GSSL HELP THREAD!!!

[Aaron Wiles]

Thanks Greg. Any suggestions where I might start? Or possibly the most likey spots where it may be shorted?

Thanks again. :wink:

 

[Fredrik]

Hi all,


A simple question regarding the 50k pots on the front.

I went to a local electronic shop nereby and was told that 50k´s were not available not even manufactured (but for audio use about 5 times the price)only 47k´s and was suggested a 3k resistor in series. WTF?

Also I have been thinking about the physical aspects of theese pots, Isn´t it desirable to have a pot that does let´s say a 3/4th of a whole 360 degrees.
I think this is what is on most gear out there no? How to deal with this?

Best

F

 

[Axelerator]

:grin: Hello everybody , this is my first post.. a few words: great Forum.., about one and ahalf jear i searched the net for "what is class a" ..now I see 2 stuffed 1176 (not cabled yet) and a (point to point ? its on a card but almost..) G-SSl in front of me..(could not wait for pcb ..)

.. and when i look
on the schemo i see i maybe forgot the 1K which is connected to p.3 (+)of the 5534 in the vca emu circuit , i have jused just one 1k in every cv-chain after splitting up
so if i see right i have to use one more (2K) of them!? or is the 1K resistor on the emu -circuit the one going directly in the dbx cv in?


- Just saw another thread where differences between the schemo and pcb version were told ( i have to change the 100p to 100n also in the emu-circuit) so does anybody know what more i should change..?


so thanks for all your help , i think i never would have tried soldering vintage(or anything..)gear without knowing you all are out there.. :!:

 

[gyraf]

Hi Ax,

If you stuff the PCB board like the silkscreen says - with the possible minor upgrades/changes for THAT218x-series vca's - you should be alright.

If you read through this long thread - and the related threads in the "SSL Meta" - see the "meta-meta" on the top of this page - all your questions (and then some) will probably be answered.

Jakob E.

 

[byoung]

I am working on my first G-SSL unit and have 2 questions that I have not been able to clarify after much searching of the forum and research, first one I posted in the 2181 calibration thread and haven't heard anything for days so I will repost here.

It seems that some people who are using 2181xx's are removing the 68R next to the VCA's, replacing the 10K next to the VCA's with a jumper, and then replacing the 1M below the VCA's with a 220K, As well as changing a couple of resistors in the sidechain. Are these neccessary or recommended? I'm using 2181LA's with a 2181LC in the sidechain.

Secondly I'm am curious how to wire the XLR in/out jacks to the board. On the Bal Input/Output connections there is the +/-L 0 -/+R Does that mean I should tie the shield or third wire from the L/R XLR's together and connect it to the 0 on the board or am I missing something?

Thanks for any help.

Brian

 

[AudioguyII]

Hi,
building my next round of GSSL.
Just wanted to check , there are 1k* resistors needed in each VCA channel, what does the * stand for, there is no legend for it. I put 1k in early model. Should I do it again.

Also, it seems my first gssl boosts the output by about 5db even with the make-up gain all the way down or the bypass switch enabled.....
Anyone know the reason for this? How can I make it be unity gain with input when bypassed? Or when threshhold is set to no compression?

Thanks for a great community and all the help!!!!!

AudioguyII

 

[AudioguyII]

To add to the above...

I'm using THAT 2180LA VCAs.

Thanks,
AudioguyII

 

[byoung]

I found out what I needed to know after reading somebodies personal webpage about the 2181LA changes. So I'm good there but, I still am curious about the wiring and grounding of the XLR jacks, I guess I'll just try and hope that nothing blows up.

Audioguy...as for the 5db of gain there is a unity gain mod in which you change the 2 15k resistors above the VCA sections on the board to 27K at which point you are supposed to have 0db unity gain. There is a thread about it in the SSL Meta section.

 

[AudioguyII]

Thanks for the help.
Funny...I just read it in a post .

Also, since I'm using the 2180LA... I saw that removing the two 10K, the 68R and the 1M, then changing the 3K9 to 5K1 is appropriate.
Can anyone confirm this please.

Is there anything else I'm missing that could improve things.

Once again! Thanks!!!

 

[Oli Q]

Hi,

I've got a slightly odd problem on my SSL, stereo operation works fine (and sounds wicked), but if I run it in mono using just the left side then turning up the makeup gain increases the gain reduction until the meter peaks out. Strangely this only happens if leads are connected to both sides. If I only plug in mono input and output then its fine, but both plugged in and signal only going into one side it behaves like this....

Not too bad but means I can't use it in mono with a patchbay... anyone got any ideas?

Oli

 

[JAYJAYBEE]

Hey there, quick question.

Can I use this transformer for the ssl comp

http://uk.farnell.com/jsp/endecaSearch/partDetail.jsp?sku=9531670

Only its 15VA and all ive read says 10VA...farnell doesnt have a 10VA, i think
.

Thanks

 

[JAYJAYBEE]

Also is this ok for the poly caps. Im a little bit unsure because of the differences between AC voltage and DC voltage values.

http://uk.farnell.com/jsp/endecaSearch/partDetail.jsp?sku=1100591

thanks again

 

[JAYJAYBEE]

Sorry i meant this one

http://uk.farnell.com/jsp/endecaSearch/partDetail.jsp?sku=1189289

 

[sintech]

JAYJAYBEE,

That power trafo is going to be tight in most 1u racks by the time you've added a bolt. I used this Farnell part number: 9532161 works great and a fixing kit is included!

 

[JAYJAYBEE]

Hey thanks a lot sintech.

Any word on the caps link i posted.

 

[sintech]

Those poly caps should be fine :thumb:

 

[W DeMarco]

I am certainley loving my GSSL but one or two things are buggin me. My 15 volt rail is not quite 15 volts. My 15 readings are

- 15 rail = -15 volts
+15 rail = 14.7 volts

I think I read somewhere that a couple tenths off isnt bad but this is a few. Wondering if that changes anything. Today I am gonna swap one part at a time on the +15 rail in the hope that I can find the problem. I already swapped out the 7815 and 22u cap directley in front of it .

2nd worry was that it seems to be louder or quieter on one channel. Im hoping the problem is in the voltage being low but I doubt it. Now that I have it on the bench Ill dig a bit deeper onm the 2nd problem.

BTW, My bigtime producer/engineer friend was in CLE workin with me on a couple of projects. I showed him this compressor and he freaked out and started tellin me all about how much he loves the original, I told him this one was 350 bucks or so to build. He was jealous!!

:thumb:

After I tech it out Ill post pics and all. Right now we call it the feelimiter because of the lack of markins and meter!

Will

 

[Greg]

Your voltage rails are fine... I wouldn't worry about them.

However, having one channel louder than the other is a problem. First, check your input and output wiring. It's common to lose either the + or - leg.

 

[W DeMarco]

Right on

The first think I noticed was that the trace from output L- to the first resistor to its right was worn. I made a jumper npw all is well. So problem solved!! Now onto mods for 2181 LB

Thanks

 

[tommypiper]

I'm still struggling to get this GSSL working, I think this is a new record!

I inherited this board from a guy who had stuffed it but could not get it going. I have found three broken pads and traces - but which were invisible until I began removing parts. So there may be more hidden problems like that and why it's still not working. I also found 6 wrong capacitors, backwards wiring, switches in backwards, 1 missing jumper and cold/broken joints! :evil:

I should have thrown the board away and started a new one. (I will soon if it's not working after this.)

Thanks to all who have helped.

Here's my current question:

I am removing the VCA parts and installing dbx 202s. What parts do I need to keep on the board in the VCA sections?

Do I use resistors in the area near the pcb edge as marked (1 meg, 1k)?

Do I clear out everything in the silkscreened VCA boxes?

Do I need the trimmer pots?

Thanks.