SDA-1c side panels- do I need 'em + upgrade only one set of tweeters?

robosdad

Hello! Just picked up some a set of SDA-1c's and am currently waiting for the glue to cure on my (now corrected) shifted magnets. The other issues are a lack of connection cable (made my own with 16 gauge speaker wire + pin connectors/RCA connectors) and a bad SL2000 tweeter (used my leftover one when I upgraded the tweeters in my Monitor 10's). Now I have two questions left:

1. The side panels came unglued at some point. I have them (all four of them), but am not sure if I should necessarily glue them back on. Are they more or less aesthetic? Or do they serve a sonic purpose? And can you tell my cats to leave them alone?
2. I have a set of RD-0194-1 tweeters that I put in my Monitor 10's (they are my classroom speakers). Should I put them in my SDA-1c's? If so, would it be best to replace the top one on each side or the bottom one?

Thanks! Excited to be hear in Polkville!

msg

1. Yes, put the side panels back on, even if just out of principle for preserving original design.

1a. Get rid of the cats.

Jazzhead

Cats... we had two 20-pounders. Get one of these and they'll ignore everything else:

https://www.purrfectpost.com/

robosdad

Thanks for the tips, though getting rid of the cats would turn my whole family off of this strange vintage audio hobby I've found myself obsessed with lately... Since the cats are non-negotiable I'm still undecided on the panels- though I'm guessing that the panels are unnecessary acoustically based on the comments...

As for the other question, I'll ask that one again (maybe should have asked it separately). If you have a pair of SDA 1c's with all SL200's, and are sitting on two RD-0194-1's, how would you use them? Replace the upper tweeters? The lower ones? Neither?

Thanks!

pitdogg2

They're progressive source tweeter configuration, replace the loudest tweeter with the RD0194. You should really buy another pair of the RD0194 and make them all the same. The SL2000 to my ears are unbearable to listen to.

bcwsrt

Leave the 10s alone and get four more 194s?

Emlyn

Anything attached to the speaker cabinets is going to have some effect on the sound a speaker produces because the cabinets on most speakers vibrate in a controlled way when producing sound. It may or may not be audible in this case but not having the side panels does change the design. It just takes glue and some pressure over a little bit of time to reattach the panels for another 20 years.

Polk also made what they called "Studio" versions of the 1C model with a chipboard plinth on the bottom and no add on panels.

robosdad

@pitdogg2 @bcwsrt I'll need to wait a while before I can $$ another couple of 194's but if I like the SDA 1c's I imagine I will once the coffers fill up. The glue will have cured for my third shifted magnet repair job this afternoon, which means I'll finally be able to hear both speakers when I get home from work. : )

In the meantime I'll probably take pitdogg's advice and try to figure out which tweeters are the loudest and replace them with the 194's (and eventually replace the other two). My Monitors are in my classroom with terrible room acoustics, constant fan noise (two dehumidifiers) so I can't really appreciate any difference in sl2000 vs 194 there...

Schurkey

Upper tweeters should be "loudest".

Lower tweeter should be more frequency-restricted. The SL2000 were said to have a resonance/peak at ~12,000 to 13,000 Hz; but since the lower tweeter is rolled-off in the extreme treble it should be less-noticeable.

robosdad

For those that were waiting in suspense, my SDA 1's now have two 194's each, and the side grills are attached with velcro tape (in case they just prove too problematic with the kitties). Upon putting them on though, I saw that I only have three of the four side grills. Rats! Original owner has no idea where the fourth is.