SSL 4K channel dynamics. (And more in future). PCB's/kits: Available!

[seancook]

Hi, does anybody happen to have a mouser cart for this?

 

[Electrobumps]

This one is a bit of a pain.  Not all this is available at Mouser I had to order from 4 places.

From memory, but confirmed in the Bom

LED's and some other bits are Farnell only. 
The push switches and switch caps are DigiKey
Switching pots, all of the above suppliers mounting diameter was much larger than chassis and front panel.  had to source these from ebay.

To be honest it is a really annoying build as terms of information, ordering parts and the layout of the boards.  However it's worth because they sound cool. 

Although I do not believe the i/o levels are quite right.  The bom does offer an alternative input IC's which gives +6db and much more usable compression (my DAW is -14dfs @ 0vu), I tried this and it is great, but my o/p was way to hot.  I can't remember is there is an alt o/p IC.  As this will need to be matched on the o/p for unity gain, or a level dropping resistor added if you want unity gain.  One day I will look into this further.

 

[seancook]

Yeh, had a fun time going through and finding all the parts, i think i have most everything ordered and on its way to me!
We will see once i have all the parts in front of me.

The only thing i need to get are the pots, specifically I cant find any info on the size? and the 250k log switching pot seems like it might be tough to find.

any pointers?

 

[jasonallenh]

I'm sourcing all my components for this... but I can't find the AAZ17 germanium diode anywhere in the US... is there a US equivalent floating around here somewhere?

 

[jasonallenh]

Looking for confirmation that this would be a suitable relay-

http://www.mouser.com/ProductDetail/Omron/G5V-2-H1-DC12/?qs=%2fha2pyFaduiP%2fpKRK%2fe1cZnYuWBwNRH7xYhpU%2fxru0KyJlE%252bha9jXw%3d%3d

The specs aren't all the same, but the footprint, switch contact arrangement, and coil voltage all seem close.

=jh=

***I edited the post to switch the link to the high sensitivity version of the relay. The datasheet lists this one at 960 Ohms coil resistance, which is more than the 700 ohms specified in Igor's BOM.  What say you guys????

 

[seancook]

i grabbed a bunch of bits, including that diode, from ebay

 

[jasonallenh]

i grabbed a bunch of bits, including that diode, from ebay

As did I. The guy gave me three instead of the two that I orderered... I'm quite pleased. I have now ordered ALL my parts (Including metalwork from Frank). As soon as I assemble a module and can confirm that it is working properly, I'll post a full and proper BOM for US builders.

 

[seancook]

the only things im struggling with is the switches, they have weird common pins and only seem to be available from digikey or mouser.  The other one is the "wire to pcb" part of the 10 pin connector to the meter board, that farnell number is no longer working and as its a tight fit in there so I would like to get the appropriate part.

Any help on details of those parts or are there any alternative parts i should be looking at?

 

[jasonallenh]

the only things im struggling with is the switches, they have weird common pins and only seem to be available from digikey or mouser.  The other one is the "wire to pcb" part of the 10 pin connector to the meter board, that farnell number is no longer working and as its a tight fit in there so I would like to get the appropriate part.

Any help on details of those parts or are there any alternative parts i should be looking at?

I'm assuming the switches you're referring to are the relays. This is what I ordered, and the footprint is right on the money. The switch contacts appear correct too. A Mouser tech cross-referenced the datasheet for the relay in Igor's build pictures and he came up with the same part number, so while I haven't tested it personally, this one should work:

http://www.mouser.com/Search/ProductDetail.aspx?R=G5V-2-H1-DC12virtualkey65300000virtualkey653-G5V-2-H1-DC12

The R_Rel value for these (900 Ohm coil resistance) works out to a clean and tidy 100 ohms.

For the wire connectors, this is everything. Male/female headers (based on the exact farnell part numbers igor listed) and a length of the correct sized ribbon cable. It's not the cable igor specified (that is only available in like a 50ft or 100ft length), but it's the right pitch.

http://www.mouser.com/Search/ProductDetail.aspx?R=1-215911-0virtualkey57100000virtualkey571-1-215911-0

http://www.mouser.com/Search/ProductDetail.aspx?R=3365%2f10-CUT-LENGTHvirtualkey51750000virtualkey517-3365%2f10FT

http://www.mouser.com/Search/ProductDetail.aspx?R=09195107324virtualkey61720000virtualkey617-09-19-510-7324

Hope this helps.

=jh=

 

[tomas1808]

I think he's talking about the 'Gate' and 'Link' push switches. They are not your standard 'common-pins-in-the-middle' switches.  Not too sure why Igor decided to use those. I ended up using standard toggle switches offboard because I am not using the official metalwork. 

If you plan on using the frontpanels you are pretty much forced to get the required switches. Or maybe you could cut some traces on the small board and add some jumpers so you can use standard switches. A bit tedious probably...

 

[G-Sun]

Has anyone finished theirs? Pictures?
Any opinion on sound and usability?
Good/bad on certain instruments?

What features are there?

This is described as a hard build, so..

 

[jasonallenh]

Has anyone finished theirs? Pictures?
Any opinion on sound and usability?
Good/bad on certain instruments?

What features are there?

This is described as a hard build, so..

I have all the parts ordered, but I haven't had time to finish just yet. I should have a complete module within a few days. I have already discovered some parts that won't work (my meter LEDs are too big) so there may be some delays. There are also a handful of BOM discrepancies. I'm taking notes as I go.

 

[jasonallenh]

I have realized that the 10-pin connector can only go on one PCB. I put one on both the main and meter pcbs, and it made them both too tall to fit in one slot. Mechanical stuff is both tight and exact in this build. I've got to throw on a few missing parts, then wire all the pots and I'll have one complete unit.

 

[jasonallenh]

Here's my calibration procedure per the SSL documents and Igor's schematic. Please feel free to correct anything I got wrong, because I am far from 100% sure I've done this correctly...

1. Set the compressor to the settings specified in the documents.

2. Send a +14 dB 1k sine wave (this is the first part I may have done wrong... I'm assuming this is in dBu, which according to my console manual is -4 dBFS. I set my DAW sine generator to -4 in this case to make the +14 dB).

3. Read the signal out with the unit in bypass. It was coming back into the daw at -4.3 dBFS.

4. Engage the compressor and use VR2 (Schematic and SSL docs refer to this as the 0dB preset) to change the output level to 4db below the level you get in bypass. For me, that meant I set it to -8.3 dBFS when reading the output in my DAW.

5. Turn your threshold control all the way down (-20) so that you're seeing the GR maxed out. Back your sine wave off until you see no compression. Clear your meter peak in your daw.

6. Raise the sine level until you see the first GR meter LED come on. Take a look at the peak reading in your DAW at this point. (Mine was -25.5 at this point).

7. The SSL Docs say that the level should stay fairly constant (within +/- 1 dB) as you raise the sine level from here (because your ratio is at infinity). Mine did not do this at first- Once my compressor started limiting at -25.5, the level made it up to like -23.9 or something like that. This is how you know you need further adjustment...

8. ...in which case, the documents tell you to adjust the "gain preset" (I guess 'preset' means 'trimpot' in British... I speak American =P). The trimmer in this case is VR1... You'll adjust VR1 to correct this.  Lower your sine level until there is no more Gain Reduction, then clear out your DAW peak meter again. Raise the sine until you see some GR, make note of the peak level at that point, then continue raising. If the output level doesn't go past 1dB, you've made the correct adjustment. If it got WORSE, you need to turn the trim pot the other direction =P

9. Once you've met the condition that the output stays within +/- 1dB of where it is when GR begins, your compressor is set! Change your ratio to the lowest setting (1:1)

10. Set the expander settings to those specified in the SSL docs.

11. Generate +14dB at 1K (once again, I'm calling this -4dBFS in my DAW... I may be completely wrong about this).

12. Adjust VR3 until the signal passes through the gate. (this was easy). Once this is done, put your range control to its minimum setting.

13. Sym Adjustment. I stumbled upon this by accident! The output, when viewed in the cubase channel settings, showed multiple harmonics of 1k (2k, 4k, etc). This is the distortion that the SYM trimmer is supposed to remove (I guess... tell me if I'm wrong!) I'm including an image of what it looks like before adjustment.

14. Adjust the SYM preset until those extra harmonics go away. If you go too far, they begin to creep back up. Find the happy medium.

15. ALL DONE!? EDITS?

 

[ho-fi]

Has anyone finished theirs? Pictures?
Any opinion on sound and usability?
Good/bad on certain instruments?

What features are there?

This is described as a hard build, so..

I finished 2 pcs. they're awesome!
i used to work on a SSL 4k g+ for several years and still do from time to time.
compared to the original, they lack of nothing, i like it even better than the original 4k dynamics.
my go-to comp for kick/snare and the expander/gate is also doublesupermega awesome (scientifically said). 

 

[ho-fi]

omre asked me for a mouser cart for this project.
here it is. at least a partial one.
look if there are any vishay/dale resistors and replace them with different ones. (they don't fit the pcb...)

here's the relays mouser no. 653-G5V-2-H1-DC12

the led's i sourced from distrelec.

cheers, ho-fi

 

[omribgr]

ombre asked me for a mouser cart for this project.
here it is. at least a partial one.
look if there are any vishay/dale resistors and replace them with different ones. (they don't fit the pcb...)

here's the relays mouser no. 653-G5V-2-H1-DC12

the led's i sourced from distrelec.

cheers, ho-fi

thank you ho-fi ! 

 

[seancook]

I'm having a bit of trouble with the calibration on these, my threshold knob has a pretty wild action, im assuming due to the lack of calibration! I've doubled checked the pot wiring and everything is all good there, the voltages seem good for the op amps. Somebody posted that i should see +/- 18v for the rms chip but im only seeing 16, but i dont think thats the issue. The internal trimmers don't seem to be doing much so maybe thats my issue? the gate works (the levels need to be adjusted to a more useful working range) but the compressor just distorts and sends the gain through the roof.
I will do some digging around and make sure the solder joints on the trimmers are ok?

 

[jasonallenh]

I'm having a bit of trouble with the calibration on these, my threshold knob has a pretty wild action, im assuming due to the lack of calibration! I've doubled checked the pot wiring and everything is all good there, the voltages seem good for the op amps. Somebody posted that i should see +/- 18v for the rms chip but im only seeing 16, but i dont think thats the issue. The internal trimmers don't seem to be doing much so maybe thats my issue? the gate works (the levels need to be adjusted to a more useful working range) but the compressor just distorts and sends the gain through the roof.
I will do some digging around and make sure the solder joints on the trimmers are ok?

Did you use a linear or audio pot for the threshold knob?

 

[seancook]

i used a linear pot for the threshold and ration, log and pull switch for the attack/release