Hi,
i have 1 pair of audax HM170G8 and 1 pair of audax TW034XO tweeter.i interest for building 2 way loudspeaker,anyone have suggest about box size and crossover schematic for this configuration?
i have 1 pair of audax HM170G8 and 1 pair of audax TW034XO tweeter.i interest for building 2 way loudspeaker,anyone have suggest about box size and crossover schematic for this configuration?
I only know the HM170G8, and this woofer works perfectly in an 18 - 22 liter cabinet. With a F3 of about 50 hz. A simple first or second order x-over suffices.
The TWO34 has its fundamental resonance below 900Hz, so it works well with a first-order crossover if you are setting the nominal crossover frequency to 3000Hz or so.
It WILL need a series L_C_R network across it to compensate for the rise in impedance at resonance. (Otherwise you'll find that your high-pass filter isn't behaving as you expected it to).
I use this tweeter myself with such a crossover with no problems.
(If no-one responds with the resonance compensating network values, I'll check this evening with what I used and post it tomorrow).
Chris Morriss.
It WILL need a series L_C_R network across it to compensate for the rise in impedance at resonance. (Otherwise you'll find that your high-pass filter isn't behaving as you expected it to).
I use this tweeter myself with such a crossover with no problems.
(If no-one responds with the resonance compensating network values, I'll check this evening with what I used and post it tomorrow).
Chris Morriss.
As a resonance compensating network, I use a series L-C-R network of 1.2mH, 33uF, 10R across the tweeter.
To make a first order crossover work adequately, it would also be wise to place a network across the bass unit to compensate for the rise in impedance as the frequency increases. For the HM170G8, a series R-C network of 8.2R + 12uF is about right.
The resonance compensating network across the tweeter, and the inductance compensating network across the bass unit means that the drive units now present a much more constant impedance load to the crossover.
With these networks in place, you can then calculate the value of the series 'L' for the bass unit filter, and 'C' for the tweeter filter, assuming a constant 8R load. (It won't be perfect, but it will a LOT better than if the speaker impedance had not been compensated for.)
The resonance compensating network across the tweeter, and the inductance compensating network across the bass unit means that the drive units now present a much more constant impedance load to the crossover.
With these networks in place, you can then calculate the value of the series 'L' for the bass unit filter, and 'C' for the tweeter filter, assuming a constant 8R load. (It won't be perfect, but it will a LOT better than if the speaker impedance had not been compensated for.)
Ouroboros said:
I used 10ohm + 10 uF zobel on the woofer. And a 18 liter enclouser tuned to 50hz.
Actually you really need to measure the resonant frequency of the bass unit in its cabinet to determine the resonance compensation network. I've only ever done this for sealed box systems.
(Reflex loudspeakers are the work of the devil! (IMO of course)
(Reflex loudspeakers are the work of the devil! (IMO of course)
Oh Oh, I really should THINK before posting!
There's only an inductance compensating (Zobel) network on the bass unit. No resonance compensator!
!0r + 10u or 8R +12u aren't too much different in real life.
(I now go away and hang my head in shame)
There's only an inductance compensating (Zobel) network on the bass unit. No resonance compensator!
!0r + 10u or 8R +12u aren't too much different in real life.
(I now go away and hang my head in shame)
hi everybody,
how about inductor value for this HM170G8?assume use 18 litre box in 50hz.
So the zobel network is 10 mf + 10 ohm.I will try it.
how about inductor value for this HM170G8?assume use 18 litre box in 50hz.
So the zobel network is 10 mf + 10 ohm.I will try it.
for a x-over around 2500hz use 2.0 - 2.2 mH air-core inductor.
See the freq-plot below. In my room measuring <200hz isn't possible the curve is smoothed with 1/6th octave. Used tweeter is a 19mm Scan Speak.
See the freq-plot below. In my room measuring <200hz isn't possible the curve is smoothed with 1/6th octave. Used tweeter is a 19mm Scan Speak.
An externally hosted image should be here but it was not working when we last tested it.
http://pageperso.aol.fr/petoindominique/doc_htm/hm170g8.htm
The rise of the bass unit response above 1kHz indicates it will
work well in combination with a "Baffle Step Compensation"
inductor, giving a final rolloff of 2 to 3 KHz.
(a parallel resistor can be used for fine tuning)
BSC is mandatory for a good tonal balance.
The tweeter is far more more efficient and will need padding
down with series and parallel resistors. The parallel resistor
will suppress the resonance impedance peak and the network
for impedance compensation will probably not be needed.
🙂 sreten.
The rise of the bass unit response above 1kHz indicates it will
work well in combination with a "Baffle Step Compensation"
inductor, giving a final rolloff of 2 to 3 KHz.
(a parallel resistor can be used for fine tuning)
BSC is mandatory for a good tonal balance.
The tweeter is far more more efficient and will need padding
down with series and parallel resistors. The parallel resistor
will suppress the resonance impedance peak and the network
for impedance compensation will probably not be needed.
🙂 sreten.
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Hi everybody....I still in project for HM170G8.
I need cutting at 3150hz so i spec down the inductor value...that will no problem with cutting frequency...
the main problem is centre frequency at 1-1.25khz khz ia peak at 3db.someone have schematic in passive x-over for reduce this peak?...all is very linear except this freq...
now i use 6db with zobel in woofer x-over
I need cutting at 3150hz so i spec down the inductor value...that will no problem with cutting frequency...
the main problem is centre frequency at 1-1.25khz khz ia peak at 3db.someone have schematic in passive x-over for reduce this peak?...all is very linear except this freq...
now i use 6db with zobel in woofer x-over
Hi Sreten,
i see at:
http://pageperso.aol.fr/petoindomin...htm/hm170g8.htm
but i don't know france language 🙂...may i know about your baffle step compensation,is this for reduce 1 khz?...
i see at:
http://pageperso.aol.fr/petoindomin...htm/hm170g8.htm
but i don't know france language 🙂...may i know about your baffle step compensation,is this for reduce 1 khz?...
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