i am using 2 4ohm dynaudio 17w75xl drivers in series for a 2 way speaker.
david morison helped me before i tried using winisd. and came up with 10L for closed box volume for 17w75xl
it's a flat curve . id like a little steeper slope so tried smaller volume to boost upper bass frequencies
i am using iso-barik setting on winisd to model the output.
so when using one 4ohm 17w75xl driver in 6 L box I get the same plot
as when using two 4ohm 17w75xl drivers in 3L box. i understand 4ohm driver is more efficient than two 4 ohm paired into an 8ohm.
but shouldn't the box for 2 driver be twice the size of a box for one driver?
so shouldnt two 17w75xl connected in series require a 12L box as opposed to a 3L box
whats the error?
i attached images of winisd results
green graph is a graph of 8ohm polk mw6503 driver i am looking to replace with 2 17w75xl drivers
blue graph is one 17w75xl 4ohm in 7L box(if i put 6L volume it overlaps with 3L graph )
yellow is two 17w75xl 4ohm in series in a 3L box
david morison helped me before i tried using winisd. and came up with 10L for closed box volume for 17w75xl
it's a flat curve . id like a little steeper slope so tried smaller volume to boost upper bass frequencies
i am using iso-barik setting on winisd to model the output.
so when using one 4ohm 17w75xl driver in 6 L box I get the same plot
as when using two 4ohm 17w75xl drivers in 3L box. i understand 4ohm driver is more efficient than two 4 ohm paired into an 8ohm.
but shouldn't the box for 2 driver be twice the size of a box for one driver?
so shouldnt two 17w75xl connected in series require a 12L box as opposed to a 3L box
whats the error?
i attached images of winisd results
green graph is a graph of 8ohm polk mw6503 driver i am looking to replace with 2 17w75xl drivers
blue graph is one 17w75xl 4ohm in 7L box(if i put 6L volume it overlaps with 3L graph )
yellow is two 17w75xl 4ohm in series in a 3L box
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17w75xl data sheet
http://site.diy-loudspeakers.com/im...peakers/dynaudio/WOOFERS/DYNAUDIO_17W75XL.pdf
driver is designed for vented operation. but closed 3L just sounds like a very small volume
same thing with vented operation
2 drivers in series require half the volume of one driver
http://site.diy-loudspeakers.com/im...peakers/dynaudio/WOOFERS/DYNAUDIO_17W75XL.pdf
driver is designed for vented operation. but closed 3L just sounds like a very small volume
same thing with vented operation
2 drivers in series require half the volume of one driver
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Oops yes)
Then how to model 2 identical 4ohm speakers in series in winisd in closed box or vented box
Then how to model 2 identical 4ohm speakers in series in winisd in closed box or vented box
2 drivers in the same box require 2x the driver. If in an isobarik configuration the base volume of the box is hlf that of 2 drivers. But with a small box the overhead of the coupling chamber wipes out any gross volume if the box. Isobarik gives no more sensitivity, but requires more power (used to make a half size box work).
Isobarik should not be used above low frequencies.
Doesn’t matter id it is series or parallel wired.
dave
Thank you I started reading on isobaric design using regular midrbass drivers. Looks like its an.outdated practice and for subwoofers only
Does winisd treat "normal" setting as drivers connected in parallel or in series. Just trying to figure out which settings to use to model vented and closed volumes for these pair of drivers connected in series
Isobarik arose in the eraly days because the selection of diy woofers available was small, and a compund driver could be used to get the extention required in a smaller box.
The limit of the HF is based on the half-wave distance between the front driver and the back. At some point the wavelengths get short enuff that the reflection starts causing ripple in frequencies above that distance base criteria.
Nowdays you just dig deeper into the product catalogs and find a woofer that does not need help to hve a smaller box size.
dave
The limit of the HF is based on the half-wave distance between the front driver and the back. At some point the wavelengths get short enuff that the reflection starts causing ripple in frequencies above that distance base criteria.
Nowdays you just dig deeper into the product catalogs and find a woofer that does not need help to hve a smaller box size.
dave
As far as box volume and tuning are concerned, it pretty much doesn't matter whether you think of it as being in series or parallel. The acoustic results will be the same whichever way they're wired, as long as each driver has the same voltage applied to it.
The parts where it matters are in designing the crossover (if passive), sizing your amp to drive the load and setting gain structure to match levels with other passbands.
Remember that regardless of the number of woofers specified, the impedance curve shown in WinISD is for each individual driver.
The parts where it matters are in designing the crossover (if passive), sizing your amp to drive the load and setting gain structure to match levels with other passbands.
Remember that regardless of the number of woofers specified, the impedance curve shown in WinISD is for each individual driver.
Re:'Then how to model 2 identical 4ohm speakers"
Remember post #14 in this thread?:
.https://www.diyaudio.com/community/threads/replacing-an-8-ohm-driver-with-two-4ohm-drivers.380740/
Remember post #14 in this thread?:
.https://www.diyaudio.com/community/threads/replacing-an-8-ohm-driver-with-two-4ohm-drivers.380740/
Reading through that interesting article..but isn't the guy talking about parallel connection of 2 different drivers in same box. This thread is probably circling back to the other thread where I asked about 2 4ohm identical drivers in series (not parallel). I didn't read the whole article that petemck shared because It talked about parallel connection of two different drivers. But let me finish the article .
Basically was hoping to find answers in this format
User rosarian from audioholics forums
"
These Thiele/Small parameters are not affected by using multiple drivers:
Fs, Qes, Qms, Qts, Xmax
These are increased for each additional driver:
Vas, Pe, Sd
so that 2 drivers doubles the values, 3 drivers triples the values, etc.
Sensitivity is affected differently. Putting 2 drivers in series has no effect, but putting 2 drivers in parallel adds 3 dB to the value."
Or in this thread
https://www.diyaudio.com/community/threads/thiele-small-parameters-for-2-drivers-in-series.297199/
User rosarian from audioholics forums
"
These Thiele/Small parameters are not affected by using multiple drivers:
Fs, Qes, Qms, Qts, Xmax
These are increased for each additional driver:
Vas, Pe, Sd
so that 2 drivers doubles the values, 3 drivers triples the values, etc.
Sensitivity is affected differently. Putting 2 drivers in series has no effect, but putting 2 drivers in parallel adds 3 dB to the value."
Or in this thread
https://www.diyaudio.com/community/threads/thiele-small-parameters-for-2-drivers-in-series.297199/
Looks like you've gotten what you wanted, so all I can think of to add ATM is that if it takes a 0.5xSd vent area (Av) for one driver to meet the max acceptable vent mach, then it either takes two vents or a 1.0xSd for dual drivers with one vent, so if the single is 1" dia., then the single big one needs to be at least a 1.0*sqrt(2) = 1.4142" dia..
Inductance (Le) sums in series and divides in parallel, so if using over a wide BW, then in series it may roll off the HF BW enough above its upper mass corner (Fhm) enough to impact XO point/slope for flattest response.
Fhm = 2*Fs/Qts'
[Qts']: [Qts] + any added series resistance [Rs]: http://www.mh-audio.nl/Calculators/newqts.html
[Rs] = 0.5 ohm minimum for wiring, so may be higher if a super small gauge is used as a series resistor plus any added resistance from an XO/whatever.
Inductance (Le) sums in series and divides in parallel, so if using over a wide BW, then in series it may roll off the HF BW enough above its upper mass corner (Fhm) enough to impact XO point/slope for flattest response.
Fhm = 2*Fs/Qts'
[Qts']: [Qts] + any added series resistance [Rs]: http://www.mh-audio.nl/Calculators/newqts.html
[Rs] = 0.5 ohm minimum for wiring, so may be higher if a super small gauge is used as a series resistor plus any added resistance from an XO/whatever.