Doug G.

Check to be sure the surrounds are intact all the way around and that the cabinet is sealed. With everything together, carefully push the woofer cone in and it should return fairly slowly, not immediately. Be sure it's not something other than the speakers, too. Can you hear anything, at all, from the woofers? Also, just because the crossovers look OK, it doesn't mean they are. The components need to be checked. Doug

There are blanks, first, for the pictures for me but then they all appear below that. I didn't know or had forgotten they made brown Mortite (mine is gray and is still pliable in the box after 16 years). I guess it make sense. I've even just used a single rope around the woofer but two is probably better. I have even rerolled it after removing a woofer and reinstalling. My 1970 pair is awaiting grille cloth installation and i want to do it with staples. I bought them from a guy who moved to Rochester, MN from out east. He said his parents lived right down the street from Advent's original location and may have purchased them right from the factory. BTW, I always like it when I check in here and see topics in bold on the left. Doug

Thanks! Doug

Yes, I don't know. It appears to be a very neat job on the driver in your picture and, being it's working well. maybe just leave it. It would be different if you could hear a difference between the other advent woofers. I should add that the two I redid with the correct surrounds were not done too well with the surrounds even coming loose in some spots and the outer flange kind of wrinkled. Doug

That material actually looks good. I can see very minor differences in thread thickness but that's really only apparent to someone who knows exactly what the original cloth looks like and is OCD about it. How did you attach the grille cloth? I still haven't installed the cloth I got a while ago and I'd rather do it as it was originally done but I have only found one source for 1/8" leg staples and I don't know if they are heavy duty enough to be driven into Masonite. So, I may just use contact cement but I have been hedging. Doug

Yes, it is the wrong surround. It appears to be the surround made for the Masonite woofer with a wider outer flange. Also, the inner flange of the surround belongs under the cone edge, not in front of it. As to whether to replace it with the correct surround, it depends. If it appears to work correctly, no rubbing, etc. you can leave it. A bigger concern is if the surround material is compliant (floppy) or not. It looks kind of rubbery to me but that's kind of hard to tell from a photo. It should feel relatively soft when you poke the roll with a finger, not "bouncy". Now me, it would bug me and did. A few years ago, I bought a pair with those same surrounds and even though the drivers worked fine, I changed the surrounds just because they were incorrect. Doug

Yes, these days, the same surrounds are usually sold for both versions of the first Advents (original and New). Some vendors still sell separate ones, as you found, Kent. The only difference is the original surrounds for the original Advents have a wider outside flange where it fits behind the Masonite ring but the ones for the New Advents, with the narrower flange, work fine for the original Masonite woofers, too. The main things are that the compliance (floppiness) and roll size are correct. Doug

Usually, a problem will not present if the speakers are driven at reasonable levels which is why most manufacturers claim the ability of their amps to drive 4 ohm loads. It's just something to be aware of and I believe, if memory serves me (a danger, these days), Advents, whether original or New, dip down near two ohms in some spots on the impedance curve. Pete would know better than me. Doug

Norman, I don't know what you mean by a "metal adapter". The driver frame, in each case, just mounts right into the cutout in the speaker board. Both drivers use the same cone and the only real difference is a slightly greater excursion for the Masonite woofer. The Masonite ring was used to adapt a 10" cone to a 12"frame. While they were selling the original Advents, they developed the all metal frame to eliminate the Masonite ring. The surround fits right into the frame without the ring. Differences in sound between the two models will be due to the change in crossover frequency (1000 Hz. to 1500 Hz) and possibly, the relocation of the woofer to get it closer to the tweeter for better driver integration. Also, in the original Advent, the woofer inductor is always in-circuit whereas in the New Advent, it is switched out of circuit in the "extended" position. There is really no reason the two different woofers would sound any different used in the same speaker and I have found that to be so. There is also no reason the bass extension would be any different between the two speakers. The cabinet size is basically the same and they are both sealed. The position of the woofer on the speaker board doesn't matter. Doug

The thing to remember with solid state amplifiers is, no matter if they have main and remote terminals or not, the speakers are being driven from the same output transistors. There are not separate outputs for the main and remotes. There are merely switching schemes to turn one or both pairs on or off. If an amplifier is capable of driving 4 ohm loads, the switches will typically be wired so the speakers are in parallel with both on. If an amplifier is not designed to drive a 4 ohm load, the switches will be wired so the speakers are in series with both of them on. The way to check is to connect a pair of speakers to, say, the main terminals and turn them on. While they are playing, with nothing connected to the remote terminals, turn the switch for the remote speakers on. If the main speakers keep playing, the switches are wired in parallel. If the main speakers stop playing, the switches are wired in series. A pair of Advents dip pretty low in impedance at some frequencies and are much better driven by a separate amplifier for each pair, even though they are rated at 8 ohms. This is true of most setups. In spite of what manufacturers advertise, a 4 ohm load stresses an amplifier quite a bit more than an 8 ohm load. More current flowing through the output devices produces more heat which, of course, is the enemy of longevity. I have four Advent stacks in my quad system and each pair is driven by its own stereo amplifier - four stereo amplifiers or, in my case right now, two quad amplifiers. Doug

I don't know the answer and I know I have read those pages before but, for some reason, I didn't notice certain things. I read them again, now and: It's the first time I noticed Advent called out Mortite by name as the sealant they used. They were pretty vociferous about NOT soldering any wire splice connections (they used wire nuts in the early ones). Also: The service bulletin is an early document from 1970. I assume the others are too, based on them referring to Mortite under the tweeter and hand corrected. This is service bulletin 3. I wonder what the other service bulletins were/are. (OK, I'm going to look in the "Index of Advent" files - nothing there). The earliest Advents used Mortite under the tweeter plate which was quickly replaced by the foam gasket, if it is assumed the hand-written corrections were done contemporaneously. Advent recommended rotating the woofer a bit, if it is removed, and using new holes to remount it out of fear of stripping the original mounting holes. I would rather just be careful. Doug

I have one pair like that right now, too. They are very early ones from 1970 I bought from a guy originally from out east and his parents lived right down the street from Advent in the original location. He said they may have bought them right at the factory but wasn't sure. Unfortunately, none of the drivers in them are original right now. Either his parents or he had them reconed with 12" plastic cones. They probably just needed refoaming but most people, years ago, weren't aware you could do that and just had a complete recone done. Actually the frames are original and I have them in case I ever run across some genuine Advent cone assemblies. The tweeters, which I also still have are the early ones with no grille/cage on them and one of the leads broke right where it goes into the dome edge. So for now, they have Advent all-metal woofers and newer Advent tweeters in them. One thing, if you use the all metal woofers, use a thicker gasket or Mortite (like on the Masonite woofers) to seal them as the original thin gaskets may not seal well enough. You don't of course,want any air leaks. So, you can be assured that no matter which drivers you use, as long as they were made for the original Advents, they will sound the same, regardless. Doug

You can try spraying it into where the lever enters the switch body. It may work its way in there. Sometimes with toggle switches, if you push the lever toward the switch with it perpendicular to the switch, there will be some play/space created and the liquid will have a larger opening to enter. Doug

Yes, those look very nice. There won't be any perceptible difference in sound between the two woofers. After Advent stopped producing the Masonite woofers, they supplied the all-metal woofers as replacements. As far as what to do with what woofers, are the Masonite woofers in the vinyl cabinets original to them. If so, I would have a hard time removing one to put into the walnut cabinet but that's just me. Instead, I would get one off eBay and install into the cabinet with the all-metal woofer. If the Masonites are not original to the vinyls, then I wouldn't have a problem swapping them around and if such silly things don't bother you, go ahead either way. Like I said, no difference in sound. The installation method for the surrounds is different but they use the same ones, these days. Originally, the Masonite woofer surround had a wider outer flange but the ones made for the all-metal woofer with 1/8" flange work fine. Masonite woofer - outer flange behind the Masonite ring - inner flange, in front of the cone edge. All-metal woofer - Outer flange mounted on the little ledge on the frame - inner flange behind the cone edge. Good luck, those look beautiful. Doug

Somebody must have added the lacquer or varnish as they would originally just have been oil rubbed. I have a feeling lots of Advents ended up being redone over the years. I have one pair like that but they did a good job and they still look like they are oil rubbed so I left them. Doug

See this thread for the fabric to get: https://audiokarma.org/forums/index.php?threads/large-advent-cloth-pics-of-new-cloth-and-original-cloth.878255/ It's what I bought and it's so close to the original, you can't really tell the difference. As far as fiberglass or foam blocks, I would restore them to whatever was originally in them. The foam blocks didn't start until about 1975. I have pairs with both in them and soundwise, there really isn't any difference. There really isn't much difference between the 16,16 and 16,8 capacitor combinations, either. Doug

I have five pairs of original Advents, checked the caps in all of them as I bought them, they were all in spec, and my speakers all sound terrific. I mean, there is no harm in replacing them as a precaution and they are inexpensive, but I just don't think it's necessary. With my long history in electronics, unless electrolytics have leaked or have popped out the sealed end, they are usually OK. The ones in your picture look great. I know there are those who disagree, but that's my experience. Doug

They look original to me. What brand are they? Do the solder connections look real clean and like they have never been disturbed? Also, just because they are original doesn't necessarily mean they need to be replaced. Capacitor replacement has become an obsession Doug

If ANY Advent is lacking in bass, there IS something wrong with the woofers, themselves, or there are leaks in the cabinet, period. In fact, air leaks in any acoustic suspension speaker will completely ruin the entire frequency response. Doug

This thread is yet another reminder that, if you buy old speakers, you MUST be sure they have been restored to new condition before passing judgment. You can't buy a 30 - 40 year old pair of speakers and assume they are in listenable condition, no matter what a seller might claim. Things deteriorate with age. Doug

If the two 8uF caps are connected together, each end to each end (in parallel), that equals 16uF so either Advent did that or whoever did work on them later, most likely the latter. The only real reason to get another Masonite woofer and another "cageless" tweeter is for originality and so the two speakers are the same. Soundwise, it won't matter. That being said, it would bug me they aren't the same. In fact, it bugged me on one of my pairs that, when they were refoamed, in the past, whoever did it put different diameters of dust caps on the woofers so I had to match them up. It still bugs me a little bit that they are too large a diameter for original Advent woofers but I had to cover up the old glue line. Of course that they are porous caps results in no change to the sound. The Masonite woofers had the surrounds installed inverted (roll poking away from you) to avoid any possible interference between the roll and inner edge of the Masonite ring when the cone moves in and out. The all-metal woofer doesn't have that possibility, of course. Again, soundwise, it makes no difference. Doug

The tweeters originally had virtually no protection from being pushed in. In the first attempt to alleviate the field issues, Advent placed a window screen type grille directly into the tweeter opening in the Masonite grille frame. Then, they mounted an extra block with Velcro right under the tweeter to keep the grille, itself, from being pushed in. Finally, they put the cage type grille right on the Masonite frame of the tweeter. This proved to be effective although Advents still show up with the cage type grille pushed into the tweeter dome. This all happened in a relatively short period of time and by the end of 1971 or early 1972, they had the cage type grille on the tweeters. Advent even offered the grilles, free of charge, to owners of earlier speakers, to mount them themselves if they wanted. The crossover was changed, more as an effort to ease the tweeter from having to reproduce the lowest frequencies of its range as there were problems with owners blowing them in the field, too. Also, it was to make the integration of the woofer and tweeter smoother at the crossover point. A 16uF-16uF combination was first used for the two electrolytic capacitors and that was changed to a 16uF - 8uf combination in 1975. The resistor was changed and the inductors beefed up, too. The best place to see the differences is Pete Basel's site, here: http://baselaudiolabs.googlepages.com/ADVENT_LA_XO.html Doug

Hi Patrick, Those are early Advents with those serial numbers and before Advent standardized the "A" suffix. They would have come with Masonite woofers and tweeters like the one on the left speaker, without and grille/cage on the front. The left tweeter and right woofer are probably original and the left woofer and right tweeter, replacements. As to what to do with them, if you want to be absolutely original, you would want to get a tweeter without the grille for the right speaker and Masonite woofer for the left speaker. Soundwise, it doesn't matter as the drivers were always made to sound the same, regardless of iteration. I have a pair of very early ones also and they both have Masonite woofers but the woofers are not original. I have the original woofers but the previous owner had replaced the original cones with plastic cones so I am waiting to find original type cones to rebuild the original woofers. Whether I ever actually do it is a separate issue. I have the original "cageless" tweeters, too, but one of them has a broken lead right where it goes into the voice coil by the edge of the dome. So, they both currently have later tweeters with grilles/cages. I don't let it bother me too much. More important to have them operational. So, as far as how they sound, as long as you have real Advent drivers in them, they'll be OK. As far as the crossovers are concerned, the only way to tell is to see them and test the capacitors and verify that the resistors and inductors are OK. I am of the opinion that even capacitors don't automatically need to be replaced if they check out OK. Others replace them just because of age. That's your decision. If you do replace them, I would just use modern equivalent non-polarized electrolytics. Good luck. Doug

As I stated on AK, the only discrepancy is the serial numbers and driver dates. The drivers are definitely later ones as the tweeters have the black tape only going part way across the Masonite and the stamped dates, of course. Earlier (pre 1975) ones have the tape going all the way across. So either somebody stuck newer drivers in older cabinets or the paperwork was missing and they found older examples to stick on there. Who knows? Also, as I said, the tweeter cone colors make no difference as long as the magnets are the same size. Another thing I just noticed - the glue holding the Masonite ring on on the one woofer is dark. Is it reddish? The usual was a light tan, mastic type glue. I have seen other examples with the red clue, however. Doug

They look well-made and have gotten great customer reviews on Amazon. Doug