How does SDA 1A stack up against 1B?

Middle Age

It looks like the sda imaging would be better with the side by side tweeters yet I have seen some members say you want the vertically oriented tweeters. I'm looking at purchasing one or the other. I can get either for about 700 shipped to me. If anyone knows of a better deal out there let me know.

Schurkey

The side-by-side tweeters are an older generation of SDA evolution. The SDA tweeter was dropped in favor of one or more non-SDA tweeters; if more than one the additional tweeters are frequency-limited to provide a progressive point-source.

Some folks are so annoyed by the SDA tweeter that they unplug it, rendering it silent.

1. Go for the latest-generation SDA that you can find/afford.

2. $700 seems high for 1A/1B; I assume that shipping cost is approximately 50% of the total--or--they've been COMPETENTLY upgraded with fresh crossover parts and other mods/updates.

Middle Age

If the 1bs don't use SDA on the tweeter thats a pretty big difference in the speakers. I would love to hear the two. I think I would love the directional sound from the tweeter as well. I remember the first polks I listened to in the 80's. 4 horizontal tweets and about 6 or 8 drivers. Sounded like one was in my left ear and the other in my right ear.

Middle Age

I'm looking at the manuals and can't acually find a model with 4 horizontal tweets. Thats the way I remember it, of course that was at a consumer electronics show over 25 years ago.

heiney9

Middle Age wrote: »

I think I would love the directional sound from the tweeter as well. I remember the first polks I listened to in the 80's. 4 horizontal tweets and about 6 or 8 drivers. Sounded like one was in my left ear and the other in my right ear.

They sound phasey and disconnected and very unnatural at times because there is too much dimensional information. Do yourself a favor and forget about the early SDA's. If it was so wonderful they never would have tweaked them to discontinue the use of the dimensional tweeter. The progressive point source is a better more natural configuration.

H9

heiney9

Middle Age wrote: »

I'm looking at the manuals and can't acually find a model with 4 horizontal tweets. Thats the way I remember it, of course that was at a consumer electronics show over 25 years ago.

SDA SRS
SDA SRS 1.2
SDA SRS 2.3
SDA SRS 1.2TL
SDA SRS 2.3TL

All are atleast 2 generations away from the side by side type SDA's, with the "TL" series being the best and last of the SDA's before they stopped making them.

F1nut

^What he said^

Middle Age

Thanks everyone, I'm starting to get a feel for the ones that would satisfy my SDA craving, compact, 1c, 3.1tl in that order. I dusted off my old Hafler DH-500 last night and I think it will have enough power though I'm not sure about the common ground. Time to do more research.

Toolfan66

This thread is so d?j? vu of a thread about a year or so ago...



Good luck!!

halo71

heiney9 wrote: »

Do yourself a favor and forget about the early SDA's. If it was so wonderful they never would have tweaked them to discontinue the use of the dimensional tweeter.
H9

Awww damn, wish I hadn't read that. :eek: Now I am worried a bit. lol

inspiredsports

Middle Age wrote: »

It looks like the sda imaging would be better with the side by side tweeters yet I have seen some members say you want the vertically oriented tweeters. I'm looking at purchasing one or the other. I can get either for about 700 shipped to me. If anyone knows of a better deal out there let me know.

Those prices are way high. I personally would stay away from the 1A's because of the tweeter architecture, but if you can get the 1B's cheaply enough (let's say $200-250ish) don't rule them out. A little known secret is the 1B (and nearly identical SDA SRS 2) crossover can be modded to drive RDO198-1's by simply replacing the 4.4 uf cap with a 5.8uf.

The low pass caps are big (and expensive) because of the 4-ohm MW6509 midwoofers, but modded this way the 1B is a sleeper.

Schurkey

inspiredsports wrote: »

The low pass caps are big (and expensive) because of the 4-ohm MW6509 midwoofers, but modded this way the 1B is a sleeper.

Not THAT expensive, ERSE sells a set of four 91uF (to make two pair of 182uF assemblies, one for each speaker) for $91. Those went into my 1Bs. VERY satisfied.

Of course, you can spend a whole lot more if you choose...

inspiredsports

Schurkey wrote: »

Not THAT expensive, ERSE sells a set of four 91uF (to make two pair of 182uF assemblies, one for each speaker) for $91. Those went into my 1Bs. VERY satisfied.

Of course, you can spend a whole lot more if you choose...

I meant by comparison to the one 20 uf/one 40 uf low pass architecture per cabinet with the newer MW6510/MW6503 and MW6511 equipped models. So newer models you are paying to upgrade a total of 60 uf

By comparison, the 1B (and 1986 SDA SRS 2) low pass uses two 34 uf, 1 55 uf and one 130 uf, so you are paying SIGNIFICANTLY more to upgrade 253uf of capacitance, over 400% more.

And yes, you are correct it is better to use 2 equal caps to get the 130 + 55 section covered. Don't get me wrong, modded 1B's, especially if you go with 198's, will run with the best.

From a modding standpoint (even if the 2 tweeter design sounded good and IMHO it doesn't) The 1A is an even worse proposition with something like 400uf of capacitance on the low pass board.

headrott

heiney9 wrote: »

SDA SRS
SDA SRS 1.2
SDA SRS 2.3
SDA SRS 1.2TL
SDA SRS 2.3TL

All are atleast 2 generations away from the side by side type SDA's, with the "TL" series being the best and last of the SDA's before they stopped making them.

Don't forget about the 3.1TL's. Lowly on the SDA SRS list? Yes, but they still put out some great audio.

Greg