This is a placeholder topic for “6+1 Microphone Array” comments.
In here I2s output is in which form? Stereo or time-division multiplexing. PLz, reply immediately.
Hi Asjath,
I haven’t used I2S myself before, but I’ve had a bit of a dive into it and I’m still not clear on your question.
Page 10 of the datasheet for the microphones used in this array may answer it for you:
I’d also recommend checking out this I2S specification from Cypress:
https://www.cypress.com/file/137371/download
The section on Data interleaving on page 7 may be relevant?
Thank you very much.
In the I2s protocol, we can get only two microphone signals left and right channel. Therefore only two microphones can connect to the Raspberry Pi 4 at a time. Is there any way to connect more than one I2s inputs to the Raspberry Pi 4?
Ah I’m with you. This module has 3 stereo channels (MIC_DAT0, MIC_DAT1, MIC_DAT2) which are for the 6 peripheral mics, and a mono Right channel for the centre mic (MIC_DAT3).
This Mic array is really intended to be used with a K210, as all the example scripts are in MaixPy (Micro Python for the K210).
https://maixpy.sipeed.com/maixpy/en/develop_kit_board/module_microphone.html
Here’s the links to the schematic and PCB layout:
https://dl.sipeed.com/shareURL/MAIX/HDK/Sipeed-R6+1_MicArray
But there are a few really good threads on running multiple I2S channels on a Raspberry Pi on the Official Pi forums:
https://www.raspberrypi.org/forums/viewtopic.php?t=55799
https://www.raspberrypi.org/forums/viewtopic.php?t=106372
https://www.raspberrypi.org/forums/viewtopic.php?t=231065
If you have the budget, the easiest way to use this with a Pi 4 might be to use a USB audio interface like this:
https://www.minidsp.com/products/usb-audio-interface/usbstreamer
Thank you very much Oliver
Hi Oliver and the team at Core, I think this product could sell better with a bit more effort to bring together the data/techniques on how to use it. I’m interested in a project based around it, but it just seems so loosely defined, that my project could go nowhere because I’d struggle through finding the right connector, understanding I2S etc etc. The first link is to a non-safe webpage, the introduction is oddly written (translated or by a non-native speaker), it just doesn’t inpsire confidence. I’ve never heard of K210 and was just hoping to interface to a teensy 4.0 Just thought I’d provide this feedback and hope you can bring this product out of its shell, explain it better and hopefully get everyone excited about it.
Hi Daniel,
Welcome to the forums!!
I can definitely agree with you on some of the product pages, once someone stubles upon them the Core guys are super quick to add as much as they can to them though.
Imo I think thats where Core sets themselves apart from other electronics stores, on the forum there is a ton of help about all of the different parts they sell. Being said that is also the nature of the hobby, sometimes you’ll hit a roadblock with a particular board or software implementation.
From the looks it it there are some jumper wires that come with the product, but if you were making a PCB to go with it an IDC cable would be your best bet to plug in (not sure if this one is the right pitch).
Most of the time libraries or API’s are pre-written it interpret protocols such as I2C, SPI, UART, (depends on the devboard, it looks to be implemented on the Teensy but only with one channel).
The link takes you to DFrobots website, its the brand that Core has this one under, they have some neato boards at a good price, but not quite the documentation like PiicoDev, Adafruit or Sparkfun.
I found this on the K210, looks to be a super juiced up MCU: https://www.seeedstudio.com/blog/2019/09/12/get-started-with-k210-hardware-and-programming-environment/
I’d definitely be keen to see this board fleshed out as well, I’d imagine @Donald23173 from this thread would love to see them as well!
PS: For a higher price you could also try Seeed’s multichannel mic, while the price is higher it offers driver free installation (not sure if an RPi will support it out of the box)
EDIT: just came across this devboard featuring the K210: https://core-electronics.com.au/maix-bit-ai-development-board-risc-v-k210-iot.html
As I understand it, the cheaper multi-mic array boards (eg reSpeaker 2-mic HAT, Adafruit Voice Bonnet, Raspberry Pi IQaudio codec zero, and this board) all have the hardware capability “by which to solve some problems such as noise and echo suppression, reverb cancellation, single or multiple sound sources localization, and so on” … but after purchasing you find that these functions are not built into the firmware. You have to add them in your own software.
I recall considering this device, but looking for the firmware/driver/software, but was put off by the support documentation since I am not fluent in Chinese.
The ReSpeaker USB Mic Array which you linked to claims to have these features already in the firmware out of the box - which is great - but at $130 each, not something I can afford for multiple rooms in the house. Especially considering that home voice assistants are competing with Google and Amazon hardware from $59 (or $19 during black friday sale).
In practice, a cheap USB audio device plus speaker and single mic will work just as well for those of us trying to create a cost-effective home voice assistant.
Hi Donald,
Welcome to the forum!!
Definitely, we’re more than happy to help so if you have any suggestions on how we could improve a product page we’re more than happy to jump in and try our hardest!
As for your project, what were you looking to do? I can see @Liam120347 linked a microphone array from Seeed but without context, it might not be the best part.
Thanks for chiming in Donald!, I remember reading the topic about your satellite Pi’s sounds awesome!
Let us know what you’re thinking Daniel!
Liam.
Thanks everyone.
I think MEMs microphone arrays have fascinating potential, but still haven’t found the right gear yet. The 6+1 Microphone Array looks right from a hardware level, but complete lack of detail makes it unbuyable. On the other hand, the ReSpeaker USB Mic Array has the right firmware and better detail, but the plastic case and other features are unnecessary, and with only 4 microphones will only be capable of basic applications. The interesting thing is there’s a broken link on the Core Electronics ReSpeaker page talking about a dev board equivalent (1st link in description text)- what is the correct URL please?
If I can’t get the dev board, I may go with the fully constructed ReSpeaker option just to get me started on something. So far, I guess it’s case of goldilocks needing something not too hot, not too cold… I’d like something like: 6-12 MEMs microphones (ideally with a daisy chain feature to other boards), just the circuit board, and good software support.
Thanks all
And you can get our latest projects and tips straight away by following us on:
