GSSL HELP THREAD!!!

[Harpo]

Hi guys,

I've had a GSSL change in sound over the years, as things do. Less brilliance on the top-end....

I'd suspect ears instead...

Running turbo mod, side chain mod, THAT 2180B vca's. Should I start with the electrolytics?...

... would address the opposite side of the audible spectrum, lacking low end when electrolytics loose capacitance so the hpf rises.

 

[alexsaitek]

Hello everyone, it is my first post , although I have been looking for information in this forum

First I thank the audiokitchen chef who is a very nice guy and he supplies me the pcb very fast

I have several questions about the construction of this compressor and if someone were so kind to help me

1º Question
I am going to mount that 2181A, the question is, what resistance do I have to mount in the% in the photo that I am going to put? In the main vca I have it more or less clear but in the sidechain vca I don't

(that 2181a data)
https://www.mouser.es/datasheet/2/40...et-1602487.pdf

(web where there are various data)
http://fucanay.fischerworks.com/diy/...S3HsGsqty0DXMc

2º Question
I can't find the 22uf low ESR electrolytic capacitors of 25v and I have seen these 50v ones that seem to be 5mm in diameter the same as the 25v ones, I suppose they will wipe me out?

https://www.mouser.es/ProductDetail/667-EEU-FR1H220

3ºQuestion
Do the resistors come to change the sound a lot? Since I plan to buy from the yageo brand

4ºQuestion
to make the connectors of the main PCB and the auxiliary pcb, would it be worth awg22 cable? in xlr if I am going to put mogami cable that I have here

I leave you here a list of components in case someone is worth a reference, although I do not know if it is completely fine

https://www.mouser.es/ProjectManager...0-5f2cd7ed658a

Thank you and sorry for my English from Google translator. My native language is Spanish.

 

[alexsaitek]

the new photo that uploaded from the mobile does not look good

 

[alexsaitek]

hi

The 1st question is solved, the resistance in the sidechain vca marked with% is a 47ohm resistance because I am going to use 2181. if I were to use 2180 I would not put any since pin 4 of the 2180 is removed from what I understand

The 2nd question is also solved. You should not have problems to put 50v instead of 25 because they are the same size. I only have the doubt if the brand resistance yageo are good but for now they are the ones that I am going to mount since they are the ones that I have

thank

 

[FarisElek]

Anyone know who is selling the GSSL pcb in the US? Will purchase from Europe if I have to but rather it be domestic.

Ryan

 

[Bernardo]

hi i am thinking of building a ssl 4000.
I have any questions, does anyone know where I can find the values for the adjustment of the  trim potentiometers?
Thanks a lot

 

[gyraf]

does not compute. what value?

/Jakob E.

 

[alexsaitek]

I think he means. The trims of the vca

 

[alexsaitek]

I have not finished my gssl yet, until August I do not get the 2181 from Mouser
In my case the configuration I will try to leave it as I like and the two channels as even as possible. I think with a tone at 1khz at - 18 and I think that trim affects the second harmonic

Cheers

 

[Bernardo]

exactly, you need to know what values to assign to these potentiometers to get a good compressor fit.
I would like to attach a photo but the website does not let me.
Thanks a lot

 

[Bernardo]

The potentiometers that are close to the vca Chips.

 

[gyraf]

The dist.null trimmers are traditionally 50K types feeding a 1M resistor into the dist.trim input of the VCA (if you are using the trimmable version)

/Jakob E.

 

[Bernardo]

Yes, it is the 50k dist trim potentiometer version, in which position should I put the potentiometers for a correct adjustment?

 

[Majestic12]

Yes, it is the 50k dist trim potentiometer version, in which position should I put the potentiometers for a correct adjustment?

You need to measure the THD of the unit and adjust the trimmers for minimal value.
Or feed a 1kHz sine wave into the unit and watch the second and third order harmonics on a measurement plugin or Software like SPAN.
Or just leave the trimmer in its middle position. It doesn't make THAT much of a difference in the end

 

[Bernardo]

Thank you very much majectic.Today my pcbs have arrived, in the part of vca's 2150 is inscribed, and in the list of components 2180, do I have to double the 4th pin to 2180? If I put a dbx 2150 I just have to follow the instructions in the pcb and not bend any pins?
Thanks a lot

 

[gg85]

Wondering if anyone might be able to help me with some ratio issues. I'm using 2810's. 4:1 is right on and 10:1  is very very close. 2:1 seems to be more like 3.5:1.

I've tried swapping out the 100k in the sidechain for a trimmer, and also tried swapping out the 1k's from the cv for trimmers to try and dial it in a little but neither seems to work, and instead it just messes with the 4:1 and 10:1 ratios.

I'm testing by starting with 10dB compression, and increasing the input by 10dB. When swapping out the 1k's, I only did the left channel, and unplugged the input to the right channel so it didn't affect anything.

I've installed the turbo mod and 2x Super SC boards and all are working well.

Is there something I'm missing?

 

[FarisElek]

Will someone let me know for sure as I'm having trouble finding this information. Perhaps I'm not searching the right keywods.

This is the power transformer I'm using:

https://www.mouser.com/datasheet/2/410/media-1067232.pdf

(I'm 115v US)

Right now I have:

1) Hot on the IEC going to a switch which goes to BLUE+VIOLET
2) Neural going to BROWN+GREY

which leaves me with 4 secondary wires
1) Jumper BLACK+ORANGE
2) Jumper RED+YELLOW

Now how do these attach to the PCB? I see of the 5 PSU PCB holes , the middle one goes to ground and that the two on each side are connected. Does that mean i don't need to jumper and I can just put BLACK and ORANGE on one side, and RED and YELLOW on the other?

What do I do about the 0v? Do I just attach it to IEC ground?


Ryan

 

[FarisElek]

I tried the above scenario and I'm getting 20v on orange + black. Is that okay? It's supposed to be 15v.

Ryan

 

[cyrano]

If there is no load on the transformer, the voltage will be higher. Nothing to worry about.

If you still worry, measure with a load?  ;D

 

[FarisElek]

Thanks for messaging back. I've actually done this several times and I'm very confident theoretically, but when it comes to physically doing it I always need approval because PSU's scare me.