GSSL HELP THREAD!!!

[thomasdf]

Hi everyone

Just beta tested my GSSL, and my right channel passes audio but it is not compressed at all and not affected by the output gain pot.
The left channel works perfectly...
I am bypassing the unit with a relay bypass board on which I switched relays between left and right and the problems remains on the right side...
When I plug the right side only, the output is uncompressed and the sidechain seems untriggered (the meter doesn't move a bit).

Everything points to a bypass problem on the INPUT of the unit but if I swapped the relays and the problems remains on the right side well... Anybody experienced that?

I'm back to my debugging!

Edit : after further search, it looks like I have a problem with my bypass... Weird... I'll keep looking!

 

[Ave Crux]

The IC sockets that were stuck together in a straight line threw me off a bit since I wasn't sure if you had to "snap" it off.. Messed up in the last IC socket and I missed one socket.. It had extras so I tried to snip off just one socket, might have been a better idea to snip both half and half?
Anyway, it's angled a very very tiny amount. Tried to put the chip in and it went in fine although the last peg is a bit bent.. Checked for continuity though and it seems fine.
Should I still redo that..?

EDIT: yeah  I am most likely going to redo that.

 

[Gustav]

The IC sockets that were stuck together in a straight line threw me off a bit since I wasn't sure if you had to "snap" it off.. Messed up in the last IC socket and I missed one socket.. It had extras so I tried to snip off just one socket, might have been a better idea to snip both half and half?
Anyway, it's angled a very very tiny amount. Tried to put the chip in and it went in fine although the last peg is a bit bent.. Checked for continuity though and it seems fine.
Should I still redo that..?

EDIT: yeah  I am most likely going to redo that.

It doesnt really matter. You could put in 8 singles if you wanted to, since they are not linked in any way.

As long as you feel the structure is good.

Gustav

 

[Ave Crux]

Thank you Gustav,

Sorry for flooding with basic questions, I can't seem to find the answer anywhere.. But I need a socket for the power transformer I got (2x15v) and can I just get that from Mouser? I looked at the IEC sockets there and I'm not quite sure which specific one I need..

EDIT: found this on mouser http://ca.mouser.com/ProductDetail/Schurter/62202100/?qs=sGAEpiMZZMtz8P%2feuiupSXCZijoDTJT7CpNaaNTPFbk%3d and I think I should be okay right? Does the rating of 250 VAC mean that it handles UP to 250 VAC? I live in Canada and our residential voltage is 120v..

EDIT AGAIN:
Found the answer! So I can use an IEC socket with a 250VAC rating safely so long as the actual voltage does not exceed that. So 120 should be okay. (Please correct me if this is incorrect)

 

[thomasdf]

Hi folks
Further testing on my unit showed that the right channel is not working.
When I only plug that channel the meter doesn't move so I think my problem sits between the input of the board and the sidechain input, right after the 22uF 35V cap.
My +15 / -15 is correct, as well as my +12/-12 and I tried swapping the NE5534's ... similar results
I'll keep on searching and will keep you posted

Edit: I tracked down a 1Khz signal and the Right channel's input NE5534's output (tricky haha) is very distorted... like a fuzz pedal with a low signal. I checked the 22pF capacitor that's here for unity gain and it is ok. The 22uF 35V electrolytic is fine too. The opamp itself is fine too, swapping it didnt change a thing.
I noticed that my regulators are getting too hot to touch pretty fast especially the two taking care of the +15/-15 but maybe it's ok... The right channel NE5534 get hot really fast too, way way hotter that any other 5534 in the comp...

 

[thomasdf]

Hi still me I'll keep on writing my novel!
When I remove the 22uF cap that's right before the sidechain input and main channel VCA (I therefore cut the signal path) the sound is clean at the output of my NE5534... So I guess I have some sort of impedance mismatch there with what's going on after that cap. Still need to figure it out. Any clue is welcome!

 

[unklepablo]

Hey everyone,

I just wanted to share that I finally got my gssl working. It was a great lesson in electronics as only my 2nd build (the 1st being an Atari punk console). The most important part for me was the quality of the solder joints. I spent 2 weeks looking for problems and it was fixed by removing bad solder joints and doing them again.

Thanks for the advice about the vu meter, i forget who it was now as its late, i fixed it by taking it apart and soldering back on a wire that had come off inside and gotten stuck to the plastic.

Now I need to fix the noise problems, I get -46db hum in left channel and -36db hiss in the right. It compresses perfect with the vu meter displaying as it should. Everything is working fine, aside from the noise.

I will head back to the search button tomorrow.

It has a nice big wide console sound, I love it!

 

[Ave Crux]

Hey everyone,

I just wanted to share that I finally got my gssl working. It was a great lesson in electronics as only my 2nd build (the 1st being an Atari punk console). The most important part for me was the quality of the solder joints. I spent 2 weeks looking for problems and it was fixed by removing bad solder joints and doing them again.

Thanks for the advice about the vu meter, i forget who it was now as its late, i fixed it by taking it apart and soldering back on a wire that had come off inside and gotten stuck to the plastic.

Now I need to fix the noise problems, I get -46db hum in left channel and -36db hiss in the right. It compresses perfect with the vu meter displaying as it should. Everything is working fine, aside from the noise.

I will head back to the search button tomorrow.

It has a nice big wide console sound, I love it!

Glad you got it working! I was reading some METAs and you can try loosening the bolt on your toroid and rotate it until it minimizes the hum.

 

[olebrom]

[/quote]

Send me a mail, Ill sort you out.

Gustav
[/quote]


Thanks!!! email sent. Eirik

 

[unklepablo]

Hey everyone,

I just wanted to share that I finally got my gssl working. It was a great lesson in electronics as only my 2nd build (the 1st being an Atari punk console). The most important part for me was the quality of the solder joints. I spent 2 weeks looking for problems and it was fixed by removing bad solder joints and doing them again.

Thanks for the advice about the vu meter, i forget who it was now as its late, i fixed it by taking it apart and soldering back on a wire that had come off inside and gotten stuck to the plastic.

Now I need to fix the noise problems, I get -46db hum in left channel and -36db hiss in the right. It compresses perfect with the vu meter displaying as it should. Everything is working fine, aside from the noise.

I will head back to the search button tomorrow.

It has a nice big wide console sound, I love it!

Glad you got it working! I was reading some METAs and you can try loosening the bolt on your toroid and rotate it until it minimizes the hum.

Thanks for that I will mess with the position of the toroid, I tested without it earlier and it was the same. Ive noticed that if I take out both NE5532P chips the hum and hiss goes away so I will order some replacements and hope it works. It took a lot of testing to get mine to work and I could have shorted them out at some point.

 

[thomasdf]

Just an update, my unit is now fully working too. One of the 47K summing resistors in the sidechain was going voodoo on the whole right channel...
Anyway, now it's fully working as does the bypass PCB. Testing showed this comp to be quite kool even though the "grab" is a bit different from the 4K desk comp that I am used to. I find the GSSL to be "snappier" with similar settings... The Sidechain filter is a GREAT feature... Really helps keeping the mix glued yet a bit alive.
I now need to figure out the lighting and do the lazertran on the faceplate... Will post pics when I'm done!

 

[sonicwarrior]

Can anyone please confirm that the Lorlin rotary switches with the Mouser numbers 10WA135 and 10WA137 really feature a D shaft axis?

I currently have Lorlin switches with round shafts installed but don't like them because the set screw knobs are tearing the plastic axis down.

Or are there any other fitting (in the control PCB) alternatives preferably with metal shafts?

 

[thomasdf]

I can't help you on that, but have you tried cutting the shaft in a D shape?

 

[gyraf]

Usually, set screws does not tear plastic shafts - I use them constantly, and NEVER have problems. You must have some other problem going on here. But I can't figure out what exactly...

Jakob E.

 

[kante1603]

Usually, set screws does not tear plastic shafts - I use them constantly, and NEVER have problems. You must have some other problem going on here. But I can't figure out what exactly...

Jakob E.

Maybe a 1/4" pot cap on a 6mm shaft can cause this?The shaft can at least move around 0,35mm then.Give the set screw some (brutal) force,and if it has a spiky tip then.......


Best,


Udo.

 

[ptron]

aaah well.... i came back from tour finally ! was a long one.
got back in the bench and with help of an osciloscope i found EC on left vca was different than right vca.... i changed the 5532 to get same reading.... then output volume was 6 db quieter on left channel, not 2.5 db.... in the end it was a nut making a short between cold and ground on the bypass board hehehe
thanks harpo for your suggestions and all the help
all the best!

 

[Ave Crux]

Okay here we go guys!

Powered up my unit for the first time last night! I was so paranoid of turning it on I had to find some pliers with rubber grips on them to switch on the power switch, heh. But anyways, hooked it up, powered it on, lights in my room "blinked" for a split second, then nothing happened. Opened up the fuse socket, and whaddya know, it blew!

My toggle switch rating is a 3A 125VAC, fuse is a 315mA slow blow. I've been trying to find solutions in this thread, but perhaps I might have just miswired something?

The toroid I am using is the one in Gustav's store, I believe it's the VPT3-830?

So, I have attached some photos here if anybody may be kind enough and have time to look and see if I messed up some wirings.
Thank you guys!

Here is the link to the folder of images, the one posted in this post are pretty huge.
https://www.dropbox.com/sh/ropukw37xlqqsrj/AAAFCv28KiAR9gq39kJXB8m3a?dl=0

Also, I should also note that I didn't have any of the chips inserted when I powered it up, just the sockets.
The images here have the chips in them because it was when I didn't know I blew a fuse, and just thought I gotta try it with the chips in this time...

 

[Gustav]

First off, I would remove the pictures. They are not helping at all in that size, and they are clogging up the thread a bit.

Next up, wiring looks fine (assuming you are in 110V mains land), but if you want to check, you  can de-attach the 4 pin connector from you set up and measure if you have 15VAC from each side to the middle, and 30VAC from side to side. (multimeter set to measure alternating current at this point, since we dont rectify it until we hit the diode bridge on the PCB).

15 - 0 - 15 = 15 from each side to middle, or 30VAC in total across.

I would rather see a shot of the bottom of your PCB. I think the soldering work on the switches looks a little off, so I suspect the real problem may turn out to be a short somewhere in your supply.

Gustav

 

[Ave Crux]

First off, I would remove the pictures. They are not helping at all in that size, and they are clogging up the thread a bit.

Next up, wiring looks fine (assuming you are in 110V mains land), but if you want to check, you  can de-attach the 4 pin connector from you set up and measure if you have 15VAC from each side to the middle, and 30VAC from side to side. (multimeter set to measure alternating current at this point, since we dont rectify it until we hit the diode bridge on the PCB).

15 - 0 - 15 = 15 from each side to middle, or 30VAC in total across.

I would rather see a shot of the bottom of your PCB. I think the soldering work on the switches looks a little off, so I suspect the real problem may turn out to be a short somewhere in your supply.

Gustav

Thanks! And sorry bout that, I'll take 'em out but I'll leave the link for the folder. I'll post a shot of the bottom of the PCB when I get home.

Would that mean that I should disconnect the connector from the main PCB board, then measure the secondaries to see if I'm getting the proper VAC? That would mean I will turn them on again, right? And also put a new fuse?

 

[Ave Crux]

Okay so I have posted more photos in the folder with images of the back of the pcb.

I put a new fuse again and checked the secondaries. Right off the bat before I turned on the unit, the black wire and the two wires in the middle that soldered together had 2VAC. the yellow wire had 1.6VAC.

Then I turned it on, all the secondaries dropped to 0V. turned it off, they come back again to 2VAC and 1.6VAC respectively. Also checked the fuse, blew up again.

Any help would be great! Thanks.

https://www.dropbox.com/sh/ropukw37xlqqsrj/AAAFCv28KiAR9gq39kJXB8m3a