Best design for mostly TV/movies?: XT25SC90 NE123-8 NE180-8 -- Wavecor TW300WA14 NE180-8 -- NE123-8 26W/8861T --

[Jimmy154]

Leaning towards first design, but it's pretty complex.
The Wavecor TW030WA14 NE180-8 (2.5-way) seems easiest, but I read the NE123 is more or less magical.

Tymphany NE123-8 and Scan-Speak Revelator 26W/8861T00 Bass-mid woofer would be easiest
I also have some TG9, TC9 fullrange drivers.
Also have ScanSpeak neo tweeter

Tymphany XT25SC90 NE123-8 NE180-8 NE180-8 -- I think will have to be MTWW --
Wavecor TW030WA14 NE180-8 NE180-8 -- would be easier, but I'm not sure voices would be as good.

https://hificompass.com/en/speakers/measurements/vifa/vifa-ne123w-08
https://www.dibirama.it/home-page/tweeter/340-wavecor-tw030wa14-tweeter-1-1-4-8-ohm-70-wmax.html

 

[Jimmy154]

Was going to build the 2.5 way:
Wavecor TW030WA14 tweeter and 2 NE180W
But I seem to be having phase shift issues.
Cancelation above the cross-over frequency and then if I invert the tweeter, at the cross-over frequency.
How can I fix the cross-over?

 

[weltersys]

How can I fix the cross-over?

Inverting polarity results in a 180 phase shift, which only "fixes" the phase/frequency response if the acoustic crossover is 12dB per octave.
Looks like the acoustic crossover slopes are closer to 6dB per octave than 12dB per octave, the woofers only drop ~-13dB between 1 kHz and 4kHz, probably due to the woofer's +4 to +9dB peaking response between 2-6kHz.
You might try LR rather than BW slopes, and/or a notch filter on the woofers, or whatever required to get the acoustic slopes closer to second order.

Also, L4, R2 and C4 don't appear to be terminated, which in real life would make quite a difference in the crossover order 😉

 

[Jimmy154]

Yes, it's not terminated on puerpose.
The crossover looks okay at 0 acoustic offset. But at 1.5 or .7 inch it's not good.
Attached is mod delay 0 and also added a cap to the lower woofer, that doesn't seem to matter much.

 

[temp25]

Try adding a resistor in series with L1. Start with about 2 ohms, and then increase.

 

[weltersys]

Attached is mod delay 0 and also added a cap to the lower woofer, that doesn't seem to matter much.

180 degree of phase change is what you should see over the passband of a speaker using a second order crossover:

Looks okay to me.

 

[Jimmy154]

Yes, x-over is fine at mod delay 0, BUT not fine with mod delay -0.7-1.5 inch on the woofers where they sit on the baffle or .75 infront of the tweeter.
I could just put the tweeter 1.5" behind the woofer, but that would look weird. So I'm trying to fix it with the cross-over.
In the 3-way design it was fixed with a 0.7-1" removable baffle for the woofers and tweeter "sits flat" on the speakers.
Resistor in series with L1 did not help.
Pic attached.

 

[Jimmy154]

Down to 2 designs I think.
It's funny how I've only liked 2 tweeters I've heard.
XT25BG60 and Wavecor tweeters in general.
Even the XT25SC90 (neo version) doesn't sound that great.
Actually forgot about AMT tweeters, they also sound great.

Seems like I can get rid of the 18 uF cap on the tweeter in the 3-way and have a deep inverse null between the XT25 and NE123, but I'm not sure how important that is.

Mod delay is 0 with all these. Seems like I will have to do something with the baffles.

 

[temp25]

Do you know how to make a tank filter?

Looking at the woofer roll-off, and it's not very steep. Your tweeter looks to have a 4th order. The woofer is far from 4th.

How far from the speaker will you sit? What distance are you measuring from?

 

[Jimmy154]

I have this design too.
I like the build quality of the Satori.
Wavecor probably sounds the best, then the neo XT25SC90.
Wavecor and large XT25BG60 actually sound similar too me, but Wavecor has way more lower end.

Something tells me the 2.5-way might sound better than the 3-way.

3-way or 2.5-way for TV mostly? I'll be sitting about 3 meters away.

 

[Jimmy154]

3-way or 2.5-way for TV mostly?

 

[temp25]

A 3-way will give you the better flexibility to voice the speaker, so without even looking at your previous posts, I'd say 3-way.

 

[temp25]

I've been on a center channel rampage lately. Voicing is critical to my ear. The shows themselves are not perfect, but location in the room changes the requirements. I'm pretty much finished with my recent center. It's a 10" 2-way. Distortion is very low.

 

[Jimmy154]

alright I think I get it -- any one else:
3-way or 2.5-way for TV mostly?

 

[Lojzek]

Would you attach the whole project file of the 2.5 TMM?
Measured or traced responses?

 

[Jimmy154]

That's all I have. Traced, manufacture's and other persons' measurements.
For Peerless XT25 there are many measurements online.
Also a lot for the other drivers.
https://ampslab-spk.com/2020/12/04/rosefinch/

 

[Lojzek]

I thought I'd give it a look at the x/o filter, but I can't do that if you won't upload .dxo file.

 

[Jimmy154]

ok thank you. I attached some dxo files. Filters are in pics also.

 

[Lojzek]

All of the drivers lack phase data (2.5 TMM), both frd and zma. Tune the driver frd and zma by checking the derived box
and define the FR tails. NE 180 is not exactly an easy drive unit to work with. It'll need a steeper filter, likely.