Hi, Merry Christmass and last week of the year according where you 're living. (Santa, drop me your number please as I was dropped a 5 yo kid gift and eventually think there is a mistake ?!)
I would like to pad down a plateau magnitude raise on the middle of a tweeter magnitude.
A serie resistor (already existing in the filter) at the input of the passive crossover circuit is calling my noob skills for an inductor 0.5 to 1 mH parralel, to make a smooth spl notch in spite of a parallel notch with the tweeter inputs to pad down till 1 to 3 dB
I will adjudt by listening in the listening room that inductor value.
I still have to measure with better precision and better gating - 6 ms window perhaps at 1 meter then listening spot at 2.5 meters centred- the standalone tweeter response above 1500 hz. The filter being two 12 dB nodes in serie to make a sorta 24 db hybrid two nodes passive filter with a car tweeter that needs steep slope because the highish Fs for protection before the second electrical cut-off giving the near acoustical filter. I dunno if my english skills are acurate enough for the description to be understood, appoligizes if so.
I know the added parrallel coil with the serie teeter resistor will add + 90° phase change, rigth ? And a non dangerous for the amp, raise of the impedance in that area ?
Am I correct ? Why btw do we not seen that more often in tweeter filters ? Like if experienced designers prefer more global L-Pad attenuation than correcting the middle range of a tweeter non smoothness, we can by the way more often see with a resistor // caps that raise the ending level with a bigger first R attenuation ?
Any thougth on that, is it an issue to introduce a serie coil on a passive filter ? I ask cause I never seen one in my limted experience for a tweeter which has in serie caps and only // coils from 12 dB and upper slopes.
Many thanks
I would like to pad down a plateau magnitude raise on the middle of a tweeter magnitude.
A serie resistor (already existing in the filter) at the input of the passive crossover circuit is calling my noob skills for an inductor 0.5 to 1 mH parralel, to make a smooth spl notch in spite of a parallel notch with the tweeter inputs to pad down till 1 to 3 dB
I will adjudt by listening in the listening room that inductor value.
I still have to measure with better precision and better gating - 6 ms window perhaps at 1 meter then listening spot at 2.5 meters centred- the standalone tweeter response above 1500 hz. The filter being two 12 dB nodes in serie to make a sorta 24 db hybrid two nodes passive filter with a car tweeter that needs steep slope because the highish Fs for protection before the second electrical cut-off giving the near acoustical filter. I dunno if my english skills are acurate enough for the description to be understood, appoligizes if so.
I know the added parrallel coil with the serie teeter resistor will add + 90° phase change, rigth ? And a non dangerous for the amp, raise of the impedance in that area ?
Am I correct ? Why btw do we not seen that more often in tweeter filters ? Like if experienced designers prefer more global L-Pad attenuation than correcting the middle range of a tweeter non smoothness, we can by the way more often see with a resistor // caps that raise the ending level with a bigger first R attenuation ?
Any thougth on that, is it an issue to introduce a serie coil on a passive filter ? I ask cause I never seen one in my limted experience for a tweeter which has in serie caps and only // coils from 12 dB and upper slopes.
Many thanks
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Sometimes it's possible to guess these things but a simulation could reveal unexpected behaviours. Perhaps you could post a picture of the response shape you are dealing with, and the circuit.
Hello,
Thanks to shimm in.
Not made a whole sim for now as coils of the two serie 12 dB are not individually measured yet (I still have to purchase a DVM that has henri measurement stuffs in it in spite of my basic DVM. Dunno if Arta or else can give Henri measurement related to frequencies ?
What is worrying me in that added coil scenario is a mismatch phase tracking between the medium low pass and the tweeter high pass passband area.
In less technical words, I wonder from an unexperienced point of view as mine if subjectivly there, the EQ shapping can be musicaly better than a phase mismatch the added coil introduce. Because, timing is important for transcient, bass snap, etc. And two serie 12DB slope serie is already 360° phase late already vis à vis of the medium driver ?!
Edit : for sure I could just try and check from a subjective listening test, but would like to know if it is a proper way to tweak, by adding passive stuffs or else with passive designs. Understand : in spite of changing for a better suited tweeter and redisigned filter for it
Thanks to shimm in.
Not made a whole sim for now as coils of the two serie 12 dB are not individually measured yet (I still have to purchase a DVM that has henri measurement stuffs in it in spite of my basic DVM. Dunno if Arta or else can give Henri measurement related to frequencies ?
What is worrying me in that added coil scenario is a mismatch phase tracking between the medium low pass and the tweeter high pass passband area.
In less technical words, I wonder from an unexperienced point of view as mine if subjectivly there, the EQ shapping can be musicaly better than a phase mismatch the added coil introduce. Because, timing is important for transcient, bass snap, etc. And two serie 12DB slope serie is already 360° phase late already vis à vis of the medium driver ?!
Edit : for sure I could just try and check from a subjective listening test, but would like to know if it is a proper way to tweak, by adding passive stuffs or else with passive designs. Understand : in spite of changing for a better suited tweeter and redisigned filter for it
Yes, but I still don't know what your response looks like and what you circuit looks like.
Aha, yes we can discuss the effects and we can also discuss solutions.
Sure. Resonate with a known capacitor, set against a resistor and sweep the Voltage across it until you find the peak. Calculate the value.
