# denied by bose



## frustrated (Mar 21, 2011)

Puting together a system for the bedroom, was gonna rebuild a set of Bose 10.2's I've owned since 1993 for the fronts. Called Bose for the driver/crossover specs- AND THEY DON'T GIVE THOSE OUT!!! 10.2's have been discontinued since 1994, and Bose no longer repairs or stocks anything for them. I know about the trade-in option, but I love these teak cabinets! Anybody know ANYTHING about the crossovers or drivers in these?


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## drdoan (Aug 30, 2006)

Welcome to the Forum. No help with the Bose, sorry. Have fun. Dennis


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## frustrated (Mar 21, 2011)

Thanks, I know it's a longshot.


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## Mike P. (Apr 6, 2007)

> was gonna rebuild a set of Bose 10.2's


What exactly do they need?


​


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## Guest (Mar 21, 2011)

What needs to be rebuilt? Parts express has a speaker rebuild program. You could contact them if you need the driver surrounds redone. As far as the crossover, I'd hope the parts are labeled. If not, they might need to be measured for specs.


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## frustrated (Mar 21, 2011)

Wanted to change the xover fq's, installed 2 tang band 25-302sh from P.E. in each cabinet to replace the origs, but the 10.2's still sound restrained-lacking mid to high definition. Thought about looking for newer x's, but not knowing the specs on the orig drivers I am kinda stuck.


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## sickboy013 (Feb 28, 2009)

It'll be worse than pulling teeth to get that info out of Bose. This was an email that Bose sent one of the guys over on AVS.

*Bose does not publish frequency specifications. The reason for this is 
that we believe that such statistics do not add very much to an 
understanding of an audio product's acoustic characteristics and, even worse, 
can be misleading. Audio manufacturers make these measurements 
independent of industry standards, and in varying conditions. Additionally, a 
single statistic is not a reliable measurement of a product's 
performance. One could, for instance, find a very expensive system with exactly 
the same specifications as a much less expensive system. On paper, the 
two would appear identical. The difference in performance, however, 
would be significant. A better approach, we feel, is to listen to the 
product.


Thank you for contacting Bose Corporation.*


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## frustrated (Mar 21, 2011)

Have already given up on the folks at Bose (it's now a four letter word to me). Gutted the cabinets, will keep the 4 tang band tweets I bought for these, the 4 8" woofs surronds are in great shape and test at 8.2 ohms. Guess I'll build a pair of x's and enjoy the beautiful teak cabinets with new internals (have a set of 6.2 in teak for the rears, purchased in 1992!)


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## sickboy013 (Feb 28, 2009)

Good luck with your project. It's too bad Bose won't provide that information when asked. Oh well, what can you do.


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## MatrixDweller (Jul 24, 2007)

sickboy013 said:


> .
> *Additionally, a
> single statistic is not a reliable measurement of a product's
> performance. One could, for instance, find a very expensive system with exactly
> ...


I like this quote. I sort of makes me laugh. It's saying that if two systems were benchmarked and the tests showed both speakers to be equal then the more expensive one is still better. :coocoo:


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## Mark Techer (Jan 17, 2008)

Sorry if this comes off as a BOSE bash. I just thought I'd share some of my BOSE experiences.

I don't anything about the 10.2 system, but I do know a little bit about some of the X01 series from the late 1980's. 201, 301 401 and 601 were all 2 way, ranging from 2 to 6 drivers with 901 being their flag ship using 9 of their 4 1/2" drivers. 

Anyway back then, they did publish some specs of the crossover of speakers like the 301 was a 6dB/oct LP at 2500Hz and HP at 1500Hz. Note a massive overlap there which they claimed promoted the "essential mid range". 

A few years later I got to pull apart the 601 (basically a double up of the 301) and the wiring was 22 guage. It was thin. As I had suspected, single 100V caps for the HP filters and very small single coils for the LP. 10mm chip board enclosures laminated in what was supposed to be walnut. I also found a bird's nest along with part of the bird. It must have thought the port was a good place to nest. 

The funniest one was the 401 and it's "acoustic brick". This was a "tower" speaker (dual 6" woofer and single cone tweeter) that was top heavy, so to balance it up, they used a common clay house brick with a bolt to hold it in place. On the brochure, they showed a curved arrow which was supposed to be the direction of the sound inside the box reflecting off the brick. Talk about snake oil.


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## GranteedEV (Aug 8, 2010)

Mark Techer said:


> Anyway back then, they did publish some specs of the crossover of speakers like the 301 was a 6dB/oct LP at 2500Hz and HP at 1500Hz. Note a massive overlap there which they claimed promoted the "essential mid range".


While bose is not a company I would expect flat response from, I will say that electrical filters are not the same as acoustic filters. Such a crossover as you described is very much possible when you factor in natural driver behavior.




> The funniest one was the 401 and it's "acoustic brick". This was a "tower" speaker (dual 6" woofer and single cone tweeter) that was top heavy, so to balance it up, they used a common clay house brick with a bolt to hold it in place. On the brochure, they showed a curved arrow which was supposed to be the direction of the sound inside the box reflecting off the brick. Talk about snake oil.


:rofl:


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## gibroni (Sep 25, 2010)

I like these kind of projects. The 10.2 uses an 8" woofer in the top and an 8" woofer in a bandpass enclosure below. You're interested in the cabinets but not so much the electronics. Good. Measure the boxes, find woofers that would work well in that space. That bottom section could easily be converted to a dual 8" ported sub. The You could plug the Bose tweeter holes, the grill covers them anyway. Good luck and keep us abreast of your progress. :T


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## Mark Techer (Jan 17, 2008)

GranteedEV said:


> While bose is not a company I would expect flat response from, I will say that electrical filters are not the same as acoustic filters. Such a crossover as you described is very much possible when you factor in natural driver behavior.


Yes, this idea works when you need to make the crossover slope steeper. THX even did this for their 80HP section where the electronic filter HP slope is 12dB and the sealed LCR speakers F3 is 80Hz (also rolls off at 12dB/oct). The combination equates to a 24dB slope, however this is not quite the same. There is a 45 degree phase shift for each cap (-45degrees) coil (+45degrees) added, so a 1st order network is 90degrees out of phase. A 2nd order network uses 2 caps and 2 coils and is 180 degrees out of phase. This is easily corrected by reversing the polarity if the tweeter. 

All BOSE did when choosing a 1st order crossover was to save on production costs and because they only used 100V caps, the saving was not huge anyway. 

Another tail from the BOSE side. If you remember back a few years, BOSE was able to claim "unlimited power in a non commercial application" for their 901. As it turns out, each of the 9 drivers was just 0.9ohms and rated at 50 watts each. The 9 drivers were all wired in series giving a total of 7.2 ohms and 450watts. 

Question: Who in their right mind would wire speakers in series? :coocoo:


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## ISLAND1000 (May 2, 2007)

You could buy a Smith & Larson WT 2 woofer tester and measure your drivers for the T/S parameters.


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