EL166 "built in baffle step compensation"

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http://www.creativesound.ca/pdf/EL166-data-100610.pdf

Hi,

An interesting claim without stating the required baffle width.

2 – Built-in Baffle Step correction @ +5dB lift from 300Hz to 800Hz

Well that's not right is it ?

And the published response is :

Anechoic on IEC baffle

Erm... an IEC baffle is not typical box.

IEC%20baffle.jpg


"The smallest baffle listed applies to drivers 8" and smaller."

There is is no sign whatsoever of inbuilt BSC compensation.

rgds, sreten.
 
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There are some quality drivers which have been designed with a smooth rise at the top end. This has been engineered to begin directly above the baffle step associated with the most common baffle expected to be used (which I guess would be just wider than the driver). This way you end up with a constant rise all the way up so you only have to add one order to your filter and you can get a smooth rolloff simply.

I'm not sure what to make of this example though. That's a nice peak in the response which I guess could be exploited. The bottom line though, if I were going to use this driver seriously I would treat it the same as any other.

I used to own a car that had a hole in the floor, but I preferred to call that my air conditioning system. :D
 
Mark mentioned how the built in BSC works:

Hi Apt, Chris (your post 232), Fellas.
Ummmmmmph..........BSC (BTW, also stands for "British Sugar Corporation", a little bit of trivia for your amusement):D.

Right oh, let me have a go at explaining how BSC is done. First off, take another look at the FF125WK. At first glance, it looks similar to the Alp10 Gen. 2, similar cone and coil dimeters etc., but the devil is in the detail:

Compare the 125's and Alp10's coil winding lengths and/or X-max, quoted SPL's and Mms. Note the short coil, smaller X-max, lighter Mms and higher SPL on the 125WK. These features are the tell-tail signs of the designers intension to give efficiency the priority. Now read Dave's (Planet 10) post No. 82:

Alpair 12P Gen. 2 (paper cone)

So, to get more bass, I long ago (2003) started experimenting with "long throw-light mass" power-train designs. Most Full-Range driver designers won't venture into this territory as controlling mechanical distortion within the power-train under load is a nightmare. Added into the mix is the tougher challenge to accurately manufacture such power-train components. The difficulty assembling said parts also increases, climbing reject rates usually results.

I've now got to the point in development where I've overcome most of the challenges and can design and produce drivers that are mechanically efficient in the lower ranges. The driven power consumption (loss) to mass ratio is lower, thanks mostly to the work of the suspensions and mass reductions in the critical components of the power-train.

Try this method/observation: Take an Alpair 10, place on a desk or table, cone face up. Place your fingers on its dust cap and VERY GENTLY push downwards. Note how easy the power-train stroke extends (DON'T GO TOO FAR). Note the 10's linearity. It takes the same light effort to push the power-train all the way to around 8-mm before you'll start to feel increased resistance. At this point, STOP pushing and RAPIDLY take your fingers off the cap. Note how the 10's power-train returns to its rest position. Its very fast with no bouncing, it gets to its rest position and stops.

Now try the same method with a 125WK (or similar) and you'll immediately feel the difference in the compliance. Likely you'll only be able to push its power-triain 2 or 3mm before it tightens up.

So fellas, this a quick potted history on how I do BSC. Along with my suggested driver demonstration/observation, hopefully should give you a fair practical idea of differences in the design approach to the drivers.

The end result is most Marlaudio drivers generate an emittance gain in the lower ranges.

Have fun and cheers

Mark.



http://www.diyaudio.com/forums/markaudio/154837-marks-proto-6-5-woofer-1-silk-tweet-combo-9.html
 
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