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• ESPHome support

  andriy.malyshenko • 06/12/2024 at 09:43 • 0 comments

  I spent some time lately playing with Home Assistant. What can I say, it is brilliant. So easy to use with ESPHome integration and so many nice things you can implement with ease.

  One of the things I didn't realize, is how easy it is to use ESP Audio docks and Loud ESPs with Home Assistant. It is a 2-minute job to onboard the device to the system, and then you can use it for playing audio or doing voice announcements.

  So far I've implemented

  - 'Announce hour' automation that is super helpful in the home office

  - For similar reasons 'Cuckoo clock' but also just for fun

  - Integrated Google calendar to announce the next meeting one minute in advance

  - Mopidy 'What is playing' monitor with remote volume and playback control + IR controls for the same 

  Anyway, the details are here, if you want to follow my steps

• Esparagus media center boards introduction

  andriy.malyshenko • 02/15/2024 at 14:56 • 0 comments

  Loud-ESP can be described as a universal tool that can be used for a bunch of occasions. You can feed audio either from cd-card or internet stream, you can control it via IR or button, you can visualize it on the screen or LED bar. You rather have a lot of choices about what to make of it.

  Even though I'm not too strong in software, I was constantly thinking what kind of project I'd like to do myself using all capabilities of Loud-ESP

  Streaming services have a lot to offer, and for devices such as Loud-ESP it is actually a replacement for UI (you have a phone to pick your tunes, no need for buttons). Also they would take care of music sources, as long as the internet is available. Screen is nice to have, but again you have everything you need on your Spotify app.

  At this point I started to get rid of the peripheral that I don't really need, giving up sd-card, battery management (I personally don't move speakers around at home) and even screen. I replaced it with an aluminum case that gives that finished look and feeling that it is no longer a development board but a product. At this stage Loud Esparagus was born, which follows the Loud-ESP in many hardware aspects, but much more focused as a consumer product.

  Another major change coming was obviously the DAC, which had to be upgraded to something more capable. MAX98357 used in the Loud-ESP is a great little IC, but to drive a large speaker you have to bring more power, and here TI has many options to offer, in fact that are basically own the market. It was not a hard task to find the one DAC that has the right input, the right power and the right level of support.

  Last piece of the puzzle was to address those that already have amps at their homes (As I do). Perhaps they already use it with different sources and don't foresee a need to change it. Esparagus Hifi Medialink is the last board in the series that brings streaming capabilities to dumb old amps. It has line level output via Hi-Fi (and I mean it) DAC and can be connected to your beloved audio gear to prolong its life in the 21 century.

  Summarizing, you have a HiFi version that you embed into your existing setup, adding modern sources to aging hardware. Then you have Loud Esparagus, that is not way too powerful, but combined with small speakers can enlive a small room or work place. And there is Louder Esparagus which would be a full scale media center you usually find in the living room (or dorm) with relatively large speakers.

  I passed the formalities necessary to actually start a Crowd Supply campaign to support production of the Esparagus series boards.

  If you're a hobbyist maker it is actually very hard to produce these small projects in small volumes, because of fundamental costs of initial development. When you know in advance what kind of volumes you should expect to produce, it is much easier to build up an adequate price for the unit. 

  Public campaigns also help to understand if a product is finally ready for a launch, as adding improvements and new features is a never-ending effort. At some point you have to say "Although it's not perfect, it's sufficiently near".

  I invite everyone interested to subscribe to campaign updates, as in coming weeks I will need to work hard to finalize the design and prepare for the production run, which will strongly depend on the community interest.

• Squeezelite-ESP32 support

  andriy.malyshenko • 11/16/2023 at 21:28 • 0 comments

  Recently few people contacted me regarding support of squeezelite-esp32. I did some test long ago, and it felt like LMS is a nice piece of software and had few cool features for it's time, but frankly feels out of loop in 2023.

  Well, I was wrong. Today it supports both Apple AirPlay and Spotify Connect, not mentioning Bluetooth connectivity. Actually for ESP32 power house that is much more than you'd expect. Especially the Team working on Squeezelite-ESP32 is actually spent some good time working on stability and [using it for a few days] so far I had no crashed or weird behavior.

  Long story short, guys confirmed me that it is okay to pre-flash Squeezelite-ESP32 before selling them, as well as simply advertise it's support.

  I put step-by-step instruction to help others to setup Squeezelite-ESP32 on the project's github, and welcome everyone to give it a try.

• Loud ESP is on sale on Tindie

  andriy.malyshenko • 08/23/2023 at 21:04 • 0 comments

  As all Crowd Supply orders are shipped and delivered to respective backers (thanks every single one of you!), I'm listing Loud ESP on Tindie as well. Price is the same as CS or Mouser, but if you're in Europe, delivery probably will be cheaper from Tindie. That's because I'm myself live in Europe.

  Looking forward to hear from any of the backers on their projects and use cases.

• Crowd Supply campaign is live

  andriy.malyshenko • 03/10/2023 at 19:53 • 0 comments

  Having all preparations ad testing done, our campaign is finally live! Financial target is really modest, but enough to push the price down to $30 for mini version, including all taxes, fees and charges.

  Last week before campaign I spent porting nice [Visualizer](https://github.com/donnersm/TwinVisualizer) project created for Teensy boards, and having some cool visualisations on the screens same size and resolution as mine.
  

  Code is not processing audio just yet, rather visualisation-only proof-of-concept. But final result is just as appealing, as the prototype. So I leave it to better coders to actually attach it to fft-processed audio stream.

  
  

• Now available on Tindie

  andriy.malyshenko • 04/28/2022 at 22:15 • 0 comments

  To support my Crowd Supply launch I've decided to promote ESP8266 version of the board via Tindie store. This board is a baby version of ESP32 design, lacking some features and having much smaller power house. I consider it 'just enough' for smaller projects, like talking gadgets or sound boxes, left alone speechless visual projects that can start talking with this board.

  
  

  All funds received will go for ESP32 version development, which I hope will see the daylight, as long as the project pre-launch will receive enough subscriptions. Having that said I'd like to ask again everyone to subscribe to Crowd Supply campaign, I'm really keen to release it to backers and see the projects it can host.
  

• Crowd Supply campaign is pre-launched

  andriy.malyshenko • 04/04/2022 at 17:50 • 0 comments

  Just wanted to mention that I'm starting preparations for Crowd Supply campaign. Actually some work already performed and pre-launch page is live now. Currently I'm collecting subscribers that would be the basis for price and volume calculations, and if there is an interest for the board in the first place.
  

  I'd appreciate if everyone interested in this board to see daylight would subscribe, mainly because only high enough volumes would allow to keep the price reasonably low.
  

  
  

• New mini board and smart speaker projects

  andriy.malyshenko • 03/30/2022 at 14:08 • 0 comments

  I've decided to run funding campaign for this project with Crowd Supply. I did it before with another project of mine and it went well. This means among other things a huge to do list for me, including finalizing design (and feature list accordingly) and working on thorough testing and validation.
  

  Closing feature list is the most complicated for me, since it is always so tempting to add few more bells and whistles here and there. Good method in that case is implement something myself and check what is missing and what is not used along the way. Following that path I've came to conclusion that I need mini board - this designed to be placed inside all kind of smart speakers and therefore has no screen and generally take considerably less space.

  I introduce to you ESP Audio Development Board Mini
  
  

  
  And here they are together with full-size boards, both ESP8266 and ESP32 models
  
  Compared to their full-size counter parts they've lost SD card and IR connectors, but in terms of audio capabilities, they're equivalent.
  
  One question I got asked by CS team is what for I'd like to have ESP8266 model, and point is - it costs almost the same, but far less capable. I don't know it myself, it isn't rational, but I still prefer to do simpler projects with smaller MCU, perhaps I get some kind of satisfaction when MCU resources are used as much as possible.
  
  As I said above, best way to validate design is to implement something yourself, and for that purpose I've built 2 small speakers project
  
  The first one is a small, but extremely loud for it's size, alarm speaker. It started in life as a DIY bluetooth speaker, but given it's audio capabilities I've decided repurpose it.
  
  

  So the first step is to disassemble original speaker

  
  
  Then I'm placing inside ESP8266 Audio Dev mini board, connect both speakers to amp outputs and power switch to header
  
  Power comes from 18650 battery placed on the back side and secured using couple of screws
  Then it is secured inside using standoffs the way that USB port is accessible from the side to allow charging and flashing (although I'm using OTA updates for simple changes)
  
  I've secured a window on the top to allow indication using built-in addressable LED, and here is the end result
  

  And the second project would be more sophisticated speaker based on ESP32 version of the board and great cspot repo which implements Spotify speaker on ESP32 chip.

  To house this project I've bought Logitech iPod speaker (that what we've called smart before). It has no use in today's standards and anyway it is sold as broken and I couldn't care less if it was possible to fix it.

  
  
  

  First I need to disassemble it and I did a monkey job of it and broke a couple of parts on the way, but in the end it is showing it's internals

  
  It has Li-Ion battery inside that I will use and 2 speakers (2 passives also), which is also match.
  

  Here is the original PCB, it goes to spare parts box
  

  Connections that I've made are following
  - Both speakers are connected using stock wires
  - On/Off switch will be placed on the buttons panel, as well as addressable status LED
  - Stock battery connection
  - Charging port soldered directly to USB 5V line - i can charge it using built in power port (and play audio at the same time)
  
  Than PCB screwed in place using one of the stands left from original PCB
  Last touch - place power switch and status led on the buttons panel, it was broken before, so my connector trying to replace missing piece
  End result doesn't look much different from the original speaker, but now has Spotify capability
  
  

  
  

• Revisiting MAX98357A DAC

  andriy.malyshenko • 02/18/2022 at 14:13 • 6 comments

  When I've tested MAX98357A module before in this project, I came to conclusion that it is only capable to produce moderate quality audio for non-demading projects. Funny enough I couldn't be more wrong about it.
  

  While performing audio tests with the development board shared in the previous post I got the same scores, quite disappointing audio quality with hearable distortions. Datashees was much more optimistic on the chip's performance, so I sit to play around with some components to see if I can make it play better. Since there are not so many components to play around with, I started poking around output filters.

  
  

  Originally I put output LC-filters similar to Adafruit's module as on the picture above. Not very happy with the result I revisited MAX98357 datasheet and found that it does not require any output filters apart from the speaker itself service as LR filter

  So out of curiosity I've removed the filters altogether and funny enough DAC started to produce clear audio! Below is waveform with no filters (taken from toy-oscilloscope, sorry again)

  1KHz 
  

  2KHz
  10 KHz
  
  20 Khz
  
  It doesn't look very promising just yet, but at least it works up to 20KHz with no issues. Much better than before.
  
  Next I've connected simple RC filter with 2Ohm (1Ohm per output) and 4.7uF cap in parallel to setup first order Low-pass filter set to filter out frequencies above 16KHz, which is reasonable margin for relatively cheap speakers I have. Here is the waveform behind filter
  
  1KHz
  
  2KHz
  10 KHz
  
  20 KHz
  Now it looks much better and I claim this result as acceptable.
  
  The only issue I have now is that having 2Ohms in parallel with 6 Ohms speaker push down efficiency quite a lot (although it is not dramatic when you hear the difference) and resistors warming up quite badly. If I decrease resistor value to 1 Ohm (.5 Ohm each output) output stage is losing stability.
  
  So in the end I'm going for no filter at all, just as datasheet says. I can't hear the difference really, and efficiency means more to me in the context of battery life.
  

• New custom PCB - MAX98357 powered stereo amp

  andriy.malyshenko • 02/09/2022 at 21:31 • 0 comments

  Based in the investigation done in this project I've decided to build series of development boards with audio capable DAC, starting from the ones with built-in amp. Since I already have in mind a kind of project I'd like to implement (no spoilers) i also planned some advanced peripheral on the board to support those projects.
  

  To be fair I've done both ESP8266 and ESP32, since in my opinion they are both great chips and being similar on the paper, they are in a quite different league if it comes to power reserves, therefore they are not really competing. For smaller projects I prefer simplicity of ESP8266, for larger projects - spacier ESP32.
  

  I'm using them both quite regularly, so why not to have 2 development boards instead of one.
  

  With that said, here they are.
  

  ESP8266 closer look

  ESP32 closer look

  So commonly they have
  

  - Stereo DAC with built in amp (2x MAX98357)
  

  - Power circuit with backup Li-Ion battery (using built-in battery holder or external using battery socket)

  - Battery charging IC and battery overcurrent protection IC

  - Battery voltage measurement with built-in ADC
  

  - Boost converter to keep the music going when battery voltage is too low

  - TFT screen (with touch support on the ESP32)

  - USB-serial bridge for normal flashing and serial debugging, with auto-flashing circuit

  - IR reciever to support IR remotes

  - Micro SD-CARD socket

  Given the extra pins on the ESP32 is exclusively has

  - RGB led on the board and connector for the external RGB LED strip

  - PSRAM

  - Joystick OR rotary encoder
  

  - Few HW touch pads
  

  - JTAG header for real debugging

  Currently I'm testing all the peripherals and doing some small improvements. Also I've adopted cspot repo to play Spotify as a smart speaker, and looking into adding visual feedback to above project. I want to put it into the case, for that purpose I've bough broken smart speaker and planning to replace internals with my dev board. More details in the next post (hopefully).
  

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