GSSL HELP THREAD!!!

Thank you Gustav! I will use the PCB for my main reference.

Just to double check, caps marked with "1" on the PCB are actually 100nF (or 0.1uF). Is this correct?

Also, has anyone used the V2181L from Cool Audio as a replacement for the THAT2181 in this circuit? Seems like they are more readily available (at least in the US).

earthsled said:

Just to double check, caps marked with "1" on the PCB are actually 100nF (or 0.1uF). Is this correct?

Click to expand...

Correct..

Gustav

they're actually marked ".1" 

I took the plunge and I'm finally starting to build one of these things.  The GSSL kit arrived and everything is tested and correct. I'm in the position of buying a power transformer right now and it's been surprisingly difficult because not many other people have asked about it (or maybe they have, this thread has over 300 pages with no search function).  Anyways, this transformer should be fine, but I want to make sure before I order it. Also, does this typically come with mounting hardware or do I have to get that separate? Thanks!

http://www.mouser.com/ProductDetail/Triad-Magnetics/VPT30-830/?qs=sGAEpiMZZMvwUzoUXIIvyTw34uqMHR%252bu1eAUpPnRIZ4%3d

aaruel said:

this thread has over 300 pages with no search function). 

Click to expand...

Theres a box with the words "smart search" in the top of this window on the page. It contains search to the thread you are standing in.

aaruel said:

Anyways, this transformer should be fine

Click to expand...

Correct

Gustav

Gustav said:

Theres a box with the words "smart search" in the top of this window on the page. It contains search to the thread you are standing in.

Click to expand...

Aha, you are right. I just signed up and didn't see that when not registered  .

Also, thank you for your reassurance.

Alright - new developments in my case. Last I posted we were getting 18v off the transformer, and after a few successful power-ups a resistor burnt and it no longer powered up. I was reading my meter incorrectly and thought I was measuring 55v at the 15v rails after this incident, but it turns out it's actually reading 55mV. I re measured the power off the transformer and it's still 18v. Double checked the rectifier, and while it is oriented correctly, I'm getting the same reading of 55mV off the rectifier output pins. It sounds like it's time to replace the rectifier, but I have a feeling that was not the issue all along. Someone on the previous page mentioned I may have my bypass switch wired incorrectly. I'll look into that, but could that have caused all these issues? Thanks everyone for your time.

Hello from France everyone,

It seems to me that my gssl doesn't have exactly the behaviour it should have while tweaking attack and release switches.

I used Harpo's Guide p210 of this thread ( thank you man ! ) and my measurement doesn't match his.

I feed both inputs with 1V RMS 300Hz sin, and have right measurements for NE5534 output.

But TL072 and 74 measurements are lower than expected. For instance TL074 pin8 with release in 4th position will measure about -2.17V at slowest attack and up to -2.75V at fastest attack...

Make up gain and threashold are working fine. 12 and 15v rails are ok.

Thank you in advance for your time.
Florian

hi guys - is there a schematic for the turbo mod available anywhere? I can only find the kits...

I found illuminated push-button. Can I use the same type for the power and the turbo switches?
It is SPDT - 1NO / 1NC (off/on) with max voltage/current 250VAC / 5A , 125VAC / 8A , 250VDC / 0.2A , 24VDC / 6A.

these are not cheap and I don't want to buy the wrong component, confirmation will help!

Thanks,

Tom

Hello guys!
I've been lurking this tread while building my first  piece of gear ever.
Today i finally finished building  the GSSL and finally got the courage to power it up.
Yay the meter lights up and no smoke , so far so good right?
Nope  :-[ It is not showing compression or letting audio through.
And it's behaving VERY weird. When i turn up the makeup gain the lighted buttons slowly start to dim  :-\  When compression is off light on main switch is also off? And the GR meter starts peaking, when max gain is reached the meter and lights suddenly drop dead?
Sound like i made some giant ****up ?
Where do i start troubleshooting...
First of all thank you very much Gyraf, gustav and groupdiy folks!
This forum has been very helpful and entertaining so far
I hope to save this build and get it working, i was so excited with my first piece of gear 8)

Hi . I'm trying to build gssl with turbo mode. Is my diagram corect as I understand it ?   

Hi,

New to the forum. I completed a GSSL clone years ago with Turbo mod. I recently started messing around with calibrating the unit. Was able to get my ratios close. After much testing and adjustment I changed out the 127k resistor with a 122k. My 10:1 is spot on, while 2:1 and 4:1 are a small margin off.

After much searching I haven't found a clear answer on adjusting the ratios individually.

Would adjusting the values of the resistors for 4:1 via 1M8 and Ratio 2:1 via 3M9 nearest the ratio switch work to dial those individual ratios closer to spec?

Any direction much appreciated.

...absolute precision of the ratios are really not important in any way...

Jakob E.

If I wanted absolute precision of the ratios where would I look to further adjust those values individually?

Thanks

I'd quite like an answer to that too; actually what I would really like is a sweepable range; but I'd settle for being able to adjust the standard ones, to ones I use more frequently

Nashville said:

If I wanted absolute precision of the ratios where would I look to further adjust those values individually?

Thanks

Click to expand...

http://groupdiy.com/index.php?topic=59576.msg781790#msg781790

Gustav

Hey guys,

I'm finishing my first Gssl (mic&mod) and I just added a super sidechain mod.
Everything is connected the same like the picture below from an earlier thread.
I used 3x THAT 2181C on the gssl and changed all resistors based on THAT's datasheet.
First I tested the Gssl (standard) and it was responding as expected.
Now with the super sidechain.. no compression, it behaves like it's bypassed.. 
Only the makeup gain is responding well.

Hope someone can help me out with this or recognize this problem.
Are these symptoms of broken VCAs ? Checking the wires and connections over and over again.

(please ignore the "help" wire, it's connected in my case)

Greets from Belgium.

Hobbyist said:

.. or recognize this problem.

Click to expand...

Wrong thread, but your problem is interupted signal flow from your left side "X"

edit: Please disregard reply. I was referencing another filterboard (there are so many different ones for this project).

Hobbyist said:

Hey guys,

I'm finishing my first Gssl (mic&mod) and I just added a super sidechain mod.
Everything is connected the same like the picture below from an earlier thread.
I used 3x THAT 2181C on the gssl and changed all resistors based on THAT's datasheet.
First I tested the Gssl (standard) and it was responding as expected.
Now with the super sidechain.. no compression, it behaves like it's bypassed.. 
Only the makeup gain is responding well.

Hope someone can help me out with this or recognize this problem.
Are these symptoms of broken VCAs ? Checking the wires and connections over and over again.

(please ignore the "help" wire, it's connected in my case)

Greets from Belgium.

Click to expand...

I had the same problem. Standard gssl was working. Added the super sidechain, no compression. Only passing audio. I solved my problem by soldering all the wires to the bottom side of the ssc board (just as all the other components). Hope this helps, let me know.

Milan