GSSL HELP THREAD!!!

[Siegfried Meier]

Thanks for the reply. 1 question. What exactly do you mean by "2-modules"? Do you have a Digikey part no.? I can't seem to find these.

Thanks!
Siegfried

 

[Greg]

I don't think Digikey carries WIMAs. I used some WIMAs on one of my GSSLs, but they were big and some of them had to be glued to PCB and fed with wires. It was a more tedious job, but of the two I have, the one with the WIMAs is my favorite. I also used Nichicon PW caps and DBX 202 for VCAs.

 

[gyraf]

What exactly do you mean by "2-modules"

"Modules" are size-measure for electronic stuff - 1module = 1/10inch = 2,54mm = the distance between two pins in a DIL-pakage IC.

Jakob E.

 

[Siegfried Meier]

Gotcha! Thanks!

Siegfried

 

[Siegfried Meier]

Does anyone know the exact font that SSL uses on their front panels?

Thanks!
Siegfried

 

[Flundran]

Hello all!
I would like to know the normally used input level in volts.

How do I use the trimmers with dbx202 vca's?

I also have a problem with 50Hz noise on outputs when I open the dbx202xt output with make-up pot. (Inputs are shorted while measuring.)

/Flundran

 

[ability]

Well i got my hole pcb wired up everything is on it checked all but the only thing i have to do is connect the trafo. Just to be sure i ask this ,

I have 2 outputs with 18 v and 2 with 0 v, now do i connect the two 0v together and put them on the middlle of the three points used for the external power and then the two 18 v on each side?

Do i need to connect the ground of the outlet to that 0v connection point to?

I will start offcourse with emty ic sockets!!!

THANKS

( used a 2 * 18v 15va ) :?

 

[BR]

Hey ability,
yes to question 1. But I'm not quite sure if the 18V will give you problems with the regulators. All mine were running fine with a 15V traffo running right under that.


Connect the primary to Hot and neutral on the outlet and ground xlrs to chassi ground on the connector.

Hope it helps.
and if it doesn't, its your fault for trusting me... :green:

 

[BR]

OK...
I just did the Ratio measurents on my comp using Keith's step by step directions and got very wackie results.
I made sure I had 20dBs of reduction to get away from the knee and this is what I got:
@ 2:1 - In= +20dB Out= +9.2dB , gives me a 2.17:1 (good enough)
@ 4:1 - In= +20dB Out= +7.7dB , gives me a 2.6:1 (crasy)
@ 10:1 -In= +20dB Out= +6.8dB , gives me a 2.95:1 (huh??)

The test was done on a Audio Precision and I'm pretty sure I did it right.
I do have a trimmer in place of the 1K resistors going to the VCA which I trimmed to get the best result on the 2:1 ratio as you can see above. I was expecting to get at least close to the other ratios, but these are crasy.

Where should I start looking. I'm running out of ideas.
Any help is extremelly appriciated. I was trying to finish this one by the end of the year, but it's not looking very good.

thanks again
Gil

 

[gyraf]

Gil,

When you change ratio, you change the threshold as well. So it's not easy to measure ratios by simply flipping the ratio switch.

Jakob E.

 

[BR]

Hey Jackob,
When I was doing the test I didn't just switch the ratio. I brought the AP level back down (to 0dBu) and brought the threshold all the way up to 0 reduction and then switched the ratio and brought the threshold down until I was getting 20dBs of reduction again, and then I bumped the AP +20dbu and wrote down the readings that you see above.
I other words, I made sure that I ran the test like if I was testing 3 different units at the different ratios.
I'm going to recheck all my resistor values, specially around the ratio rotary and the side chain VCA and see if there is anything funky..

In the mean while, anything else I should be worried about?? bad VCA?? Just guessing at this point.

Thanks
Gil

 

[Greg]

I would run the test again to make sure. This might not be the problem, but it seems to me that increasing the input by 20dB is a bit much. Try it next time with an increase of 10dB and post your results. I actually used the VU meter on my console for the basic test. Then I went back and took actually voltage measurements to tweak it for more precision. Just to make sure, are you using 20*log10(V2/V1) to get the dB value? If you want, you can just post voltage readings.

If you get the same results, I'd check resistor values around the ratio control.

 

[BR]

Hey Greg
thanks, I'll try that in the next few days, I'll post the results then..
In the mean while, I'll check the resistors.

Gil

 

[BR]

Just checked all resistor color bands and they all match right to the pcb silks. So, I really don't know what I did wrong.
I was going to try switching the orientation of the rotary, but I don't think that should matter, since its just changing posts.

One thing is that I'm using the DBX 2001 cans and I didn't populate the 1M resistor and the distortion trim, but I don't think that should matter at all. Since its just for distortion. Should I short it??

Thanks
Gil

 

[Greg]

No don't short it. I'd suggest putting the 1M and distortion trim in the circuit.

 

[FMS56]

This is a little off the subject, but...
I just ordered a Behringer BE46 meter for the GSSL project. Does anyone have any size information on these things? I'm designing a panel with Front Panel Express, and need to know the size and shape of the mounting hole. And whats up with Sifam these days? I was trying to place an order with them, but got no response. Maybe they're off till the new year...

Cheers! :grin:

 

[mcfate]

Hey all,

This has probably been covered elsewhere in the thread, but I couldn't find the exact info.

I'm a basically non-techie recordist who built an ssl clone monkey-follows-recipe style, and I've used it for about a year and its great. I recently got ahold of some 202C vcas, and I'd like to swap the existing 2180s. Can I simply remove the 2180 and 5534 and physically install the 202C over the existing components? Or do I need to unstuff all the existing 2150-related components first? Also, what about the distortion trimmer - do I leave it or remove it or what? Thanks a lot!

Gideon

 

[gyraf]

Complete Unstuffing is needed..

Why not simply build a new one?

Jakob E.

 

[mcfate]

And what about the distortion pot thingy?

Building another one is definitely on the agenda.

 

[gyraf]

And what about the distortion pot thingy?

What about it?

If you're asking if it should be removed, then no.

It's not in the under-the-202-area, and you'll need to trim distortion with the 202 as well.

Jakob E.