array of micro speakers with shading in ATH4 horn

[limacon]

small bump at 2.5k, other wise seems good!

 

[kipman725]

I notice you round the corners of your speaker in simulation is this just how the speaker is to be constructed, a delibrate nod to diffraction or to reduce simulation artifacts? (or some combination)

 

[limacon]

All of the above.

 

[limacon]

wedge improving response

 

[limacon]

Some minor changes to improve response.

2k DI bump is annoying me.

Maybe bounce from the top and bottom surfaces?

 

[limacon]

Flat at 30deg

 

[limacon]

Smoothed out the bump in DI. Cabinet shape tweaks to smooth out off axis axis a little better. At the expense of some 15k+ craziness. Will reveiw my mesh settings again.

 

[limacon]

Horizontal, 200-15k, normalised to 0deg.

 

[rexwagner]

Today I designed a dev board for an old PWM dsp from D2 Audio / now Renesas.

https://www.renesas.com/us/en/produ...lligent-digital-amplifier-and-sound-processor

I have 12 channels of PWM high & low buffered output (SN74LVC2G34) at 5.5V. SNR>110dB & THD+N <0.01% .

• 2 x I2S input
• 2 x SPDIF input
• 1 x SPDIF output
• protection inputs
• 90mm x 120mm

MCU for initial programming to the dsp memory plus volume & tilt pot.

In theory I could use the PWM high & low buffered outputs as speaker low output test drivers (25ma) with suitable filtering.

View attachment 1109614 View attachment 1109616

Nice !
My d2-92633-lr broke down a long time ago, so I'm very interested in your dev board.
Would you mind sharing more info on it ?

 

[limacon]

I made a board exposing all I/O. I use it for testing various power stages.

There are no power stages on board, just 5.5V level complementary PWM for up to 12ch.

What info would you like to know?

 

[rexwagner]

Congrats, nice project.
Well I'd love your PCB layout so I could adapt it to my needs, and then build it.
Are these small aligned things on the other board loudspeakers ? How high can they go in frequency ?

 

[stocktrader200]

What are the speakers you are using?
Why not put the in multiple series config 4 × 32 ohms for 8 ohms and use a 50 w amp?

 

[limacon]

doing that too!

 

[stocktrader200]

5 x 8 for 40 speakers at 8 ohms.
Love to see how it performs.

 

[TNT]

How are these coming along?

//

 

[limacon]

Like many of my projects, slowly!

 

[TNT]

OK! All in due time

//