Soma - LYRA-8 DIY Kit

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eno
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Re: Soma - LYRA-8 DIY Kit

Post by eno » Sat Mar 28, 2020 6:38 pm

I have no experience working with panel fabricators but I was wondering if they can pretty much print any kind of design ? How does that work? Is it like an overlay on metal or what ?

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Re: Soma - LYRA-8 DIY Kit

Post by whyfarer » Sat Mar 28, 2020 6:51 pm

eno wrote:
Sat Mar 28, 2020 6:35 pm
whyfarer wrote:
Thu Mar 26, 2020 9:54 am
seconding this. I looked at mouser, digikey, and tayda. tayda was by far the cheapest route
Im in the US, specifically East Coast and with the COVID-19 slowdown generally I would prefer to buy from somewhere in the US. Any preference between Mouser and Digikey ? Like perhaps one is more likely to have most of the parts than the other ?
I couldn't get my complete order off of tayda, and I finished sourcing parts from mouser. I think when I looked into digikey, I was also going to have to finish with mouser but I'm not 100% sure about that.

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Re: Soma - LYRA-8 DIY Kit

Post by whyfarer » Sat Mar 28, 2020 7:06 pm

Flounderguts wrote:
Fri Mar 27, 2020 7:38 pm
3 mm is standard metric gauge for aluminum panel. Most places stock 2, 2.5, and 3.

If your supplier isn't metric fluent, then the common sizes are .100 and .125
.090 is common, too. I'd suggest that 5052 is better for panels than 6061 alloy, but it doesn't matter much.

I think 2mm/090 might be a bit flexy, although the pcbs really stiffen it up the way it's constructed. 090 STEEL would be great, and probably easier to etch cleanly. And cheap!

My big 5u panels are between 2.5 and 3 mm, and they are plenty stiff. I regularly use 3 mm aluminum for my rackmount stuff.


A bit of a scattered reply, but I hope it helps!
Super helpful! I'll plan to proceed with 090 steel. Any suggestions on alloy? I know nothing about metal... I guess stainless would be convenient but I'm any and all suggestions.

Time to do a bit more reading about etching first

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Re: Soma - LYRA-8 DIY Kit

Post by gluepet » Sun Mar 29, 2020 4:08 pm

Just priced out the front panel at FPE and it is $150 - this build is creeping up. :moneyburn: Any ideas on nice alternatives for front panel?

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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Sun Mar 29, 2020 4:53 pm

Im in the US, specifically East Coast and with the COVID-19 slowdown generally I would prefer to buy from somewhere in the US. Any preference between Mouser and Digikey ? Like perhaps one is more likely to have most of the parts than the other ?
I'm also in the US. Here's the thing, while Mouser and DigiKey are still running, UPS, FedEx, and USPS are severely strained.
Tayda ships faster, and the parts get here faster on DHL for some reason. I'm still getting my Tayda orders in 3 days, and Mouser has been taking a week.

If you really really really want to shop USA, try Arrow...they have also been amazing at keeping their deliveries on time over the last week or two.

Also, you will probably not be able to find all your parts at one supplier, unless you fudge it a little.

I should be able to post a BOM for the expansion boards in a day or two. I finally managed to get all those switches and controls in to the space I had. I'll post some renders and stuff later on today, I hope.
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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Sun Mar 29, 2020 8:26 pm

Ok, here's an update on the expansion panel I am working on (and for 2 other people, so far)

I have finished the routing for both panels. I managed to get all those dang switches onto two 3.625 x 10 inch panels...this way, if you want to, you can get the whole shebang into a rack (which is what I plan to do.) The boards are pretty crowded, especially compared to the Lyra-8 itself.

Part of this is because I added a bazillion switches. You can now switch most of the expansion effects off, reverting each voice to the original parameters. I wanted to be able to use the Lyra in it's original form, as well. Here are some of the values I'm using. On the voice range, the original cap values are in there. For instance, on Voice 1 and 2, the original value is selected when you are on position 6.

Here is the link to the google doc that I'm keeping notes about it on...you can take a gander.
https://docs.google.com/document/d/1UKD ... sp=sharing

You will notice a weird workaround on the Vibrato potentiometers. I don't have a good source of 75k ohm pots that match the rest of the pots I'm using, so I used additional resistors to try to move the range around, so that the original values were somewhere in the center of the range. If you DO have 75k pots, then you could jumper the resistors (or put 2k resistors in all of them) and not worry about it. Again, there's a switch that reverts back to the original setting for each adjustment.

I'm just placing the values on silk layer of the boards. One other thing, Vlad's original design eschewed any through-hole parts so that the front would lay flat on the panel. I have gone to the trouble of making combo footprints for any through-hole parts, so that you can use SMD parts in their place (which is what I will do) I think it would be ok using THT parts, as long as you trim the leads close to the board, and use some Kapton tape or spacers.

I'll post a render of the first board when I get the silkscreen done.
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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Mon Mar 30, 2020 1:39 am

https://photos.google.com/share/AF1QipO ... RTSUxzRVdB

Here's a screenshot of the render on the right hand panel, which contains all the voice range switches and the vibrato knobs

Sorry about the shoddy quality of the pic...I cannot figure out how to save the render, so I took a picture of the screen with my phone :despair:
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Re: Soma - LYRA-8 DIY Kit

Post by Alfrede » Mon Mar 30, 2020 4:10 am

@Flounderguts wich software do you use? You could print in over an PDF Printer or you use a Snippettool. :)

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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Mon Mar 30, 2020 10:24 am

For this one, I'm using EasyEDA. I've been trying to switch over to Altium, but I still haven't figured out how to use custom parts libraries, and I already had the backplane parts done in EasyEDA. Unfortunately, there is no way to save pictures of the renders, and I was too tired to figure out a snip tool or something.
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Re: Soma - LYRA-8 DIY Kit

Post by whyfarer » Mon Mar 30, 2020 11:21 am

Flounderguts wrote:
Sun Mar 29, 2020 8:26 pm
Ok, here's an update on the expansion panel I am working on (and for 2 other people, so far)
I was planning to skip the tweaks, but this is looking way too cool. Plus, if I'm etching a custom panel, there's less of a reason to stay with the original format.

If you're open to it, I would also like to hop on the train and use the expansion PCBs you're designing. Happy to get in on a group buy or order my own if you release the designs. Acknowledging I don't have circuit layout experience, let me know if I can help somehow.

Also, based on your suggestion, I've ended up ordering this 090 steel sheet for my front panel. It's big enough for the extra expansion PCBs plus some extra for etch tests. 12"x24", 13 GA (.090) 304 2B Finish, 35$ shipped.

Of course, this also finally gave me an excuse to source a cheap used dremel to cut it.

I'm hoping to do a simple salt water electro etch (something like this:
Using a beeswax ground that I'll hand carve the design into: https://21stcenturyrenaissanceprintmake ... io-ground/

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Re: Soma - LYRA-8 DIY Kit

Post by musicorchard » Tue Mar 31, 2020 5:39 am

@Flounderguts - I would be happy to put in for any PCB designs for the tweak expansions that you are working on. I haven't made my voice heard here as much but I've been following your progress and it's pretty awesome to say the least! I'm not savy on circuit board design though so I can't add much advice there. I currently have the Lyra built with a FPE panel and it's sounding beautiful. Instead of building another panel for it, I wonder if I could use your PCB plans, build the expansions, and then have jumper boxes on both sides for the expansions. That way I could go for a pure Lyra sound or plug and play with the expansion qualities. Do you think this is too far fetched of an idea? Please let me know if I can help donate to your work! :hihi:

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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Tue Mar 31, 2020 7:28 pm

@musicorchard - you can totally make separate panels for the expansions. You will have to desolder some bits from your existing Lyra 8, but it shouldn't be too tough. When I have the panels done, I'll have a quote, and you can decide if you want a set.

Regarding plug and play, you might have to do some modifications for that. The panels I'm making are very dense in the way of parts, so routing bazillions of traces to box headers is a bit more than there is room for. I'm planning to have JST connector pads for each tweak, but you could easily route them into a plug. That's probably how I will do it, as I have lots of molex plugs available at work. If you made a second plug for the panel, with the original values of parts wired to it, you could have a "plug and play" expansion.
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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Thu Apr 02, 2020 1:15 pm

Ok, I think the boards are done. I removed the multi-pin headers and opted instead for wire terminals at each knob/switch. Partially because routing was getting a bit crazy, partially because I was running out of room for all the bits.

It allowed me to space the knobs out, and I think the layout is way better, now. Here are links to PDFs of the layout. I may still make changes to the silkscreen layer, but I think components are final.

Expansion A
Expansion B

Remember, this is from the backplane, so the knobs will be flipped around.

There are some funny footprints on it...the capacitor footprints allow the use of SMD or THT components, and the connection headers are for Phoenix PTSM wire terminals. I like these because you can push in a tinned wire, done! If you need to release it, a bit of wire or a small screwdriver lets you pull the wire out. There is also a pair of pin holes for 2.54 mm pins...if you want to use a regular pin male/female OR an SMD pin header, they will work on this footprint. The big squares to the sides are not circuit-connected, they just make the PTSM connector more solid.
I know the PTSM is a bit more expensive than most people want it to be (about 0.73 ea.)...which is why the options. The pads are marked 1+ 2-, but it's really only important on Voice ranges 1-4, where there are electrolytic caps in the original board.

I removed all the resistor footprints. Just like the Lyra board, I decided to make it so that you can use them as terminal to pad connectors on the switch. This makes it easier to swap them out for different values, if you find you like your Lyra tuned a certain way.
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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Thu Apr 02, 2020 2:24 pm

Price for a set of boards will be $20. I will see if I can get some cheap pricing on some of the wire connectors, as well. BOM is done, just linking part numbers, etc.

Boards will be 2 oz copper traces, ENIG coating.
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Re: Soma - LYRA-8 DIY Kit

Post by whyfarer » Thu Apr 02, 2020 10:46 pm

Looks amazing FG! I am super glad I dragged my feet long enough to catch a ride on your curtails. 20$ seems quite reasonable and I dig all the flexibility you designed into it. If you're keeping a list, please add me to it.

Just to make sure I understand, the original resistors (or something else that we may like more) will span one of the switch throws? so we either engage the original resistor, or we get the rotary? and then if we want to swap out the original resistor it's exposed on the switch legs?

In terms of panels and pcb layout, did you have in mind that these pcbs would directly abut each side of the lyra8 pcbs? I'm starting to think about my enclosure plans. I'm leaning towards leaving a bit of a gap. I don't want it to get tooooo big, but I also want easy access and comfort accessing the main controls. I'm thinking maybe a 1/2 or 3/4 inch gap?

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Re: Soma - LYRA-8 DIY Kit

Post by Alfrede » Fri Apr 03, 2020 12:18 am

Are you shipping to Germany or will there are a groupbuy for europe?

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Re: Soma - LYRA-8 DIY Kit

Post by Wavy Davy » Fri Apr 03, 2020 2:03 pm

I finished my LYRA-8 build, and am having a lot of fun playing with it.
A few notes on some mistakes, problems, and things I would do different with my build.

Mistakes:
I substituted a few caps, that were out of stock, and ordered ones that had too high a voltage, and thus were too large to fit in between other parts on the board, even though the pin spacing was correct. Had to order replacements that fit.

I put 300 ohm resistors on the [34>56, 78>12] switch, that were not suppose to be there.
It is in middle of the same row of switches, as all have the 300 ohm resistors installed on them.
Only 6 of the 7 switches get resistors, not the one in the middle.

I mounted the largest electrolytic cap (2200-25v) upright, instead of lying it down on to the board, as it should have been done.

Problems:
Some of the rainbow colored jumpers I used to connect the boards together, had defective crimps, that made no electrical connection.
So a few things did not work when I first tested my LYRA.
I recommend buzzing out (testing for continuity) every wire you use to connect your boards, before assembly.

The metal LED bezels I bought for this build, had to be cut short and filed to fit, as the control board is pressed up against the back of the front panel, making these Bezels not work well, for this application.
Still, I like the way that they look, so I might use them again in a future build.

Things I would do different:
Solder all the right angle pin headers on the Control (board with the pots/switches), so that the pins are almost parallel to the board, so they don't stick up too much.

I soldered all the pin headers, on to the same side of the component board (board with all the caps/resistors), as the components, thus covering up the silk screen writing, that tells you what signal is on each pin.
In retrospect, it would have been better to have put them on the other side leaving the silk screen visible.

Make sure all the pins face outward, away from the board, (except connector #8) so you can plug in the connectors, once the boards are sandwiched together.
There is one pin header, #8 (on the left side, looking down) that should be mounted with it's pins facing towards the inside of the board, so that it does not stick out of the side of the board, as this will affect the clearance to the case on the left side.
The #8 pin headers should face each other when the boards are stacked, so the wires don't have to go around the outside edge of the PCB.
When assembling the two boards together, connect #8 first, then place the two boards, one on top of the other, and connect the rest of the connectors from the outside edge.

Hope that helps others make a good build, and troubleshoot any problems.

A few additional build notes:
I used a recycled real estate sign, for the front panel, because it's 3.3mm thickness, made the switches stick out just right, if you left one nut on them.
The pots stuck out just right too.

I used a sheet of saran wrap, between the front panel and the particle board faceplate, for insulation. (probably not necessary).

I used 10-24 x 1/2 inch, stainless steel screws, nuts and lock washers, purchased from Lowes hardware store,
for the touch pads. These required no step washers or other insulation, as the faceplate is made of particle board.

I plan to print out a paper faceplate label, on my large format printer, and add that later.
I plan to use my 3D printer to make custom knobs (and maybe switch caps) for my LYRA, later.
I have picked out some 1/2 inch thick Walnut, hard wood sides for the enclosure, from a place called https://www.woodcraft.com
IMG_1263.jpg[attachment=5]IMG_1268.jpg[attachment=4]IMG_1266.jpg[attachment=7]IMG_1274.jpg
IMG_1266.jpg
IMG_1283.jpg
IMG_1284.jpg
IMG_1285.jpg
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Last edited by Wavy Davy on Fri Apr 03, 2020 4:25 pm, edited 2 times in total.

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Re: Soma - LYRA-8 DIY Kit

Post by Wavy Davy » Fri Apr 03, 2020 3:57 pm

Another picture of my LYRA-8 build.
This is the recycled realestate sign I used for my face plate.
I used the blank front panel board, to mark the holes.
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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Fri Apr 03, 2020 11:33 pm

whyfarer wrote:
Thu Apr 02, 2020 10:46 pm
Looks amazing FG! I am super glad I dragged my feet long enough to catch a ride on your curtails. 20$ seems quite reasonable and I dig all the flexibility you designed into it. If you're keeping a list, please add me to it.

Just to make sure I understand, the original resistors (or something else that we may like more) will span one of the switch throws? so we either engage the original resistor, or we get the rotary? and then if we want to swap out the original resistor it's exposed on the switch legs?

In terms of panels and pcb layout, did you have in mind that these pcbs would directly abut each side of the lyra8 pcbs? I'm starting to think about my enclosure plans. I'm leaning towards leaving a bit of a gap. I don't want it to get tooooo big, but I also want easy access and comfort accessing the main controls. I'm thinking maybe a 1/2 or 3/4 inch gap?
Added to list :goo:

And yes, all the resistors will span either two legs of the switch, or leg to pad. I had an epiphany about that and the caps, and removed the pads for the caps...I was doing smt to avoid pins that might contact the panel, but you can bridge contacts with a cap as well! I left in the pads for the original electrolytic caps for the voices. Vlad's older version uses film caps, so I figure that should be ok for everything else. Using THT caps instead of SMT will save most people some money, and open up more available values. You might have to do some fiddly soldering if your caps have very short legs, but I think it will be better, more flexible, and it will certainly open up a bit of real estate on the boards!

The PCBs are meant to be almost against the Lyra PCB...if you want to fit it into a 19" rack. If you want standalone, no problem. Or you can put the panels wherever you want. You could put them under or above the Lyra...Rotating the switch legs 90 deg would be easy I'm also trying to make them so that you can cut each section out, with no overlapping traces. I have put mounting holes on them, but I really don't think they are necessary, since there is a pot or switch holding it to the panel every 27 mm! For reference, they are 92.71 mm wide, and 254 mm tall.

I ran into a little snag with the 5M and 750K pots. I have some of each, so I figured they would be easy to source. Alas, no one makes a 750K pot, so we can use a 1M instead. The 16mm 5M pots are also impossible to find (even though *I* have some), and getting a 24mm pot in is difficult. I had Attack, Release Fast, Release Slow on board A (left) and Voices and Vibrato on board B, but I think I'm going to have to swap Vibrato and Attack. Which isn't as intuitive, but it fits! There isn't much real estate on these boards, so shaving 12 or 18 mm off the side is a no-go.

And yes, I'm happy to ship anywhere in the world. I plan to post the Gerbers, and if anyone wants to make them in another country, they can. They will be publicly hosted on EasyEDA as well.

I'm looking into getting a bulk buy of some of the weird parts through work. Particularly the Phoenix PTSM wire terminals. Mouser has them at 71 cents each, which is steep...but I have a rather large order going at Arrow, and I asked my rep what she could do. She has the entire BOM for the boards, and she will quote me. Fingers crossed!
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Re: Soma - LYRA-8 DIY Kit

Post by whyfarer » Sat Apr 04, 2020 8:12 pm

Flounderguts wrote:
Fri Apr 03, 2020 11:33 pm
Added to list :goo:
:sb:
Flounderguts wrote:
Fri Apr 03, 2020 11:33 pm
The PCBs are meant to be almost against the Lyra PCB...if you want to fit it into a 19" rack. If you want standalone, no problem. Or you can put the panels wherever you want. You could put them under or above the Lyra...Rotating the switch legs 90 deg would be easy I'm also trying to make them so that you can cut each section out, with no overlapping traces. I have put mounting holes on them, but I really don't think they are necessary, since there is a pot or switch holding it to the panel every 27 mm! For reference, they are 92.71 mm wide, and 254 mm tall.
Thanks for the size deets. I suppose it'll be smarter for me to wait to see how the spacing feel before I commit to cutting anything. But it's nice to think about while avoiding work on the weekends...
Flounderguts wrote:
Fri Apr 03, 2020 11:33 pm
I had Attack, Release Fast, Release Slow on board A (left) and Voices and Vibrato on board B, but I think I'm going to have to swap Vibrato and Attack. Which isn't as intuitive, but it fits! There isn't much real estate on these boards, so shaving 12 or 18 mm off the side is a no-go.
I agree - less intuitive have it switched but you gotta do what you gotta do.
Flounderguts wrote:
Fri Apr 03, 2020 11:33 pm
I'm looking into getting a bulk buy of some of the weird parts through work. Particularly the Phoenix PTSM wire terminals. Mouser has them at 71 cents each, which is steep...but I have a rather large order going at Arrow, and I asked my rep what she could do. She has the entire BOM for the boards, and she will quote me. Fingers crossed!
Getting some of the expensive parts down in price would be great, but I would buy any/all parts you're able to source for it since I already have sourced the parts for the lyra8.

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Re: Soma - LYRA-8 DIY Kit

Post by Illywhacker » Sat Apr 04, 2020 8:23 pm

Anybody help a brother troubleshoot? Have completed the build and was pretty confident of all going well so pretty disappointed to find not getting sound out from any of the voices.
- delay and distortion LFO sestions, ext-in all seem to work fine.
- self oscillates (I think that's what's happening) when Mod pot turned full.
- getting a low hum when any of the touchpads are activated. Same pitch from each.
- Tune, Sharp, Pitch, Hold all have no effect.
- Measured all the labelled test points (there aren't many) and all within +/- 10% of labelled V.

Anyone any ideas on where I should start looking or what might be the cause of these symptoms??
Needless to say I'm getting all obsessive trying to solve, but running out of theories.

Love the panel btw, Wavy Davy.

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Re: Soma - LYRA-8 DIY Kit

Post by eno » Sat Apr 04, 2020 8:27 pm

Flounderguts wrote:
Sun Mar 29, 2020 4:53 pm
I should be able to post a BOM for the expansion boards in a day or two. I finally managed to get all those switches and controls in to the space I had. I'll post some renders and stuff later on today, I hope.
I, for one, would really appreciate seeing your BOM.

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Re: Soma - LYRA-8 DIY Kit

Post by Flounderguts » Sun Apr 05, 2020 12:41 am

So I reworked the boards...good thing I'm always at home, these days!

I managed to keep the Attack, S Release, F Release on one board. The other has Voices, Delay, Distortion, and Vibrato. I'm going to go through the BOM one more time to make sure everything fits the way it should.

I opted for a highly customizable board, rather than an "easy to understand" one. It's a bit chaotic with the silkscreen, but far better than some of the builds I have on my desk right now. And I managed to cram in the 24mm 5Mohm pots for the slow release...and if anything, it looks less crowded from the knob side!

I'll get the BOM sorted straight away.
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Re: Soma - LYRA-8 DIY Kit

Post by Wavy Davy » Sun Apr 05, 2020 1:37 am

Illywhacker wrote:
Sat Apr 04, 2020 8:23 pm
Anybody help a brother troubleshoot? Have completed the build and was pretty confident of all going well so pretty disappointed to find not getting sound out from any of the voices.
- delay and distortion LFO sestions, ext-in all seem to work fine.
- self oscillates (I think that's what's happening) when Mod pot turned full.
- getting a low hum when any of the touchpads are activated. Same pitch from each.
- Tune, Sharp, Pitch, Hold all have no effect.
- Measured all the labelled test points (there aren't many) and all within +/- 10% of labelled V.

Anyone any ideas on where I should start looking or what might be the cause of these symptoms??
Needless to say I'm getting all obsessive trying to solve, but running out of theories.

Love the panel btw, Wavy Davy.
I had a few bugs with mine too, but was able to sort it out in one evening.
If you have been working on it for a long time, it is best to take a break, and start fresh the next day.

If you have used a conductive metal front panel, make sure you have an insulating layer of plastic/tape, etc., to keep the traces on your control board from shorting to your front panel.

Are you sure that all the bottom row of touchpads are connected to ground?
Measure continuity from the bottom row of touchpads, to the ground pin (-), on the power connection (back panel, with the audio out jack). Should be close to 0 ohms.
The bottom row of touchpads are all connected together, and to ground.
The top row of touchpads are not connected to each other.

Are the top row of touchpads isolated from the front panel and ground?
Use and ohm meter to measure their resistance to the front panel, and ground.
With all switches in the down position and all knobs in the counterclockwise position, the resistance to ground (-), should be 1.2 Mega ohms.
With all switches in the up position, and all knobs in the clockwise position, the resistance to ground (-), should be 3.3 Mega ohms.

If that is correct, then check for continuity on all your interconnect wires, I had a few bad crimps that kept some of my oscillators from working. Also make sure that you have not accidentally reversed any of the connectors.
Check for cold or missing solder on the connectors you soldered to the control board.

Check that all the ICs are installed in the correct orientation (the two surface mount ones are tricky, even after checking and placing them in the correct orientation before soldering, I managed to install one backwards), and that none of them have a leg bent under, and not going into its socket (it's easier to do, than you might imagine, and hard to see without prying them up and looking).
Also check that the correct IC is in the correct places on the board.
You can probably skip the PT2399 delay chips, as you indicate they seem to be working.

Make sure you have not missed any soldering connections to the pots and switches, and that none of those wires are shorted to the case of the pots/switches, which are grounded.

Without a schematic, it is hard to be more specific.
Checking the things I recommended, and a good visual inspection should get you going :tu:

If still having problems, take detailed pictures of your assembled LYRA, and then pictures of each board, and I will try to lend a hand.
Best of luck, don't be discouraged, and you will be booping and beeping in no time :wookie:

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Bjarne
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Re: Soma - LYRA-8 DIY Kit

Post by Bjarne » Sun Apr 05, 2020 2:26 am

Thanks for sharing your build notes Wavy Davy!

Is it just me, or does it look like two of the diodes on the main board are not soldered?

Cheers,
B
Wavy Davy wrote:
Fri Apr 03, 2020 2:03 pm
A few notes on some mistakes, problems, and things I would do different with my build.

IMG_1285.jpg

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