27TDFC and Scan-speak 18S/8531G

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Hello all. I just built new speakers with 27TDFC tweeter , Scan-speak 18S/8531G woofer and PartsExpress 1q ft closed cabinet. Tweeter is installed in waveguide and for it's crossover just one capacitor is used. It's done exactly as in Zaph's TMM design. For woofer I use 2.2mh inductor, temporarily. I'll
make line level filter for it later. These speakers are driven by 4 channel amp, so tweeter level is adjusted with amp gain and room induced bass boost 60-110hz is corrected with parametric equalizer -4db.
I just can't believe how clean these speakers sound. Even when amp is playing at full power(45w per channel) there is no audible distortion :bigeyes: I guess they will be even better after I replace 19ga inductor with line level filter.
 

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Great looking speaker and I'm sure it does sound great too. Is this your first project? I use the 27TBFC/G + Dayton RS 6" in my speakers and they are incredible. I would consider a Scan Speak as the ultimate upgrade but Usher makes some serious contenders too.

What exactly is your crossover design? I'm not sure I'm following what you did - do you have a schematic? I'm not sure exactly what you mean by "line-level filter" either - do you mean an active crossover?
 
actually it's my second multi driver speaker project, first one was bamtm.
crossover is very simple just a 2.25mfd cap on tweeter
and inductor on woofer. i just thought it doesn't make sense to design complicated crossover: 1.drivers don't have breakups to worry about 2.one speaker has to be put between wall and large tv, so equalizer must be used anyway.
no, i don't want to make active crossover(for now), just cap and resistor before amplifier, like here: http://www.t-linespeakers.org/tech/filters/passiveHLxo.html
well, in the future i'll make active crossover/equalizer, i just don't have enough knowledge to do it now.
 
Did you calculate a crossover point? A 2.25 mfd cap should start to slope an 8 ohm tweeter above 8,000 Hz, and a 2.2 mH inductor should start to slope the woofer around 600 or so. Unless I missed something? Even lower impedences skew the values farther.

You could have a serious dip in your midrange frequency response here. I'm all for simplicity, but the XO components should at least cross at or near the same point. A first order crossover is usually discouraged in a 2-way design, especially for the tweeter.

You've spent a lot of money on these speakers - the crossover doesn't have to be complicated but I think you have less than the minimum here; they may sound good now but I suspect there could be a significant audible improvement with an adjustment in the crossover.
 
I agree with you, I am definitely going to work on better crossover.
for now:
tweeter section is done exactly as described here: http://www.zaphaudio.com/Waveguidetmm.html

and I agree inductor is too big, it will be replaced with line level filter anyway.
I don't want any inductors in front of such nice woofer :)
there is indeed a dip around 1khz, but I like it, it gives mellow relaxed sound :)
 
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