GSSL HELP THREAD!!!

[Arrigotti]

After finishing up my first GSSL and troubleshooting a few problems, I have it up and running ALMOST perfectly.

My only issue is the compression seems normal on the first 3 ATTACK settings (fastest 3), but when I get to the next three, the compression with stop at a certain point. (8db of reduction in the next position, 4 db of reduction in the next, and only a small amount 1db in the final position)

I check the resistor values on the control board for that switch and they test perfectly. I also check for continuity on the switch, and it was just fine. I checked to see if any of the resistors were shorted together by using the continuity function on my DMM, and I couldn't find a short there.

It baffles me a bit because the only this different is that I am switching a different resistor value into the circuit.

Any thoughts?.....

 

[gyraf]

Check the usual stuff (as mentioned many-times before) - but also re-check orientation of all diodes...

Jakob E.

 

[Arrigotti]

problem solved....the 3.3M resistor after the attack switch was a 3.3K instead.

.....swapped it out and all is well.

I guess I don't feel too bad since I didn't stuff the board. I can at least blame someone else, and take credit for fixing it.

Sometimes it seems like I just have to post my problem here and then I usually end up finding the problem.

Thanks!

 

[renx]

sorry to jump in like this...

What is the usual gain reduction of a signal passing through the gssl when is in bypass mode. I get 11 dB of GR. Is this "normal"?

My unit has both Aarhus and Oxford mode, and each board has only one vca populated. The GR is the same in both modes!

Regards.

 

[gyraf]

gain in bypass is either 0dB (when running unbalanced in/out) or +6dB (when running balanced)

Jakob E.

 

[renx]

thanks for your reply Jakob,
When I pulled out one 5532 and one 5534 from the slave board, gain came up by 6dB on this channel, which now leaves me with -5dB at bypass!!



I pulled out every IC, swapped them around and nothing. I just can't get above -5dB!!!

This is killing me...

 

[renx]

I solved the problem... I am writing this now just in case anybody would ever need it!

Problem: When building a gssl in Aarhus and in Oxford mode (2 pcbs), a gain reduction of -6 dB or -12 dB appeared in bypass mode.

Cause: The two boards grounds were connected at two or more points. Probably at pcb mounting screws.

p.s. all the ics were OK!

Regards,
Renx!

 

[Stagefright13]

Hi I hope this question isn't old hat but... I never used Lorin switches before. Can ya slap them in any wich way they fit on the control board? I see the center pins are keyed either 4 or 2 position and the board is labeled for wich switch. So does it matter? I have also got almost ALL my G-9 parts. And lotsa lorins there 2...

I did read EVERY meta for GSSL and G-9. Took me quite a while but was great reading. Picked up ALOT of info I can use for other projects too! My boards are all ready and powers up fine. Voltages look good just waiting on case. I may just string the xlr's out and try it tomorrow.

My only doubts are the lorins. Thanks for the help!

I can only afford to build 2 projects like every 7 months or longer so I am really happy about these 2, wish me luck. :green:

And TY Gyraf! These both look awesome!

 

[Harpo]

[quote author="Stagefright13"]... I never used Lorin switches before. Can ya slap them in any wich way they fit on the control board? I see the center pins are keyed either 4 or 2 position and the board is labeled for wich switch. So does it matter?[/quote]
Doesn't matter. 4x3 or 2x6 Lorlin rotaries are symetrical. Ohm it out to assure yourself. Turn the switch full ccw and set the end-stop washer to the max.desired step (i.e 3 for ratio, 5 for release, 6 for attack)

 

[Bluzzi]

I'm finally getting around to finishing this project.

The way the meters will be installed on my unit will make it hard to remove them at a later time.

I'd like to create a custom scale for it (rather than the milliamp scale that is on there now) and install it before I mount them (rather than do it later).

I'm undecided between a 10db or 20db scale.

Are any of you using more than 10db compression?

Also is the scale from 0 to 20db made up of linear steps?

jim

 

[Siegfried Meier]

hey guys,

Just finished a GSSL (my fifth) and this is the first one with a ratio problem. 2:1 and 10:1 are fine, but switching to 4:1 makes the meter jump anywhere from 1 dB to 4 dB of gain reduction, depending on the attack and release settings (fast attack makes the meter go higher, slower makes it lower). This is with no audio coming through at all. Otherwise, it sounds and performs great. This is the first I've done with Greg's sidechain board. Any idea what's causing this?

Thanks,
Sig

 

[Siegfried Meier]

It's so weird, something is shorting out around the 1M2 and 1M8 resistors on the top left hand corner of the control PCB. If I bend the PCB back and forth lightly it'll come back, but I think I've made it go away. Can't figure out what's shorting at all. Perhaps something inside the ratio lorlin switch is internally shorting??

Sig

 

[flintan]

How much space is there for the 100n caps on the PCB? Looks like ~2,5 mm (width) to me but i don't have the board..

I know standard 100n Wima polyester are that size but I'd like to have polyprops there but i can't find any that small.

 

[flintan]

[quote author="flintan"]How much space is there for the 100n caps on the PCB? Looks like ~2,5 mm (width) to me but i don't have the board..

I know standard 100n Wima polyester are that size but I'd like to have polyprops there but i can't find any that small.[/quote]
Got that confirmed from another source..so i answer my own question. :green:

Yes, it is ~2,5 mm on most of the places.

 

[Bluzzi]

Is it me or are the MillMax SIP sockets for the THAT VCAs a little loose? I mean the VCAs don't fit snuggly in them.

I got Mouser p/n 575-113108 which is MillMax # 310-13-108-41-001000.

Its not loose enough to fall out but not tight enough for me to feel comfortable ( is this a Freudian slip?).

jim

 

[Nadege]

hello,

I've build a Gssl with success.. At least it was working great for a week. Than something wasn't good anymore.

I opened it, measure everything and found that the +15v rail was less than 1 volt.

I scratch my head changed some component (the +15v reg, the diode bridge and some resistors )
put everything back together
everything was now fine again without the IC in place

I put the IC Back on the pcb, everything was fine

I checked the voltage for the last time and now I lost the +15v again...

Something makes my reg blowing. But I can't figure out what's going on...

It seems that it's blowing when I Switch the unit on.

Any idea?

thanks a lot

 

[gyraf]

A bad batch of 7815's?

I don't remember ever having a 7815 fail in the GSSL - not even when 15V rails shorted.

Jakob E.

 

[Nadege]

Should something else than the 7815 be responsible for the lost of the -15v rail ????

 

[dustbro]

[quote author="Nadege"]Should something else than the 7815 be responsible for the lost of the -15v rail ????[/quote]
Could be.
pull the jumpers for +15V/-15V right in the center of the board and measure the regulators again. that will narrow down if it's your 7815 or something further in the circuit.

 

[dspruill]

Hello everyone, I am in the testing phase of my GSSL build. It seems to work except when I put in the 47k resistor going to the threshold pot the unit no longer will compress. If I just connect with a wire from the board it will compress. I have the +12v and the -12v going from the control board to the pot, until I put in the resistor, then my +voltage on the pot is only about +1volt. I assume this is the voltage drop because of the resistor but it disables the compression.

Thanks in advance
David