GSSL HELP THREAD!!!
- Thread starter hairyandy
- Start date
Help Support GroupDIY Audio Forum:
Yes the long end of the LED is the + postive (anode end),
The shorter is the Negative (cathode end).
If your measurments at the Rectifer are not right (No DC output) I would
defintly try replacing the rectifier, it cant hurt anything.
If you have a bread board you can take your removed
rectifier and test it there and rule out any problems with the board.
Be EXTREMLEY carefull when working with AC voltages. The
one hand in the pocket rule is a good one to follow. I make
sure all my AC connections have shrink tube around them and I
wrap some electrical tape around the IEC socket and on/off switch
for good measure just in case.
The shorter is the Negative (cathode end).
If your measurments at the Rectifer are not right (No DC output) I would
defintly try replacing the rectifier, it cant hurt anything.
If you have a bread board you can take your removed
rectifier and test it there and rule out any problems with the board.
Be EXTREMLEY carefull when working with AC voltages. The
one hand in the pocket rule is a good one to follow. I make
sure all my AC connections have shrink tube around them and I
wrap some electrical tape around the IEC socket and on/off switch
for good measure just in case.
Tonight i did some measurements at the TL074. Are these values somewhat correct? My values at pin 8 seems very "lame"?
With audiosignal fed to left input with threshold pot full CCW:
TL074
pin7
peaks: -0.3 V
silence: -8.0 V
pin8
peaks: -0.28 V
silence: -0.15 V
Some time ago I mounted a TL074 the wrong way. I changed the TL074. But maybe some other components got fried at the same time during this? I haven't replaced any components besides the TL074.
With audiosignal fed to left input with threshold pot full CCW:
TL074
pin7
peaks: -0.3 V
silence: -8.0 V
pin8
peaks: -0.28 V
silence: -0.15 V
Some time ago I mounted a TL074 the wrong way. I changed the TL074. But maybe some other components got fried at the same time during this? I haven't replaced any components besides the TL074.
Hey guys,
I asked this on another thread, as some of you may have already seen. And read through a bunch of pages here but no luck. So, I repost here to see if anybody remembers anything about this problem without having to search for hours on 70ish pages of threads.
thanks guys.
here it goes:
I read through the meta and couldn't find some that explains the problem that I'm having.
I recently built 2 of these clones (SSL Comp) and both are giving me a little noise followed by a swelling sound after I change Attack and Release settings. I sounds like if the comp is taking some time until adjusting to the new settings.
I thought i might be due to shorting rotaries, but the one's I used are non-shorting. Should I have used shorting instead??
Did anybody experience the same problem? If so, did you find the answer and the fix for it??
thanks guys
Gil
I asked this on another thread, as some of you may have already seen. And read through a bunch of pages here but no luck. So, I repost here to see if anybody remembers anything about this problem without having to search for hours on 70ish pages of threads.
thanks guys.
here it goes:
I read through the meta and couldn't find some that explains the problem that I'm having.
I recently built 2 of these clones (SSL Comp) and both are giving me a little noise followed by a swelling sound after I change Attack and Release settings. I sounds like if the comp is taking some time until adjusting to the new settings.
I thought i might be due to shorting rotaries, but the one's I used are non-shorting. Should I have used shorting instead??
Did anybody experience the same problem? If so, did you find the answer and the fix for it??
thanks guys
Gil
Is it an actual problem? Our 4000E desk does that also to some extent - you'll never change the settings while recording anyway...
But yes, it may have to do with shorting/nonshorting switches.
Jakob E.
But yes, it may have to do with shorting/nonshorting switches.
Jakob E.
I've done some measurements on the TL072 and the TL074 and they both seem right. Should I measure the sidechain VCA also? I have two dbx 202xt as main vca's. How do I measure these for faults?
I would be thankful for a tip or two on this.
/Flundran
I would be thankful for a tip or two on this.
/Flundran
Greg
Well-known member
Flundran:
How's the compressor? Let me summarize to make sure I understand your problems. The compressor is passing signal, but you're getting no compression and your meter starts to move but then sticks ?!?
First, since your SSL is passing signal, I wouldn't suspect the channel VCAs to be the problem. I'd expect it to be somewhere in the sidechain. And you stated you feel the TL072 and TL074 are working properly. And just for clarity, your testing for compression by scoping the output, measuring between pins 2 and 3, not just looking at the meter.
Just something that popped in my head... did you place the small jumper on the daughter PCB? And what VCA are you using for the sidechain?
How's the compressor? Let me summarize to make sure I understand your problems. The compressor is passing signal, but you're getting no compression and your meter starts to move but then sticks ?!?
First, since your SSL is passing signal, I wouldn't suspect the channel VCAs to be the problem. I'd expect it to be somewhere in the sidechain. And you stated you feel the TL072 and TL074 are working properly. And just for clarity, your testing for compression by scoping the output, measuring between pins 2 and 3, not just looking at the meter.
Just something that popped in my head... did you place the small jumper on the daughter PCB? And what VCA are you using for the sidechain?
Greg:
The compressor is passing signal thru fine, and the meter is stuck in one position. When I turn the threshold CCW, the meter responds by slowly moving up. When I stop turning the threshold, the meter freezes in position.
I have a jumper next to the make-up pot on the daughter PCB. I'm using is a dbx 2151 for sidechain.
I haven't actually measured the output, I've listened to it and checked the meter. I'm planning to take the compressor to a friend who has equipment to scope. I only have a multimeter as it is for now.
Should I measure the sidechain vca for faults?
The compressor is passing signal thru fine, and the meter is stuck in one position. When I turn the threshold CCW, the meter responds by slowly moving up. When I stop turning the threshold, the meter freezes in position.
I have a jumper next to the make-up pot on the daughter PCB. I'm using is a dbx 2151 for sidechain.
I haven't actually measured the output, I've listened to it and checked the meter. I'm planning to take the compressor to a friend who has equipment to scope. I only have a multimeter as it is for now.
Should I measure the sidechain vca for faults?
there's a short jumper just above the cables on the control board also - common to forget..
Greg
Well-known member
I was referring to jumper that Gyraf stated. It's just above the 10-pin cables on the daughter PCB. Make sure that it's in place. Also, you definitely need to take a look at the output with a scope, with a sine and square wave if possible. If you plan to continue doing DIY projects, a scope is a must-have... X-mas is near, so it's time to treat yourself with an o-scope !!! :green:
Also, if you keep the jumper for makeup in your unit, your makeup gain will always be active, even when the unit is in bypass. If you want to disable the makeup gain in bypass, take a look at the PCB overlay that Jakob has provided, and it shows how to wire the bypass switch to disable makeup gain. I think this is very important.
But first let's get the unit compressing.
Also, if you keep the jumper for makeup in your unit, your makeup gain will always be active, even when the unit is in bypass. If you want to disable the makeup gain in bypass, take a look at the PCB overlay that Jakob has provided, and it shows how to wire the bypass switch to disable makeup gain. I think this is very important.
But first let's get the unit compressing.
After some troubleshooting I finally found my problem. There is a small
jumper leaving the positive power from the sidechain going into
the control cable + symbol. There was a bad solder joint here and
once correct blammo that thing fired up like a charm.
Compression seems to be fine all around, meter works well.
I feel pretty lucky after reading some of the messages on here
that mine got going pretty easy.
The main things I tried to do was:
(1) Measure ALL resistors before stuffing in the board
(2) Triple checking all components configuration
(3) Powering up WITHOUT any IC's in the sockets
And finally just tracing the problem to its source.
Ok I am off to play with my new toy! I want to try a 1176 next.
Todd
www.echoesrecording.com
jumper leaving the positive power from the sidechain going into
the control cable + symbol. There was a bad solder joint here and
once correct blammo that thing fired up like a charm.
Compression seems to be fine all around, meter works well.
I feel pretty lucky after reading some of the messages on here
that mine got going pretty easy.
The main things I tried to do was:
(1) Measure ALL resistors before stuffing in the board
(2) Triple checking all components configuration
(3) Powering up WITHOUT any IC's in the sockets
And finally just tracing the problem to its source.
Ok I am off to play with my new toy! I want to try a 1176 next.
Todd
www.echoesrecording.com
[quote author="gyraf"]there's a short jumper just above the cables on the control board also - common to forget..[/quote]
This jumper (next to the meter connections) is in place.
[quote author="Greg"]If you plan to continue doing DIY projects, a scope is a must-have... X-mas is near, so it's time to treat yourself with an o-scope !!! :green:[/quote]
Definitely! :razz:
[quote author="Greg"]Also, if you keep the jumper for makeup in your unit, your makeup gain will always be active, even when the unit is in bypass. If you want to disable the makeup gain in bypass, take a look at the PCB overlay that Jakob has provided, and it shows how to wire the bypass switch to disable makeup gain. I think this is very important.
[/quote]
I agree. I'm planning to have a switch on it later on.
/Flundran
This jumper (next to the meter connections) is in place.
[quote author="Greg"]If you plan to continue doing DIY projects, a scope is a must-have... X-mas is near, so it's time to treat yourself with an o-scope !!! :green:[/quote]
Definitely! :razz:
[quote author="Greg"]Also, if you keep the jumper for makeup in your unit, your makeup gain will always be active, even when the unit is in bypass. If you want to disable the makeup gain in bypass, take a look at the PCB overlay that Jakob has provided, and it shows how to wire the bypass switch to disable makeup gain. I think this is very important.
[/quote]
I agree. I'm planning to have a switch on it later on.
/Flundran
Hey guys,
came across another issue with my unit..
The unit is passing signal just fine. Make-up gain and threshold and meter are working fine as well.
The problem is on the ratio. It seems as if 2:1 is much higher than 10:1. It is almost like they are swapped, but not quite.
Besides, checking all the resistors values and checking for shorts and bad solder (all in the control section), what else would you guys recomend checking?? I'm kind of stuck on this.
I did all the testing on keith's Neutrik A2 and Steve's AP, so I know the testing gear is good.
thanks in advance
Gil
came across another issue with my unit..
The unit is passing signal just fine. Make-up gain and threshold and meter are working fine as well.
The problem is on the ratio. It seems as if 2:1 is much higher than 10:1. It is almost like they are swapped, but not quite.
Besides, checking all the resistors values and checking for shorts and bad solder (all in the control section), what else would you guys recomend checking?? I'm kind of stuck on this.
I did all the testing on keith's Neutrik A2 and Steve's AP, so I know the testing gear is good.
thanks in advance
Gil
Greg
Well-known member
BR:
What you describe is normal... Jakob can give a detailed answer in great detail, but here's the idea. The ratio do some type of averaging or attempts to maintain an average compression when switching between ratios. So, at the same threshold, the 2:1 will have a higher gain reduction than 10:1. If you want to check your ratios, there's a thread in the META. That is the way to check the ratios.
What you describe is normal... Jakob can give a detailed answer in great detail, but here's the idea. The ratio do some type of averaging or attempts to maintain an average compression when switching between ratios. So, at the same threshold, the 2:1 will have a higher gain reduction than 10:1. If you want to check your ratios, there's a thread in the META. That is the way to check the ratios.
Siegfried Meier
Well-known member
Hey guys,
This may have been mentioned here, but I can't seem to find the info I need.
I'm looking for a proper size 100nF Poly (MKT) for the GSSl - the ones I've used previously were always too big and made soldering them in kinda nasty and messy. Does anyone have a part no for Digikey or elsewhere for the ones I need?
Thanks so much!
Siegfried
This may have been mentioned here, but I can't seem to find the info I need.
I'm looking for a proper size 100nF Poly (MKT) for the GSSl - the ones I've used previously were always too big and made soldering them in kinda nasty and messy. Does anyone have a part no for Digikey or elsewhere for the ones I need?
Thanks so much!
Siegfried
Use 5mm-types, "2-modules", e.g. the Wima MKS05 100nf/63V
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