Most impossible to answer B&W Question, ALL Prestige/Marlan-head FST...Owners only?

[BassThatHz]

I'll get into the why part and save acoustical discussions, pros/cons for later... but first I just need to determine if this is even physically possible to implement.

I was looking at http://www.bwgroup-support.com/partspriceavail.html and saw many FST mids that are potentially swappable into my N803’s (drivers that are better than the default units).

LF00264 803D 3-4S
LF00315 HTM2D 3S
ZZ12998 SIG HTM
ZZ12777 SIG 800
ZZ11290 N801-2
ZZ13013 N800
LF00175 800-1-2D

Which ones match the mounting depth, drawbar thread size and driver diameter to the N803? [Measured accurate to 1 millimeter or something?]

I've never even seen the magnet structure of these units, so I can't even start to guess at the answer without purchasing them. (pictures welcomed)

If the drawbar thread-size doesn't fit... then perhaps it is simply a matter of ordering a matching drawbar/drawbolt, that's assuming it would then match the box length and existing rear-isolator drawbolt box hole?

OMG is this not the most impossibl-est to answer B&W question of all time... EVER!!! ? :thud:

I have emailed this question off to B&W today (fingers crossed).

;x( Any Sig-Prestige/Diamond/Marlan-head owners brave enough to pull out their FST's and measure/take pics?
Any B&W designers/factory-workers in the audience?
Anyone who has actually attempted this mod?

[Race Car Driver]

See this thread

http://htguide.com/forum/showthread.php4?t=35382

I have take apart just about everything on my N802s, HTM2d, and even some of my past B&Ws.

If there is anything you want me to measure, I galdly will. They are just speakers, held together by just nuts and bolts

Inside the 855

http://htguide.com/forum/showthread.php4?t=29490

Some pics of the N802s. I have more of this I could add.

http://htguide.com/forum/showthread.php4?t=25547

[BassThatHz]

My tape measure is only good for 1/16th of an inch.
This is what I need to determine, roughly, to know if it fits inside my older N803. I have number coded the measurements to make it easier to explain.

N803 FST Diameter[0]: 6 5/8" Mounting Depth[1]: 3 5/16"
Drawbar Length[2]: 12 3/4" Thread Length[3]: 9/16" Thread diameter[4]: 3/16"
Drawbolt hole Diameter[5]: 3/8", Length[6]: 1 1/16"

[BassThatHz]

oops what was I thinking...

This is the mounting depth[7]: 2 7/8"


The measure [1] is the height of the FST.

[scanido]

Good to see some willing modders here!

WAs taking out the FST driver difficult?

[jamesdaman]

is there ANYWAY to make the 805S any better?? Id love to think im brave enough to mod it if shown how

[BassThatHz]

Removing the FST is easy.

That rod and bolt in the back is the only thing keeping it from falling on to the floor.

Have someone ready to catch the driver, then just undo and remove the bolt in the back and push on that internal rod. (Depending on how stuck it is... you may have to push on it REALLY hard.)

Take a picture of the driver and of the two wires before you remove them, so you can put it back in exactly the same way. (If you want, you can even count the number of turns to the bolt as well.)

[Antus]

the FST are not attached by bolt, it should be a easy fit. however, u may need to use the rod from the original one to get the proper length.

I think the best you can fit is the 802D FST driver, which has a bullet shape thing attached to the end of the driver.

There are another ways to improve sound. upgrade the crossover. on the old N series, B&W use some cheap stuff, like iron core inductor and cheap capacitor. u can upgrade with all air core. use 10GA or 12 GA for bass, and 12 or 14GA for mid and tweeter. upgrade Capacitor to Mundorf silver/gold/oil for tweeter, mixture of silver/gold, silver/oil, and Spreme for midrange. regular MCap for woofer.

If you want to do even further mod, u can upgrade the internal cable. 10GA for bass, 12GA for mid, and 14GA for tweeter. u can kick up a notch with silver plated copper for tweeter depends on ur perferance.

[BassThatHz]

B&W basically said that nothing would fit or sound proper, which I anticipated.
Is that true though... or is that just company speech?

I always thought that the driver was always the biggest limiting factor in regards to distortion and linearity.

Using the existing crossovers which all have ("almost") the same filter properties and slopes, can't be THAT far off to distroy the sound.

The odds seem stacked against me and unless somebody speaks up who has actually heard an "interbreeded" FST in action before with good results and has size measurements & pictures to prove that it fits in, than I'm not going to take the financial risk in being the first one to start this and end up being wrong and short several hundred $ for no sensical reason.

[Race Car Driver]

They look very similar to the N802 drivers I had.(sold em)
Ill get around to getting measurements of my N802s and HTM2d one of these days that I can take them apart.

As long as the basket seals in the opening I dont see what the big deal is. Drawbar length can be added or subtracted rather easy.

[Gianluca]

Just a question:

I just bought some parts from B&W, but before they ship they asked for serial numbers. Would they not refuse to sell drivers if you don't have that particular model driver in your box.


Used is a whole different story.

Luca

[ckunstadt]

the FST are not attached by bolt, it should be a easy fit. however, u may need to use the rod from the original one to get the proper length.

I think the best you can fit is the 802D FST driver, which has a bullet shape thing attached to the end of the driver.

There are another ways to improve sound. upgrade the crossover. on the old N series, B&W use some cheap stuff, like iron core inductor and cheap capacitor. u can upgrade with all air core. use 10GA or 12 GA for bass, and 12 or 14GA for mid and tweeter. upgrade Capacitor to Mundorf silver/gold/oil for tweeter, mixture of silver/gold, silver/oil, and Spreme for midrange. regular MCap for woofer.

If you want to do even further mod, u can upgrade the internal cable. 10GA for bass, 12GA for mid, and 14GA for tweeter. u can kick up a notch with silver plated copper for tweeter depends on ur perferance.

oooh! That sounds fun. Where can I get more info on that? I don't want to solder much... does anyone sell a drop-in crossover for a N803??
thanks!