No not necessarily. Assuming that it is a second order filter (inductor and cap) then the inductor and capacitor form a resonant circuit, with the loop closed by the amplifier. This determines the 'Q' of the crossover filter. If you add ESR it will lower the Q of the filter. The parallel load (driver and resistor attenuator) also alter the Q, hence why it is important to sim a crossover and why the inductor/cap values have to be different for different speaker impedances. A sim will help you determine how much ESR is tolerable in your design. In some cases adding ESR intentionally by the use of an actual series resistor may actually be desirable to reach the target curve.
Agreed. But I assumed that the C was in series with 2 x R as that is what the OP implied, and no circuit was shown. In that case the ESR is irrelevant. But yes, in another circuit it may be of consequence.
BTW Even with an L if the ESR of the C is in the same order of magnitude or smaller than the R of the L wire, probably no issue either.
But let's have the circuit then.
Jan
BTW Even with an L if the ESR of the C is in the same order of magnitude or smaller than the R of the L wire, probably no issue either.
But let's have the circuit then.
Jan
Sorry for any confusion...
The filter is a third order high pass, 10uF, 1mH, 35uF
And after this a series R and a Rpar across the speaker (TD2001).
The thing is, I use DTAC capacitors and out of curiousity I had some ABX sessions switching the 35uF DTAC with an russian PIO and secondly with a couple of regular MKP in parallel adding up to 35uF.
Switching was done with 2 relais close to the filter while listening to a brief repeated A-B track from a CD.
The Russian comparison was extreme...wife/son blindly could also detect this 100% accurately.
Compared to the regular MKP, the difference was smaller but still noticable.
No difference in SPL curve, Impluse, Group delay, Phase (CLIO)
So it made me think...why? ESR? And if, would it get even better if I did need the attenuating resistors behind this filter? And perhaps move the attenuation before the complete third order HP?
The filter is a third order high pass, 10uF, 1mH, 35uF
And after this a series R and a Rpar across the speaker (TD2001).
The thing is, I use DTAC capacitors and out of curiousity I had some ABX sessions switching the 35uF DTAC with an russian PIO and secondly with a couple of regular MKP in parallel adding up to 35uF.
Switching was done with 2 relais close to the filter while listening to a brief repeated A-B track from a CD.
The Russian comparison was extreme...wife/son blindly could also detect this 100% accurately.
Compared to the regular MKP, the difference was smaller but still noticable.
No difference in SPL curve, Impluse, Group delay, Phase (CLIO)
So it made me think...why? ESR? And if, would it get even better if I did need the attenuating resistors behind this filter? And perhaps move the attenuation before the complete third order HP?
Why not set the attenuator to what you require & replace with a resistor. While we’re on the topic may I introduce you to a film resistor that I’ve been playing with, its the most neutral that I’ve tested & this includes Mills Mra 12, Mundorf M resist Supreme & Jantzen. Very even sounding & transparent from top to bottom. Not expensive when compared to Mundorf. Try it sometime guys, don't think you will regret it. Powetron FPR2-T218 oh you must add a heat sink to it.
Cheers
Cheers
Oops Im sorry thought that its a variable type. In which case if your after minimum changes to Sq you can try what I suggested. My ML XO is just like yours Caps before resistors.
Btw Arno the type resistor used will do far more harm to the sound if not correctly choosen
so it’s really a mooted point to worry about the Esr issue.
Cheers
Btw Arno the type resistor used will do far more harm to the sound if not correctly choosen
so it’s really a mooted point to worry about the Esr issue.
Cheers
ESR would be a logical and sufficient explanation for some of the sound differences... without opening a can of worms. We can stop there...
Do try other capacitors, but within the MKP territory sound differences tend to be rather small.
Do not move whole L-pad before the HP filter! You can try with moving only the serial resistor before the filter (this will require some L and C values adjustments), but the resistor parallel to driver must stay after the filter.
If there is no measureable difference it most probably is not the ESR, because that would be measurable.
Jan
The simplest explanation would be value differences between the parts, leading to changes in freq response. That can be quite audible. These large caps often have tolerances of 10% or more. That's why I asked about that.
Jan
To quote OP:
So, the mystery remains.
Opening a can of worms about sound differences in capacitors is in the view...
Effect of ESR on the frequency response between bipolar electrolytic and MKP capacitors (with the same cap. values) is small but measurable. And possible to hear.
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