Seas A26 Devore Style Build

What surprises me about the seas a26 driver is that it doesn't measure well in the THD department but actually sounds very nice. Im willing to bet it has to do with the lack of xover that would normally interact with the high VC inductance. While this woofer doesn't measure like it, the sound is more pleasant and organic than many 3 way speakers I've heard. The T35C002 is after all my favorite large HF dome.
I dont agree.
the A26 woofer lacks resolution
 
It lacks resolution because its smooth and easy to listen to. I wouldn't say the A26 LF driver is detailed sounding, mainly because it just runs in breakup mode in most of the midrange. That was the reason I said it sounds better than the THD and IMD would suggest. I prefer a good 3 way any day of the week if I'm listening to more resolving material.

I have a pair of A25 clones with the T35C002. Its a nice speaker but its a totally different animal than a typical 3 way monitor.
I dont agree.
the A26 woofer lacks resolution
 
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Actually you did Dave

A26_series_xover_ranshdow.png
 
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1678348636077.png

This is the experimental filter from Håvard at Seas.
A translation of the txt in Norwegian below goes:
“Here is an example of a serial filter I simulated for A26 at the time.
Never tested physically, but looks like it’s working fine. You can put 1uF parallel with R1 to lift the upper octave, but then I would also increase R1 to 10Ohm. C1 can be adjusted to change the level some around 2-4kHz.”
Her er et eksempel på seriefilter jeg simulerte til A26 i sin tid. Aldri testet fysisk, men ser ut til å funke bra. Kan sette på 1uF parallelt med R1 for å løfte den øverste oktaven, men da ville jeg også økt R1 til 10ohm. C1 kan justeres for å endre nivået litt rundt 2-4kHz.
Thanks to Håvard Sollien for allowing me to publish.
 
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Looks like the tweeter and woofer are crossed pretty high at 3500Hz, with no leveling on the tweeter. I'm not sure what making the woofer shunt resistor a high-pass does to the damping, presumably it would have the same effect at resonance as an 8.2 ohm shunt, but less so above the crossover frequency. Seems overall like this crossover makes the woofer more responsible for the midrange, while making the tweeter scream. Cool, I may have to try this some day.
 
We actually measured your filter in an A-35 enclosure at the Seas anechoic chamber a while back and it's got a slightly falling response. Hate to sound like a broken record but I need to dig out the Klippel files and re-format them to post. Maybe over the weekend.

edit:

Found it, here's the 0 axis
1678395959873.png
 
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Haha, how cool! The A26 / series xover do sound prominent in the midbass, which is something I like, and especially with streamed jazz.

(Also I take back my earlier comment- I'm not sure the 8.2 ohm resistor would do much at all at the woofer resonance, it's blocked by a capacitor at LF.)
 
I simmed a crossover of an own variation of a A26 i'm planning, but with a different tweeter, and came to something very similar as Planet10 actually
1678431504340.png
It has not been tested in reality, but it looks good. The Speaker will be a 2 way MLTL with a SB26ADC tweeter and the A26RE4 woofer, and build can take a while as i have some projects lined up in advance to be done... But it seems that with the natural rolloff of that woofer, it's very easy to use in a good 1st order crossover, serial or pârallel, both work well.
 
thanx, How does this look?

View attachment 1151452

dave
Doesn't this network create 2nd order slopes in the drivers? Having the RC on the woofer along with the coil (acting as a cap in series alone) appears to change the tweeter rolloff to some extent compared to just a cap in series with the tweeter. What does a sim look like as a comparison and does the series xover defeat the goal of having a phase correct xover?
 
There is something called zeta in sxo filters, mainly 1st order types. A quasi-12dB zeta style exists, which halves the impedance at the xover point. IIRC, it has to do with the ratio of the components.

I don't use the zeta methods, and model the xover when I use an sxo. So, I am not as well versed in those methods. What you see in the schematic is a 1st order on both sides electrically.
 
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