Why upgrade SDA 1 to SDA 1A?

machone

Although I am new to this website I have owned a pair of SDA 1 since the early 80's. Until I visited this website a thought that I had a pair of SDA 1A because that is what the sticker on the back of the speaker enclosure indicates (see attached photo). As I disassembled a speaker last night I noticed that I have SL1000 tweeters and external tweeter fuses. I also noticed a mixture of drivers (3-MW6600X and 1-MW6501). I have attached a photo of the crossover for further identification.

I could not get the photos to attach? So I will try to describe the crossover.
The crossover is two round boards one is attached to the speaker post/fuse holder and the other is just above the fuse holder. Each board has one yellow cap (T1 E-0012-1 12J100V) and one brown cap (TS1-8348 USA PXA27NV5OF 27uF-50VAC AC)

I want to keep these speakers.
My plan is to recap/rebuild the crossovers and maybe a tweeter upgrade.
I am driving these with a Hafler 500 so impedance should not be an issue.

My questions are as follows:
1. Is this an SDA 1?
2. If it is an SDA1 then WHY should I upgrade to a SDA 1A? I have reviewed the instructions on this website but could not find a reason to upgrade.
3. Should I include upgrading the SL1000 to the RD0194-1 tweeter? I see a that there is a minor clearance issue that is easily resolved.

I tried to search for these answers so please forgive me if this have been discussed before.
Thanks

Faustin

This may help with identification. Pictures would be helpful.

http://www.gimpod.com/sda-id.html

machone

Thanks Faustin. Everything points to SDA 1. I guess the label on the back of the enclosure is wrong. I can't attach photos for some reason? Help!

PolkieMan

If your picture are too large they may not post keep them under 250K

machone

I used chrome and they post with no problem.
I am reading the conversion instructions:

1. I don't have a removable crossover panel.
2. I don't have a horizontal enclosure division.
3. I do SL1000 tweeters with external fuses.

What model do I have?

machone

I found the answer in this forum by pitdog2.

"wrong you have SDA1a. The difference are as follows SDA1 had ports for the top 2 MW and each had their own box. SDA1 had 3 inductors. SDA1a had no ports and the MW boxes removed SDA1a had 2 inductors and came with SL1000 and SL2000. Now here is where slight difference's came to play SL2000 SDA1a had the MW's lowered slightly to make room for the SL2000 tweeter The SDA1a with the SL1000 tweeter when you used a SL2000 or RDO-194 tweeter dome it is almost behind the top of the grill frame"

SDA 1A is my model.