Author Topic: Questions about adding line in to DIY Glo  (Read 370 times)

pabloantxon

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Questions about adding line in to DIY Glo
« on: May 10, 2019, 11:37:43 AM »
Hello!
I received my DIY Glo two days ago and I'm loving it, it makes just typing at work a relaxing experience. I don't know about further experiments, but the way it already works as it came it is perfect :)

I'm looking at adding a line input to see what comes out of it when I connect my synths and stuff.
I've seen in the Hardware Extensions section ( http://phonicbloom.com/diy/make_your_own_enclosure/ ) that you can solder a line input to MIC2 L and R pads and I have a question.
I guess the tip and the ring of the mini jack go to the L and R pads, but what about the sleeve? Should it go to the AGND pad?

And another question:
If I add the line input, will I be able to choose the board microphones or the line input as the audio input, or will both work at the same time unless I change it in the software?

mario

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Re: Questions about adding line in to DIY Glo
« Reply #1 on: May 13, 2019, 12:04:05 PM »
Happy to hear it arrived in a good shape and you are enjoying it! :) I've had it on for hours while working on the laptop too, mostly on decaying reverb, typing sounds very cool with it.

Yes that's correct, the line input should be wired to MIC2 and AGND. But there should be 100nF-470nF caps in series with L/R lines (with larger capacity, lower frequencies get transferred - I usually add 220nF only, sounds great with them). The datasheet with more details about the codec is here if you need to check something.

In the current firmware there is no automatic detection or option for this yet, but there will be a parameter in config file to switch to the third and fourth option - line-in and both mics & line-in mixed, by pressing (+) and (-) together, the same way as you can now switch mics on and off. And perhaps add an option to make this a persistent setting that is remembered during power off.

By the way there is a new article about expansion board, planned to have it in the shop but there is a small error in it that requires rework, the 100k resistor needs to be mounted sideways. Until I get to fix it and order more, there are a few available - feel free to email me if you are interested in one. It expands Line-in and out, and also MIDI both ways through the 3.5mm Jack. Here it is shown in action, it's the previous version that did not yet have LEDs and used different keypad driver that did not work well.
« Last Edit: May 13, 2019, 12:34:20 PM by mario »

pabloantxon

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Re: Questions about adding line in to DIY Glo
« Reply #2 on: May 17, 2019, 12:33:16 PM »
Hi!

Great, I'll use 220nF caps then :)

About the firmware, is it open source? Have you uploaded it somewhere? I would like to take a look at it. If it is not don't worry, I understand you are very busy right now sending all the glos and working on the gecho v2.

I am interested in that board, I wrote you an email to gechologic at gmail dot com :)

Thanks for your reply!

Pablo

mario

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Re: Questions about adding line in to DIY Glo
« Reply #3 on: May 18, 2019, 12:23:55 PM »
Hi Pablo, yes the firmware will be open - it is based on other open source projects, so it could not even be any other way. I'll put it here next to the Gecho firmware, just need to clean up the code a bit. Thanks for the email, will reply soon! :)