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Built in DSP options for DIY active speakers?

Emilime75

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New here, and hoping this is the right place for the question.

TLDR; I am looking for small, affordable and high quality DSP options that can be installed within a speaker enclosure to serve as the processor for an active speaker, could be anything from a 2 way to a 4 way. I'm already familiar with things like Sure/Wondom, MiniDSP, T.Racks... But, wondering if there was something else I haven't come across. My wish list is the following;
  1. No case needed as it will be built into a speaker enclosure and keep cost down
  2. Digital input preferred - USB, coaxial, optical and/or BT. My main use case would be USB as preferred as both audio signal transmission and setup over 1 cable. 2nd would be coaxial/optical and if both had a BT option, that would be great
  3. Can be modular, as in DSP board is separate from I/O... Might actually be preferred for packaging within the enclosure
  4. GUI for setup
  5. Better spec/sound quality than Sure/Wondom, MiniDSP, T.racks...

Long version; I like to build speakers and I like them active, I also work in the commercial AV integration industry. With that, I've become quite familiar with boxed DSPs and have used various products from MiniDSP to QSC Q-SYS Core/s and a slew of others in-between. Currently running a BiAmp Tesira Server powering my main HT/Music system with a dedicated DSP/amp channel for each driver in the system, totaling 22 channels. This has been fine over the years and in dedicated rooms where I can have racks of gear, it's been a lot of fun.

Fast forward to today, I'm getting older and tired of huge racks and want to start integrating both the processing and amplification into the speakers I build. I also want to build some small/er systems for use on desktops and such. I could still do this with the DSPs I've been using and just run multi conductor line level cable to each speaker cabinet, but I'd prefer to make them more self contained and if I ever want to use the speakers elsewhere, everything needed comes with them.

The 2 speaker plans I currently have in mind that will need DSP are a pair of 3.5 way near field monitors for my computer desk and a 2.5 or 3 way sound bar for a 2nd computer desk. So I'll need 7 channels total for the 3.5 way, and 5-6 for the 2nd build. This gets really clumsy with the products I am currently aware of.

Looking forward to hearing your suggestions.
 
Hypex FusionAmp line - 1 to 3 channels of nCore amplification plus DSP on a plate. You can try their management software without needing the amps.
3E Audio's ADAU1701 board was measured here - perhaps a small step up from the bare Sure/Wondom board, but not much.
I always hoped to see measurements for the Auverdion Aurora, but I don't think it's been available since the AKM fire.
 
Hypex FusionAmp line - 1 to 3 channels of nCore amplification plus DSP on a plate. You can try their management software without needing the amps.
3E Audio's ADAU1701 board was measured here - perhaps a small step up from the bare Sure/Wondom board, but not much.
I always hoped to see measurements for the Auverdion Aurora, but I don't think it's been available since the AKM fire.
Agreed!
 
Hypex FusionAmp line - 1 to 3 channels of nCore amplification plus DSP on a plate. You can try their management software without needing the amps.
3E Audio's ADAU1701 board was measured here - perhaps a small step up from the bare Sure/Wondom board, but not much.
I always hoped to see measurements for the Auverdion Aurora, but I don't think it's been available since the AKM fire.
Sorry, should have stated I already have stacks of IcePower amps and would rather use them.
 
Sorry, should have stated I already have stacks of IcePower amps and would rather use them.
Not sure what those are that you have, but ICE makes dsp boards for their amps similar to what Hypex does for a few of their amp modules.
 
I used the Digmoda IcePower solutions years ago to tri-amp a pair of Apogee Scintilla.

 
Not sure what those are that you have, but ICE makes dsp boards for their amps similar to what Hypex does for a few of their amp modules.
Can you point me to them? Haven't heard of this before and a quick Google search doesn't yield anything - except for aftermarket plate amps like the PWR-ICE 125 and 250 that integrate an IcePower amp with MiniDSP processing.
 
 
There are also the somewhat questionable DSP boards from Parts Express. I've a feeling your looking for something a little better though.
 
Might be worth looking at some of the car audio DSP boards as well.
 
New here, and hoping this is the right place for the question.

TLDR; I am looking for small, affordable and high quality DSP options that can be installed within a speaker enclosure to serve as the processor for an active speaker, could be anything from a 2 way to a 4 way. I'm already familiar with things like Sure/Wondom, MiniDSP, T.Racks... But, wondering if there was something else I haven't come across. My wish list is the following;
  1. No case needed as it will be built into a speaker enclosure and keep cost down
  2. Digital input preferred - USB, coaxial, optical and/or BT. My main use case would be USB as preferred as both audio signal transmission and setup over 1 cable. 2nd would be coaxial/optical and if both had a BT option, that would be great
  3. Can be modular, as in DSP board is separate from I/O... Might actually be preferred for packaging within the enclosure
  4. GUI for setup
  5. Better spec/sound quality than Sure/Wondom, MiniDSP, T.racks...
<snip>

Looking forward to hearing your suggestions.
Hi Emilime75

I'm using the ESP32-S3 as DSP. For $1,00 you get tripple 32bit cores - one 20MHz low power and two 240MHz high speed cores with floating point, DSP and vector processor acceleration. It also has built in wireless WiFi & BT 5.0 radio on-chip for direct digital audio streaming. I use TI class-D amplifiers with I²S digital audio interface and I²C configuration interface. This way there's no ADC and the DAC is in the class-D amp.

The amp depends on how much power you need. In my current project I'm using the TAS5828M that delivers 2x50W@4ohm, 100W@2ohm or 80W@3ohm. It's listed at $1,87 on Digikey. I use one amp per two speakers to avoid analog cross overs. The ESP32-S3 has two stereo I²S interfaces so you can run 4 speaker outputs in parallel. Bigger versions are available on the TI website if you need more power.

For quick prototyping I'm using the t.rack DSP 4x4 Mini Amp with built in 4x50W amps and power supply. It's quite cheap, compact and good enough for prototyping. Prototype enclosures are 3D-printed in round geometric shapes with integrated bass reflex ports using geometric stiffness instead of material stiffness.

I use a 100W compact GaN wall charger to power each speaker.

Best regards
Soren
 
Hi Emilime75

I'm using the ESP32-S3 as DSP. For $1,00 you get tripple 32bit cores - one 20MHz low power and two 240MHz high speed cores with floating point, DSP and vector processor acceleration. It also has built in wireless WiFi & BT 5.0 radio on-chip for direct digital audio streaming. I use TI class-D amplifiers with I²S digital audio interface and I²C configuration interface. This way there's no ADC and the DAC is in the class-D amp.

The amp depends on how much power you need. In my current project I'm using the TAS5828M that delivers 2x50W@4ohm, 100W@2ohm or 80W@3ohm. It's listed at $1,87 on Digikey. I use one amp per two speakers to avoid analog cross overs. The ESP32-S3 has two stereo I²S interfaces so you can run 4 speaker outputs in parallel. Bigger versions are available on the TI website if you need more power.
Would appreciate a writeup on this :)
 
Would appreciate a writeup on this :)
Hmmm - what kind of writeup?

I don't know your background but I can give you a few hints on what I use:
For cabinet acoustic design I use Room EQ Wizard and TS parameters from the speaker datasheets.
For mechanical cabinet design I use the free DesignSpark Mechanical software.
For schematic design and PCB layout I use the free DesignSpark PCB software.
I order 2 layer PCBs for $2 at JLCPCB: https://jlcpcb.com/ (my design fits on a 20x50mm 2 layer PCB layout)
They can also mount the components for $8 plus component cost.

If you use the ESP32-S3 Wroom module instead of the $1 chip it will cost you the double, but you'll get a CE and FCC approved module that will make the wireless approval procedure much easier (that's only important in case you want to sell your design). The module also includes EMC shield, crystal and 4MB FLASH. You just need to connect it to 3,3V to get it running. It's Arduino compatible (like an Arduino on steroids) but it's even faster if you program it in C. Another nice feature is that you just need to add an USB connector to have USB debugging. It's even got a built in JTAG debugger via the USB, so you don't have to buy a J-Link debugger to have a nice IDE with break-points and on-chip debugging. Both HW and SW is open source, so you can check out the documentation on espressif.com and Github.

If you use an external CE & UL approved wall adapter to power the speaker the approval process also becomes much easier. Again, if it's just for home use you don't need to worry about approval. You will need a small 3,3V SMPS for logic supply on the board. The ESP32-S3 uses less than 100mA with all 3 cores running full speed, and less than 200mA during Bluetooth communication (WiFi is closer to 300mA during transmission). There are plenty to choose from on the TI website. I'm using a LMR36506 in my design.

It's never been cheaper to get started on DIY digital amps with integrated DSP and wireless communication.
Good luck with your project. :)
 
Right, thanks. Not looking to sell anything, just looking for a small and fairly cheap DSP+amp solution with a good ADC to mount inside speakers. Was wondering if you used a proper PCB or more of a breadboard type contraption. I might just have to learn some PCB stuff. I'm decent with Arduino but all the I2C/I2S stuff throws me off :) Mind sharing your PCB design and some DSP example sketches? Did you heatsink the amp? The ones on esp-dsp git seem intended for purposes other than audio
 
I would say that the ESP32-S3-Wroom-1 N4 module is a fairly cheap DSP with CE & FCC approved WiFi & BT.
About $3 in single quantity: www.aliexpress.com/item/1005004412933815.html
The TAS5828M amp I'm using is also fairly cheap.
Listed at €1,75@1k units, but you might be able to get a few as free samples?: www.ti.com/product/TAS5828M
JLCPCB charges $5,33 if you let them mount it and buy less than 10: https://jlcpcb.com/partdetail/TexasInstruments-TAS5828MDADR/C5214953
It will cost you an additional $8 to let them mount the board (but I would also consider that cheap :))
I mount the PCB to a bottom alu plate in the speaker such that the top of the TAS5828M is placed against the alu plate squeezing a thin silpad.
I use a proper PCB because it's higher quality, more compact and cheaper.
The $2 price is for 100x100mm 2 layer - you can fit 10 pcs. of 50x20mm PCB's in that area.

I chose the BT->ESP32->I²S->Amp architecture to avoid an ADC and keep it lossless digital all the way from source to the output stage of the class-D amp.
You can download libraries for the I²C/I²S stuff from Github.
I can't share the detailed design because even though I'm designing it, it's my employers IP.
Take a look in the TAS5828M datasheet. :)
 
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