Major EXOGAL Comet/Ion problems

@damianhl incredible stuff! I too agree that the Exogal Comet Plus has perhaps the most natural timbre of any DAC I’ve owned. The mids are simply beautifully depicted.

I spent some time not long ago probing the Bluetooth chip output in my Comet, trying to understand the pulses it sends to create a directly wired replacement. My one gripe with the DAC is its UI - the remote and the android app I run on an old phone have proven to be unreliable and quite slow. 
 

I’ve considered replacing or piggybacking off of the Bluetooth receiver with an Arduino or RasPi, either to have directly wired physical controls or to create a web interface for the DAC. Any documentation or help would be greatly appreciated. Thank you for helping keep this DAC alive!

- Mike

Hi @damianhl

Thank you! I agree, Jeff has been a wonderful help. I should’ve checked here earlier because I too wrote an app that interfaces over serial with Comet! I wrote mine in Python since it’s what I’m familiar with and easy to port to any modern OS.

It’s a simple button based GUI app that currently allows you to select which COM port, power on/off, choose input/output, mute/half mute /unmute, increase/decrease volume or enter a specific volume value.

I’m currently working on adding a rotary encoder and an IR receiver to a RasPi Pico to handle desktop volume adjustment and living room IR remote use. In the future, I would like to run it all off a full RasPi to add streaming capabilities. There are a lot of hidden functions on comet that I’m excited to see implemented, but right now this is where I am.

I am so thankful to Jeff, Bob, and to you for helping keep this DAC alive and well. Maybe we should start a new thread, but I’m happy I at least landed here. Thanks!

Mike

Did it
 

Working on screen and buttons :)
 

@markhh2 hi!

The easiest option is via PC. All you’d need is a USB to serial (5v TTL/UART 3.5mm. $10-30) and the app I’ve been working on. There are a few kinks I need to work out but I should be able to reach out when alls said and done. It looks like this for now:

Update: 3/19/2023

IR remote code is COMPLETE! There are some oddities:

1. The 'Mute' functionality isn't controllable over serial, only Bluetooth. There's a note about it 😔 While you can't mute from the IR remote (could set Vol = 0 I guess), you can unmute! 😀

2. The NEC protocol (common for 'universal' IR remotes) specifies 'repeat' functions in a silly manner - if a button is held, regardless of the button, the 'repeat' command sent is identical 🤨 I have not ironed out logic to allow holding Vol +/- yet for this reason  

Just about any IR remote can be coded in. A friend found some awesome OEM aluminum remotes, went ahead and ordered a few to test Happy with the progress so far! I don't have a lot of time to devote to it, but I am excited to have it done haha.

Update: 3/23/23

Finished the desktop app! 😀 It's more or less feature complete depending on the DAC firmware version (some don't have 'Mute' control available: to unmute, simply press one of the volume buttons).

The app is written in python and made stand-alone with 'pyinstaller'. No need to install anything, simply unzip the folder and open the 'CometCampground.exe' (I thought the name was fun). It should automatically choose the right COM port: If not, it can be clicked to show a list. To use it, you'll need this cable (non-affiliate link): https://www.amazon.com/dp/B07J3XS7DQ?psc=1&ref=ppx_yo2ov_dt_b_product_details

I take no responsibility for anything at all: not for damages, the apocalypse, your DAC and life spontaneously combusting to smithereens, etc. You use it at your own risk :) With that out of the way, the goods - Dropbox link to the app: https://www.dropbox.com/s/52uewv1uzqe24gu/CometCampground.zip?dl=0

Exogal gear still holds better resale and musical value than your gear takes rtorchia 😂go back to simping Amir and listening with SINAD instead of your ears.

Myself and others I know like what the Exogal team made because of the way it sounds - they made something special. Why else choose to own a piece of audio equipment? 😉

I am doing what I can to help others continue to enjoy that gear in new and (hopefully) helpful ways. It's a learning experience for me for sure 🙂 I keep updating progress here and in other threads in the hope that it reaches everyone looking for such a solution. I've mentioned this before: IR remote and desktop control are features I've been searching for long enough to finally try to do it myself. Huge thanks again to Jeff and Bob, as well as Jan and the rest of the Exogal team, for helping me get these projects started and for making this special piece of kit ☺

Update: 3/24/2023

Since native mute functionality isn't accessible over serial for every firmware revision, I wrote custom logic/code to add mute capability to the IR remote! I'll add it to the desktop app as well 😊

Update: 3/28/2023

Updated the app to fix a stupid mistake on my part - I didn't include the app icon in the distributable! Also made it one simple executable file.

Comet Campground (desktop remote) v1.1:
https://www.dropbox.com/s/8o1ue5a9pio8bae/CometCampground1.1.exe?dl=0

Important update - that version of the app is borked: I didn't include the app icon in the distributable! After I did so, it triggered Windows Defender. Oof. So instead I kept it one simple executable file and signed it with a Windows Security certificate so it shouldn't trigger your antivirus. First run takes a second but after that it's quick.

Long time no post. Apologies, life finds a way. I'm hoping to finalize the hardware design in the coming months. If that does not in fact happen and you, the reader, feel so inclined - please feel free to PM me 😊

@ciszyn11 This application doesn't work in Android, however the official APK is out there. Works on older Android handsets, before Android 9. The one I wrote is primarily for Windows. @yoby It's not possible to program a universal remote without some interface to the DAC, since it only has hardware for a specific set of calls over BT.

What @rtorchia is referring to is probably the Pulsar. I have one, it's a BT repeater that works with any IR remote and interfaces with Comet. It does work very well, but is tricky to find. The physical remote it came with looks the same as the proprietary BT remote, but at least with the Pulsar add-on you can use most any NEC IR remote. My hardware solution seeks to do something similar with more features. I need to start working on it again. Life happens lol but hopefully some have been helped so far