how do Polk SDA 1B compare to SDA 2B?

pglbook

I recently had a friend visit from out of town and, while here, he fell in love with my Polk SDA 2B TL speakers and told me he would look for a pair when he got back home. My friend called yesterday and told me he came across a pair of SDA 1Bs near him and asked me how they compared to my SDA 2Bs.
i could not answer him because I have never owned or heard any of the other SDA models but I told him not to fear, that my fellow Polkies on this site would be able to let me know so I could pass along the information to him.

Are the SDA 1Bs one of the better models in the SDA line?
How do SDA 1Bs compare to 2Bs?
Should I tell my friend to get the 1Bs or wait for a pair of 2Bs since he has heard what the 2Bs sound like and loved the SDA 2Bs (although my 2Bs are TL'd and not stock 2Bs)?

Thanks.

Mystery

1B's have twice the drivers except PR so I'd go for 1B's over 2B's but I've never heard of 1B's so that's not much of an opinion.
But I really think 2 stereo and 2 dimensional drivers will deliver more midrange for sure.
Unless 1B's are really designed in a bad way, they should be better than 2B's but wait for the gurus' opinions here. :redface:

gdb

Telling your friend to join Club Polk would be the greater service/kindness.

ken brydson

gdb wrote: »

Telling your friend to join Club Polk would be the greater service/kindness.

Unless he values his friends finances...

zarrdoss

Do you know the asking price and condition? there are pros and cons to both, I would mod what ever ones he gets, the 2b's are cheaper to mod than the 1b's. Unless you like playing at ear splitting levels they will be fine. The 1b's should give you more sound and more SDA effect. If he likes what he hears and the condition and asking price is good I say go for it.

PolkieMan

1B are 4 ohms, older model Third Gen,1986 to 1987, and don't have the nice crossover boards. $250 in good condition.

inspiredsports

The 1B can be upgraded to use RDO-198's (TL'd), but you have something in the neighborhood of 4 times the capacitance to replace/fund to do so. Very few have done this, but the sound becomes quite good.

The single source point tweeter sound of a TL'd 2B is extremely pure and hard to beat; truly exceptional. I disagree the soundstage / SDA effect is better with the 1B. It might be a limitation of the older MW6509's in the 1B, but the MW6503 / MW6511 pairing in the 2B give the 2B a slight advantage in soundstage, in my humble opinion.

The TL'd 2B's also seem more versatile with both tube and SS amps where the 1B's seem to fare best with SS.

sda2mike

i've heard 1c's are the '1' to get and later 2b's are the best of that line..

inspiredsports

sda2mike wrote: »

i've heard 1c's are the '1' to get and later 2b's are the best of that line..

Exactly. The 1C versus 2B is a very tough call. These are pinnacle models if you can't afford $$'s or space to "go all the way" with the big boys.

westmassguy

PolkieMan wrote: »

1B are 4 ohms, older model Third Gen,1986 to 1987, and don't have the nice crossover boards. $250 in good condition.

Agreed.I would add that he will need a quality amp capable of 4ohms and less. My 2As from the same generation dropped to 3.5 ohms before my upgrades, and now are closer to 3 ohms below 150 Hz. The crossovers are indeed more expensive to upgrade than the 4th generation 2Bs, but if the condition is good, and he can get them for a good price, he'll have a very fine pair of SDAs to be sure.

pglbook

Thanks everyone. I knew I'd get lots of great info and advice for my friend and I will pass it along.

gdp, I did tell my buddy about Club Polk and told him he needs to join but he just wanted me to ask for now.
I am sure once he gets a pair of Polks - whatever model - he will be hooked and will join up.

zarrdoss, he said they were in nice condition, all original, and that the asking price was $300.

PolkieMan, that's a good point about the 1Bs being 4 ohm and I will let my friend know he willl need a good power amp to drive them.

I will pass along the info and let him decide.

Thanks again to all.

naturallight

If he likes your 2B's he would probably love a set of 1C's. They are a tad easier on a power amp as there 6 ohm speakers. BUT..you run into some problems. Again 1C's need a good high current, high power amp. Size of the room he's going to put them in is another issue. If he's NOT going to push them...may not be an issue, but they tend to act more like the big boys and run out of "breathing" room if pushed. At least my 1C's do. The last but not least issue is, he heard your 2B's which are TL'ed. He's going to have to change out the tweeters. There NOT going to sound like yours.

westmassguy

naturallight wrote: »

If he likes your 2B's he would probably love a set of 1C's. They are a tad easier on a power amp as there 6 ohm speakers. BUT..you run into some problems. Again 1C's need a good high current, high power amp. Size of the room he's going to put them in is another issue. If he's NOT going to push them...may not be an issue, but they tend to act more like the big boys and run out of "breathing" room if pushed. At least my 1C's do. The last but not least issue is, he heard your 2B's which are TL'ed. He's going to have to change out the tweeters. There NOT going to sound like yours.

He's considering 1Bs, not 1Cs. 1Bs are 4 ohm, not 6, and are a tougher load than your 1Cs.

naturallight

Pretty much why i said it. Rather then buy the 1B's...he would be better off finding 1C's ..IF he wants to go that route.

pglbook

Thanks, everyone. I passed along the info to my friend and he told me he will wait for either a 1C or 2B to come along.
Thanks for the great advice. I think it was a good decision on his part because the 1Bs were a tad on the high end in terms of price and he would rather wait on something he'd be happier with than rush into things. Thanks again. And hopefully he will join this forum as I keep on telling him how great it is.

naturallight

LMAO..well if 300 bills is too much...take 1C's off the table right now. To get a good working set of 1C's at this point...your looking at alot more then that, plus the room he's going to put them in, and the power amp.

teekay0007

Where's tophatjohnny on this one? I thought he'd be all over it. He had a pair of 2Bs - as well as a pair of CRS+s - and opted for the 1Bs. Last I'd heard, he'd done some upgrades/mods (all except redoing his XO's and spiking them) to the 1Bs and was in aural bliss. :cool:

And, oh yeah...prior to doing the 1B mods, he also gave some 3.1TLs an 8-minute audition (:razz:) before selling them to his neighbor.

naturallight

Let me put things this way. Dependent on the size of the room, what equipment your "bud" is running..will pretty much determine what speakers he should buy.

Back in 1987 1C's speakers were i think close to 1600 bucks...

Point 1 1C's will not work well off a receiver..period. Point 2, if there not put in a descent size room..not going to work that great ..IF you push them.



IF you have the right size room, and the right power to push them...they will eat new $1600 buck towers for breakfast. I know, i have have tried them..even unmodded. If you mod them. you would have to pay well over 2K to even come close.



If I put RDO's in my 1C's....I would never sell them for less then $600 if i sold them at all.

The problem is room and equipment..thats what your Friend needs to know before he jumps down the rabbit hole of stereo.

Mr. Bubbles

You will get a lot of opinions on this and also many great facts that don't directly answer your initial question.

Let me first say that all SDA's are great speakers (except possibly first gen. models with dimensional tweets; I have never heard any of those to judge). As I have said (as well as many others) before. If a set of SDA's comes your way at a good pirce, buy them. Period! Will they be your perfect model? Maybe , maybe not. If a different model comes your way later, get them and decide between the 2. I have several different modles and have heard more, and am still of that opinion. The SDA's are just getting too hard to come by at good deales to turn away. If you want SDA sound.

That being said, I own the 2A's, 1C's, SRS's, and 1.2TL's and my favorites (from a purely sound standpoint) are the 2A's, with my least favorite being the 1C's. Individuals must judge for themselves which they like better but if they let a model pass them by they may not be able to do that.

Good luck to your friend.

naturallight

Yeah.. I do tend to agree with Mr Bubbles..in a certain respect. the cost of GOOD SDA speakers is going up. But if you buy them..you do have to understand...that the cost of using the right equipment to make them sound good is another problem. Plus the fact of the room size.

On top of that you do have to throw money at upgrades..so you have to take that all into account.

Not sure why you dislike the 1C's...MR B but..thats up to you.

westmassguy

I think any SDA from 3rd generation forward should be given serious consideration.

Big Dawg

I have, or have had, both 2Bs and SRS2s (which use the same drivers and configuration as the 1Bs with a larger passive radiator). Both can be upgraded to "TL," and both are excellent speakers. I'd go look at the ones for sale locally, and listen to them. If he likes them, he should buy them. Plus, he should understand that they can sound much better once modified.

Mr. Bubbles

naturallight wrote: »

Not sure why you dislike the 1C's...MR B but..thats up to you.

It's not that I don't like them; just like them the least of any SDA I have heard. If I had never heard any other SDA's I would probably like them fine. They do sound good compared to most other speakers, and have the SDA effect. I just started with the 2A's and expected an improvement when I "upgraded" to the 1C's. This (to my ears) was not the case. I sold the 1C's and then went to SRS's and then 1.2TL's and heard as well as bought and sold several others before getting another pair of 1C's just in case I misjudged before. Once again, I was simply dissapointed as compared to the others. Though I do like my SRS's and 1.2TL's, from a purely sound standpoint, I like the 2A's I own, and 2B's Ive heard, the best. From most listening I've done on the vast amount of gear involved over the years, I've come to terms with the fact that mt ears generally prefer simplicity. Simple 2 way systems with few drivers and few components in the source line tend to be to my liking. Electrically this ads less to the signal source and physically it allows less phase cancellations/ peaks, and fewer time alignment issues.

PolkieMan

Quite happy with my 1C's my 2.3Tls are better but not so much.

Schurkey

If my 1Bs could use the AI-1, I'd quit shopping for larger/newer. They sound fantastic...but I've got a pair of monoblock amps that are anxious to show-off, and the 1B won't let them.

heiney9

Mr. Bubbles wrote: »

It's not that I don't like them; just like them the least of any SDA I have heard. If I had never heard any other SDA's I would probably like them fine. They do sound good compared to most other speakers, and have the SDA effect. I just started with the 2A's and expected an improvement when I "upgraded" to the 1C's. This (to my ears) was not the case. I sold the 1C's and then went to SRS's and then 1.2TL's and heard as well as bought and sold several others before getting another pair of 1C's just in case I misjudged before. Once again, I was simply dissapointed as compared to the others. Though I do like my SRS's and 1.2TL's, from a purely sound standpoint, I like the 2A's I own, and 2B's Ive heard, the best. From most listening I've done on the vast amount of gear involved over the years, I've come to terms with the fact that mt ears generally prefer simplicity. Simple 2 way systems with few drivers and few components in the source line tend to be to my liking. Electrically this ads less to the signal source and physically it allows less phase cancellations/ peaks, and fewer time alignment issues.

2A's are far from simple since the tweeter also is part of the SDA circuit. From a sound output stand point the 1C's are simpler and more natural, less phasey, less peaks so it seems your analysis of what you think you like might be flawed.

It's ok to like one model over the other, I FAR prefer the 1C's to any of the earlier gens for the above reasons. I only point it out because what you say you like the 2A's for is not what they are best at. So perhaps it's other reasons.

H9

Mr. Bubbles

H-9

you may be correct on some of your points as I have never actually measured any of the SDA's I have owned or heard. However the 2A's tweeters are connected no more to the SDA circuit than the tweets in the 1C's. I think but am not 100% sure that none of the models have the tweets tied to the SDA circuit except the very early models like the 2's, 1's/1A's, and early CRS's.

The 2A/B's as compared to the 1B/C's have only one high frequency source and effectively one mid/ mid-bass source (not accounting for the dimensional driver, of which they also only have one). These drivers all play a different part of the signal that comes from each cabinet. Again not counting for the minor overlap of the summed sound of the dimensional drivers. The 1B/C's have twice as many of each (though the tweets are operated as a progressive point source, they still have both tweets playing a major portion of the signal the same from each tweeter).

With the driver configurations in mind in the 2A/B's this creates the possibility of getting the three individual drivers in each cabinet the exact same distance from the listening ear on that side of the head incorrect a roughly 3 to one ratio. Also since the drivers in these models all essentially play a different signal, there is there is little to no room for nulls or peaks in the same signal, only time-alignment issues between the source points; say a given micro-second delay between the mid signal - tweeter signal - dimensional signal. Now with the driver configuration in the 1B/C's you get a roughly 6 to one ratio of probability for not getting all drivers exactly the same distance to the listening ear on that side of the head. Also due to the multiple drivers playing the same frequency bands ( 2 tweets, 2 mids, and 2 dimensional drivers) you get the possibility of phase shift in the signal of the same range and also get the possibility of slight peaks or nulls due to the very minor difference in reflections of the signal between the upper and lower drivers. These things make the possibilities of having a less smooth frequency response much much greater. This gets worse still as the models go up to the SRS's and 1.2's etc. These principals are a big part of the reasoning behind the progressive point source tweeters, the staggered tweeter mount on the RTA 12's, and designs like DCM's co-axially mounted drivers in their TF and TW series, as well as others.

Some may feel they cannot hear these anomalies enough to be concerned or get the speaker positioning exactly right, etc. My ears hear these things easily in most cases and from analyzing the physical properties of these functions, I know this is why I hear these things in many cases. However since time delay due to crossover design etc. als plays a role in exactly how we hear these anomalies, it is not strictly the number or placement of the drivers that control these things. For this reason you may be correct in saying the 1C's a smoother. Again, I have not measured them. I am only speaking from my experience listening to these speakers and my knowledge of physical properties. I only meant to explain that the possibility (not 100% set in stone) of getting a better sound leaned more towards the 2A/B's (again the simpler design) for these reasons.

Also you are correct in that this is not the only reasoning I have for likeing the 2A/B's better than the 1B/C's or even the SRS and 1.2TL's. I prefer the overall tonal balance as well which is due to other things like the characteristics of the actual drivers to a lesser extent and a balance of driver/ passive/ cabinet ratio to a greater extent. These things simply come down to my personal hearing curve and taste. For quick listening these would be the top reasons, but when I sit to enjoy myself and do some critical listening the other factors are what prevent listening fatigue as much as any other factor, for me.

Thank you H-9. I enjoy these discussions. They make me step back and re-analyze my thought process to verify and learn.

heiney9

You must have a transitional pair of 2A's as the early 2A's did have a dimensional tweeter. If yours have the single tweeter then I stand corrected.

The third paragraph of you post is incorrect as to how the SDA works in multiple driver SDA's. You can search for the proper explanation as I and others have posted about it before. I'm sorry, but I don't have the time or energy to rehash it all again for the umpteenth time.

H9

westmassguy

Heiney9, I believe you're referring to the SDA-2, which was 2nd generation, and had a stereo and dimensional tweeter, The 2A is 3rd generation, and has a single tweeter.

heiney9

There are 2A's that have side by side tweeters. But many 2A's are single tweets. If you have a copy of Darqueknights SDA Compendium you will clearly see 2A's with 2 tweets. Refer to pp 7-8 in the compendium. After 1986 (approx) the 2A's were upgraded to use a single tweet. Both models (single and double tweeter) are considered 3rd generation.

But thanks for trying to set the record straight

But you are correct most 2A's are single tweeter. I wrongly assumed Mr. Bubbles had 2 tweets. It's Polk and those damn transitional models

H9

westmassguy

heiney9 wrote: »

There are 2A's that have side by side tweeters. But many 2A's are single tweets. If you have a copy of Darqueknights SDA Compendium you will clearly see 2A's with 2 tweets. Refer to pp 7-8 in the compendium. After 1986 (approx) the 2A's were upgraded to use a single tweet. Both models (single and double tweeter) are considered 3rd generation.

But thanks for trying to set the record straight

But you are correct most 2A's are single tweeter. I wrongly assumed Mr. Bubbles had 2 tweets. It's Polk and those damn transitional models

H9

I don't have the SDA Compendium, just the Handbook