GSSL HELP THREAD!!!

[vertiges]

[quote author="craigmorris74"]Thanks for everyone's help on my build. The difference in volume of the channels was due to 10 ohm resistors being installed on the output instead of 100 ohm. Now my channels are less than 0.1 apart. The thing sounds great!

Thanks,
Craig[/quote]

:thumb:

Pics ? :wink:

eD

 

[craigmorris74]

Pics? Sorry, my builds are comically messy! They might set a bad example!

 

[vertiges]

:grin:

eD

 

[Barbera Media]

Well, I'm just about to finish up the design for my dual stereo GSSL unit, but I have a couple of questions that I can't seem to find the answers. If I possibly overlooked something, which is entirely possible, a link would be great.

Here's the few of questions I have:

I'm going to be building 2 stereo GSSL's into one 2U or 3U chassis, depending on what the final front panel design is. I was looking at power transformers, which are EXPENSIVE as you probably well know, and wasn't sure if using one transformer for both sets of boards would be a problem. Since they only consume around .9A each, would a transformer with 15V-0-15V secondary with around 1.8 to 2 amps be ok? Also would using a transformer with 18V-0-18V secondaries be problematic?

Also, I've searched for different places to purchase rack chassis, and found a couple of places, but if anyone would be kind enough to let me know their favorite place to purchase these, that would be great.

Are the required 30 100nf polyester caps, are there other typs of caps I could use? Could I substitute polypropylene caps instead?

I'd love to be able to silkscreen my own front panels. Is this process possible to DIY? I haven't found very much info as to how it could be done at home. Didn't know if anyone had any experience at this and would know if a home brew setup could work.

Finally, even though this compressor is a modern day unit, my design idea is to create a very vintage look for it. With that said, I've searched for different meters and knobs and have come down to a couple that I'd like to try to find. On the Sifam site, there are 3 different meters I'd like to purchase. The "vintage" series 202, 303A and 404A. The EMI "REDD 51" desk type meters. Does anyone know where I can purchase just 2 of these? Also for the knobs, I was thinking either the pultec types which i found a place to purchase them, but I was also thinking of the EMI TG type chicken head knobs would look great also, but have been unable to find them for small quantity purchase.

Once again thanks for any info that anyone might have. Hopefully there will be the birth of another GSSL very soon!

 

[signalflow]

Cases look here:

http://www.par-metal.com/

Chicken Head knobs, I get mine from here:

http://www.ampwares.com/

Click on the Knobs link on the left and it'll bring them up, their fender replacement knobs but they work fine. I have the blue ones on one of my GSSL's. Also, mouser has some black ones as well, pretty much the same thing.

As for the silk screen:

http://www.groupdiy.com/index.php?topic=28366&highlight=silk+screen

I think as long as your transformer has enough amps it should be ok to run 2 off of the same one 1.8-2 sounds good to me.

-Casey

 

[Barbera Media]

Casey, thanks so much for your help. Any ideas on the 18V secondaries on the xformer? Man, I really can't wait to get this thing racked up!

-joe

 

[keefaz]

[quote author="Barbera Media"]...I was looking at power transformers, which are EXPENSIVE as you probably well know, and wasn't sure if using one transformer for both sets of boards would be a problem. Since they only consume around .9A each, would a transformer with 15V-0-15V secondary with around 1.8 to 2 amps be ok? Also would using a transformer with 18V-0-18V secondaries be problematic?[/quote]
No, GSSL draws less current than that, more like 0.15A for each rail (with turbo boards),
see SSLtech post at:
http://www.groupdiy.com/index.php?topic=27275&postdays=0&postorder=asc&start=30

You may need heatsink for the 15V regulators if using 18V secondaries, although I used 18V on mine without heatsinks

 

[Barbera Media]

I think I'll just mount the regulators to the chassis bottom. I was planning on doing that anyways. I just wanted to make sure that everything in the circuit would run well with the extra voltage. I know how sensitive IC's can be sometimes.

Now what about the caps? I know orange drops are polyester, but do they fare well in this compressor?

 

[keefaz]

Only the 15V regulators ICs see the extra voltage they will be hot but should work flawlessly (especially if you mount them on chassis), the audio ICs should be powered with regulated 15V and 12V supply rail (which come from the regulators output)

Don't worry for the caps, as you build 2 GSSL, I suggest to build them with different set of caps, then you will hear if there is any difference
(Do not read too much web caps reports, else you will loose money :wink:, HIY Hear It Yourself)

 

[Barbera Media]

Keefaz,

You preach the truth my friend. I just assumed since there were so many, choosing different caps would change the sound dramatically, but it doesn't sound like the case. I might as well find the best price on the suggested price list that I got. Thanks for your help. I'm sure i'll be back before this is all over.

 

[keefaz]

I just wanted to point out that hearing what really change the sound is a more valuable personal experience than following advice for part selection
Take it with a grain of salt... You need some quality for electrolyt caps in the audio path, I used elna on mine, some used FC or FM panasonics ones, other used nichicon PW...

 

[Barbera Media]

Absolutely, especially since i've found myself often with the opinion of the minority when it comes to how things sound. Do you know of any place that sells vintage looking VU meters? I'd really like to find the Sifam REDD type VU's.

 

[Barbera Media]

Well, I put in my order to Mouser and a couple of other retailers for all the GSSL parts!! Can't wait to get started on this baby. Pics and sound clips will be posted upon completion.

 

[feza]

Hey,


I've ordered the GSSL-turbo board and the meter of this site http://www.diypartssupply.com/ and reading a lot about this compressor. But information is scattered around all this forum with the type GSSL what I want. For me it isn't very clear what to do building my version. I want the GSSL with the turbo-board and that Super Sidechain option. I've read about different completed versions of that kind (DaGoose for example) but what I have to do is scattered all over the place.

What do I need for PCB's to make the GSSL with the Turbo and sidechain option to work?

If I am correct I will be needing :

1 × GSSL PCB
1 × Turboboard
1 × Meter
1 × Super Sidechain
1 × Purusha GSSL Oxford switch case (cannot build them myself anyway)

That's it for stereo, right?

Other components like VCA's and such are still in copy and pasting in a digital document for reference, just studying. There are a lot of documents about the build and BOM list. I was hoping somebody can help me with this before ordering more components. :wink:


Thanks in advance people!

(BTW sorry for my cancellations with groupbuys, just a difficult situation here and glad that is over now)

 

[RedNoise]

Hi Feza!
IIRC I think SSLTech said you need two SuperSudeChain boards to run with a turbo board...
Best.

 

[MartyMart]

Yes, 2 x Supersidechain boards and a dual deck pot for switching them
together at the same time.

MM

 

[feza]

Thanks. I'll order tomorrow. :thumb:

 

[Chrome Heart]

OK Ive moved the subject here. Sorry Gyraf.
I have distortion on one side of the unit and no makeup gain control. Ive been over the board and I can not see any solder bridges. And im VERY nearsighted. All the jumpers are in the right spots. I tried to check the voltage at the IC's and I ended up frying one of the 10 ohm resistors.?? What happened there? At any rate, I replaced it and it seems to be OK.

The unit is compressing and the threshold seems to work as well. Im a bit stumped. I put a set of new 5532's in the output section and the problem still exists. One thing I did notice was that I had the 6.8 tant cap on the control board in backwards :roll: but corrected it and still have the same problem. Would having it reversed caused damage? Thanks for the help, and sorry for being long winded, but I wanted to get readers up to speed on this thread.

 

[RedNoise]

Hi Chrome , what happens when you completly disconnect the control panel???

 

[Chrome Heart]

You mean run it without the control board?