hi everybody, i'm relatively new to these forums, but the site has been helping me for some time in my audio purchases as it's the first place i come for reviews before i choose to buy.

note: i'm sort of a newbie (that's more of a careful warning)

I was just on vacation and i picked up these two Analog & Digital Systems Inc. (ADS) speakers not knowing ANYTHING about them, because they were very VERY low priced, and after some close inspection they looked to be of good build quality with rubber surrounds and what i believed was a high-quality tweeter i only usually see on expensive tower speakers. Plus bothering to add fuse protection for the tweeter made me think they were at least worth a bit, so i tested them out with a cheap stereo and they sounded decent so i snapped them up. Low and behold i learned a bit during research and they are relatively high-end speakers (and VERY heavy), and sold for a decent amount on ebay. I dont know much about them though and i was hoping maybe someone could suggest proper placement and care so they will last as long for me as they have for whoever decided to get rid of them.

Here is a specific question about speaker care; In my bose 401's (in the pic on the left) I either neglected to notice when i bought them used, OR i myself damaged one of the tweeters and caused it to loose it's brightness. Basically I believe that would be considered as blown but since it still makes some sound i suspect the little voice coil is just about fried but still conducts so it still puts out a little. compared to the other channel speaker it's very muffled and almost not making any sound worth mention. (any thoughts or help on fixing that or finding a replacement tweeter is welcome)
Now that i have another chance at a nice pair of main front speakers, I don't want to ruin them, and i wanted to know how i should limit myself in experimentation with volumes and treble/bass adjustment so i don't ruin these rare and old speakers.

the tweeters in the L520's have fuses so do i have to worry about ruining them with excessive volume or trebble boost? i'm not experienced enough to know how "bright" they should sound and i don't want to crank the treble so much and/or crank them so loud that they fry.

also, how do i clean them? i lightly felt the surface with my fingertip (without pressure so as not to push the dome in, and on the edge of the driver, not the top) to see if it was a hard or sticky surface, and as some on here probably know it doesn't appear to be the easiest thing to clean because it seems soft. There is a bit of dust i'd like to remove but im not sure how.

well i guess that's all for now. if you guys want to comment on any of the speakers in that pic feel free. i'm trying to learn what is supposed to be considered good sound or even exceptional sound and how far away i am. with all the audiophiles out there it makes me wonder what it's like to experience sound perfection and without knowing someone with that already, it's hard to tell how close i've come. it's all relative i suppose, but yeah, what do you think? How would those Technics speakers compare to others? they seem decent but not that great, but i dont want to underestimate a good thing. my new ADS speakers seem to produce better bass and highs though, the only thing the Technics seem to do better is the mid frequencies but i've barely had a day to mess with the new speakers.

Speakers in pic;

left; bose 401 - first edition, not the 87 model
middle; ADS L520's - dusty, i just got them and haven't had a chance to clean them yet.
right; Technics SB-L50's - i think i've seen similar ones with a sony badge? not sure, its been awhile
bottom left; Ultimate sound ST-1212 sub.

thanks for looking! let me know if anyone wants any more info or pics. I'll post up my amp and speaker watt/ohm ratings in a minute.