GSSL HELP THREAD!!!

[ncoak]

excellent, thanks for clearing that up.

 

[ilfungo]

ciao
Can you tell me which switch I use to monitor simultaneously two super side-chain board?
thanks

??? ??? ???

 

[rooster21]

I need information on which components need to be removed if I'm using an off board PSU (mnat's), I also assume that jumpers need to be installed at certain places?

Can someone point me in the right direction? I tried searching this thread and didn't come up with much.

Thanks
GdS

 

[ilfungo]

Ciao
no for Mnats but
I hope this can explain:


http://www.youtube.com/watch?v=Lv_wmlAWnkA

 

[rooster21]

Ciao
no for Mnats but
I hope this can explain:


http://www.youtube.com/watch?v=Lv_wmlAWnkA

That's not exactly the same, the CRC board is just for filtering, you are still using the on board power supply section to get regulated +/-15v. Mnats PSU outputs the +/-15v required for the GSSL therefore allowing you to bypass the power supply section (as far as I can undersatnd). Thanks though, I know what to do if I have a noisy GSSL!

Any other takers?

 

[Alessio]

It works HARPO!
I've added 10dB of gain to my unit!!!!!! It sounds amazing!!!!

Thank you soooo much!


Alessio

 

[mac]

this is a link for Rooster21... Lukas Colour Roadmap

follow the pink and blue power rails!!!

http://www.groupdiy.com/index.php?topic=37246.0

 

[mitsos]

I used an offboard PSU for the +/-15V.

Leave off the transformer, both bridge rectifers, the 2 large electrolytic caps, the LM7815 and 7915, and the two smaller caps next to them.

I brought power to a molex connector in the top left corner in the "color roadmap". In the picture it would be "positive,Ground,negative" top to bottom.  Then two jumpers in the bridge rectifier next to the molex (connect the pads horizontally, so that the power goes to the purple and blue lines) and then two more jumpers between the pads for the "in" and "out" pins of the 7815 and 7915 regulators (connecting blue to blue and purple to purple in the roadmap). You could also just take the power with wires to the regulator output pads and skip the molex and jumpers, depends on how "clean" you want yours to look. 

 

[rooster21]

Thanks guys, exactly what I was looking for, the link in Mac's post should definitely be in the meta for this project!

Back to building with confidence. Happy DIY'ing.

 

[mac]

Hello all,
rainy and gloomy outside - warm smell of solder here inside!!  ;D

I dont know if this has already been done in the past (this thread is awful long now), but I am testing two main boards today before I pop in the opamps and VCA's. So I finally got around to doing this little picture.

Thought it may be of some help to others too!

 

[mac]

 

[beatnik]

Hi everybody!

I need some help with my GSSL built from gyraf project. The clone isn't passing audio but the power section seems to be fine as the led lights up and the voltages from regulators seem to be ok.

Here are my voltage readings on the opamps, with no input signal. Please help me finding where some errors could be.

L&R inputs NE5534

pin1 -- 11,97
pin2 -- 0
pin3 -- 0
pin4 -- -15,09
pin5 -- -0,63
pin6 -- 0
pin7 -- 14,46
pin8 -- 11,96

L&R outputs NE5532

pin1 -- 13,76
pin2 -- -0,05
pin3 -- 0
pin4 -- -15,10
pin5 -- 8,10
pin6 -- 9,34
pin7 -- -13,86
pin8 -- 14,45

NE5534 on VCAs

pin1 -- 11,62
pin2 -- 0
pin3 -- 0
pin4 -- -15,12
pin5 -- -0,89
pin6 -- 0
pin7 -- 14,45
pin8 -- 11,65

TL072 & TL074 (some pins change voltage depending to the threshold pot)

pin1 -- -0,09 to 3,13
pin2 -- 0
pin3 -- 0
pin4 -- -12,18
pin5 -- 0
pin6 -- 0
pin7 -- 0
pin8 -- 11,89

pin1 -- -0,14 to 0,20
pin2 -- 0
pin3 -- 0
pin4 -- 11,89
pin5 -- 0
pin6 -- 0
pin7 -- -0,03 to 0
pin8 -- 0
pin9 -- 0
pin10 -- 0
pin11 -- -12,18
pin12 -- 0
pin13 -- 0
pin14 -- 0,22

i have made some more measurements.

I have a problem on the +12V rail for sure, because i have +22V on 78L12 input, but on the output of the regulator i have a voltage that oscillates from about -0,5 and +3V.

Could be a damaged regulator or something else?

 

[ilikeit]

hi all
i have a little problem with my GSSL
+/-15v are ok
+12v ok
but -12v=0
when i plug the tl074 or tl 72 -12v=0V
if i remove the both  i have -9v at the 3.9k
if i cut the pcb at the end of my regulator i have exactly -12v
i have change my 79l12 but same results.........
anybody can help me???

thx

 

[Alessio]

When I change the 2 15K resistors for 2 27k for the unity gain, I'm changing the INPUTS of the VCA? Not the output. That's right?
Just to have it clear...

Thank you,

Alessio

 

[Harpo]

When I change the 2 15K resistors for 2 27k for the unity gain, I'm changing the INPUTS of the VCA? Not the output. That's right?
Just to have it clear...

With input resistor 27k in front of the audio-VCA you substitute the 15k feedback resistor at the following opamp stage by 2x 27k in parallel, giving non-standard-value 13k5. This will give you unity gain for balanced out operation.
For unbalanced out unity gain you substitute these 15k feedback resistors by 27k resistors.
You can make it switchable for balanced/unbalanced operation by switching one side of one of these paralleled 27k feedback resistors open circuit, so only 1x 27k resistor stays in circuit. Use a double pole switch for both L+R channel.

 

[ncoak]

Search back through the thread for 22uf and 100uf.... there is some chatter about using higher quality electros in certain places.

(easy way i have found to do this is to use the "print" feature and then cut and paste into a word doc - so you can search for individual terms through a long thread like this one)...

good luck,
Mac

ah....you're a lifesaver! thanks for the tip.

 

[mac]

 

[meekie0]

I have a low frequency distortion on the one side of my gssl
I’ve tried changing all the chips and looked at all the soldering joints
It even distorts when the compressor is switched in the out.
I know it must be a component but witch one.
Any help would be great

 

[stereokillah]

which channel left or right, do you use tiroidal psu tx or square tx on your board?

 

[meekie0]

hi. i use a toriod psu
also ithink its the right hand side
but not shure, not at home right now

cheers thomas