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req
04-29-2006, 06:21 PM
i have a pair of bose 901 cabinets from back in the eairly 70's that my dad wants to use, but all the surrounds in the cabinets (its a line array of 8 speakers on the back and 1 one the front) are totally thrashed and disentegrated.

here is a few shots -

http://i3.tinypic.com/ws9pfk.jpg

EVERY speaker is destroyed because of non-treated supfoam surrounds :'(
http://i3.tinypic.com/ws9pq9.jpg

and heres the crazy wiring diagram
http://i3.tinypic.com/ws9q4l.jpg

says on the bottom "for normal recievers use only "+" and "-" terminals, see owners manual for use of "*" terminal."

now, my DMM ran out of batteries and was a POS so i dont have one at the moment. it SAYS on the internet they have a nominal impedance of 8ohms, so im guessing its some crazy weird way? i dont know if each driver is 16, 8, or 4 ohms.

i also cant find ANY T\S params for the speakers. i want to REPLACE EVERY DRIVER with something like the NSB's that wereon PE for $0.50\each, because we all know boston wasnt the greatest equipment ever.

the MOUNTING DIAMATER for the speakers is exactally 4-1\4 inches and i can fit about 5" speakers at the biggest. i was looking at these;
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=290-370

but they are 4ohm each, and as you can see the diagram shows that the stock speakers are ALL ran in series, and the only config that i can see for anything near nominal impedance of 8ohms is all 1 ohm coils in series. :crap:

if i did all 4ohm coils, i wouldnt be able to hook up that front speaker, but i could get nominal of 8ohms, i would be able to run a set of 4 in series for 16ohms, and then the pair of 16ohm series arrays, in parallel for 8ohms.

how would i hook up that front speaker?

or better yet, can anyone find me some drivers that are manufacturered for CHEAP (im talking SUB $10\each and NOT a REFOAM kit?

thanks for the help - many minds are greater than one i always say :p:

springy101
04-29-2006, 06:32 PM
if there are 8 drivers then they should be 8 ohms each

# of voice coils x impedance of voice coils / # of drivers = ohm load
8 x 8 / 8 = 8 ohms in series

these should work i guess they are the same ones you linked to but 8 ohms

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=290-372

req
04-29-2006, 06:34 PM
there are NINE drivers if you read my thread.

8 on the back, one on the front.

http://www.the12volt.com/caraudio/boxcalcs.asp#ser

throw nine SVC 8 into the series calculator, tell me that its 8ohms.

springy101
04-29-2006, 06:36 PM
oh ok, i was wondering what that extra circle was. why the hell would they put an odd number of speakers in? and have no clue on how to get 9 drivers to 8 ohms.

hmm this is quite a conundrum

req
04-29-2006, 06:41 PM
:p:

thanks for puttin your brain to work. i dunno what im gonna do. maybe if i got a 4 channel reciever and hooked something up wierd i dunno le-sigh.

Prowler573
04-29-2006, 06:41 PM
The OEM drivers in that enclosure may have had a very non-standard inpedence that you won't be able to source in a commercially available replacement driver.

Additionally - you do not have to run all of whatever you put back in there in series, do you? I cannot see why you absolutely have to rewire it the way it used to be. Retrofitting isn't always putting things exactly back the way they were originally - things get changed to upgrade or enhance. :)

So - with that in mind - could you do SVC drivers for the back 8 and a DVC driver for the front? Yes, on the same power source the DVC driver would see a different level of wattage than the rest but I'm just looking for ideas here...

req
04-29-2006, 06:45 PM
well, i thought about that (see post before yours of mine)

and i could get a dvc 4 speaker or summin. the good part is each speaker has its own "enclosure" but the 8 speakers on the front are set up so that each set of 4" speakers use the same port. its some sort of weird T-Line-line array lol.

and the front speaker is like a normal ported enclosure with its own port and everything. so if the front speaker ended up having its own weird volume then maybe thats what would have to happen.

Prowler573
04-29-2006, 06:49 PM
Bose speakers = Teh LOSE :mad:

My wife has a pair of 501s that her mum gave her. Still intact and play fine - but no high end extension to speak of. They'll make nice bookends, I think.

req
04-29-2006, 06:51 PM
lol, better than the television speakers, and he really liked them and spent a buttload of monies back in the day.

and nothing a tweeter and xover cant help lol :D

Prowler573
04-29-2006, 06:54 PM
lol, better than the television speakers, and he really liked them and spent a buttload of monies back in the day.

and nothing a tweeter and xover cant help lol :D

Yes, yes he did. :crap:

I reckon springy will and I will keep hunting around online but manoman ~ You've presented us with a bit of a challenge, fella!

req
04-29-2006, 07:04 PM
well thanks, ill keep my eyes open too :p:

stupid bose 901 shizt.

req
04-29-2006, 07:46 PM
cmon guys any idears?

ill do my best to get a DMM and find the resistance on those coils asap.

BassAce
04-29-2006, 09:18 PM
How about this:

http://www.partsexpress.com/webpage.cfm?&DID=7&WebPage_ID=3

My bad you said no refoam kit in big bold letters to catch attention in which I failed to look at. My bad.

Darth Audio
04-29-2006, 09:46 PM
I think MCM has replacement drivers, but unfortunately my catalog is at work and the search I did on their site was fruitless. (Their search engine sux!) If you do not have a solution by Mon. I will look it up in my catalog for you.

req
04-29-2006, 10:03 PM
i would really appriciate that, and if you can get me a price on each driver that would be sweet.

thanks mang.

thylantyr
04-30-2006, 02:23 PM
that my dad wants to use

The money invested to rebuild this could be used to make something superior.

req
04-30-2006, 02:26 PM
well please elaborate, because replacing all the drivers with the said goldwood speakers would cost just bout $100.

so my budget is btweet $100 and $150. for all materials. and i am terrible at designing things like this.

so please, please show me soemthing that will get quite loud and sound really nice. its going to be a poker room, and he does not want something crazy obtrousive sitting in the middle of the floor. he is not a sound quality freak, he just wanted his vintage speakers to work.

so please thy, fill me in with a design and the hardware needed for this project and ill build something for sure.

DBfan187
04-30-2006, 02:27 PM
i have a pair of bose 901 cabinets from back in the eairly 70's that my dad wants to use, but all the surrounds in the cabinets (its a line array of 8 speakers on the back and 1 one the front) are totally thrashed and disentegrated.

here is a few shots -

http://i3.tinypic.com/ws9pfk.jpg

EVERY speaker is destroyed because of non-treated supfoam surrounds :'(
http://i3.tinypic.com/ws9pq9.jpg

and heres the crazy wiring diagram
http://i3.tinypic.com/ws9q4l.jpg

says on the bottom "for normal recievers use only "+" and "-" terminals, see owners manual for use of "*" terminal."

now, my DMM ran out of batteries and was a POS so i dont have one at the moment. it SAYS on the internet they have a nominal impedance of 8ohms, so im guessing its some crazy weird way? i dont know if each driver is 16, 8, or 4 ohms.

i also cant find ANY T\S params for the speakers. i want to REPLACE EVERY DRIVER with something like the NSB's that wereon PE for $0.50\each, because we all know boston wasnt the greatest equipment ever.

the MOUNTING DIAMATER for the speakers is exactally 4-1\4 inches and i can fit about 5" speakers at the biggest. i was looking at these;
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=290-370

but they are 4ohm each, and as you can see the diagram shows that the stock speakers are ALL ran in series, and the only config that i can see for anything near nominal impedance of 8ohms is all 1 ohm coils in series. :crap:

if i did all 4ohm coils, i wouldnt be able to hook up that front speaker, but i could get nominal of 8ohms, i would be able to run a set of 4 in series for 16ohms, and then the pair of 16ohm series arrays, in parallel for 8ohms.

how would i hook up that front speaker?

or better yet, can anyone find me some drivers that are manufacturered for CHEAP (im talking SUB $10\each and NOT a REFOAM kit?

thanks for the help - many minds are greater than one i always say :p:lol my dad has the same ones along with the 301s. Same **** thing happened to his too! lol

DBfan187
04-30-2006, 02:31 PM
http://cgi.ebay.com/Bose-901-LIFETIME-Speaker-Repair-Cloth-Kit-P-L901K_W0QQitemZ9719616132QQcategoryZ61374QQrdZ1QQc mdZViewItem

Shelbyturbo1989
04-30-2006, 07:21 PM
My friend's dad built a set of those when the series 2 were out. The drivers in his cabinets are 8 ohms. There are three drivers in parrallel which gives 2.66 ohms:

(1/( (1/8) + (1/8) + (1/8) )) = 2.66

then there are three sets of these in series which brings the impedence up to 8 ohms

2.66 + 2.66 +2.66 = 8

That's how you have nine 8 ohm drivers and still maintain an 8 ohm speaker.

Vic

req
04-30-2006, 07:34 PM
can anyone find me some drivers that are manufacturered for CHEAP (im talking SUB $10\each and NOT a REFOAM kit?


http://cgi.ebay.com/Bose-901-LIFETIME-Speaker-Repair-Cloth-Kit-P-L901K_W0QQitemZ9719616132QQcategoryZ61374QQrdZ1QQc mdZViewItem

sigh.

thanks for the info about 3 sets together for 2.66 ohms each and then up to ~9

i think thats how im gonna have to do it.

http://i2.tinypic.com/wv1f6v.gif

DBfan187
04-30-2006, 09:43 PM
it says, RE-CLOTH, not RE-FOAM!

;)

req
04-30-2006, 10:40 PM
lawl u noob :D

thylantyr
04-30-2006, 11:19 PM
I don't follow the bang for buck loudspeaker crowd. I did get side tracked last
year to build the budget line array using the now sold out 49 cent drivers.
That would be a great project for you. Seek low cost drivers and just make
a tall azz array with center tweeter, it will perform better that fixing the Bose.
To extract more bass from weak drivers, port the array and tune it with a peak.
Black sheep, but works miracles.

req
05-01-2006, 12:06 AM
i didnt say it had to be a sweet audiophiole bass thing.

this is for my dad. he does not want to spend lots of monies.

and he wants his old speakers that he got nigh on 30 years ago.

i dont follow your non-understanding for the crowd that is not audiophioles that. 100~150 is the absolute budget. i dont want to do alot of work.

i dont care if there is not a ton of bass or the speakers arent the best.

these cabinets are here, and somewhat cheap to fix. im just gonna replace with those goldwoods. *sigh*

Darth Audio
05-01-2006, 09:10 AM
The Bose replacements that MCM has are for some Bose stage monitor and are a different size then what you are needing. Which Goldwoods are you guys talking about?

IamDeMan
05-01-2006, 09:22 AM
Bose speakers = Teh LOSE :mad:

My wife has a pair of 501s that her mum gave her. Still intact and play fine - but no high end extension to speak of. They'll make nice bookends, I think.I will agree to their overratedness of product they currently haveout, but I like the sound of the 901s. My dad had a set too and I always thought they gave a nice sound. They filled out a room nicely.

req
05-01-2006, 12:23 PM
The Bose replacements that MCM has are for some Bose stage monitor and are a different size then what you are needing. Which Goldwoods are you guys talking about?

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=290-372

Darth Audio
05-01-2006, 12:53 PM
Well I guess those will work since your dad isn't too concerned about hifi sound. Actually some of the Goldwoods aren't bad. I used some of their 6.5 aluminum mids and those little $5 Dayton tweets w/ a crossover I designed for a friends car. He's a cheap bastard if you hadn't gathered that, but anyway it sounds pretty good. They aren't the most efficient drivers though, I had to use like a 5db L-pad on the tweet. Let me know how it turns out w/ the 901's.

BTW I checked out your IB install, very nice. I had some OLD MTX Terminators in my old Cutlass in a IB config. Man they would drop and were very clean.

joetama
05-01-2006, 02:03 PM
I would tell your dad sorry about your loss, and go build/buy something new. Cause well, TV speakers might just sound better. Just my 2 cents.

req
05-01-2006, 02:24 PM
lol b&w


i still have not been directed to anything within that budget (up to 150) that i could build. and until that happens, im just plannin on swappin out the drivers.

you keep saying "build something new \ buy someting new" but i dont know a **** thing about ht stuff, and we still dont even have an amp for them.

so point me in the right direction with a cutsheet and driver\xover list and ill be set to go. until then, im planning on swapping the bose.

joetama
05-01-2006, 02:27 PM
Hold, on don't get your ******* all bunched up. Give me a little bit I'm a busy man, and I'll point you in the right direction....

$150 to sound better than BLOWS, I'm sure I can come up with SOMETHING.....

joetama
05-01-2006, 02:29 PM
Can you manage to build a X-Over or do you want something pre-made??? Cause that factors inski.....

req
05-03-2006, 01:28 AM
i can build pretty much anything, im just upset because its so hard to find some budget speakers with plans :sigh:



i was jsut kinda having a bad day - so dont take it personally :p:

anywho, i can solder i can fiberglass, i can make nice boxes, yea yea. :D

but yea man, hit me up on aim LREQL if you wanna talk about it.

Darth Audio
05-03-2006, 10:00 AM
Look at some of these Req they will all come in at or under your budget.

http://www.speakerbuilder.net/web_files/Projects/DBP/dbp.htm

http://www.zaphaudio.com/audio-speaker13.html

http://www.speakerbuilder.net/web_files/Projects/peecreek/pcrkmain.htm

Also have you considered the BR-1 kit from parts express? Not very exciting but quick and easy!

req
05-03-2006, 10:07 AM
the problems im having so far, is that the boxes and drivers would fall in the range of under 150, but once you get done with the crossovers, your well over $200.

the crossovers in most of the projects listed above are easily $60+ for all the parts *sigh*

and we still do NOT have an amplifier for the project, so spending that much is kinda useless...

Darth Audio
05-03-2006, 12:10 PM
The first project is only $100 w/o enclosures but I'm sure you could whip out a decent set of enclosures for less than $20-30. The BR-1 is $139 for everything.

Also I'm working on a set of speakers for my office that are def. elcheapo. I'll let you know how they turn out and maybe you could build a set of those. Downside, they will have to have a sub w/ them.