@AllenB That's why I qualified my statement with the "IF THE SOURCE IMPEDANCE IS LOW" part.
AS SHOWN....those two shunt circuits will have no effect on the drive voltage to RL. And, even in a real-world situation, they would most likely have minimal/no effect on the drive voltage to RL. (Typical power amplifiers being close to voltage sources.)
You might also note the series and parallel blue labels are incorrect.....according to Cal.
Cal mentioned above he's never seen it in print. Well, this is yet another example of inter-changing of those terms in some internet references on this topic, (in print) as I contended.
But, maybe I should wait for the clouds to open and the light to shine upon me?
Hilarious.
Dave.
AS SHOWN....those two shunt circuits will have no effect on the drive voltage to RL. And, even in a real-world situation, they would most likely have minimal/no effect on the drive voltage to RL. (Typical power amplifiers being close to voltage sources.)
You might also note the series and parallel blue labels are incorrect.....according to Cal.
Cal mentioned above he's never seen it in print. Well, this is yet another example of inter-changing of those terms in some internet references on this topic, (in print) as I contended.
But, maybe I should wait for the clouds to open and the light to shine upon me?
Hilarious.
Dave.
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Yes, that's right.. but let's make it clear. Speaker builders may be interested in either of the two suggested uses, Zobel between the amp and crossover, or between the crossover and speaker. They have a number of differences in practice.
Each one could really be said to be either in parallel or in series, depending on which point in the circuit you reference. I'm not just saying this for fun, this kind of analysis is used as a teaching exercise.
"Each one could really be said to be either in parallel or series, depending upon which point in the circuit you reference."
Oh really???
Don't get yourself tangled up in pretzel logic on this. Dave.
A theoretical voltage source has a voltage output unaffected by load....zero source resistance....infinite current capability...etc, etc.
Our typical real-world audio power amplifiers are fairly close to those characteristics. (For the benefit of nit-pickers like @AllenB, there are obvious exceptions.)
Anyways, basic rules of electronics: Voltage is the same at all points in a parallel circuit. Current is the same at all points in a series circuit. (And many other rules.)
The one we're interested in here is voltage in a parallel circuit.
The pictorials in Post #34 (the ones on the right) show an AC source connected to the LC circuit and Rload....in parallel.
By definition (and observation), voltage is identical across LC and Rload. And, the presence (or non-presence) of LC does not change the voltage supplied to Rload.
But, in real world conditions, the AC source resistance/impedance can become significant. AND it is a series element.
By definition (and observation), voltage is still identical across LC and Rload. But, the presence (or non-presence) of LC could change the voltage supplied to Rload.
(We don't have a parallel circuit anymore. It's now a series-parallel circuit.)
The key point here is.....many of our real-world power amplifiers have really low source/output impedance. It's MUCH less output impedance (as a percentage) than our speaker loads, or an actual resistor or the intrinsic resistance of the LC elements in circuits like we're talking about here.
Thus, shunted networks (in the context of this thread) are primarily impedance compensation devices. They alter the impedance seen by the source, but not the voltage drive level to the load.
I hope that's clear. I'm doing this from my phone and don't have access to my computer drawing program.
Dave.
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This is full of sound and fury, signifying nothing.
It's the duty of the poster to make himself clear, and avoid ambiguity.
For example, one could simply say:
A parallel RLC network, connected in series with the driver.
A series RLC network, connected in parallel with the driver.
Note that the adjectives, parallel and series, immediately and properly precede their object, "RLC network".
They do not precede "driver" and so there is no possible confusion.
Any claims about electrical performance in a serious discussion should have diagrams and graphs, but they are conspicuously absent.
It's the duty of the poster to make himself clear, and avoid ambiguity.
For example, one could simply say:
A parallel RLC network, connected in series with the driver.
A series RLC network, connected in parallel with the driver.
Note that the adjectives, parallel and series, immediately and properly precede their object, "RLC network".
They do not precede "driver" and so there is no possible confusion.
Any claims about electrical performance in a serious discussion should have diagrams and graphs, but they are conspicuously absent.
None of this has to do with DC circuits. These are loudspeaker crossovers, after all.
Fixing resonance is usually a good thing. I have tried to show this here - https://www.diyaudio.com/community/...fix-resonance-or-ringing-to-advantage.352796/
Any of those configurations will have an impact on the driver response if the values of the components are chosen to appropriate values to have an effect. But pick strange values far off the nominal impedance of the intrinsic system and it has little effect. For example, one can put a 10Mohm resistor, 5nH inductor, or a 10pF cap in those positions in a speaker crossover where impedance is circa 10ohms and say it has no effect. But use something like 10ohms, 1mH, or 10uF and it will shape the response. We do this all the time in crossovers.
But to answer your question is it worth it to invest in LRC components for a notch filter. I assume the “invest” word means to use premium, boutique or expensive components. Probably not. Basic quality MKP film caps are $1 to $10 for typical values and similar prices for typical copper air core inductors. Changing from a $10 Audyn 400V MKP cap to a $200 Mundorf silver foil in oil is not going to be a huge difference (IMO). Better to invest $200 in a wide set of LRC “toolkit” of many values. Upgrade if you feel you need to but hard to hear the difference. I do agree that changing from electrolytic NP to film caps makes a bigger difference though. Sometimes adding a small 0.1uF film bypass cap helps a lot and is less expensive.
Here is a kit that is maybe $350 worth of reasonably priced but high quality components. Is a single boutique cap worth as much? I use this for all my crossover development work and I have enough parts to prototype almost any crossover in minutes.
But to answer your question is it worth it to invest in LRC components for a notch filter. I assume the “invest” word means to use premium, boutique or expensive components. Probably not. Basic quality MKP film caps are $1 to $10 for typical values and similar prices for typical copper air core inductors. Changing from a $10 Audyn 400V MKP cap to a $200 Mundorf silver foil in oil is not going to be a huge difference (IMO). Better to invest $200 in a wide set of LRC “toolkit” of many values. Upgrade if you feel you need to but hard to hear the difference. I do agree that changing from electrolytic NP to film caps makes a bigger difference though. Sometimes adding a small 0.1uF film bypass cap helps a lot and is less expensive.
Here is a kit that is maybe $350 worth of reasonably priced but high quality components. Is a single boutique cap worth as much? I use this for all my crossover development work and I have enough parts to prototype almost any crossover in minutes.
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