So I disected my old bose today

[digital desire]

I dunno, I was bored, and keep reading about building some new speakers. The problem I have is that for some strange reason, I still like the sound and imaging of my old bose 10.2 speakers. They are now 20 years old, and still on their origonal foam. I never liked bose products personally, except for this one set of speakers they have, 10.2, orginal series. They weigh 62 lbs a pop, (Does bose make anything that weighs half as much these days?) and have a unique arrangement. Two 8" woofers in a sort of TL alignment where they vent out the side, and two tweeters that point left and right from the front. One of the tweeters shuts off over 5K hz.
But in order to tip me into the building mode, just for giggles, I popped off one of the woofers to take a look at what they might have used for a network. I am no crossover engineer, but I have to think, they did not spend a hella lot of time on these. Iwould have thought $1200 speakers would at least have some sort of network for the woofers. Nope. Full tilt on those, wired directly to the terminal cup with no network,. The tweeters have a car dome lamp in series as a current limiter, and the inductors are wound with (I am guessing here) maybe 28 or 30 gauge wire. It made me laugh slightly as I just finished building the crossovers for these:
http://users.d-web.com/dbrown/db616tl2/db616tl2.htm
for my brother in law.
Anyway, here is a pic of the bose with its dress up.
This is not btw, a major bash on bose, (that happens enough else where) even though it might appear that way. I am just trying to sort out something, namely if I want to build a new set of speakers.
I really have the hots for the raw acoustics HT8's. My neighbor says: "How much of an improvement will I have over these?"
That is the question, because I still like the way these sound, yet I know there must be better out there. These have an imaging that I have not heard in other speakers. Will the HT8's blow the doors off these?
Feeding them with my adcom 555 mkII has helped the sound also.

Anyway, I hope there was a point to this post!

[digital desire]

Oh yeah, forgot to mention, they used those special caps that are rated for DC! (I did not notice polarity markings, but for instance, the first cap is 2.2uf 100vdc!

[Timn8ter]

There are many manufacturers that use electrolytics (even so-called "high end" brands) so that's not surprising. The inductors are interesting. They look like they're definitely geared for assembly line production.

When you built the MTMs did you notice a difference in the soundstaging and imaging compared to the Bose?

Do you like the way the DIY speakers sound?

If you enjoy the diffuse soundstage of the direct-reflecting design then maybe a standard monopole design is not for you. One option may be a bipole design.
Personally, if I were choosing between the Bose and the HT8, I'd take the HT8.

[digital desire]

The speakers my brother in law built (he does wood, I do solder) are the older 2 way design.
They have a more laid back sound to them, and the imaging did not strike me, but the do sound pretty good. They do not seem to have as much output as my speakers. (May be his decidedly low end reciever from best buy also). I am not able to do an A/B comparo, they are not in the same house.
Raw also has an apex kit for a few hundred more. It features a driver out the back to open up staging, and I am also considering that. I just missed a bomber one day sale. The apex (apex II actually) would make for quite a bit more work as a machined baffle board is not included in that one. That is a serious amount of holes to get perfect!
http://www.rawacoustics.com/CMS__Ape...formation.html
Thanks. I just need convincing, thats all!
One very real problem is not being able to hear before I build. I don't have a patient enough wife to do it multiple times.
I have a 12" tcsounds 2000 on the way to go into a 3ft cabinet powered by a buttkicker. That should probably influence my decision also.

[Timn8ter]

Nor can I comment on your brother's speakers. In general, if you're looking to build something with the Adire drivers you'll get the best results with a stout amp. Many of the older 2 channel amps had nice hefty power supplies that can do a nice job. Driving them with the $200 A/V receiver from the big box store would be a waste.
The Apex is a mammoth speaker. I know Dan and Al put a lot of effort into it and the results are impressive.
The WR125S and Extremis are not drivers I would call forward compared to some that have mid-range peaks. They tend to be very flat through the upper bass and mid range giving some the impression they are "warm" or "laid back". Putting them in an MTM arrangement can bring the soundstage forward a bit more however IMHO.

[69stingray]

Driving them with the $200 A/V receiver from the big box store would be a waste.

Timn8ter- why do you say this? I know the Adire drivers have a tendency to have low efficiencies, is that why?

digital desire- I am glad you liked your Bose. The crossover is designed for a manufacturing line, you can tell. I think you would be surprised by the crossovers in a lot of mass-produced speakers (not just Bose).

I am surprised by the full-ranged woofer, interesting. I wonder if the enclsoure it is it limits the higher-end naturally. I thought those woofers were in a 6th order bandpass type of enclsoure. Time to Google....

EDIT: Lower woofer is in a Bandpass type of enclsoure. Is the upper woofer full-range also??

[Salas]

It looks like they have used voice coil winding gear to make the inductors. The RDC must be high.

[digital desire]

Funny you say voice coil, I think that is *exactly* what they are, they look identical. Very thin gauge wire!
I think they are fairly rare (as bose goes) speakers. They made them only for a couple years and then went to lower mass products. The 10.2 series II that came out after these weigh 1/2 as much.
Here is a pic, not sure what the above pic in the band pass is, maybe the series II?
These appear to be transmision line towers. There is a baffle that runs the length of the cabinet and then vents through (maybe it is a band pass?) to a second chamber that vents out the slot that runs the length of the cabinet.

[Salas]

Those guys knew how to make pleasant sounding speakers with low manufacturing cost. Their ideas and models are so many. To be commercially successful to the general public is a respectable achievement.

[digital desire]

I have to agree. These speakers have kept me happy for some time. But come foam time, I think I may want to build something else. And that foam is approaching TBO.
Maybe I should title the thread diferently to "What would you build for this room?" :^)
You can see the sub cabinet against the right wall, mains get powered through a 325/per channel (4 ohm) adcom 555 mkII.
The sub is a tc sounds 12" 2000 with butt kicker and bassis.
Older sony es30 reciever. Room is about 14X22 X 8.
The Apex is probably over kill. but my budget would allow for it.
I like to turn it up once in a while...