Soma - LYRA-8 DIY Kit

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steviet
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Re: Soma - LYRA-8 DIY Kit

Post by steviet » Wed Nov 25, 2020 12:27 pm

grm wrote:
Tue Nov 24, 2020 7:01 pm
grm wrote:
Thu Nov 05, 2020 3:13 pm
jkammerl wrote:
Sat Oct 24, 2020 6:43 pm
Thanks for the quick response! I found the problem.. The LFO signal first goes to the IO board (since it can be replaced with an external CV modulation source). There I found a problem with the header on the control board side. Once I fixed it, everything worked!
great that you found the source of the problem, maybe that is the same issue as i have.
could you please specify where the problem on your build was?
i have checked continuity and that is ok for all pins.
and
DLY IN is connected to the input pin (tip) of the CV DELAY socket.
DLY.SOURCE is connected to the switch pin of the CV DELAY socket.

and here's hopefully useful pictures of the full mainboard and the I/O board.
(one thing i can spot is a slightly melted 470nF cap, that i touched with my soldering iron, but usually they survive when it happened before. or could that be it?)
anyone? :roll:
Can you try using an external modulation source to see whether or not that works? I'll take a closer look at your pictures tonight if I get a chance to see if we can get it working proper for you :sb:


EDIT:

Took a look at the images, everything looks fine to my eyes. The wiring between the jacks and the I/O board seem fine, but that is something you could look into. It might be that the CV Modulation input "thinks" something is plugged in, and therefore isn't routing any modulation.
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Re: Soma - LYRA-8 DIY Kit

Post by RadHazard » Sun Dec 06, 2020 8:03 pm

Has anyone received a kit recently? I've been on the list since September 28 at which point they said it should be in stock soon. Also been on the list for a DVINA since early October but haven't heard anything since the initial confirmation. Just want to make sure emails haven't been blocked or something.

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Re: Soma - LYRA-8 DIY Kit

Post by hiegdk » Mon Dec 07, 2020 12:55 am

Here's a couple of photos of my (mostly) finished build.
IMG_0126.jpeg
IMG_0129.jpeg
IMG_0128.jpeg
IMG_0127.jpeg

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Fine tuning

Post by eltnet » Mon Dec 07, 2020 11:32 am

Hello, I didn't find it discussed anywhere.
Is it possible to add fine tuning for each voice with a concentric potentiometer?
How to ?
I already found the solution with precision 10 turns pot.
Cheers.

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Re: Fine tuning

Post by Flounderguts » Mon Dec 07, 2020 11:47 pm

eltnet wrote:
Mon Dec 07, 2020 11:32 am
Hello, I didn't find it discussed anywhere.
Is it possible to add fine tuning for each voice with a concentric potentiometer?
How to ?
I already found the solution with precision 10 turns pot.
Cheers.
You're trying to make it work with a "coarse" and "fine" type setup?

The "tune" pots for each voice are set up as adjustable resistors, rather than voltage dividers. So you should be able to rig it up so that the center pad goes into the coarse center pin, then from the coarse right pin to the fine center pin, and out the fine right pin back to the board.

You will want a pot with a much greater scale on the coarse part of the pot, and a smaller scale on the fine. The silkscreen calls for a 100k pot, so maybe 100 outer and 1k or 5 k inner?

It's a bit of a kludge, but I don't see why it wouldn't work.
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grm
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Re: Soma - LYRA-8 DIY Kit

Post by grm » Wed Dec 09, 2020 5:19 pm

steviet wrote:
Wed Nov 25, 2020 12:27 pm
grm wrote:
Tue Nov 24, 2020 7:01 pm
grm wrote:
Thu Nov 05, 2020 3:13 pm
jkammerl wrote:
Sat Oct 24, 2020 6:43 pm
Thanks for the quick response! I found the problem.. The LFO signal first goes to the IO board (since it can be replaced with an external CV modulation source). There I found a problem with the header on the control board side. Once I fixed it, everything worked!
great that you found the source of the problem, maybe that is the same issue as i have.
could you please specify where the problem on your build was?
i have checked continuity and that is ok for all pins.
and
DLY IN is connected to the input pin (tip) of the CV DELAY socket.
DLY.SOURCE is connected to the switch pin of the CV DELAY socket.

and here's hopefully useful pictures of the full mainboard and the I/O board.
(one thing i can spot is a slightly melted 470nF cap, that i touched with my soldering iron, but usually they survive when it happened before. or could that be it?)
anyone? :roll:
Can you try using an external modulation source to see whether or not that works? I'll take a closer look at your pictures tonight if I get a chance to see if we can get it working proper for you :sb:


EDIT:

Took a look at the images, everything looks fine to my eyes. The wiring between the jacks and the I/O board seem fine, but that is something you could look into. It might be that the CV Modulation input "thinks" something is plugged in, and therefore isn't routing any modulation.
Oh, thank you for your help. It took me a while to get back to it.
i did try with a CV signal from a microfreak (1V/OCT) to the CV VOICES input jack, with 'some kind of success':
there are some settings consisting of the relation between MOD, individual VOICE pitch and the TUNE of the 4 oscillator block.
but it is a very small usable range.

i have then looked into your thought of an issue with the CV jack's 'thinking again, and checked from the 'backpanel jacks' PCB again. and there i found the issue, indeed. :mrgreen: the CV VOICES jack need a switching ground jack, meaning when nothing is plugged in a bridge between ground and pin 6 of the 4016 IC next to it shall be made. now the modulation with LFO as well as the 'FM' works.

THANK YOU! :tu:

PS: since i do not have a 3.5mm socket with a switching ground connection, (which would be a suitable part?) i will for now install a manual switch.

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Re: Soma - LYRA-8 DIY Kit

Post by steviet » Fri Dec 11, 2020 1:06 pm

grm wrote:
Wed Dec 09, 2020 5:19 pm
Oh, thank you for your help. It took me a while to get back to it.
i did try with a CV signal from a microfreak (1V/OCT) to the CV VOICES input jack, with 'some kind of success':
there are some settings consisting of the relation between MOD, individual VOICE pitch and the TUNE of the 4 oscillator block.
but it is a very small usable range.

i have then looked into your thought of an issue with the CV jack's 'thinking again, and checked from the 'backpanel jacks' PCB again. and there i found the issue, indeed. :mrgreen: the CV VOICES jack need a switching ground jack, meaning when nothing is plugged in a bridge between ground and pin 6 of the 4016 IC next to it shall be made. now the modulation with LFO as well as the 'FM' works.

THANK YOU! :tu:

PS: since i do not have a 3.5mm socket with a switching ground connection, (which would be a suitable part?) i will for now install a manual switch.
:sb: Super pumped for you!!

As far as the jack goes... I can't find any 3.5mm off hand. I used the 1/4inch jack specified in the BOM. I'll try to take a look around for you this weekend if I have some time.

In the meantime, enjoy the whackiness of the Lyra-8!!!
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Re: Soma - LYRA-8 DIY Kit

Post by Voltage_Controller » Fri Dec 11, 2020 5:50 pm

Are these diy kits still avail?
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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Fri Dec 11, 2020 7:13 pm

Voltage_Controller wrote:
Fri Dec 11, 2020 5:50 pm
Are these diy kits still avail?
Yes. Email Soma Laboratory to get on the waiting list for the next batch.

For those of you who decided to use carbon composition resistors for your build (like steviet), you may find it hard to source 1/4 W 200K resistors. I found some at Elliot Electronic Supply, but they are a bit spendy at 40 cents each plus a shipping fee over twelve bucks. If you can find some other stuff on their site, it may soften the blow! I found they had 20M pots, so I'm going to see if they fit the release slow!

I'm doing a lot of research and experimentation to eliminate the snappy LFO bleed that many people experience in their builds. I'm about to try a bunch of LEDs that draw very low current (thanks to Blippenschpeil)
The snap from the LED goes throughout the entire output circuit, and it's very visible on the scope. I have been able to change the shape of the snap (to a lower frequency thump, but at a higher amplitude) by using very high output LEDs (and I love the way the pink one looks!) but I'd like to find a solution once and for all, since this issue is not present on the factory boxes.

I've also had a bit of time with the expanded build, and I'm testing some different components and values. I'll post on the other thread about that when I have some concrete results.

Also, I will have some more regular panels at flundrton.com pretty soon. Shipping from overseas is ridiculous right now...I should have had them weeks ago. There will be two types...the one I originally made (tweaked) and another one to fit the Hammond 12123 enclosure.

Anyone who is hoping for a gate in expander, I am waiting for parts for breadboard V4...the circuits work, but the power draw is stupid...and the one with the low power draw fried when I hit it with a high energy gate, so I'm trying a new approach using optoisolators.
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Re: Soma - LYRA-8 DIY Kit

Post by grm » Sat Dec 12, 2020 7:46 am

steviet wrote:
Fri Dec 11, 2020 1:06 pm

:sb: Super pumped for you!!

As far as the jack goes... I can't find any 3.5mm off hand. I used the 1/4inch jack specified in the BOM. I'll try to take a look around for you this weekend if I have some time.

In the meantime, enjoy the whackiness of the Lyra-8!!!
Hey, thanks again.
no need to look them up for me. i am fine with just adding a toggle next to the socket.
i was just wondering, about the parts, i don't think i have seen a panel mounted one with ground switch, but what do i know.

i have enjoyed the extended wackiness a lot already. i was already pleased with the sound without the MODULATION working, tbh.

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Re: Soma - LYRA-8 DIY Kit

Post by wrentema » Sat Dec 12, 2020 3:27 pm

Hello!
My first post here. It was already super helpful reading this thread. Got most of my questions answered. And found a front panel (thanks Bamboombaps). But I have three things:

1 - CCCP CAPS - I'm still curious about the mysterious CCCP .1uf capacitor. Does it affect the sound much? Is it worth buying something fancy like: this polystrene or this paper in oil capacitor

I'm sure some caps in mouser would do the job. But happy to pay a few euros extra IF it does the sound well. If I order them on ebay I would get a few and I'm happy to share them for shipping costs with others (I'm berlin based)..

2 - TUNING - I read a lot that it's hard to tune it right. I saw one suggestion to change the 100k pots with 50k pots. Do people have experience with this? Or is there another easy mod (with a switch?) to get 2 different ranges... I would like to not lose the range. But still be able to dial in a bit more if needed.

3 - CHASSIS GROUND - I'm gonna build a wooden enclosure. Is it wise to use copper tape for the inside to get some shielding? Do I connect the ground to this (chassis ground)? Grounding problems are a bit of a mystery for me still. And I have quite some grounding problems (interfering with light dimmer etc) in my studio.

I guess that's it for now. Will probably be back along the way with more questions :-)

Cheers!

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Re: Soma - LYRA-8 DIY Kit

Post by wrentema » Sat Dec 12, 2020 5:12 pm

Evicshen wrote:
Sun Jul 26, 2020 3:28 pm
LegWyne wrote:
Fri Jul 24, 2020 9:43 pm
Evicshen wrote:
Fri Jul 24, 2020 4:48 pm
lyra1uf.jpg
Seriously?! These 1uF caps are missing from the BOM too!? I'm going to post my spreadsheet of discrepancies once I'm done putting together this kit.
Much appreciated! About to get my order together for this. This thread has been so necessary
Here is my digikey cart of all the resistors and caps including the missing caps and sans the extraneous 62k resistor. I got one or two extras of each component. Only some of the IC's and transistors are included in this cart.
https://www.digikey.com/short/zb1bt4

Here is a spreadsheet noting discrepancies, things highlighted yellow just notes for myself telling me that I've soldered those parts:


Please let me know if I've missed anything. Still waiting for pots in the the post, so my kit isn't complete yet.
Hey this is of great help. Thanks. I do see that 62K resistor in your BOM and I don't see it in the original BOM and on the PCB (I might miss it). Are you sure it's needed?

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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Sun Dec 13, 2020 8:52 pm

Looking at your BOM...

The 36K resistor is next to the 4093 below the soma logo. They control the rate of the vibrato for each voice.

When you are ordering, try rounding resistors (and some caps) up to 10 units...often 10 will be cheaper than 8, or 25 cheaper than 14...you get the idea. Also, order extra 5.1 ohm resistors. If you connect your polarity or ground wrong when you are testing, you will pop the 5.1 ohm resistor near the mounting leg on the lower left of the main board. I fried two in testing before I found a long bit of copper strand caught in a washer, shorting out the 5.87 V power rail.

I'm about to start my 3rd build, and I plan on updating the BOM with some of the upgrades, etc. Remember that you want an MTS-103 for the AND/OR toggle (says 102 on the silkscreen and on the BOM) to reflect the way that Soma builds their factory Lyras.
Also don't forget to ground things really well, such as the vibrato and feedback toggles, which are NOT well grounded on the PCB.

Great to see new builds!
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Re: Soma - LYRA-8 DIY Kit

Post by wrentema » Mon Dec 14, 2020 9:52 am

I'm trying to order those DIN 653 knobs. They're crazy expensive if you just order 16. Did a bit of maths.. If I order for 5 kits. I can get them for 12 Euro per kit (+ shipping). That's doable.. Is anybody interested in sharing? I'm Berlin based..
Let me know!

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Re: Soma - LYRA-8 DIY Kit

Post by grm » Wed Dec 16, 2020 9:51 am

Flounderguts wrote:
Sun Dec 13, 2020 8:52 pm
Remember that you want an MTS-103 for the AND/OR toggle (says 102 on the silkscreen and on the BOM) to reflect the way that Soma builds their factory Lyras.
Also don't forget to ground things really well, such as the vibrato and feedback toggles, which are NOT well grounded on the PCB.
oh, first time i read the about the 103 AND/OR toggle, i have a 102 in my build, but am curious what the middle position would do. can you tell, i might put in a 103 based on that.

and about the grounding of the other switches - how is that best done?

thanks in advance.

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Re: Soma - LYRA-8 DIY Kit

Post by gnsk » Wed Dec 16, 2020 10:02 am

grm wrote:
Wed Dec 16, 2020 9:51 am
oh, first time i read the about the 103 AND/OR toggle, i have a 102 in my build, but am curious what the middle position would do. can you tell, i might put in a 103 based on that.
middle position -> no connection LFOs to mod source in voices.
It has no affect to delay mod. Delay mod uses always AND, when LFO is selected as mod source.

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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Wed Dec 16, 2020 11:24 pm

grm wrote:
Wed Dec 16, 2020 9:51 am

and about the grounding of the other switches - how is that best done?

thanks in advance.
There's a post about it a few pages back in this thread. I think I put a link to it in the resources section at flundrton.com
Basically, just run a wire from the bushing or metal body of the FB and Vibrato switches to a ground point INSIDE the synth...not to a chassis point outside of the 5.1 ohm connection.
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Re: Soma - LYRA-8 DIY Kit

Post by grm » Thu Dec 17, 2020 4:04 pm

middle position -> no connection LFOs to mod source in voices.
It has no affect to delay mod. Delay mod uses always AND, when LFO is selected as mod source.
thank you. not sure if i understand the use of this function.
is the connection of LFO to voices not selected by either the voices individual 103 mod toggle or by plugging something into the CV VOICES jack already?

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Re: Soma - LYRA-8 DIY Kit

Post by grm » Thu Dec 17, 2020 4:06 pm

There's a post about it a few pages back in this thread. I think I put a link to it in the resources section at flundrton.com
Basically, just run a wire from the bushing or metal body of the FB and Vibrato switches to a ground point INSIDE the synth...not to a chassis point outside of the 5.1 ohm connection.
thank you, again.
will do that and hope for some solution of the LFO ticking to implement as well. i saw you have been experimenting with it.

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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Thu Dec 17, 2020 6:27 pm

grm wrote:
Thu Dec 17, 2020 4:06 pm
thank you, again.
will do that and hope for some solution of the LFO ticking to implement as well. i saw you have been experimenting with it.
And it's snowing!

Which means I have all day tomorrow to mess with the low power LEDs and non-TI versions of the 4093 that arrived today!!

Interestingly, I watched the Hainbach video of the Dust Collector. When he unplugs the LFO at 7:19, it makes the exact same clicky bleedy.

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Re: Soma - LYRA-8 DIY Kit

Post by Stoneyards » Sun Dec 27, 2020 3:01 pm

Success!

Just wanted to document the two troubleshooting steps I had to take to get it running, since not having the schematic is really a pain.

1) Channel 4 wouldn't trigger unless the envelope switch was set to "slow". I fixed this by swapping out a faulty dupont jumper cable.

2) Channel 7 did trigger - but it didn't trigger its own voice (the tuning knob for 7 had no effect.). I heard voice 8 bleeding through at low volume. When the LFO was enabled for channels 7/8, I heard LFO popping sounds coming through voice 7 when its envelope is open. I fixed this by reflowing the SMD 4093 for voices 5-8.

I wanted to make sure the stock Lyra worked perfectly before wiring up the expansion panels. Onward!

IMG_1275.jpg

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Re: Soma - LYRA-8 DIY Kit

Post by Ulleks » Sun Dec 27, 2020 4:54 pm

Hi everyone. I'm building a lyra using the official mouser cart from the guide. I'm having an hard time to distinguish the 2 types of 10u electrolytic capacitors, polarized and unipolar. Which one goes where?

I guess, this goes where I have + and - on the pcb
https://www.mouser.it/ProductDetail/667-ECA-1EM100I/

and this goes where I DON'T have + and -
https://www.mouser.it/ProductDetail/667-ECE-A1VN100U/

A confirmation would be helpful!

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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Sun Dec 27, 2020 5:36 pm

You've pretty much got it.

If it helps, all the unipolar caps go in groups of four next to the TI 4093 chips.

BTW, I think there might be a few errors in the official guide.
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Re: Soma - LYRA-8 DIY Kit

Post by mutronic » Wed Dec 30, 2020 2:17 pm

I have some general front panel questions.

What is the average thickness of the front panel? And are there dimensions or a dxf file anywhere to get an individual panel of the input/output board?

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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Wed Dec 30, 2020 10:36 pm

The ones I make are from 1.6 mm FR4, but they are probably closer to 1.75 mm with the copper and soldermask. The limiting factor is the height of the threaded bushing on the potentiometers and switches you choose. If you used really tall ones, you could probably tank up a 1/4" panel!

The reason I opted for the FR4 in that thinner style was cost and the fact that with the control pcb there are two layers of pcb sandwiched between the pot body and the nut.

There should be dxf files on the flundrton.com website. If you can't find the one you need, let me know and I'll make sure it gets posted.
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