GSSL HELP THREAD!!!

[tongenerator]

i used to have trouble to... but it was more because i did forget to mount some pots and switches...

but before i figured that.. i tried to troubshoot in a diffrent way...
i tried to follow the route of the audio signal on the pcb...
of course the audio has to go some way out the ne 5534... so i
followed the route along the pcb....

connect the  minus of the gssl output on to for example headphone...
then use a wire or pin and connect it to the tip / plus of the headphone...
be carefull not to touch the plus 15 volts of any chips or so...

just hold the wire there where the audio should be, like on the input
and the Output of the NE... from there u can trace it down...

U schould have a signal at the Pin 1 of the VCA and also at the 2 resistors *47K
at the right upper side of the vca things... Tracing the Audio signal down
at the PCB works, but be careful not to short something or touch the 15 Volts.
Dont blame me when u screw it up  ;D

I would give u more deatils about the Pins and Point where the Signal schould
flow... but i cant remember now... i would have to do it my self once again...
but u need to have signal at the NE5534 at the Input and in the VCA Circuit
and on Pin 1 at the That Chip.

in my case i could figure that the signal was going somewhere (*47K Resitors) but
did not reach the VCA PIN1... well i did not mount all pots on the controll thing

 

[intellijel]

I studied and traced through the circuit very very carefully. I can now say that I understand the circuit pretty well (and it is nicely explained by Gyraf).

Based on the behaviour I was seeing, I was convinced something had to be wrong with the TL072 stage. Sure enough I finally saw that I had a 560K resistor in place of a 56K feedback resistor!
Now the unit seems to be compressing in a more normal way. I still need to calibrate the meter....

 

[stereokillah]

great news intelligel , the soluion is always here, wich vu meter have you, which fsp?

 

[intellijel]

I have the cheap Farnell meter designed for the Purusha cases. The movement is terrible on these and does not give me much information.

Overall I am finding the compressor ok but very subtle. I am hoping it is supposed to be this way (since it for stereo bus and not so much for extreme use) but I guess I was expecting more dramatic ranges with it.

Is there anywhere that is showing demos of audio before and after? I would like to confirm that mine is functioning as expected.

Especially disappointing for me is the SSC board. The TL and TM modes are not doing anything interesting at all on my system but I read some posts where people raving about how much of an essential difference they made.

 

[warpie]

intellijel,

I uploaded 3 examples.
1) original sound (uncompressed)
2) thru gssl in turbo mode
3) thru gssl in 'original' mode.

The compression settings are pretty extreme. Sorry for the mp3 format but you get the idea of how a ggsl (or at least mine) sounds.

http://rapidshare.com/files/260263219/Archive.zip.html

PS Not sure how to upload mp3s here, thus the rapidshare link

michael

 

[stereokillah]

intellijel
this difference is very important when the compression is very important on mix where there is all frenquencys

so wich is th fsp amperage of your vu meter ( amperemeter )

 

[intellijel]

intellijel
this difference is very important when the compression is very important on mix where there is all frenquencys

so wich is th fsp amperage of your vu meter ( amperemeter )

I think it is 100uA

 

[osterchrisi]

Hey guys, I have a "funny" problem with my power LED: Sometimes (more or less always) when I put the unit on, the power LED doesn't light up. Then I turn the unit off and on again and: There's the light! It seems that the longer time the GSSL wasn't on the more likely this problem is to occur, but I'm not sure about that.

How's that possible? I mean there's not much stuff in front of the LED... could it maybe be that it's one of the small caps after the +12V power rail?

 

[3nity]

that LED its powered by the 78L12 so i'd change it!
Maybe a bad regulator there!

good luck.

 

[onlymeeee]

How much other stuff are you powering with the 12V rail?  relays/other leds etc?

 

[Harpo]

i used to have trouble to... but it was more because i did forget to mount some pots and switches...

but before i figured that.. i tried to troubshoot in a diffrent way...
i tried to follow the route of the audio signal on the pcb...
of course the audio has to go some way out the ne 5534... so i
followed the route along the pcb....

connect the  minus of the gssl output on to for example headphone...
then use a wire or pin and connect it to the tip / plus of the headphone...
be carefull not to touch the plus 15 volts of any chips or so...

just hold the wire there where the audio should be, like on the input
and the Output of the NE... from there u can trace it down...

U schould have a signal at the Pin 1 of the VCA and also at the 2 resistors *47K
at the right upper side of the vca things... Tracing the Audio signal down
at the PCB works, but be careful not to short something or touch the 15 Volts.
Dont blame me when u screw it up  ;D

I would give u more deatils about the Pins and Point where the Signal schould
flow... but i cant remember now... i would have to do it my self once again...
but u need to have signal at the NE5534 at the Input and in the VCA Circuit
and on Pin 1 at the That Chip.

in my case i could figure that the signal was going somewhere (*47K Resitors) but
did not reach the VCA PIN1... well i did not mount all pots on the controll thing

You will not have a signal to listen to at VCA Pin 1 and 8. These VCAs are current in/current out devices.
When using a headphone to trace-listen, there should be a headphone amp to drive this load. With gssl 0V connected to sleve of headphone amps TRS input plug, a poly cap at the front end of your test lead connected to headphone amp tip will prevent this amp from blowing by mistakenly tracing a supply voltage.

 

[osterchrisi]

How much other stuff are you powering with the 12V rail?  relays/other leds etc?

Nothing else.

that LED its powered by the 78L12 so i'd change it!
Maybe a bad regulator there!

good luck.

Is it possible that a 12Vreg behaves like that?
But would be a reasonable attempt to change that regulator in the first place, you're rite...

 

[hotbaby]

...even finished my second g-ssl and it doesn´t work  :'(
did a great solder work, no shorts... all parts are are on the correct place. Power wiring is ok. -15 +15v is all right.
I can power it up, the meter bend down to under 0. Sometimes if i power off i can hear very short the music i feed it with...
Wiring from front board to main pcb is correct. i think theres a bad part anywhere... and I just wanted useing this comp for the next vocal session this week  :'( :'( :'( wuhaaa.
will check the front board today for bad parts and hope finding the error there... or do you have any other ideas? As the meter bends down on start up there seems to be
a bigger problem... i disconnected the meter that it doesnt damage.
[ADD] And sorry for my second help thread here, i did all doing it just right but the ssl project seems to let me suck the second time :-\

 

[hotbaby]

OK for all who have a similar problem. Seems that i figured out a wrong shipped part.
I got two 78L12 instead of one 79L12. On the Envelope was labeled 79L12... bad catch!
I will get the right part soon and am shure that there was the problem.

 

[intellijel]

intellijel,

I uploaded 3 examples.
1) original sound (uncompressed)
2) thru gssl in turbo mode
3) thru gssl in 'original' mode.

The compression settings are pretty extreme. Sorry for the mp3 format but you get the idea of how a ggsl (or at least mine) sounds.

http://rapidshare.com/files/260263219/Archive.zip.html

PS Not sure how to upload mp3s here, thus the rapidshare link

michael

thanks for doing that!!  I can't get my gssl to sound like yours on the extreme settings..... hmmm perplexing!

 

[audiophreak]

Hi All,
      I ran across a thread somewhere in here that had a link to a dual deck Lorlin switch for use with 2 super sidechian filters and the Turbo board, I should have marked it, but didn't, and now I cant find it, and I've looked at Newark and cant seem to locate it.

    If anyone can point me in the right direction it would be greatly appreciated.

Thanks,
          Chip

 

[tgauge]

Hello everyone... First GSSL build.  Somewhat of a newb...

Starting the build and ran into a few questions hopefully someone can answer for me...

I found this picture and it makes total sense to me except...

1: Would the xlr inputs run to both relay and also the GSSL inputs?

2: If so, when bypassed wouldn't you see gain reduction because the GSSL would still be functioning except the audio out would be coming straight from the xlr ins?

3: Where specifically (diagram of PCB if possible) would I get my power from for the relays?

4: Where might I be able to get my hands on those beautiful little hex nuts that the original SSL uses on the front panel?

I think that's it for now... I'm sure something will pop up the farther I get into this.  Thanks guys!

 

[tgauge]

I may have answered at least one of my questions here, someone please correct me if I'm wrong...

All I actually would have to do would be flip on the picture wherever it says "in" to "out" then the xlr in would be either sent to the pcb in or the xlr out.  That makes much more sense I think, the unit would in fact be bypassed.

Technically then the PCB out would go straight to the XLR outs and also the bypass relay right?

Still a little confused I think...

 

[pucho812]

Nothing wrong with seeking advice...  I'm stumpped/feeling lazy at the moment. I fixed one of several issues I was having with my gssl. For started I wired in the power transformer incorrectly. I got that sorted out.

But here are new issues

1. the unit has a high pitched low volume beeping sound that appears to be at 60 cycles? when no audio is present. When audio is there, The volume is good and the high pitch beep goes away. This is regardless of in or out of chassis.
2.unit controls are not functioning.
3. no audioble compression but I think that is part of number 2
Any suggestions other then

check your solder work

which I plan to do when I am a bit more focused and awake.


edit: had tl072 in backwards. put in a new one. Now I got bypass working and there is a difference when it's in vs bypass. When it's in there is a slight drop in volume but the controls still do not alter the audio. When it's out volume is unity. Slowly tracking it all down.

 

[audiophreak]

Hi All,
     
    I took page 4 of the Gyraf PDF for GSSL and copied the main PCB track layout and reversed it and enlarged it to better fit a 81/2 x 11 sheet of paper to make it easyer to check for solder bridges, ( instead of holding it up to a light source ) what a PITA.

  With Gyraf's permission, I'll post it, it helped me, and I think it may make it easier for others to check their work.

  Gyraf.... you out there ?