GSSL HELP THREAD!!!

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1 - please read/search this help thread first - it's not meant as a "help chat", but an archive of solutions: GSSL HELP THREAD!!!
2 - as stated a couple of times earlier, use any 1mA FSD meter (or a more sensitive, and adjust with the series resistor)
3 - yes, we suggest you connect gnd and chassis at the xlr input connectors
Thanks!
 
And what about the meter scale? I see some compressors meters that have a 20 to 0 db compression scale. All the meters I see are normal VU meters 20 to 3.
 
And what about the meter scale? I see some compressors meters that have a 20 to 0 db compression scale. All the meters I see are normal VU meters 20 to 3.
I have some Pico meter boards that are compatible with the gssl. I think I have 3 available. If more are needed I'll order more.

I haven't gotten around to testing them yet but same layout as the OG.

It's fully documented somewhere on the web.

PM me if you fancy a LED meter.
 
I have a silly question after a few years with my compressor. Why do I have to lower the level of my daw to -20db so that it does not saturate the input of my Gssl? does not have the input impedance of current equipment? Thank you.
 
hello gyraf, I suppose that -18db analog corresponds to 0db in digital. in my converter the outputs are set to +10db. I notice that I have to lower the output level more in the daw with the gssl than in other machines, maybe I have some input impedance problem in my gssl? thank you
 
hello, does anyone have a diagram of how to connect a regular on-off switch and how to connect the bypass? I mean the drawing... I'm having trouble with it. many thanks in advance
If you search on line for the Docs used to build PCB Grinder's kit, I think that has the info you're looking for.

If you can't find it, DM me, and I'll look for the PDF.
 
Ok, I ran my gssl and it's generally fine. All indicators on scaled circuits are correct, I checked all elements 3 times, after soldering I washed the factor and checked for a short circuit and they are fine. The problem is that when one channel plays perfectly with compression, while the other channel does not compress, it just sends the signal unchanged from input to output ... the signal is even used. I checked a lot of items but everything seems to be working fine. There are definitely no short circuits on the 12v and 15v rails because all the voltages on the NE5534 and 5532 are correct. I used THAT 2181C and they are also correct because I changed them ... and the left channel plays correctly and the right channel only sends a signal without compression.
Do you have any place where I can check...? Thanks

update: So the compressor works properly and cleanly on both channels :) but ... I discovered that it works only when one channel is connected, i.e. cables from one channel ... when I connect the other channel ... silence ... what's going on here ? Both channels and both transmission cables play separately ... but when connected together they give silence..

update: Ok, I found out what was wrong .... I soldered the wires to the xlr output wrong, the ground was on pin 2, so after connecting the two channels the signal was shorted to ground ... stupid mistake: D done ... the compressor plays very clean on two channels :)
 

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Hi Folks - just rejoined the forum - I was an active member several years ago and built a couple of GSSL, a dual REDD47, a D-LA2A, a stereo Pultec EQ, A dual Gyraf Calrec EQ, a G7 mic, and an 1176 when I was building up my own home studio.

I have been tweaking one of my GSSL and have a simple question which cannot find by searching anywhere in the GSSL Help thread so far....forgive me if I have missed it.

I'd like to add an external side chain to my current GSSL. It has an expat Turbo board fitted and the whole thing works superbly.

I noticed that there is an external sidechain input on the gyraf PCB layout.

Can I simply add a switched TRS jack on the front panel so I can patch in an external mono signal from my patch bay to control the side chain - say for ducking the mix slightly for vocals etc ?

Does the Turbo board mod affect this and what about if I wanted to use a stereo side chain inout - is that impossible ?

Thanks for any advice.
cheers
PeteC
 
Hi all, I'm about to start building my GSSL and have a question about the makeup gain.

I notice the makeup gain on SSL G384 ranges from -5dB to +15dB.

Does anyone know if it's possible to mod the GSSL makeup gain circuit (which ranges from 0dB to +20dB) to mimic the makeup gain range of the G384?

Thanks for any help.
Chris
 
Hi,

I'm building my first GSSL, but I'm quite confused about the changes I need to apply for 2180 VCAs.

Unfortunately this link doesn't work anymore : http://diy.fischerworks.com/gssl_vca.shtml

So far I sticked to the REV#11 PCB silk, but in the BOM I used to order, there were 3K9 and not 5K1 resistors, so I don't know which ones to use.

I have also mounted the two 27K* resistors at the VCAs inputs, not sure I should have.

I'm also missing two 22R resistors from the BOM, I'm guessing it's a simple mistake.

I also realized that the Turbo GSSL Mouser BOM had slighty off resistors values, like 3M92 instead of 3M9.

Is it a problem to use these slightly different values between the main board and Turbo's VCAs ?

Could anyone enlighten me please ?

Thanks,

Dom
 
Cześć,

Buduję swój pierwszy GSSL, ale nie jestem pewien, jakie zmiany muszę wprowadzić, aby ubiegać się o 2180 VCA.

Niestety ten link już nie działa: http://diy.fischerworks.com/gssl_vca.shtml

Do tej pory trzymałem się jedwabiu PCB REV#11, ale w BOM-ie, który zamówiłem, były rezystory 3K9, a nie 5K1, więc nie wiem, które zastosować.

Zamontowałem również dwa rezystory 27K * na wejściach VCA, nie jestem pewien, czy powinienem.

Brakuje mi również dwóch rezystorów 22R z BOM, domyślam się, że to zwykły błąd.

Zdałem sobie również sprawę, że BOM Turbo GSSL Mouser miał nieco inne wartości rezystorów, na przykład 3M92 zamiast 3M9.

Czy używanie tych nieco innych wartości między płytą główną a VCA Turbo jest problemem?

Czy ktoś mógłby mnie oświecić proszę?

Dzięki,

Dom
I hope this helps you, you need to correct the value of some elements and remove some completely. The table I posted shows this. good luck :)
 

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..if you want that, you can just add limiting resistors to each end of the makeup pot..

/Jakob E.

Hi Jakob,

When you say "each end of the makeup pot", do you mean add a resister between one end and ground, and another between the other end and 12V?
Or does one of the resistors go between the moving arm and the 620K resister that follows the pot?
 

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..resistors between one end and ground and between the other end and 12V would limit the range of voltage at potentiometer viper, thus limiting the voltage range added to the VCA, in turn limiting gain range. Perhaps put two trimmers in there, one at each end of makeup pot. Note: trimming one end will affect the other end too, making some back-and-forth adjustment necessary.
 
If you can't dial it in using those two trimmers, the 620k resistor too might need trimming. it defines/shifts the overall range, I think (or zero gain point, if you will).

Either way once it's dialled in, I'd replace with fixed resistors.

Let us know how it goes.
 

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