

I'm still debating, but I think I might just pop one of my rdo194's in them from my sda1b's (because the sl2000's are too harsh for me) listen to them as is for a while, get to know them as is, then do the full upgrade with sonicaps once I have the extra cash to do so. That way I can hopefully notice a big difference. In the mean time, I can start tearing my sda1's apart and rebuilding their crossovers. I'll be getting my JBL 4425's to Florida from PA soon, so those will most certainly tie me over in the mean time

F1nut wrote: »

Many say that shunt caps don't matter. I strongly disagree.

what exactly are shunt caps anyways?

In a 2nd order crossover, the shunt or bypass capacitor allows a much steeper cutoff at the crossover frequency. It helps by bleeding off more of the higher frequencies before the signal reaches the woofer.
A 1st order crossover is 6dB per octave. A 2nd order crossover is 12dB per octave.

91rtstealth

ok..I can see how that would make a noticeable difference. I think I'm just gonna save up the money and do it right, however, I really want to do my sda1b's too. In fact, I want to do those more because I've grown attached to them.

Is that a whole other rabbit hole or is it fairly similar to the 2's? I would likely just keep the rdo194's I have in them currently. I don't really think spending another $200 on the 198's is worth it to me.

F1nut

It's more than worth it.

westmassguy

1Bs are a whole different ball game. Split crossovers and very large value caps in the sub base drive circuit.

91rtstealth

westmassguy wrote: »

1Bs are a whole different ball game. Split crossovers and very large value caps in the sub base drive circuit.

what does this mean for me? haha. Ideally, I'd like to recap both pairs of speakers, but if I had to choose....i'd probably want to recap the 1's.

txcoastal1

The 2bs will be our new favorites

pitdogg2

txcoastal1 wrote: »

The 2bs will be your new favorites

Fixed it for you.

SDA 2b are 4th generation where 1b is 2nd gen. Just being able to use the RD-0198 is a great bonus. My 2.3tl's used the SL3000 which is not a bad tweeter but the 198's just left them in the dust. I was shocked how much better they were. So going from the SL2000 to 198's will be stellar. Bank in that.

91rtstealth

txcoastal1 wrote: »

The 2bs will be our new favorites

pitdogg2 wrote: »

txcoastal1 wrote: »

The 2bs will be your new favorites

Fixed it for you.

SDA 2b are 4th generation where 1b is 2nd gen. Just being able to use the RD-0198 is a great bonus. My 2.3tl's used the SL3000 which is not a bad tweeter but the 198's just left them in the dust. I was shocked how much better they were. So going from the SL2000 to 198's will be stellar. Bank in that.

haha....everyone keeps saying this, which is the only reason I'm going to upgrade the 2's. I initially just bought them to try them out and compare them with my 1's. Plus, I kept seeing on here how everyone loves to modify the 2's and not the 1's and I wanted to find out why. I think ya'll finally talked me into this...i'm even considering selling my kef 103.2's that I barely use to pay for the upgrade.

in regard to the tweeters, I did notice a big difference going from sl2000 to rdo194 in my sda1's. I was surprised by that.

so...can someone really tell me why the 2's are "better" than the 1's. I just assumed the 1's would be the way to go with twice the drivers and being the "higher" model. I did notice that my 2b's have the better mid drivers in them (6503 and 6511)...otherwise, I don't know what makes them so much better. Enlighten me....

Lastly, I still would like to recap the 1's because apparently I'm not really hearing what they are capable of. Any suggestions on that?

pitdogg2

On my SDA 1 Signature the two lower drivers are bass. One upper is dimensional one is stereo. In the 2b they basically found a way to do all that with two drivers. On my SDA 1 signatures they were basically the same configuration as SDA1b but had a stereo and dimensional tweeter i disabled the dimensional. Yes they seemed to have more bass but my SDA2a's had a much better and larger stage presentation. I'm sure you will find the same between your two.

I'm sorry I was trying too do too many things at one time here. and hit go prematurely.

Since the SDA1b used all MW 6509 I'm assuming they were like my SDA1 signatures as they also used all MW6600 or MW6501 you may be correct in your assertation as how they are more like SDA1c in that configuration. I've looked at the schematic but they do not break down the drivers as stereo, dimensional or bass like some others

SDA1a

https://us.v-cdn.net/5021930/uploads/attachments/1/8/5/1/1/31012.pdf

SDA1c

https://us.v-cdn.net/5021930/uploads/attachments/1/8/5/1/1/72432.pdf

SDA1b

https://us.v-cdn.net/5021930/uploads/attachments/1/8/5/1/1/31011.pdf

91rtstealth

pitdogg2 wrote: »

On your 1b the two lower drivers are bass. One upper is dimensional one is stereo. In the 2b they basically found a way to do all that with two drivers. On my SDA 1 signatures were basically the same configuration but had a dimensional tweeter i disabled. Yes they seemed to have more bass but my SDA2a's had a much better and larger stage presentation. I'm sure you will find the same between your two.

ok now that's very interesting..I didn't know that's how the 4 drivers worked on my 1's. I thought the two on the left were dimensional, and the two on the right were stereo (referring to the left speaker).

I'm a bass head, but I love a huge sound stage, which is why I like these speakers so much in the first place. I still can't get over the sound stage. I've been a musician for 29 years and the fact that I can almost "see" the band while I'm listening to music is super awesome to me. Anyways, if I want more bass, i'll get a sub. I don't think I'll want more bass and my neighbor definitely won't want more bass either.

Anyways, I'm anxious to compare them to my JBL 4425's when I get them back. They were my favorite speakers I owned when I was living in PA. Since I moved to FL, I got these Polks and I think they might actually be my favorite thus far. I will find out soon. One day I'll get all my gear down here. I really want to compare them to a pair of JBL L250 (best sounding speakers i've heard to date), L220's, and Vandersteens.

Schurkey

westmassguy wrote: »

1Bs are a whole different ball game. Split crossovers and very large value caps in the sub base drive circuit.

But despite the "whole different ball game" they respond very well to the usual crossover upgrades.

91rtstealth wrote: »

I'd like to recap both pairs of speakers, but if I had to choose....i'd probably want to recap the 1's.

I love my 1Bs. Rebuilt the crossovers, fixed some other issues years ago, and never once regretted it. That said, I do wish they could be used with bridged amps, and for all practical purposes, they can't.

pitdogg2 wrote: »

SDA 2b are 4th generation where 1b is 2nd gen. Just being able to use the RD-0198 is a great bonus. My 2.3tl's used the SL3000 which is not a bad tweeter but the 198's just left them in the dust. I was shocked how much better they were. So going from the SL2000 to 198's will be stellar. Bank in that.

SDA 1B is 3rd Gen, not 2nd. No SDA tweeter, and the SDA mid-woofers also reinforce the bass. The only real downside is the lack of compatibility with bridged/balanced amps, as they don't work with an isolation transformer in the SDA interconnect cable.

There's a long thread about putting 198s into SRS 2 pin/blades which are electrically the equivalent to the 1B. I did. I like it. The thread doesn't get "good" until about half-way through.
https://forum.polkaudio.com/discussion/74946/sda-srs-2-crossover-parts-list/p1

Others disagree that it can be done--which is fine. I'm not going back, though.

Schurkey

91rtstealth wrote: »

pitdogg2 wrote: »

On your 1b the two lower drivers are bass. One upper is dimensional one is stereo. In the 2b they basically found a way to do all that with two drivers. On my SDA 1 signatures were basically the same configuration but had a dimensional tweeter i disabled. Yes they seemed to have more bass but my SDA2a's had a much better and larger stage presentation. I'm sure you will find the same between your two.

ok now that's very interesting..I didn't know that's how the 4 drivers worked on my 1's. I thought the two on the left were dimensional, and the two on the right were stereo (referring to the left speaker).

That's NOT how the driver's work in the 1B. and the post has been edited somewhat to reflect some correction. It may be how the drivers work in the 1, 1 Signature, and 1A.
With the 1B, the inside pair of drivers are "stereo". Outside pair of drivers are SDA + stereo bass reinforcement. Two tweeters, one "primary" and one with additionally-restriced frequency response.

I would expect the 1B to have deeper, "better" bass than the 2B. Of course, bass is known to be room-dependent so the room and speaker location may make more difference than the speakers themselves.

westmassguy

Schurkey wrote: »

westmassguy wrote: »

1Bs are a whole different ball game. Split crossovers and very large value caps in the sub base drive circuit.

But despite the "whole different ball game" they respond very well to the usual crossover upgrades.

I wasn't disputing that, merely pointing out that it's a split crossover, not a single board, and will be more expensive to upgrade than the 2B

91rtstealth

Schurkey wrote: »

91rtstealth wrote: »

pitdogg2 wrote: »

On your 1b the two lower drivers are bass. One upper is dimensional one is stereo. In the 2b they basically found a way to do all that with two drivers. On my SDA 1 signatures were basically the same configuration but had a dimensional tweeter i disabled. Yes they seemed to have more bass but my SDA2a's had a much better and larger stage presentation. I'm sure you will find the same between your two.

ok now that's very interesting..I didn't know that's how the 4 drivers worked on my 1's. I thought the two on the left were dimensional, and the two on the right were stereo (referring to the left speaker).

That's NOT how the driver's work in the 1B. and the post has been edited somewhat to reflect some correction. It may be how the drivers work in the 1, 1 Signature, and 1A.
With the 1B, the inside pair of drivers are "stereo". Outside pair of drivers are SDA + stereo bass reinforcement. Two tweeters, one "primary" and one with additionally-restriced frequency response.

I would expect the 1B to have deeper, "better" bass than the 2B. Of course, bass is known to be room-dependent so the room and speaker location may make more difference than the speakers themselves.

ok I was gonna say....whenever I listened to each driver, it seemed like they were working as you put it. And yes, I the bass is noticeably better on my 1's, which is probably why I prefer them thus far. That, and they look badass with all those drivers.

F1nut

1B - overall FR, 14Hz to 26kHz. Efficiency 92 dB
2B - overall FR, 15Hz to 26kHz. Efficiency 90 dB.

windstriker

Have both speakers passed the pr test? Not having the 2bs sealed as well as the other ones would put the 2bs at a disadvantage.

91rtstealth

I can only assume the PR test is to push in the passive radiator inwards and see how long the mid/bass drivers stay outwards?

91rtstealth

ok..I've literally been listening to my SDA1's and 2's all day with my newly refurbished McIntosh MC7270. I still think I prefer the 1's, but the 2's are growing on me. I just think my 1's have a bigger/deeper sound stage and bigger bass and crisper treble. I took one of the rdo194's from my 1's and popped it into my 2's and i've been listening for hours. They are growing on me.

I think I might sell my Kef 103.2's for the cash to upgrade my SDA2's...I sure hope it's worth it

91rtstealth

hey guys..I was just blasting my sda2's and the treble rolled off randomly and when I turned my amp back up, it came back....trying to figure out whether it was my amp or the speakers...is that what the polyswitches do? I'm not sure how they work and this has never happened before...

F1nut

That's the function of a polyswitch.

westmassguy

The polyswitch is being tripped. It resets automatically when it cools down. Either you're overdriving the 2Bs, or the polyswitch is bad

txcoastal1

westmassguy wrote: »

The polyswitch is being tripped. It resets automatically when it cools down. Either you're overdriving the 2Bs, or the polyswitch is bad

Or both

91rtstealth

Interesting. I never ran into that in my sda1’s before. It was super weird and I didn’t know what the heck was going on. I just heard the treble being ruduced but not removed entirely. Honestly, I wasn’t cranking it absurdly loud so there’s another reason to remove the poly switch. I actually blew one of my rdo194’s yesterday. I took two of them from my 1’s and put them in my 2’s temporarily. I was jamming away yesterday and one of them started buzzing. 😔

Nightfall

91rtstealth wrote: »

Interesting. I never ran into that in my sda1’s before. It was super weird and I didn’t know what the heck was going on. I just heard the treble being ruduced but not removed entirely. Honestly, I wasn’t cranking it absurdly loud so there’s another reason to remove the poly switch. I actually blew one of my rdo194’s yesterday. I took two of them from my 1’s and put them in my 2’s temporarily. I was jamming away yesterday and one of them started buzzing. 😔

You are cranking it too loud. You're tripping polyswitches and killing tweeters. I would personally suggest not removing the polyswitches in this case.

pitdogg2

He'll need some new ones if he keeps them in circuit.

F1nut

91rtstealth wrote: »

Interesting. I never ran into that in my sda1’s before. It was super weird and I didn’t know what the heck was going on. I just heard the treble being ruduced but not removed entirely. Honestly, I wasn’t cranking it absurdly loud so there’s another reason to remove the poly switch. I actually blew one of my rdo194’s yesterday. I took two of them from my 1’s and put them in my 2’s temporarily. I was jamming away yesterday and one of them started buzzing. 😔

Again, your 1B's have an efficiency rating of 92dB. Your 2B's are 90dB. It takes double the power for a 3dB increase in volume, so to play the 2B's at close the same SPL as the 1B's your amp has to almost double the output, which appears to be causing the amp to send clipped signals. In other words, your amp is likely gassed.

Are you using tone controls?

91rtstealth

F1nut wrote: »

91rtstealth wrote: »

Interesting. I never ran into that in my sda1’s before. It was super weird and I didn’t know what the heck was going on. I just heard the treble being ruduced but not removed entirely. Honestly, I wasn’t cranking it absurdly loud so there’s another reason to remove the poly switch. I actually blew one of my rdo194’s yesterday. I took two of them from my 1’s and put them in my 2’s temporarily. I was jamming away yesterday and one of them started buzzing. 😔

Again, your 1B's have an efficiency rating of 92dB. Your 2B's are 90dB. It takes double the power for a 3dB increase in volume, so to play the 2B's at close the same SPL as the 1B's your amp has to almost double the output, which appears to be causing the amp to send clipped signals. In other words, your amp is likely gassed.

Are you using tone controls?

nah..I usually keep things flat unless the recording is weak in bass. I never turn the treble beyond 0. In fact, if I ever use the treble adjustment, it's to dial some out. I don't like super bright audio. I can't stand it actually.

I'm currently powering them with a McIntosh MC7270 which should be sufficient to power them, yes? and with the power guard, I should be getting any "clipped" signals to the speakers.

In regard to playing them too loud, I wasn't playing them unreasonably loud. I'm super cautious about damaging my ears (I'm a professional musician, I need my ears). I'm not sure what's going on, but whatever...i'll be fully redoing those crossovers and buying rdo198's soon anyways.

Nightfall

Is it possible the 194 that died was just faulty?

F1nut

Ok, found the power specs for your amp. Stereo: 270W+270W (1ohm, 2ohm, 4ohm, 8ohm), which should be plenty of juice and you're not cranking the bass control, so I'd have to say something else is going on.