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SBAcoustics 61-MFC |
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"MFC" is polypropylene, here mineral filled polypropylene as is for my
reference ATS4 midrange drivers. Having full symmetric drive and a
proper ventilated magnet system, this driver provides a sonic signature
very much like the AT 18H52 driver. I like it. I've gotten used to it
over the last 3 years. Good PP cones fitted into a proper magnet system
and basket usually deliver some extra dynamic headroom compared to
hard-cone drivers. PP break up in an ear-friendly way. I honestly don't
think PP cones offer less resolution compared to hard-cones, but they do
it in another way which is as hard to describe like the taste of wine. The construction here differs significantly from the -61AL version due to a low-order LR2 filter. The smooth response and roll-off characteristic of the PP cone allows a very simple crossover and the alu tweeter has no trouble following the trend. I'm sure I'll have the question which I prefer, the AL or the PP. Please spare the mail because I like them both for what they do their way. And their way is not only due to cone material but also crossover topology. Only thing I'll say is that if you think alu sucks, built it and tell me if you still think so. You may be pleasantly surprised. If you wear belt and suspenders build the PP.
Basics:
2-way 16 liter speaker from 6" mid-bass and 1" dome tweeter. System sensitivity: 85 dB. Impedance: 8 Ohms, 6 Ohm minimum. Power handling: 60 watts, and please read here: http://www.troelsgravesen.dk/power-handling.htm. Any burned driver is a misused driver! Point of crossover: 2600 Hz, 2nd order LR2 topology. Useful links (Please follow all links before e-mailing!): http://www.troelsgravesen.dk/tips.htm http://www.troelsgravesen.dk/tips.htm#CONSTRUCTION_OF_CROSSOVERS http://www.troelsgravesen.dk/crossovers.htm http://www.troelsgravesen.dk/LCR-RC.htm http://www.troelsgravesen.dk/Inverted-Polarity.htm http://www.troelsgravesen.dk/choices.htm http://www.troelsgravesen.dk/power-handling.htm Download data sheets here: SB17MFC35-8 SB26ADC-C000-4
Crossover components' values come with Kit Instruction.
Go to SBA-61-NAC for cabinet details and construction. Everything that can be counted does not necessarily count; everything that counts cannot necessarily be counted". Albert Einstein. A few comments on MEASUREMENTS before you start
interpreting all the readings below.
Above you see the same graph presented with the
same 50 dB scaling, but at
different width and height. Now, we may think the graph to the right looks rather
rugged, but if we stretch out the presentation (left) it suddenly looks
rather smooth. The left presentation is often used by driver manufacturers to make their frequency response graphs look better. If we
apply e.g. 1/6 or 1/3 octave smoothing things look even better. Just
this to display how easily measurements can be manipulated to look nice.
SBA 61MFC MEASUREMENTS
Crossover components' values to come with the kit.
All kit and component prices may be subject to change and are always to be confirmed by Jantzen Audio Denmark. Download Kit Sale Presentations: All technical questions to troels.gravesen@hotmail.com All questions regarding purchase of kits, please mail Jantzen Audio at contact@jantzen-audio.com
CROSSOVER-LAYOUT
For level 2, the Superior-Z caps (C1 and C3) are replaced with
STANDARD-Z caps. No other changes. WIRING
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