I'm just sharing this for the curious. The gentleman that replied earlier that seemed a bit off supposedly worked at Bose back in the day and according to him, Advent/Jenson and I think he said JBL. He's 63 now, semi-retired and repairs speakers as a hobby. He just sent me this, I didn't ask him what position he held at the previous companies he worked for.
Right -- when I work over a speaker such as the BOSE 401's I used Everything from the old JBL's , so i drilled an Extra whole for the second tweeter ... they said it would Hurt your tweeter's because the parts for the cross over were designed for within 2 ohm --- they know their system and are not known for cheating on parts like Bose and all those poor quality speakers coming here now... We get our material from China so we have to adapt to their spec's--- I just change the cross-over's-- I have a Goodwill near me and they always had Advents ,so I stocked up cheap ... i knew someone working there --- But a Digital meter is the answer to check the ohm's from the wire in connector on back--- the cap's and resistor's work together --as I said most speaker companies lie --- even amps have a 4-8 ohm switch but that is for them to test---always use 8 ohm setting...little things they do not tell you ,you have to regulate yourself --- they are quite happy if things go wrong because people do not have an ohm meter... Those ADVENT-Laureat's are great , but I still put Acoustic Audio (kevlar) in the bottom for fun --- not a big difference -- it is all the cabinet and cross over..just got the rubber suurround in today to do the original Advent speaker's in --- remember foam is planned to wear out -- I still have 6 Bose speakers with the original cloth mix which will not wear out .... Why do speaker companies use foam ??? MONEY for repair people... Hey I KNOW microsoft screwed up that windows 10 upgrade last year on purpose ,,all kinds of trouble only to find out it was an inadequate upgrade ---OOPS!!! SORRY... I took it off on my Dell and stayed with 7 --- I started with Honeywell in 1978 and all we did to double the speed on a board was clip a wire on a chip--- always they plan ahead ...but the computer cost about 1 million then with 1 meg of memory-- my dell laptop has 4 and upgradable but that is what they want -- like the ohm's value --- very touchy .. Stay with what works, always check reviews on E-bay before you buy.. They still have HDMI problems on Amps even today on E-bay they try to sell the broken ones with no problem saying to you they are tested...