GssL 20th Anniversary edition

[Gustav]

Update 5/8-24

Schematics rev 2

PSU



Signal Path



Side Chain & Controls



Board layout

Board



We layed out the board in sections to make it logical to follow for even new builders. This makes routing quite a bit harder.

To cut down the hours needed and make sure we can keep the segregated element layout without any hassle, we routed the signal path on a single layer first with no attention to anything else. Then, we added a layer for supplies, and a layer for common ground. We couldve kept it 3 layer, but since layers come in pairs of 2, we did the 12V supplies and a few utilitarian lines on the 4th layer.

The Gyraf GssL layout features a dedicated PCB for the att/rel/ratio switches, forcing the placement of these. We decided to make sure not to limit the builders freedom to move things around and design their own front, but we added a small auxilary PCB for those switches, so they can easily mount with a connector. (the sizing needs to be checked.

Panel File

Rough panel file uploaded in the google drive folder.
We are going by the idea that youll want to pick and choose which features to incorporate, so it is just a rough draft type layout.
Endpoints for the area you can use are marked to correspond with a modushop 1RU case (We checked and double checked the measurements, but did not have one fabricated).



BOM




Reichelt BOM (sectioned)

THAT1206 Input section
https://www.reichelt.de/my/2174948

NE5534 Input Section
https://www.reichelt.de/my/2174958

VCA Drive
https://www.reichelt.de/my/2174964

Signal Path VCA
https://www.reichelt.de/my/2174966

Side Chain
https://www.reichelt.de/my/2174975

Side Chain Sum
https://www.reichelt.de/my/2174979

Blend
https://www.reichelt.de/my/2174981

THAT1646 Output
https://www.reichelt.de/my/2174988

5532 Output
https://www.reichelt.de/my/2174990

PSU
https://www.reichelt.de/my/2174991

Attack
https://www.reichelt.de/my/2174993

Release
https://www.reichelt.de/my/2174994

Ratio
https://www.reichelt.de/my/2174995

Side Chain HPF
https://www.reichelt.de/my/2174996

Bypass & Misc
https://www.reichelt.de/my/2174997


Example:5534 in/5532 & blend

Total 82,92 euros


Mouser Parts

Standard in- and output - Cart

Total 74,27 euros

1206/1646 in- and output - Cart

Total 106,81 euros


Case

1RU Case
https://modushop.biz/site/index.php?route=product/product&path=165_238&product_id=55

55 euros

Drilling up to 20 holes x 2
https://modushop.biz/site/index.php?route=product/product&path=263&product_id=490

70 euros

Printing (front and back)
https://modushop.biz/site/index.php?route=product/category&path=264

30 euros

Total 155 euros

TO DO

Document values for front panel (att/rel/ratio/SC).
Optimally looking for a volunteer to do the graphics and aeshetics for the panel.
BOM is missing knobs, meter, IEC, Pots and a few connectors.


PCBs

If we can spread the cost for a batch of boards, we will build one to test the design, and when doing so, we will share if any corrections are needed, and also upload the (rev 2 if needed) Gerbers for all to use at their own discretion (as long as that is not any type of mass fabrication )


https://www.pcbgrinder.com/produktside/20th-anniversary-gssl


Isak & Gustav




___________________________________



From the original post

We are stuck inside because of the rain, and we just got the idea to get started on an "Ultimate GssL"-schematic.

Mainly inspired by this - https://groupdiy.com/threads/gssl-help-thread.47/page-451#post-1152157

 

[Script]

How about some simple jumpers so builders can choose between 'on' or 'off'?

 

[sheshotel]

This sounds great!

 

[Silas]

Awesome idea, I’ve been reading through all the modifications and different additional boards and this would certainly take some of the complexity out of that. I hope you get time to make some!

 

[desol]

We are stuck inside because of the rain, and we just got the idea to get started on an "Ultimate GssL"-schematic.

Mainly inspired by this - https://groupdiy.com/threads/gssl-help-thread.47/page-451#post-1152157

Our tentative list (just drawing up the basics now)

Hard bypass.
Turbo mod
Additional ratios
SC High pass filters. (including this one - https://groupdiy.com/threads/gssl-add-on-help-thread.65232/page-20#post-1147935)
Additional release times
A footprint to choose between 1206/1646 (and equivalents) for in- and output vs the standard implementation already used.
Possibly footprints for adding the Cavendish Mod.
Possibly implementing a footprint for a colour-module (haven't looked into it at all, just a brain-storm idea).

Isak, will offer a round of boards if we have enough rainy days to complete it (He is currently saving for a gaming chair, which any proceeds will go towards).
We will also upload the Gerbers, so anyone can have their own made.

Questions.

1. Bypass ideology (An easy one to get us going)

I have made units with a hard bypass on relays, and my logic has dictated that I have the unit in bypass with the relays on, and the signal path with the relays out, just to take the relays out of the equation when were in operation. For some, this is "off", because they prefer the unit to pass audio when power is off.

Thoughts?

Gustav & Isak (Gustav's son).

Yes! Yes yes yes! All of that plus a mix/blend! I use mix/blend all the time in software. Limit (ratio) would be nice too!

 

[Script]

A footprint to choose between 1206/1646 (and equivalents) for in- and output vs the standard implementation already used.

Great idea

 

[Script]

Color module & MixBlend & Cavendish -- maybe just dedicated connections or jumpers again? Would make the main board much smaller(!) but overall easier/cleaner to add them later, if desired. Might suffice as USP?

Additional ratios, nice. Cos not so easy to retrofit, albeit just a few components.

 

[TwentyTrees]

Slots for a pair of DIYRE Colour modules is a great idea. The builder could then really tweak the box tone of their build per their needs.

Back in the day I built one of your MS-VECA units - for the uninitiated, like an SSL bus comp with variable sum/difference emphasis in the sidechain. I find that aspect really useful in terms of pushing the middle of the mix back or bringing it forward, it's subtle but very effective.

 

[scott2000]

Yes! Yes yes yes! All of that plus a mix/blend! I use mix/blend all the time in software

Weird that you mention this. Just last night I was watching Worrall's video explaining how some plugins implement this in a way that's not as efficient as it should be or at least in a way he likes to work. Never put any thought into it...

 

[desol]

Weird that you mention this. Just last night I was watching Worrall's video explaining how some plugins implement this in a way that's not as efficient as it should be or at least in a way he likes to work. Never put any thought into it...

I just mentioned it because I use it so much. To bring some natural sound back in with the compressed sound.

 

[scott2000]

I just mentioned it because I use it so much. To bring some natural sound back in with the compressed sound.

Yeah I got that. Just thought it was interesting, probably should have said that instead of weird, that I had just watched a video explaining how some plugins implement the wet/dry function in a way that can lead someone into making decisions based on volume increases instead of the actual parallel compression effect . I've never put any thought into it before and most likely adjusted things subconsciously to compensate but I honestly wouldn't know.

 

[amplexus]

The colour module idea is amazing. I like that better than the cavendish mod implementation personally. Lots of options to tweak the flavour including a DOA module so it could make the cavendish mod redundant anyway.

Plus then people can also DIY their own modules too.

 

[Gustav]

I have most of the schematic drawn up, but didnt consider the blend. On one hand, I would think its too easy to set up wet/dry in the DAW now that it matter, but on the other, we can just set it up on the PCB design, so you dont add it to the build if you dont want it.

I honestly dont know how the colour modules are set up. Do we need to implement a gainstage for it, and do we need to be able to vary gain to alter how much were putting into it?

I just found this - will look into it later.

https://www.diyrecordingequipment.com/pages/colour-designer-s-toolkit

 

[SIXTYNINER]

Yes! Yes yes yes! All of that plus a mix/blend! I use mix/blend all the time in software. Limit (ratio) would be nice too!

+ 1 about.

 

[desol]

I have most of the schematic drawn up, but didnt consider the blend. On one hand, I would think its too easy to set up wet/dry in the DAW now that it matter, but on the other, we can just set it up on the PCB design, so you dont add it to the build if you dont want it.

I have an analog system that I use sometimes. I plan to use this new GSSL with the analog system, so mix/blend will be important.

 

[znjamznjam]

I finds mix blend, relay bypass, turbo mod with sc most important. The rest is plus

 

[SIXTYNINER]

I finds mix blend, relay bypass, turbo mod with sc most important. The rest is plus

"Ready For Cavendish I-O" is also essential ; )

 

[Script]

Well aware this is not a request thread or wish list thread.

Depending on 'colour' type, might want:
1- color on comp dry only
2- color on comp wet only
3- color on both, i.e. on comp dry/wet mix

If color makes it onto the board, maybe consider option to chose btw configs as above (external relay board, six relays; rotary: Off, Wet, Dry, Mix) or hardwiring it for only one config with a jumper... Then leave up to builders again?

 

[Gustav]

Updated first post

 

[Script]

Not essential at all, but could make R161 and R169 in signal path both 20K trimmers (predialled to 15K when populating). For fine-calibration of input into VCA.