GSSL HELP THREAD!!!

[Gustav]

No didnt see it, where would that be?

Always check basic supply voltage first when trouble shooting. If this is a board with this omission, you are not getting supply the one VCA and some ICS.

Really sorry about this - I thought the markings were solid, and since it seems they are not, this could be a problem for others as well.

Gustav

 

[Clexxx]

Thanks Gustav. Works now!

 

[Clexxx]

One more question though.
The compressor works but sometimes i get crackles only on the right channel and then followed by noise. i have to switch the compressor off and turn it back on again for it to work again. this happens from time to time.  anyone had this problem before?

Edit: Realised one more thing. The compressor doesnt get any power over night. when i switch on the power the next day the right channel wont put out anything. when i turn the compressor of the right speaker gives me a funny ballon sound ( the sound when you pinch the opening of a balloon and release air) for a second. the more i turn the compressor off and on again the shorter this sound plays, when eventually the right channel works again, yet i get the crackling sounds more often.

 

[Gustav]

One more question though.
The compressor works but sometimes i get crackles only on the right channel and then followed by noise. i have to switch the compressor off and turn it back on again for it to work again. this happens from time to time.  anyone had this problem before?

Edit: Realised one more thing. The compressor doesnt get any power over night. when i switch on the power the next day the right channel wont put out anything. when i turn the compressor of the right speaker gives me a funny ballon sound ( the sound when you pinch the opening of a balloon and release air) for a second. the more i turn the compressor off and on again the shorter this sound plays, when eventually the right channel works again, yet i get the crackling sounds more often.

First off, check voltages on all ICs/VCAs.

Gustav

 

[Clexxx]

First off, check voltages on all ICs/VCAs.

Gustav

Okay: Here are the results:

Right VCA:
That2181B to GND: 15V
NE5534: 30V

Left VCA:
same

The other  2 NE5534s: 30V
NE5532s: 30V

7915: 15V
7815:15V
7812: 12V

79L12: 12V
78L12: 12V

Other That2180B to GND: 12V

TL 072L: 24V
TL 074CN: 24V

Hope i measured them correctly.

 

[gyraf]

You need to read this thread about finding errors, how to fix them, and how to measure. Remember that this is not a help chat, but an archive of possible problems and related fixes - and you are expected to read before asking new questions (!)

Jakob E.

 

[Clexxx]

You need to read this thread about finding errors, how to fix them, and how to measure. Remember that this is not a help chat, but an archive of possible problems and related fixes - and you are expected to read before asking new questions (!)

Jakob E.

Ok So I read through a dozen of pages and learned to measure them correctly. I'm still new to this, but i guess i figured it out. The voltages schould all be correct (as seen above), right?
I havent found a similar problem in the smart search, where anyone had the same problem, where it works and after some time one channel (or more) crackle and get noisey. after a while however (or switching it off and on again) the problem resolves itself only to occur again after a while.

BTW: I filmed the error with the balloon sound if you want to hear something funny. in this case the right channel wont put any music out, however, after some time the right channel will eventually work only to expierience the crackling described above

https://youtu.be/3ZdFsAWToEI

EDIT: I made a wiring mistake, i confused the left and right channel. the left one has these problems.

 

[Potato Cakes]

Pull all of your op amps and see if the noise is present without them. If not, add them back one at a time till it does. Keep note of which one goes where so the same op amp goes back in the same place for testing. Follow along with the schematic as you go and to help pin point the problem.

Thanks!

Paul

 

[Clexxx]

Pull all of your op amps and see if the noise is present without them. If not, add them back one at a time till it does. Keep note of which one goes where so the same op amp goes back in the same place for testing. Follow along with the schematic as you go and to help pin point the problem.

Thanks!

Paul

I can try that, but since its a temporary problem this might be a little problematic.
btw noob question:  can i just pull the op amps while the device is turned on? since only the left channel is affected I would only need to pull the op amps involved in the left signal chain right?

 

[Potato Cakes]

Back to what Jakob was saying, things like powering off a unit before pulling op amps is something that is assumed that the end user knows, especially when building something that is at the difficulty level of a GSSL. The problem being temporary is a little harder to diagnose, so you're going to have to figure out how best to monitor audio to catch it when it happens. That's part of the pain of DIY. This is a long thread, but all the information needed to know how to trouble shoot is in here.

Happy hunting...


Paul

 

[Clexxx]

I'll try a different approach and swap out  the op amps to see if the problem then occurs on the other channel, will repost here if i got any results.

Edit: It's not the Op-Amps neither on it the in- or output section, not on the vca's, what kind of component could cause temporary crackles? 
Got a tip that this could be a defect capacitor. Will report back if i manage to find out which one. the one 100uF on the right bottom side appears a little domed, will check that one first

 

[Clexxx]

Sorry I have to bump this

I replaced the domed capacitors.  no changes whatsoever

A member of the forum said it sounds like a discharge of a power supply capacitor. now i just need to focus down which one, but I'm rather clueless.

Here is the sound it makes when the left channel doesnt work and i switch it off:
http://www117.zippyshare.com/v/ZNceWD7D/file.html
here is the sound when the left channel for some reason works but crackles and is noisy:
http://www117.zippyshare.com/v/wHjOsaJm/file.html

 

[gnolnos]

I have finished soldering my first DIY project. Everything in place (exclude cleaning after solder). Power it but I don't have signal out on 2 channel. Just remove 3 2180B and I found that the left VCA has none -15V on pin 5. Double check the solder connection, I've found that the link beside the 2 47K has connect to a blank. I has them connect like the schematic, power it, and done.
P/S: Sorry for my bad English.

 

[gyraf]

Read previous question about similar problem (!)

 

[Clexxx]

I think I might have solved my problem. it wasnt the fault of a capacitor. i guess it was the jumper gustav mentioned, i had soldered it on top of the pcb, for cosmetic reasons i  resoldered it to the bottom and now the comp works. besides that i resoldered some solder joints that didnt look too pretty.
whatever it was, its gone now

thanks to anyone of you guys and sorry for my noobness

 

[gyraf]

*like*

 

[up_right]

Hello Everybody,

I built a GSSL about 2 years ago with the sidechain mod. It has been working great.... until....

I turned it on and the LED was off. Audio passes through with no distortion, but none of the controls work.

Any help would be extremely appreciated.

Cheers!!!
T.

 

[Gustav]

Hello Everybody,

I built a GSSL about 2 years ago with the sidechain mod. It has been working great.... until....

I turned it on and the LED was off. Audio passes through with no distortion, but none of the controls work.

Any help would be extremely appreciated.

Cheers!!!
T.

Almost as if the 10 pin connector for the control board magically jumped out of its socket..!?

Could you check connections to the control board, and the 12V supplies?

Gustav

 

[up_right]

Almost as if the 10 pin connector for the control board magically jumped out of its socket..!?

Could you check connections to the control board, and the 12V supplies?

Gustav

Thanks for the quick reply. Will look into that and get back here with news. Thanks again.

 

[Gustav]

Hey guys. I didnt think i'd would be that quick I'd be back.  sorry.

After i fixed the other problems everything seemed to work, but the next i turned it on and for like 30 seconds i didnt have compression when it suddenly kicked it and worked for the rest of the day. from that time on the timespan where it wouldnt work always got longer and now it doesn't compress at all. Makeup Gain works though and the voltages are all fine.

Do you have some pictures of the soldering work? Bottom of the main board, backside of control board, connections to the pots and bypass switch etc.

No 10MB pictures, but enough to to actually see the soldering work.

Gsutav