L-pad on woofer, though feasible, is not particularly good idea. If i'd make some atenuation of that sort, i'd probably use series woofer coil for it. Rdc can be anything from 0.25-1 ohm. Any larger value than that and i'd do biamping.
I tried 4 ohm series coil for a specific subwoofer aplication some 10 years ago. It worked without a problem but the coil got warm (not hot) when playing really loud. You'd need heck of a resistors to make an L-pad that would be immune to that. Not to mention the decadency of spending so much power on fancy heater
Changing series rdc in front of woofer will affect the Q of the speaker but since you are using it sealed, it is negligible.
The smartest thing would be, in my opinion, to totally redesign the crossover or to use biamping: woofer on one amp, mid-hi on another with the existing crossover.
Again I agree
Bi-amping would be my first choice but its not exactly a cheap solution 
And for dissipation on L-pad I was surprised that X sim etc. shows much much less dissipation from existing R11, and again I have planned to make one just as trial to hear where it takes me...
Not cheap of course but it doesn't have to be expensive either. BatoMM with two lm3886 bridged with its 70W/8 ohms and remote feedback function will get you there for about 150€ in parts for two monoblocks without chassis. To save the money on chassis you mount the amp on 4mm thick aluminium plate and make your own plate amp but one of high quality. You can use EI transformer and mount it separatelly on the other side of the speaker cabinet - no need for toroids because things aren't clustered in a smallish chassis.
That's what i considered doing before i sold my Beyma 15K200 and with that act i exited the hi-eff crowd
That's what i considered doing before i sold my Beyma 15K200 and with that act i exited the hi-eff crowd
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This is not exactly on resistors in speakers, but I'm putting it here because SBA10 crossover has several resistors that are HEAVILY underrated so everyone who has bought and build the kit is welcome to contact me PM and I'll point the weak spots.
From the Test Bench: Resistor noise and non-linearity - Audio Precision
dissipation on 10W resistor @100W
From the Test Bench: Resistor noise and non-linearity - Audio Precision
dissipation on 10W resistor @100W
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Jantzen C-Coils have very low resistance, 13AWG 22mH is only 0R15
Bass coils must handle high power, they need to be heavy wire and thus low resistance. Air cores have higher R, but how about heat then with higher AWG like 15?
Component values are not public, I used 20-22mH, check links.
This pic is from TG's website
Bass coils must handle high power, they need to be heavy wire and thus low resistance. Air cores have higher R, but how about heat then with higher AWG like 15?
Component values are not public, I used 20-22mH, check links.
This pic is from TG's website
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Easily no heat with up to 1 ohm coil Rdc. Voice coil will be fryed much before series woofer inductor with Rdc of 1ohm gets near the problem. The wire is usually 1-1,4mm thick for air coils that has to be slightly higher Rdc. Wire in voice coil hardly ever goes more than 0,3mm. It gets thicker only in car subs that have 4 layer coils or any 4 layer coiled sub for that matter.
In my project with Seas L15 i used 3mH - 7 ohm coil in notch filter so i had to add only 8.2ohm resistor in that notch to get me the attenuation i wanted. That little coil packs more power than any resistor i can put there, it makes the coil smaller so it can be easily fitted on the crossover board.
In my project with Seas L15 i used 3mH - 7 ohm coil in notch filter so i had to add only 8.2ohm resistor in that notch to get me the attenuation i wanted. That little coil packs more power than any resistor i can put there, it makes the coil smaller so it can be easily fitted on the crossover board.
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Yes, from a dampening standpoint, low DCR is better. I've had excellent performance results with these:
ERSE - Super Q
The photo is not from an air core coil, it has a ferrite core.
Impossible to reach such low inductance values without that "help", they are air core would be huge...
Only my two cents ....
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Hallo
Great job
I am looking to build SBA-10 for a long time. First high end speakers, and hopefully end game.
As same as you, a am not happy with design.
Can I contact you on PM for some questions?
Best regards
Milorad
Subotica
200 Hz is just fine in that application. Needs a new woofer if higher crossover is desired. IME.