Soma - LYRA-8 DIY Kit

[gnsk]

i used DIN653 from aliexpress, and bought again expensive ones from accu.
difference is,

accu ones;
head dia D=12.35mm
head length K=2.5-2.25mm

ali ones;
D=11.7-11mm
k=4.1mm

so, ali one is smaller and thick. Thick is not so issue, but smaller touch area was some uneasy to me.

[Muthut]

Hey there !

Are there any fellow builders from germany that may care about sharing their cart or place where they sourced their components ?
Especially for stuff like the touch-plates.
And if not, international ones are also great !

It would be of tremendous help !

Have a great one !

[kitzmann]

I'm on the waiting for the PCBs so I'm starting to source the parts. Where do you get the pressure pads?

[Flounderguts]

CONTACT pads. Any bare metal will work...even a bolt!

The DIN 653 screws are getting scarce. Try computer mod shops, as they often stock thumbscrews in M3.

I have some standard panels on the way that eliminate the DIN screws in favor of gold circuit touchpads.

[fizzkakz]

Hey collective, first time poster, long time lurker. Firstly thank you for all the incredible insight and learnings in this thread. You've given me a heap of direction on how to get started on this project.

Excuse the question if it's dumb, I'm still a bit of a DIY novice. What is the rationale for using cannibalised component legs to connect pots to the pads on the control board over say, some insulated hookup wire? I thought have thought something insulated would reduce the likelihood of creating a short and would probably be less fiddley?

[Flounderguts]

Hey collective, first time poster, long time lurker. Firstly thank you for all the incredible insight and learnings in this thread. You've given me a heap of direction on how to get started on this project.

Excuse the question if it's dumb, I'm still a bit of a DIY novice. What is the rationale for using cannibalised component legs to connect pots to the pads on the control board over say, some insulated hookup wire? I thought have thought something insulated would reduce the likelihood of creating a short and would probably be less fiddley?

Welcome! Great thread to have your first post in...hopefully you will keep posting, now that the gate is open

In the case of the Lyra, the original build from the factory is built in this way. Actually, bits of component legs weren't used, but bare conductor wire was. That is also what I used for my build, as I keep that stuff around. Most people do not, so the discarded clips from builds of yore is a good source of bare metal wire.
The issue with using insulated wire is twofold...first of all, that's a lot of wire stripping! Second, most of the DIY builders aren't exactly professional soldering technicians, and it's easy to get too much heat into a short bit of wire like that...the insulation will melt off and make an ugly mess! Conversely, when using bare hookup wire, the solder wets up the leg really nicely, and makes a great connection.

I didn't say anything about the pic posted a few days ago, but I think that soldering all the leads on the pots first is way too much extra work. I suggest mounting the pots through the control PCB to the panel, and getting it all lined up first. Then solder the "legs" to the pads vertically. It's really easy if you use a pair of hemostats to hold the wire in place, so that you can use both hands to blob a nice teardrop of solder on there. Then it is really no big deal to clip the lead a bit long, and do the rest. They are quite strong, so you can take your time bending and soldering the other bits to the switches and pots nicely.

When I first started soldering the components to the wings of the expanded Lyra, I was bending a little "L" into the bottom of the leg, ostensibly to get a better mechanical join...these were actually WORSE than just standing the wire on the pad.

As for shorts, things are pretty spaced out in the Lyra. You would have to work to build in a short. Or fill the enclosure up with metal filings.

But build it how you like it! That's the whole point of DIY

[fizzkakz]

Welcome! Great thread to have your first post in...hopefully you will keep posting, now that the gate is open

In the case of the Lyra, the original build from the factory is built in this way. Actually, bits of component legs weren't used, but bare conductor wire was. That is also what I used for my build, as I keep that stuff around. Most people do not, so the discarded clips from builds of yore is a good source of bare metal wire.
The issue with using insulated wire is twofold...first of all, that's a lot of wire stripping! Second, most of the DIY builders aren't exactly professional soldering technicians, and it's easy to get too much heat into a short bit of wire like that...the insulation will melt off and make an ugly mess! Conversely, when using bare hookup wire, the solder wets up the leg really nicely, and makes a great connection.

I didn't say anything about the pic posted a few days ago, but I think that soldering all the leads on the pots first is way too much extra work. I suggest mounting the pots through the control PCB to the panel, and getting it all lined up first. Then solder the "legs" to the pads vertically. It's really easy if you use a pair of hemostats to hold the wire in place, so that you can use both hands to blob a nice teardrop of solder on there. Then it is really no big deal to clip the lead a bit long, and do the rest. They are quite strong, so you can take your time bending and soldering the other bits to the switches and pots nicely.

When I first started soldering the components to the wings of the expanded Lyra, I was bending a little "L" into the bottom of the leg, ostensibly to get a better mechanical join...these were actually WORSE than just standing the wire on the pad.

As for shorts, things are pretty spaced out in the Lyra. You would have to work to build in a short. Or fill the enclosure up with metal filings.

But build it how you like it! That's the whole point of DIY

Thanks for such a detailed response! Great insight.

[wrentema]

Hey there !

Are there any fellow builders from germany that may care about sharing their cart or place where they sourced their components ?
Especially for stuff like the touch-plates.
And if not, international ones are also great !

It would be of tremendous help !

Have a great one !

Hey I ordered to touch plates here (havent arrived yet but more people here ordered them here: https://www.aliexpress.com/item/32975169127.html Way way cheaper than ordering them in Germany..

I'm Berlin based. I ordered whatever I could from Mouser (super fast delivery, no import costs etc)
Other shops I used are
musikding.de (pots and PT2399) They're slow though...
reichelt for TDA2822
polin electronic for switches. I bought the exact same as the BOM. But I'm sure you can order the same switches (from different brand from mouser too..)

I havent tried Tayda. They seem to have good prices. But I think delivery could take a while and maybe additional custom costs..

I'm almost done with my build. I made an excel with the exact parts I used. I can share it in a few days when I'm done.

Cheers

[fizzkakz]

So I think I have all parts with the exception of the headphone jack. I'm slightly confused about what to get. The BOM isn't any more descriptive than 3.5mm stereo socket. When I look at pictures of other people's in/out PCB, I can't even see a spot for it. What am I missing here? Does the headphone socket mount directly onto a PCB or do I mount it to the enclosure and use wire to get the signal back to the PCB?

[mutronic]

So I think I have all parts with the exception of the headphone jack. I'm slightly confused about what to get. The BOM isn't any more descriptive than 3.5mm stereo socket. When I look at pictures of other people's in/out PCB, I can't even see a spot for it. What am I missing here? Does the headphone socket mount directly onto a PCB or do I mount it to the enclosure and use wire to get the signal back to the PCB?

I believe you wire in the DC, power-switch and headphone jack.

[Flounderguts]

Yep. There are pads marked for power and headphone jack.

I'm still stuck north of the border, but I decided (since I have a lot of time while waiting for things to happen) to buy a factory Lyra-8, and it arrived today. I'm going to pull it apart and see what the differences are between factory units and our DIY. Perhaps we will get some insights to the LFO circuit and other mysteries!

On another note, I happen to have a set of extra touchpad screws. The ones on the actual factory Lyra are 12 mm in diameter, and the ones I have are 10.5 mm diameter. There are 18 of them, and I will ship them as soon as I get back home (probably in about 10 days...I hope!)

Anyone want them? $5 plus shipping.

[Flounderguts]

Ladies and Gentlemen....

I have begun my teardown of a factory Lyra-8.

Surprise, motherfucker! It's not really the same as the DIY kits. Control and IO boards are V 3.3, and main board is V 3.4

Much of it seems to be for simplifying production...the switches and pots are NOT mounted to the backplane of the board. Instead of DuPont cables, pin connectors are used (single row male on the main board, going into double row female on the control board.

The monster pad on the IO is connected to a spade terminal welded to the case, as we suspected. There are points to mount switch and headphone out to the PCB. Most of the components seem the same, but it will take me a while to verify that...there's an inductor I don't recognize on the IO.

I don't have time right now to post pix, but I will asap. Let me know if there are any specific questions or pix you want me to take. The PCBs are still yellow, though. And there are some interesting handmade touches to it...

[Bjarne]

Interesting! I appreciate the effort.
Cheers

[deformative]

Anyone know the oscillator range caps for the current build? I have Lyra's tweaks doc for v2.2 but I have v2.6 and it looks like those capacitors have changed/moved.

[Flounderguts]

The values are the same for all builds. 1/2 is 2.2 uF, 3/4 1uF, 5/6 0.47uF, and 7/8 0.22 uF. On newer builds 1-4 are electrolytic, and 5-8 are poly film. They are identical on the V3.4 board.

[gnsk]

Ladies and Gentlemen....

I have begun my teardown of a factory Lyra-8.

Surprise, motherfucker! It's not really the same as the DIY kits. Control and IO boards are V 3.3, and main board is V 3.4

Much of it seems to be for simplifying production...the switches and pots are NOT mounted to the backplane of the board. Instead of DuPont cables, pin connectors are used (single row male on the main board, going into double row female on the control board.

The monster pad on the IO is connected to a spade terminal welded to the case, as we suspected. There are points to mount switch and headphone out to the PCB. Most of the components seem the same, but it will take me a while to verify that...there's an inductor I don't recognize on the IO.

I don't have time right now to post pix, but I will asap. Let me know if there are any specific questions or pix you want me to take. The PCBs are still yellow, though. And there are some interesting handmade touches to it...

I also the investigated factory build lyra-8 a few months ago. V.3.4. Besides physicalisch connection changes, there is other difference, that i noticed;

In two TL074s in the middle of Main PCB. DIY uses 0.047mf *Ceramic* capacitors. But factory one used *box type* caps.
The PCB trace is also different, i remember. I changed DIY version's cap to WIMA Cap, but not so different about LFO bleeding.

BTW the factory one has also LFO Bleeding, not so different with DIY's one. I bought factory one to check or compare the level of Bleeding, and checked it could be normal in two cases. Now i sold the factory one, and accept the bleedings.

factory ones bleeding video;
https://toobnix.org/videos/embed/6878ef ... 8ab11e01b0

[deformative]

The values are the same for all builds. 1/2 is 2.2 uF, 3/4 1uF, 5/6 0.47uF, and 7/8 0.22 uF. On newer builds 1-4 are electrolytic, and 5-8 are poly film. They are identical on the V3.4 board.

Ah, you're right. Found them. My fault for troubleshooting with whiskey.

[kitzmann]

In anticipation of getting the PCBs for the Lyra-8 I have been thinking about the front panel. Flundrton.com is sadly out of stock but I was able to download the gerber files from the site for free, which was decent of him. I would rather have the panel professional made, if possible. Any recommendations of outfits that could use the Gerber files to create a front panel for me? Pre-drilled and printed?

[Flounderguts]

In anticipation of getting the PCBs for the Lyra-8 I have been thinking about the front panel. Flundrton.com is sadly out of stock but I was able to download the gerber files from the site for free, which was decent of him. I would rather have the panel professional made, if possible. Any recommendations of outfits that could use the Gerber files to create a front panel for me? Pre-drilled and printed?

I actually have stock at flunderton.com...but I'm not home to unpack and inspect the panels before sending them out. I had to make a quick trip to take care of a family thing, and the 2nd COVID travel restrictions caught me a bit (I was on a compassionate waiver).

I've booked a ticket home, and I'm just waiting for confirmation and I have to get another negative test in a day or two. I'm hoping to get the green light to go home for the 30th.

If you can hold on just one more week or so, I will be able to send out a front panel for you. There are now 3 options...the one I did before but upgraded to ground the FB and Vibrato switches, a 266x266 panel with mandala-style touchpads instead of DIN screws, and a panel that fits on the bottom of a Hammond 1444-12123 enclosure. I haven't finished an IO board for the standard panel, yet. I may have time for that while I wait for flight confirmation this week.

Cheers!

[Flounderguts]

I also the investigated factory build lyra-8 a few months ago. V.3.4. Besides physicalisch connection changes, there is other difference, that i noticed;

In two TL074s in the middle of Main PCB. DIY uses 0.047mf *Ceramic* capacitors. But factory one used *box type* caps.
The PCB trace is also different, i remember. I changed DIY version's cap to WIMA Cap, but not so different about LFO bleeding.

BTW the factory one has also LFO Bleeding, not so different with DIY's one. I bought factory one to check or compare the level of Bleeding, and checked it could be normal in two cases. Now i sold the factory one, and accept the bleedings.

factory ones bleeding video;
https://toobnix.org/videos/embed/6878ef ... 8ab11e01b0

That's an interesting video. I'm not getting the same bleed on the factory unit I bought, which is even the same color as the one you had!

I noticed the different caps on the TL074 chips, but on mine they are MLCC orange drops, rather than box caps. Another difference is on the distortion cap, which is a smt ceramic cap instead of what I used, which was a poly film cap. As soon as I get back, I'm going to swap all the distortion caps for cheap ceramic caps, and see if that helps with my distortion.

The IO board on the factory one is significantly different, but I'll have to wait to get home to get a good look at how, as I don't have many good pictures of the DIY IO version with me.

Do you have any volume level issues or headphone noise on your DIY build?

[gnsk]

What volume level issues? not experienced with it. Maybe there is, but not noticed.
With headphone, there is more noise than main out, but not so big and not annoying.
I think the headphone amp chip TDA2322 is lofi itself. The datasheet says "especially designed to amplify the IR signal in remote controlled TV or radio sets. "
If it is annoying, man can bypass the chip and use NE5532, or OPA2134 headphone amp for good quality, i think.
Hope this helps.

[kitzmann]

Any chance that you will have another run of the Lyra-8 panels in the near future? I'm on the wait list for the boards and am eager to get started.

cheers!

[neilarmstrongmuseum]

I have a LYRA-4 DIY PCB (v.2.2) that I have had for years in a drawer and it is finally on my bench!
On the Main PCB there is a spot for an inductor that I can't identify in the BOM (I also appear to have the BOM and documentation for LYRA-4 v.2.0).

The inductor is connected to pin-14 of the 4016 ic (which is on the In-Out board for the LYRA-8). That tiny writing reads "24247TAX207"
I don't see this component on any versions of the LYRA-8 DIY PCBs (neither the Main or In-Out boards) that are provided on the Soma site. I've read elsewhere in this discussion that the DIY PCBs differ from the factory PCBs. Perhaps I was sent a factory PCB as I bought the kit while LYRA-4 was being phased out.

Do we know what the value should be for this inductor?

Thanks for all the invaluable info from this thread!

[rationale_music]

I have a LYRA-4 DIY PCB (v.2.2) that I have had for years in a drawer and it is finally on my bench!
On the Main PCB there is a spot for an inductor that I can't identify in the BOM (I also appear to have the BOM and documentation for LYRA-4 v.2.0).

The inductor is connected to pin-14 of the 4016 ic (which is on the In-Out board for the LYRA-8). That tiny writing reads "24247TAX207"
I don't see this component on any versions of the LYRA-8 DIY PCBs (neither the Main or In-Out boards) that are provided on the Soma site. I've read elsewhere in th is discussion that the DIY PCBs differ from the factory PCBs. Perhaps I was sent a factory PCB as I bought the kit while LYRA-4 was being phased out.

Do we know what the value should be for this inductor?

Thanks for all the invaluable info from this thread!

I asked Vlad about it back when I was putting together my Lyra-4. This was his reply:

"This is a choke 220 - 470 mkH
you need one with low internal impedance < 1.5 Ohm
Or you can easy short it if you have a good PSU"

[Flounderguts]

It is on the V3.3 IO board as well.

Great info!