[Low distortion]

Great example here of the dispersion pattern possible when the acoustic centres of the drivers are aligned.

https://www.alconsaudio.com/product/qr24/




This design style results in a perfectly even sound from all positions in the room. Massively huge sweet spot.

[Danny Richie]

A unique solution to the comb filtering issue would be to mount LT2 tweeters in the center of each LT10 with a special bracket, and time align them with DSP. This way the acoustic centres would be 0” apart. The baffle could be much skinnier as well.

That actually doesn't work very well. It really disrupts the response from the surface and edge diffraction.

There is also no way I would produce a speaker of this level with DSP in the signal path.

Mounting then side by side aligns the playing surfaces and gives them great time arrival. So in this regard they are already great.

[Low distortion]

Alcons pulled it off pretty good. DSP is required for the best sound these days. Just can’t use crappy DSP.

[Danny Richie]

Great example here of the dispersion pattern possible when the acoustic centres of the drivers are aligned.

https://www.alconsaudio.com/product/qr24/




This design style results in a perfectly even sound from all positions in the room. Massively huge sweet spot.

I've heard those. Well, they were capable of playing loud. That was about it.

[Low distortion]

So do you think that dispersion pattern is undesirable in a speaker? That’s an active speaker with mediocre electronics. So the sound quality is likely limited by the electronics.

[Danny Richie]

Alcons pulled it off pretty good. DSP is required for the best sound these days. Just can’t use crappy DSP.

The best playback systems are not digital. Vinyl, as a playback medium, is by far still the king when it comes to best sound, and no one is going to digitized their vinyl.

[Low distortion]

Well that may be the opinion of 0.00001% of the population. And everyone is open to have their own opinion.

[Danny Richie]

So do you think that dispersion pattern is undesirable in a speaker? That’s an active speaker with mediocre electronics. So the sound quality is likely limited by the electronics.

We always look at dispersion in both horizontal and vertical planes with everything we work on. An even and consistent response in all directions is important to maintain an even overall room response.

[Low distortion]

We always look at dispersion in both horizontal and vertical planes with everything we work on. An even and consistent response in all directions is important to maintain an even overall room response.

Do you have the same style of polar plot I shared from the Alcons for the Line Forces?

[Danny Richie]

Well that may be the opinion of 0.00001% of the population. And everyone is open to have their own opinion.

My digital playback system is on the the best I've ever heard. It sounds very musical and very analog sounding compared to even some of the most favored digital playback systems. It is still a long way from the best vinyl systems.

[Danny Richie]

Do you have the same plot I shared from the Alcons for the Line Forces?

That isn't an industry standard measurement. It is an illustration.

[Low distortion]

That isn't an industry standard measurement. It is an illustration.

Ok then any polar plots.

[Low distortion]

I think if we were to study the polar plots we would discover why Jaytor is experiencing a tiny sweet spot with his line forces.

[Danny Richie]

Ok then any polar plots.

I look at and measure them in both directions. Because the center to center spacing is so small and the crossover point is so low then there is only a difference in the off axis in the top end as the tweeter (like all tweeters) drops out in the off axis. There is little to no change from the time alignment of the drivers.

[Danny Richie]

I think if we were to study the polar plots we would discover why Jaytor is experiencing a tiny sweet spot with his line forces.

The change he is referring to is the change vertically. The line is only five feet long. So in order to maintain a consistent and accurate sound then the listener needs to stay near the center of the line.

[Low distortion]

I look at and measure them in both directions. Because the center to center spacing is so small and the crossover point is so low then there is only a difference in the off axis in the top end as the tweeter (like all tweeters) drops out in the off axis. There is little to no change from the time alignment of the drivers.

 What’s wrong with measuring the polar response and sharing the results? It’s become industry standard to do that these days. Especially with expensive speakers. Sure I agree it’s possible to have a great polar response and still bad sound. But a great speaker, with great drivers, great crossover design and well constructed cabinets will only sound better all over the room if the polar response is stellar.

[Low distortion]

The change he is referring to is the change vertically. The line is only five feet long. So in order to maintain a consistent and accurate sound then the listener needs to stay near the center of the line.

This is what I read:

“ I haven't done a lot of placement tweaking yet, but one thing I am not completely satisfied with at this point is the sweet spot width. Compared to the NX-Oticas, the sweet spot seems to be considerably narrower. If I move more than a foot or so from center position, it sounds like I'm only hearing the closer speaker.”

Sounds like lobing issues to me.

[david45]

Another important factor to consider is acoustic center spacing. This is going to be about 4.5" apart in a horizontal plane. That is a wavelength of about 3kHz. So the crossover point has to be (by rule of thumb) below 3kHz to avoid any significant comb filtering in the horizontal plane. With a crossover near 1kHz (piece of cake) then you can move horizontally in either direction without the change in time arrival having any real effect on the response.

If the crossover were pushed up into the 4khz region then any movement left or right would create enough of a phase rotation to start causing some comb filtering. So anything beyond 20 degrees or so would result is significant holes in the response to the tune of up to 15db.
So the lower crossover points are a MUST.

Thank you for chiming in, Danny.

[david45]

This is what I read:

“ I haven't done a lot of placement tweaking yet, but one thing I am not completely satisfied with at this point is the sweet spot width. Compared to the NX-Oticas, the sweet spot seems to be considerably narrower. If I move more than a foot or so from center position, it sounds like I'm only hearing the closer speaker.”

Sounds like lobing issues to me.

Jaytor,

Would you care to comment on your observations regarding the size of the sweet spot with the Line Forces vs your NX-Oticas now that your big caps are properly broken in? Is it still an issue you feel the need to work on?

[david45]

The change he is referring to is the change vertically. The line is only five feet long. So in order to maintain a consistent and accurate sound then the listener needs to stay near the center of the line.

Danny,

I was under the impression that the response would be similar pretty much along the full length of the line array considering we are only getting the output equivalent to a single Neo10 and Neo3 at any position.

But then again I can’t imagine they are unlistenable when standing up either… and most likely Jaytor’s guests won’t even notice?