ELMYRA

From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive!

Moderators: Kent, luketeaford, Joe.

User avatar
Flounderguts
Super Deluxe Wiggler
Posts: 1594
Joined: Thu Dec 07, 2017 5:56 pm
Location: SLC
Contact:

Re: ELMYRA

Post by Flounderguts » Sun Oct 18, 2020 4:26 pm

Elmyra Schematic FG.png
Elmyra Schematic FG.pdf
(101.48 KiB) Downloaded 37 times
Please let me know if there are any errors :guinness:
----------------------

Flounderguts

User avatar
Flounderguts
Super Deluxe Wiggler
Posts: 1594
Joined: Thu Dec 07, 2017 5:56 pm
Location: SLC
Contact:

Re: ELMYRA

Post by Flounderguts » Thu Oct 29, 2020 6:32 pm

Question about the gits...

There seems to be a 1.2.1 version in place on the github.

I'm assuming the 1.3 version on the kits is for the 10k pots? I have rather a lot of 10k pots...is the 1.3 version available for download?

Thanks!
----------------------

Flounderguts

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Thu Oct 29, 2020 6:35 pm

The firmware is totally uncoupled from the hardware. You can use the newest tag with any of the hardware revisions. 10k pots are fine. I've used 22k before for some of them (the ones that act as voltage dividers to feed MCU input ports), but it doesn't really matter.

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Sat Nov 07, 2020 4:18 pm



Review of the build by Molten Music. :eurosmoke:

User avatar
oudplayer
Common Wiggler
Posts: 140
Joined: Sat Apr 16, 2016 8:12 am
Location: Brooklyn, NY
Contact:

Re: ELMYRA

Post by oudplayer » Sun Dec 06, 2020 7:07 pm

Just finished building this myself and have enjoyed playing with it; I'll post a video or two when I get a better handle on how to use it "musically" but so far it's been just what I was looking for in a drone box.

I agree with Molten that the build docs could be considerably improved; it would be easy to include pictures of what the populated PCB should look like (both sides) and to label parts better, and more info on just how we should create headers for the embedded chip would speed along the build process. With the mini resistors that are included, which had unclear resistance markings, I resorted to multimetering the resistors, which is fine in one regards, but for first-time builders who might not have a multimeter, they might get very frustrated with this step.

I also have an odd problem which is... well... inexplicable. So I start by touching the left two pads which gets the first voice going. If I touch the bottom-middle pad a 2nd voice is added, but the tuning knob that corresponds to that is the one on the right voice. Likewise, the right-bottom touchpad seems to correspond to the middle tuning knob. Is this the intended behaviour?
Makams and microtones in eurorack: https://makamqore.bandcamp.com/
Collaborative conceptual synthesis for the 2020s: https://manifestoon.org

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Mon Dec 07, 2020 2:14 am

Like I replied on the video: You don't have to measure resistors or resort to a multimeter. They're grouped into the bags in such a way that they're clearly identifiable as long as you don't empty all the bags into one big pile in the beginning... ;) There's a new updated build guide that has a big warning to that effect on the beginning.

As for the touchpad issue you're seeing: Could it be that the wires of your 4-pin cable are switched?

User avatar
Nelson Baboon
droolmaster0
Posts: 10411
Joined: Sat Nov 28, 2009 11:26 am

Re: ELMYRA

Post by Nelson Baboon » Mon Jan 04, 2021 9:21 pm

well, this appears to be the thread about the elmyra, though i confess that i have an assembled one on order.

I've been looking for the following info, but cannot find it. Can anyone let me know what was upgraded in 1.4 from 1.3? Thanks.

I must say that i found the sound in some of the demos of this to be very appealing. More so than the lyra-8. Seems crankier.....

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Tue Jan 05, 2021 5:59 am

Nelson Baboon wrote:
Mon Jan 04, 2021 9:21 pm
I've been looking for the following info, but cannot find it. Can anyone let me know what was upgraded in 1.4 from 1.3?
I usually reply to emails pretty quickly. ;) But I can also reply here of course: The v1.4 has an audio input. So it's now possible to use Elmyra as an effects unit, even while playing the internal voices. The external audio goes through the distortion and filter. It's described in the manual.

shiftr
Common Wiggler
Posts: 204
Joined: Thu Aug 08, 2013 4:33 pm
Location: Netherlands

Re: ELMYRA

Post by shiftr » Tue Jan 05, 2021 1:08 pm

Is it possible to add the audio input to the 1.3 version? Could you post the schematic of the 1.4 version?

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Wed Jan 06, 2021 6:15 am

Yes! It's a very simple mod. Elk Elektronik made a great video about it:



I'm working to put out a v1.4 schematic, but I'm a bit swamped with other stuff now, so it might take a while. The difference is literally just a jack and a 10k resistor though. Feel free to ask here or by email if you need any help.

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Wed Jan 06, 2021 6:18 am

Btw, the way I've done it before is even more simple: Just solder the 10k directly to the jack (shorten the legs first though, so it won't move later on) and the other end goes to the PCB via a short piece of wire.

User avatar
threedaymonk
Learning to Wiggle
Posts: 3
Joined: Mon Jun 01, 2020 8:30 am
Location: London
Contact:

Re: ELMYRA

Post by threedaymonk » Tue Mar 02, 2021 9:04 am

I traced out the version 1.4 circuit for my own interest before I found this thread, but as you're happy with people posting it, here it is:
elmyra.pdf
(60.89 KiB) Downloaded 45 times
It took me a while to figure out what bite actually does. It's bleeding off higher frequencies from the op-amp feedback loop, right?
neutral-labs wrote:
Wed May 13, 2020 6:50 am
As for sequencer sync, I've had many requests for it and am thinking about incorporating it in the future. Unfortunately there are no more free input pins on the microcontroller board.
I think you could gain three inputs by multiplexing the pots with a 4051. (It might then even be possible to add a fourth voice if there's a PWM output that can be juggled to run the fourth envelope LED.)

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Wed Mar 03, 2021 1:43 pm

Thanks, that looks correct. :)
threedaymonk wrote:
Tue Mar 02, 2021 9:04 am
It's bleeding off higher frequencies from the op-amp feedback loop
Exactly.
threedaymonk wrote:
Tue Mar 02, 2021 9:04 am
I think you could gain three inputs by multiplexing the pots with a 4051. (It might then even be possible to add a fourth voice if there's a PWM output that can be juggled to run the fourth envelope LED.)
My idea would be to use an input-sensing jack for the sync input. That way you could route the time knob voltage to the input on the ItsyBitsy while there's no external sync signal inserted. The code can be extended so it'll figure out whether it's a sync signal coming in (high slew rate) or the knob voltage (low slew rate). The sync signal must not exceed 3.3V at the ItsyBitsy IO port, so a diode clamp is needed on the input. And another 2.2k resistor on the positive voltage side of the time pot could make sure that the the voltage can never reach 3.3V when coming from the pot, which makes it even easier to tell apart sync from pot signal.

User avatar
threedaymonk
Learning to Wiggle
Posts: 3
Joined: Mon Jun 01, 2020 8:30 am
Location: London
Contact:

Re: ELMYRA

Post by threedaymonk » Thu Mar 04, 2021 8:07 am

neutral-labs wrote:
Wed Mar 03, 2021 1:43 pm
My idea would be to use an input-sensing jack for the sync input. That way you could route the time knob voltage to the input on the ItsyBitsy while there's no external sync signal inserted. The code can be extended so it'll figure out whether it's a sync signal coming in (high slew rate) or the knob voltage (low slew rate). The sync signal must not exceed 3.3V at the ItsyBitsy IO port, so a diode clamp is needed on the input. And another 2.2k resistor on the positive voltage side of the time pot could make sure that the the voltage can never reach 3.3V when coming from the pot, which makes it even easier to tell apart sync from pot signal.
That's a nice idea: it'll be easy to retrofit to existing hardware.

Kawouddd
Super Deluxe Wiggler
Posts: 1432
Joined: Tue Aug 25, 2020 12:09 am

Re: ELMYRA

Post by Kawouddd » Thu Apr 15, 2021 3:50 pm

P.1.

Instruction 1.

Missing 1 out of 4 LED holders 🤦‍♂️

I’ll just pause that build for a bit, then!

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Fri Apr 16, 2021 1:18 am

Sorry for that. As I just wrote in the email, it sounds like it might have gotten lost during shipping, since one of the bags was broken. Replacement is on the way, and it's no problem to finish the kit without the LED holder for now. Or just leave out one of the LEDs until the replacement is there. You Elmyra will work fine without it.

Kawouddd
Super Deluxe Wiggler
Posts: 1432
Joined: Tue Aug 25, 2020 12:09 am

Re: ELMYRA

Post by Kawouddd » Fri Apr 16, 2021 1:27 am

neutral-labs wrote:
Fri Apr 16, 2021 1:18 am
Sorry for that. As I just wrote in the email, it sounds like it might have gotten lost during shipping, since one of the bags was broken. Replacement is on the way, and it's no problem to finish the kit without the LED holder for now. Or just leave out one of the LEDs until the replacement is there. You Elmyra will work fine without it.
Appreciate that, Martin, and your swift response. Late night discouragement on instruction 1, but I’ll pick the build up later! Looking forward to getting this working. Cheers.

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Fri Apr 16, 2021 1:29 am

Great, just drop me a message or post here in case you have any questions.

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Thu Jun 17, 2021 2:02 pm

Really nice and thorough build video by C.K. Haun (unaffiliated):

Part 1:



Part 2:


Mallers
1-Post Wiggler
Posts: 1
Joined: Tue Nov 09, 2021 10:12 pm

Re: ELMYRA

Post by Mallers » Tue Nov 09, 2021 10:23 pm

My kit just arrived a couple of days back. Looking forwards to building and playing it

User avatar
neutral-labs
Learning to Wiggle
Posts: 40
Joined: Thu Mar 26, 2020 4:10 am
Location: Leipzig, Germany
Contact:

Re: ELMYRA

Post by neutral-labs » Wed Nov 10, 2021 5:54 am

Have fun with your build! Feel free to reach out if you need any help. :)

Post Reply

Return to “Music Tech DIY”