GSSL HELP THREAD!!!

[Bluzzi]

vertiges - I 'm not sure any of that causes anything, I just think "overkill" can't do harm and may do some good.

Maybe the caps should be spaced but the transistors? Isn't the signal there being amplified up a notch? Again I'm just saying these things in a precautionary way. Not sure it would make a dif.

I'll find out tonight when I plug mine in. I got my XFR to put out the correct voltages finally (found another wiring diagram). So now I get 17.5vac relative to CT on each side. I'm still getting high volts between AC Ground and CT but I'm taking the chance its normal.

I'll get back here and report "smoke" or "no smoke" !

jim

 

[vertiges]

Jim,

Finally you're gonna switch your GSSL on !!! Great ! Maybe wait before putting the ICs ! Check the voltages everywhere before ! :wink:

I wish you no smoke and no explosion ! Do not put Montreal in a black out a few days before Christmas !!! :green:

...and no hum of course !!!

eD

 

[vertiges]

Jim,

And about your high voltages, remember that the ov of your XFR and the ground of the AC are linked by the PCB. If you make the test of linking these two point you'll get the normal voltages.

eD

 

[Bluzzi]

I'm going to follow wiring as follows.

My CT and 2 voltages will go to 3 pin power in connector on PCB.

AC Ground will go to chassis. From there I will connect to pin 1 of XLRs which are Ground on PCB.

I almost forgot about ICs! Thanks for reminding me! I'll take them all off. I guess that includes 5534 and TL072 right? Of course VCAs as well.

I think I have a voltage chart somewhere.

jim

 

[vertiges]

Jim,

That's the correct wiring.

About the ICs, yes all of them, 5532, 5534, tl072, tl074 and mostly the VCAs ($$$) !

About the voltages charts : you should have something like this :
(It's a cut & paste from an old post)

5534 Left input
Pin4 -14.97V
Pin7 14.78V

5534 Right input
Pin4 -14.97V
Pin7 14.77V

5532 Left out
Pin4 -14.97V
Pin8 14.77V

5532 Right out
Pin4 -14.97V
Pin8 14.77V

TL072
Pin4 -12.07V
Pin8 12.21V

TL074
Pin4 12.22V
Pin11 -12.07V

But if you already have the +/- 15 volts and the +/- 12volts correct on the rails you're in business !

eD)))

 

[guavatone]

I too have a hum when my monitors are cranked. I'll check my 12V lines. I wonder if using a direct solder to ground makes a difference, since now mine is using molex.


-Bluzzi you should definitely have more than 15VAC feeding the gssl, I don't think 17.5 is too high at all.

 

[Bluzzi]

thanks for the voltage list vertiges.

guavatone - no I didn't mean the 17.5 to be high, just the voltage between AC Ground and CT of the secondary on the PT. Since I'm not the only one getting that I'm guessing its normal and probably very low current.

I'm trying to find the time tonight to be able to concentrate on connecting the AC to the pcb. Waiting for things to quiet down around my house. I'm debugging a GR MP-2 also. I just finished a JLM Powerstation and burned it in for 15 minutes (without a load) and seems OK.

I get very nervous when I first turn a new piece on for the first time.

Where there's no smoke, there's hope.

jim :green:

 

[3nity]

Jim...there's nothing to worry if you followed everything as it is...as long as your PSU works fines.

 

[Bluzzi]

Just finished measuring. I disconnected the Sidechain board to elliminate extra variable in case of problem.

All my 5534 were -15.09 and +14.71.
The TL072 and TL074 were both -12.09 and +12.20.

So far so good! No smoke lots of hope.:thumb:

At this stage I guess I can insert the chips back including VCAs right?

(vertiges your voltage list was what got me going. Thanks again for helping out.)

jim

 

[vertiges]

Jim,

That's look good !

Yes, you can put the chips back.

Double check the orientations :

a) the 5534 between the inputs and the VCAs. The positions are "reversed"
(I'm not sure it's the good word in English... reversed ? inverted ?)
b) the THAT between the channels and the Sidechain. (I blew up one because I inserted it in the wrong way :sad

Maybe do not push them totally in the sockets in case of you would take it off for troubleshooting. (I wish you not !!! :wink: )

eD)

 

[Nadege]

hello

thanks for all those helpfull info :grin: . I'll try to move the W04 and if it's not working, I'll try the external PSU.

Bluzzi, as vertige said, I have repair a broken trace on the control PCB, That's why there isn this strange wire there. And on my first unit I put a spst switch witch doesn't bypass the makeup gain, on the other, I put a standart DPDT switch with makeup bypass, and it's way better like this, it's a bit unuseable without the makeup bypass (see gyraf's schematics)

I'll keep you informed whit my progress

thanks a lot

 

[Bluzzi]

I'm usually careful with orientation but I'll make sure I pay attention. Yes the VCA are tricky because the sockets hide the silkscreen showing orientation on the pcb.

I'm doing housework between all this so I'll be putting in chips back probably this evening. At this point I'm confident electrically everything is OK. I'll wait to confirm audio is passing well until I wire in the Sidechain pcb again.

jim

 

[vertiges]

Bluzzi,

Here is a link to a pic of the PCB in case of you would have a doubt :

http://www.vertigesproductions.com/diy/GSSLmainPCB.jpg

eD)))

 

[Bluzzi]

thanks vertiges, already done but I appreciate your help.

I'm using an LF353N for the TL072 and LF347 for the TL074. I forget why I ordered these but I look at specs and they look like substitute except that LFs use more current so I hope that will not present a problem.

Anyone know if those would cause any problems?

Thanks again.

...tonights the night.....

jim

 

[Bluzzi]

I couldn't resist and turned it on with ICs in. I'm such a chicken...

Still not smoke or loud detonations of any kind! :grin:


I touched all parts for overheating after 1 minute warmup and the regulators (7815 and 7915) are hot but not that I can't leave my finger on it for a few seconds.

The 2 78L12 and 79L12 transistors however are burning hot! Is that normal?

jim

 

[vertiges]

[quote author="Bluzzi"]I couldn't resist and turned it on with ICs in. I'm such a chicken... [/quote]

:grin: :grin: :grin:

I don't know about the transistors... I don't remember how hot they were...
Unfortunatelay, I don't have the time to unscrew my rack right know.

And so ? Have you plugged it ??? Does it work ?????? :razz:


eD

 

[Bluzzi]

My studio is a total mess! All kinds of parts, wires, tools all over the floor even on top of my mixer! So no I haven't tried it yet 'cause I have to clean up first and frankly I'm pooped! I've been cleaning house the last 2 days!

So instead I'm going to test out my second GSSL board the same way. I need to feel some sort of accomplishment. Also if I have a problem on one board its good to have another to compare to.

Maybe I'll get to put audio through it tomorrow but only have a few minutes in the morning. Otherwise I'll be doing it on Tuesday.

I want to see that meter moving!

jim

 

[vertiges]

Suspens... :wink:

eD

 

[warpboy]

Hello,

I'm actually reading all the posts for this topic (158 Pages :? ) because I've a problem with my gssl.
for infos the vca are THAT 2180LA.
The problem : One channel is distorted.The signal is correct at the output of the input NE5534.The problem seems to be in left vca (NE5534+2180LA), but at this time, I've really no idea :?
I have permuted the ne5534 and That 2180 from left to the right channel and it's ok..
The other channel works correctly (Threshold, attack,realease and make up work well)....
Any idea?
Thank you by advance :wink:

 

[scottCFP]

Hi all!

Thanks Jakob for this project. Incredible.

First 'pro DIY' build. Nearly there.

I've scrapbooked this thread, and have found some voltage charts, and to the best of my knowledge I am good (15 and 12), opamps. Haven't found VCA voltage chart. Has anyone compiled a voltage chart from all of the info in this thread? VCAs?

I'm having trouble passing audio. I believe that I am shorting out somewhere as I have continuity between I/O hot and neg, but am nearly 100% sure it is not a solder problem. (I've checked for bridges with a backlight on the component side, and light goes through where it should)

Has anyone had any similar symptoms and might be able to offer a bit of knowledge?

Thanks

Scott