New 'ultimate' SSL buss comp clone ;-)

[SSLtech]

Oxford mode requires two identical sidehain paths ALL THE WAY up to the rectifier. -To do this, you need TWO frequency-shaping sidechain boards if you're using them.

GSSL mode requires only one, because only one sidechain receives an audio signal in that mode.

Visit the expataudio website and look at the intsructions for the 'Turbo' for a more complete explanation. -The Turbo is the new -much simpler- way to achieve 'Oxford mode'.

You seem to misunderstand a bit... it's actually IMPOSSIBLE to use both modes at the same time, so it HAS to be switchable between GSSL and Oxford... both at once is impossible... the signal either goes through only one sidechain or two... it can't go through only one AND two at the same time...

-Hopefully that makes some sense.

Keith

 

[radiance]

[quote author="SSLtech"].. it can't go through only one AND two at the same time...

[/quote]

Light particles/waves CAN do this if I remember correctly.

Sorry for the OT...disregard this post...

 

[SSLtech]

[quote author="radiance"]
Light particles/waves CAN do this if I remember correctly.

Sorry for the OT...disregard this post...[/quote]
Ah... wave/particle duality.

I am most comfortable with the possibility that it is NEITHER proven to be particle OR wave, but something which ACTS in a manner with some attributes of both...

...Of course, it's entirely possible that proof showing that I am either brilliantly insightful OR a complete ass may not come until long after my death, in which case nobody will likely care very much...

:green:

Keef

 

[radiance]

Ok, still have two gssl boards laying around for making an ultimate gssl.
I want to try making it with input iron as described in this thread

http://www.groupdiy.com/index.php?topic=8174&postdays=0&postorder=asc&start=0

How should I proceed with the wireing (see quote)

[quote author="SSLtech"]
Link left input + to right input - on both boards,
link left input - to right output + on both boards.
[/quote]

 

[Chrome Heart]

I installed the turbo mod into a functioning ssl clone and it behaving pretty strange. Nothing on the right, and it seems to be in full compression without any control function. When I disconnect the turbo board it works fine, any ideas would be a help.
Thanks

 

[Sleeper]

check to be sure that you have all your chips in correctly, sounds like you might have the turbo sip in backwards or something.
common mistake, happens to everybody now and again.

 

[SSLtech]

I installed the turbo mod into a functioning ssl clone and it behaving pretty strange. Nothing on the right, and it seems to be in full compression without any control function. When I disconnect the turbo board it works fine, any ideas would be a help.
Thanks

Check out the 'help with turbo' thread. -There's a pretty full writeup of a sensible troubleshooting procedure in there.

Keith

 

[SSLtech]

Ok, still have two gssl boards laying around for making an ultimate gssl.
I want to try making it with input iron as described in this thread

http://www.groupdiy.com/index.php?topic=8174&postdays=0&postorder=asc&start=0

How should I proceed with the wireing (see quote)

[quote author="SSLtech"]
Link left input + to right input - on both boards,
link left input - to right output + on both boards.

[/quote]
Just forget the iron for now. Then put the iron in last, next in line to the XLR.

Just get it working first; -Transformers are easy to add in afterwards.

 

[radiance]

Thanks Keith, .....  boards are still laying around  :-\  Not much time lately....in the middle of moving from the Netherlands to the south of France.

 

[freq_a_beat]

Hey All,

Just a question. I want to order the GSSL and the Neumann pbc's, but I'm a little lost. When I look at the list of materials for the GSSL clone, I dont know what exactly to order. There are several variances of some of these items. Can anyone give me an actual list of materials and where they purchased each? I want to build both the Neumann and the SSL. PLEASE!!!!!!

 

[helterbelter]

well, there are a few BOM's available here, IIRC greg made a few. But do you want to build the "normal" Gyraf SSL or the ultimate ?

 

[DigitalMetal]

I have the same question really,
i would like to build an ultimate GSSL, is there a full concise BOM and build guide in this thread i have to admit ive skimmed over it a bit as theres so much being discussed it gets kinda confusing at points.

Thanks

DigitalMetal

 

[killjoy]

This is my first post! Really looking to put this together! Why does it say I'm "not allowed" to view the instructions?

 

[Rochey]

Killjoy, which post/link are you referring to?

 

[SSLtech]

First post links to page 6, but in the old site URL format.

Just go to page 6.

 

[jonathanmorbin]

has anyone attempted or completed a 5.1 compressor using this design? i am really keen to give it a go but i wandered if anyone had already done one. any advice on how to go about it?

 

[AUDIO FREQ]

So here's my version of the SSL buss compressor... looks pretty normal from the front:

But inside there's a little more than you'd expect...

EDIT: See this post on page 6 for full, condensed build instructions]

Basically it's more like the console buss compressor in one significant way. Jakob's version uses a summed-mono signal which is fed to a single sidechain VCA. phase, polarity and balance affect the detector output. In the console version, two sidechain VCAs feed two detectors, and the higher output is used. Balance, polarity and phase differences are ignored.

This is not to say that Jakob's version is not as good: -it's just different. Jakob himself says that he prefers the sound of his version, but I wanted something a little truer to the original.

Since building two detectors and sidechains meant using two boards; I decided to go one step further. The VCAs I used are the 202XT's, which are each composed of 8 x SIL VCAs for noise reasons. Since they are all used in the same pole, I built the second channel in each and polarity-flipped the signal through it, re-inverting at the end, to re-sum back in the same polarity. (You have to remove one sidechan-summing resistor to prevent the signal nulling...)

The signal thus passes through the VCAs in opposite polarity, and some of the residual VCA distortion is thus canceled. -This is how the SSL 9000 J and K series console center section buss compressor does it: the "Superanalogue" version... except that they do it with half as many VCAs in each pole, since it's getting a little expensive by that point!

In addition, the output summing also increases the output drive capability, and lowers the source impedance... this thing can run full output into about 200Ω without complaining even slightly!

It's built, it's powered up, it's working and the preliminary tests show that it's dead quiet. It's also showing less distortion than my home gear can measure: I'll have to get it reound do Scenaria's and run the Audio Precision on it to get any meaningful numbers!

So here it is. Front panel will eventually be printed with the laser printer/3MSuper77 method, but fo now I'm just glad it's finished!

This is a highly do-able version, there are minimal adaptations needed to two boards to make it work, and a 2-pole ration switch is the big part difference. I'm putting it in my new rack, pictures to follow soon.

Keith :guinness:

I know this is a really old thread, but the link to "page 6" does not work. Can anyone provide the updated link, or has the thread been deleted?