GssL 20th Anniversary edition

[gyraf]

..or 10k resistor plus (centered) 10k trimmer..

 

[desol]

Hi. Can we make this easy to complete with THAT 2180 series VCA? I'm planning on using 2180 series...which are pre-trimmed. Intermediate build with no calibration.

 

[gyraf]

2180 is just a matter of omitting the trimmer pot, iirc?

 

[Script]

It's drawn for 2180B.

 

[Gustav]

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.

Its probably better to adjust the feedback resistor - and also putting something like a 14K7 with a 500R trimmer in series instead.

Also, if its just to trim unity, I have experienced that the VCA "0" control voltage being slightly off is usually the real culprit. Maybe we should solve the problem at its root and do something in the drive circuit there instead (already being careful getting a clean reference for the 120R resistor).

To do list: Option to trim unity gain.

 

[desol]

It's drawn for 2180B.

Ok perfect. So there should be no changes on the pcb.

 

[elskardio]

Why not use the VCA's control port to fine tune the unity gain?

 

[Gustav]

Why not use the VCA's control port to fine tune the unity gain?

View attachment 133316

The VCA CTRL pin is really sensitive, so I would prefer adjusting R160 to this.

Thanks for blowing this up - that IC15B configuration looked kinda odd. Dropped it in upside down Will add it to page one for errata.

 

[Gustav]

PS - when you are asking for a trim for unity - how much are you seeing it off.

What I have seen is less than 0.1dB, so this is just to clear up if this if for the OCD crowd, who could, in theory, trim just about every parameter, or if you are seeing a general need.

I have answered about 8 million e-mails about this project, and never had a question about unity gain, other than blatant stuff like having the wrong resistor in the VCA gain circuit and similar.

 

[Script]

If main signal path is mostly THAT, off by 0.1dB max there indeed. Calib would be nice, but not essential, as I said.

Either way, good posture rather sooner than later is more important

 

[mcmuz88]

First time poster here. Cavendish, hipass S/C frequencies, 1:5 ratio add, wet/dry blend + transformer options would make this an instant buy for me. I love how Stam came up with their mods but their QC is terrible. Hence why I've joined here!

 

[electrisizer]

Im a Fan of dual mono Units, to Work in mid side Mode for mastering duties. Much better Control in this Case imho

 

[zzzzz]

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

^ agree with all of the above. On board blend is legendary.

This is all awesome! Thanks Gustav and Isak!

 

[Gustav]

Updated first post.

 

[richiyobs]

What about adding a 90 degree filter at sidechian input? Distorsion at low frequency Is largely reduced, i simulated It once with good results.... Also KA-electronic Is developping a new sidechian based on Studer filter with well explained and measured results

 

[gyraf]

a hilbert filter in sidechain would probably change the workings of this so much that it won't be recognizable as a ssl comp any more. The distortion is part of the sound, more or less. (but the filter is a great thing for clean compressors as such, works beautifully in e.g. the G24..)

 

[Gustav]

What about adding a 90 degree filter at sidechian input? Distorsion at low frequency Is largely reduced, i simulated It once with good results.... Also KA-electronic Is developping a new sidechian based on Studer filter with well explained and measured results

sound like the all mods version has some mods coming to you

 

[Script]

Buffered external send / return as an option? Or just a mention...

 

[desol]

Personally I don't care about anything but more ratio's (limit), attack/release times....Hpf, bypass and Mix/Blend. I don't care about colour option, I don't even know what it is. I'm kinda scared of it having too many 'options'. Just please, simple board with good features, good sound....no mistakes.

 

[Brian Roth]

Personally I don't care about anything but more ratio's (limit), attack/release times....Hpf, bypass and Mix/Blend. I don't care about colour option, I don't even know what it is. I'm kinda scared of it having too many 'options'. Just please, simple board with good features, good sound....no mistakes.