[eunice]

This one?
https://diyaudioprojects.com/Technical/Speaker-Zobel/

This is the exact formula, but you had a rule of thumb if we do not know voice coil inductance, which we don’t for knowles GV. We only have impedance.

 

[Ivan TT]

This is the exact formula, but you had a rule of thumb if we do not know voice coil inductance, which we don’t for knowles GV. We only have impedance.

HODVTEC's one is known (7.9mH), assuming same value for TWFK (or each driver) 0.47-1uF is a good starting point.
But I would try going higher (4.7-10uF) as higher capacitance seem to improve bass and provides less colouration (especially if resistor value is overshot by another 20-25%).
I don't really believe zobel for BAs should be based on formula (unless it's a starting point), tuning by the ear and alternatively using LIMP (although I did not like the straightest impedance curve I could get by adjusting resistance/capacitance) give better results.
PS: sorry, I don't have GV and will be getting it at some stage, but not too soon.

 

[IvanNOON]

Please, I think the point is made sufficiently clear, we are all not professionals and we are all trying to learn.

Sorry if I went a little overboard, I got a wrong impression that @dhruvmeena96 didn't understand such a basic thing.

Wires do have a resistance, signals do take time to travel through a wire, wire loops do create an inductance.

IMO such things are negligible for our projects

 

[Ivan TT]

And this is how I would solder it for 2-pin

Spoiler: Photo

I did just that using mmcx connector and actually would not recommend it: too easy to overheat socket and too tricky to get it tidy.
Best approach that works for me now is to solder 0805 SMDs together, seal with Bondic, solder to estron wires some place between socket and drivers, seal solder points with Bondic again, glue up to the shell. Going to try same approach on crossovers soon, have few well overdue multi-driver configurations to build

 

[eunice]

HODVTEC's one is known (7.9mH), assuming same value for TWFK (or each driver) 0.47-1uF is a good starting point.
But I would try going higher (4.7-10uF) as higher capacitance seem to improve bass and provides less colouration (especially if resistor value is overshot by another 20-25%).
I don't really believe zobel for BAs should be based on formula (unless it's a starting point), tuning by the ear and alternatively using LIMP (although I did not like the straightest impedance curve I could get by adjusting resistance/capacitance) give better results.
PS: sorry, I don't have GV and will be getting it at some stage, but not too soon.

Thank you so much. I know from what you have told that we need to tune by ear. But having a reasonable starting point helps a lot for experimenting.

So you would chose the resistor to be the impedance @500Hz (wich is 50 Ohms) and the cap to be 4.7uF-10uF as a start value for experimenting ?

 

[eunice]

Regarding wire inductance/resistance:

IMO such things are negligible for our projects

I do think so too. But remember, we are on an audiophile forum, think about that next time you de magnetize your CDs.

 

[IvanNOON]

Regarding wire inductance/resistance:

I do think so too. But remember, we are on an audiophile forum, think about that next time you de magnetize your CDs.

We are on an audiophile forum, that's why I burn-in my litz wires for at least 300hours before I build anything
/s

 

[Ivan TT]

So you would chose the resistor to be the impedance @500Hz (wich is 50 Ohms) and the cap to be 4.7uF-10uF as a start value for experimenting ?

Anywhere between 50 and 64 Ohm as a starting point, yes.
Cap - 1uF as per hypothesized inductance of GV, but would also be planning to overshoot it up to 10uF.

Spoiler

I feel a bit bad about not having GVs to do the tuning on them similar to BS6's (but I have an excuse - it was either GVs or taking kids to Billie Eilish, the choice was rather obvious), but a friendly awesome head-fi'er may loan me a pair of GVs soon - stay tuned

 

[dhruvmeena96]

HODVTEC's one is known (7.9mH), assuming same value for TWFK (or each driver) 0.47-1uF is a good starting point.
But I would try going higher (4.7-10uF) as higher capacitance seem to improve bass and provides less colouration (especially if resistor value is overshot by another 20-25%).
I don't really believe zobel for BAs should be based on formula (unless it's a starting point), tuning by the ear and alternatively using LIMP (although I did not like the straightest impedance curve I could get by adjusting resistance/capacitance) give better results.
PS: sorry, I don't have GV and will be getting it at some stage, but not too soon.

The important part is to get phase linear, the impedance to be flatten enough that it doesnt have unwanted peak and rising inductance impedance in treble

 

[Choy Wei De]

The important part is to get phase linear, the impedance to be flatten enough that it doesnt have unwanted peak and rising inductance impedance in treble

Possible to come with a middle ground there the Zobel value that works for both RAB and GQ?

 

[dhruvmeena96]

Please, I think the point is made sufficiently clear, we are all not professionals and we are all trying to learn. Wires do have a resistance, signals do take time to travel through a wire, wire loops do create an inductance.

But we are among audiophiles here, we should trust our ears.


Does anyone remember how @Ivan TT would calculate the Zobel for a Knowles GV? He had a nice formula for starting values.

Wire have negligible resistance, well... Well, linear electrical phase takes care of timing issues pretty much on single driver setups.
On multi driver, if acoustic phase is corrected, then everything would sound on time.


Well you shouldn't expect source perfect time.

Plus, I don't remember the exact software, I think rockbox also had a feature for correcting time

Well media player classic has reclock addon(which doesnt work with win10 now)

You have to buffer music into RAM and then according to wire resistance average, you have to reclock the signal speed to get source perfect sound.

Because wires and cable have a law of diminishing result

OFC vs OCC copper has difference of 2% in overall signal improvement(which is neglibile)

So wire resistance, and signal resistance is a topic where we won't go to a positive end


Inductance and capacitance are unmeasurably low on common wire..

If it is bad wire(very bad) then you have to think about it

 

[dhruvmeena96]

Possible to come with a middle ground there the Zobel value that works for both RAB and GQ?

No need, RAB near flat impedance when paralleled with GQ, gives more of a linear looking impedance

 

[ForceMajeure]

Anywhere between 50 and 64 Ohm as a starting point, yes.
Cap - 1uF as per hypothesized inductance of GV, but would also be planning to overshoot it up to 10uF.

Spoiler

I feel a bit bad about not having GVs to do the tuning on them similar to BS6's (but I have an excuse - it was either GVs or taking kids to Billie Eilish, the choice was rather obvious), but a friendly awesome head-fi'er may loan me a pair of GVs soon - stay tuned

How does Billie Eilish sound on your iems though

 

[Ivan TT]

How does Billie Eilish sound on your iems though

Sounds quite good, actually - especially on BS6, to goosebumps level.
And blessedly no screaming teenagers (my SPL meter measured about 107dB level during the gig, BETWEEN songs).

 

[dhruvmeena96]

HODVTEC's one is known (7.9mH), assuming same value for TWFK (or each driver) 0.47-1uF is a good starting point.
But I would try going higher (4.7-10uF) as higher capacitance seem to improve bass and provides less colouration (especially if resistor value is overshot by another 20-25%).
I don't really believe zobel for BAs should be based on formula (unless it's a starting point), tuning by the ear and alternatively using LIMP (although I did not like the straightest impedance curve I could get by adjusting resistance/capacitance) give better results.
PS: sorry, I don't have GV and will be getting it at some stage, but not too soon.

Based on formula is for single driver or a setup of same drivers.

Multi driver I hard to predict and I agree with @Ivan TT .
LIMP and ears are more important