The Zobel Network explained

[@aweidenhammer]

“Probably more than you wanted to know.” Nope. I would love more of this!

[@jeffsloane8628]

Good job Paul. I'm a Mechanical Engineer, and even I understood your explanation. 🙂

[@Sam_CL350]

I like that speaker in the background Paul. I would give it a 10.😁

[@ptg01]

"Trying to keep it simple"... Electrical Engineering is quite complicated.

[@johnnytoobad7785]

Zoebel networks (for Power Amps) are just used to dampen "potential" ringing from the RLC network created by speakers and the crossover network. Some networks have inductors, some don't. The inductor helps improve the amps damping factor for reactive loads.

[@RaySpainPlayer]

Yes. Nicely described

[@LeonFleisherFan]

Short and to the point. I seem to remember the term is after the name of Otto Julius Zobel, not Zöbel (= Zoebel).

[@PebblesChan]

Aren’t Zobel prizes are awarded to Audiophiles?

[@stephenstevens6573]

No. That would be a $obel prize...the more money you throw at a problem, the more problems you encounter, thereby proving that if funds are unlimited, you can buy from PS audio and be guaranteed to have issues that only can be solved by throwing MORE money at it!!

[@grumpy9478]

@@stephenstevens6573 the Zobel typology is often applied when managing special interest pursuits. it is a method to smoothly distribute one's available funds across multiple competing interests. Mrs. Zobel was the inspiration.

[@stephenstevens6573]

@@grumpy9478 Mrs. Zobel is ALWAYS the best at the redistribution model!!

[@Roosville1]

The speaker and crossover produces a complex fluctuating resistance (impedance) to the amplifier which is reactive and changes with frequency. A Zobel network attempts to add apply an opposite value impedance which when combined with the speaker impedance acts to flatted the impedance curve out, in theory presenting a load that looks more like a simple resistor for the amplifier to drive. A capacitor-resistor Zobel network is a crude first order conjugate match which takes out the worst of the impedance fluctuation. More technical is a conjugate match which I suppose in a way you would call a “supper Zobel network” It would require multiple inductors, capacitors and resistor values. Dynaudio used to conjugate match a lot in the ’90’s

[@ford1546]

I see that many people who make zobel network insert this towards the end of speaker crossover construction. shouldn't zoble be put in almost first and then design the rest of the crossovers around it? If you put in zoble last, the frequency will change too much?

[@ford1546]

There are other KZbinrs who explain (zobel nettwor) better. (zobel network) is a capacitor and a resistor connected in parallel with the speaker element. If you connect a coil in series with a speaker element and then connect a capacitor in parallel across +- on the speaker, you will experience that you will get an effect exactly as if you inserted a larger coil in series. If you take a resistor and a capacitor in parallel with the speaker, you will find that the resistor regulates how much the capacitor should function exactly like a light bulb and resistor. This is how you will physically experience the effect of a (zobel nettwor) The more advanced explanation is that it also changes the frequency curve of the speakers. Search youtube for it.

[@mariuszsobolewski6713]

It let's the crossover network work as designed, because the impedance of the speakers is stable around the crossover frequency point (ideally at least for 2 octaves).

[@ford1546]

@@mariuszsobolewski6713 I see that many people who make zobel network insert this towards the end of speaker crossover construction. shouldn't zoble be put in almost first and then design the rest of the crossovers around it? If you put in zoble last, the frequency will change too much?

[@mariuszsobolewski6713]

@@ford1546 Zobel Network must be placed right before the speaker driver (in parallel). It doesn't change the frequency response of the driver, only the impedance of it as seen by the crossover network.

[@googoo-gjoob]

wait.....tweeter on top, no radiator. what is this animal?

[@user-od9iz9cv1w]

Again I learn something. Thanks.

[@xyzDonaldxyz]

Is that the FR10 up there?

[@janinapalmer8368]

Paul misled people here I think ... a typical Zobel network consists of a power resistor (10 watts typical) and a BP electrolytic capacitor.. These two components are wired in series and then the two open ends are connected in parallel with the woofer terminals ok 👍. When designed correctly the speakers impedance curve will show a peak in impedance at its fundamental (Fs) frequency and then as the frequency rises it's impedance will remain flat running at or very close to the voice coil resistance ... right up to 20 kHz or more ... The idea of keeping the impedance curve flat is to enable the low pass filter section in the crossover to have its proper effect on the speaker at 8 ohms or 4 ohms . A higher impedance would render the crossover ineffective ... so there you go 😆 KEF used to call this 'Conjugate Load ' back in the 90's ...

[@AmmoDude]

So, would you install a Zobel first, then calculate the crossover at the "flat" impedance level of say, the woofer? Seems a Zobel works to eliminate distortion if speaker impedance rises at frequencies it does not handle well. Sorry for the "layman" terminology, but I am trying to learn this stuff to build my own crossovers.

[@davidstevens7809]

You stsrted with a 12db filter. You could have discussed 6 db filter first. That way the zoebel makes more sense. The problem is.the stored energy smears the signal..everything you add has both positive and negative aspects.

[@bigbirdwpg]

The problem with traditional drivers with voice coils is that they are effectively inductive in nature, making designing a passive crossover very difficult due to the variable nature of the load these drivers present. A properly designed zobel network smooths these reactive loads making them less variable. Then the mathematical formulas for designing the crossover work properly.

[@damaisentosa4631]

12db/octave w/o zobel VS 6db/octave with zobel ....which one is preferable ?

[@stimpy1226]

So that means you added an inductor to make an R-L-C circuit before you circled back to the original R-C circuit? There are many types of these filtering circuits, e.g., a PI filter that are used in DC power supply smoothing, crossover networks and all sorts of electronic circuitry.

[@ronniefranks4351]

I have OCOS speaker cable which is terminated with either a zoebel network or a simple adapter at the speaker end. With my two-way speakers, I used the zoebel adapter. I now own single driver speakers without crossovers. Are there any advantages or disadvantages to using one or the other adapters now that there’s no crossover involved?

[@LeonFleisherFan]

What Paul explained: the driver's voice coil is itself an inductor. A Zobel network is going to smooth out the top end of the rising impedance. This will make a difference in treble response with some amplifiers and not others. Most users of speakers using full-range drivers I know use tube amps. e.g. single-ended. Depending on the quality of the output transformer, the impedance curve of the speaker may influence the frequency response. Best to try and listen if you hear a difference. A Zobel network may also keep some types of solid state amplifiers from being driven into oscillation, but I'd be surprised if, as a full-range user, you owned one of those, as those brands would hardly recommend OCOS cable be used.

[@ronniefranks4351]

@@LeonFleisherFan Thank you for your reply. I use home built Decware 2 watt single-ended amps with Edcor transformers and the speakers are by Omega. The treble rolls off quite rapidly just above 14K. I’m 69 years old so that’s about the range of my hearing anyway. Im guessing from your response that in my case that all the zobel network would do in my case is add a couple more components into the signal path needlessly. What are your thoughts?

[@LeonFleisherFan]

@@ronniefranks4351 Don't you hear a difference in treble extension with the Zobel network in? It's only "unnecessary" if you don't. Love Decware, by the way. But I wonder if you get less treble because of the Edcore output transformers versus Steve's own. Did he give a thumbs up on those?

[@ronniefranks4351]

@@LeonFleisherFan I haven’t had time for listening to sort it out. I want to set up my microphone and measure the frequency response with and without the zobel adapters in addition to just listening. The Edcors are recommended by Steve.

[@LeonFleisherFan]

@@ronniefranks4351 This would be hard to measure from distance. Are the Omega using a whizzer cone? Makes microphone positioning crucial. Lots of cancellation effects with whizzer cones, be sure to toe in aiming at your shoulders in listening position, and at ear height.

[@bikdav]

That explains to me at least.

[@michaelturner4457]

I'd only heard of zobel netowrks been used in telecommunications, to flatten the impedance and improve the bandwidth of analogue transmission lines.

[@digggerrjones7345]

4:07 "Chris can explain it better"

[@trutmaasfull]

Be zobel with your intentions! It probably be better without them…😂🎉 at the end it’s all about to have a great time! 🎶🎶

[@rodrigotudancafernandez17]

Wow.

[@cletusberkeley9441]

I get distracted with all the stuff in the background (speaker lift, absorption material, etc) ....wish Paul used a whiteboard..... I love whiteboards!😂

[@stevesmyth4982]

Yo Paul, how about you use a white board and a market instead of drawing air diagrams? A picture paints a thousand words and all that...

[@randymarko486]

My head hurts ......

[@RoseCare]

First, get yourself confused. Then, confuse the audience to get $4000 for a $100 product. Ah, the classic art of confusion-based sales tactics. Start by creating confusion, then capitalize on it to persuade customers to pay a premium. It's quite the strategy, albeit not the most ethical one.

[@chrisgoodson9312]

I had a terrible feeling that speaker in the background was going to fall on Paul. Some would say "It's how he would have wanted to go"

[@davidfromamerica1871]

Fact.: I am TOO DUMB to be an Audiophile..😀😀😀😀😀 That means I am saved from all the frustrations Audiophiles have with their audio systems and all their cables on a daily basis..🤗👍 Stupid has its rewards.👍😎

[@alex_stanley]

?

[@eldloppa2]

!

[@scottyo64]

$

[@michaelturner4457]

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