Reply To: Dayton KABD + Sigma Studio

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#24524
AJC
Participant

I’m going to make it for the JAB5 to start. Then modify it as needed for other sigmastudio devices as time goes on. The design portion is the same, but the hardware settings varies and shouldn’t be fussed with for the most part (due to risk of making something give up the smoke).

But I’ll explain going through to do impulse response in REW and how to step that in sigmastudio to get it aligned. Once aligned, how to use the mute function to mute one drive or the other to get a clean reading on volume (also because those will matter for figuring out the first point to start doing a crossover). After you have volume leveled, I recommend to start over and check the impulse response again and then check the volume again if impulse response was adjusted. Then it is picking the crossover point and doing iteration on selecting the right point and trying to prevent any aberrations. From there, you can do the setting of the high pass on the low end of the woofer or sub. That is a balancing of trying to get a lower frequency, but also to prevent low end excursion and distortion (if you prevent it getting close to x-max, then the driver will act more linear, which can help reduce distortion, which in turn can help with compression issues when playing louder, etc.). If doing a 2-channel bookshelf or if you have an external sub, you can just set the low end to where you are crossing over and so long as that is not at x-max, you are done (like an 80-120Hz high pass). After that, I move to setting up the PEQ filters, which should in theory be straightforward.

After you have done all of that, things that can be removed are any mute buttons (you cannot use them outside sigmastudio anyways, so when finishing it to close everything into the enclosure, you do not need that anymore), any invert buttons unused (mainly there for convenience in the event you wired it backwards so you don’t have to fix that), probably the gain for the lowest dB driver, the time alignment of the largest driver that is furthest away from the tweeter (unless a special case where you couldn’t get it aligned, so you adjust all looking for a common subdivision to get all drivers maximally aligned). Also explain the left and right and to mark the speakers so that you don’t confuse which speaker is getting which channel.

From there, it is flashing it with slowly increasing the number of taps on the FIR filter (I start with 50s, then 20s, then 10s). Once you know how many you can add, you put that number in RePhase, then tell it to try to create a flat phase. Whatever it kicks out, you move that over to sigmastudio (there is a text file thing on formatting, but I forgot the details at the moment).

Then, it is putting it in your room, using masking tape to mark out placement as you may have to move the speaker to access sigmastudio again. You do the impulse response again for left and right channels from the listening area. Once you determine which driver is off on the delay, add that delay to get the impulse response aligned. And, finally, volume level both speakers with the last gain setting in the schematic to get the speakers playing at the same sensitivity.

Viola! That should give you roughly the best experience you could get with an ADAU1701.

@elliottdesigns @123toid