Holger's Green Line cont'd (GSSL)/Pics

[Holger]

Just finished a nice looking GSSL with an old Weston meter.
It has some modifications like Turbo board. I left out the 0.1µF in the I/O section per Kingston's suggestion. I replaced the 5532/5534 with OP604/2604. I am also testing some output transformers, starting with old Altecs here.

 

[[silent:arts]]

your compressor rack must be huge now ;D ;D ;D
don't tell me you produce anything with them, I know you have a day job, and I know how much time DIY takes :
your output is incredible

and always this clean work, and those nice looking designs 8) 8) 8)

great work, congrats

 

[ultra-alex]

looks great! i really like that style. congrats.
cheers, alex

 

[livingnote]

We appear to be having a lot of fun tormenting that same old box, eh?

Nice job. I love that meter.

 

[Kingston]

I replaced the 5532/5534 with OP604/2604. I am also testing some output transformers, starting with old Altecs here.

Since you're out to do opamp swaps, the I/O section is the nice first touch, but there's more you might want to experiment with.

Try OPA404 as the quad opamp. Remember there's one on the turbo board as well. While a modern opamp in the I/O section will clean up t hings a lot, OPA404 actually changes compression characteristics. The TL074 is "too slow and distorted" for the sharp rectified audio discontinuations. While it results in the familiar SSL punch sound, it's obviously distorting in many ways, most obvious on fast attacks and stereo imaging. OPA404 takes the compression more into the mastering area.

I went further and tested OPA604 as the VCA driver's as well. Surprising compression characteristic change, again obvious on fast attacks and imaging. Some would say it makes no difference just how crappy opamp drives the control signal, but don't take this from me, and hear it yourself. It's not subtle.

 

[Kingston]

I see you are using 100nF as the VCA driver opamp feedback cap. Whoops! Did you at least try 100pF (or even 47pF) first?

I know the 100nF is a commonly accepted recommendation, but damn, it sounds like *****! It completely kills the accuracy of the control signal, and this is no subtle difference. You can't have fast accurate attack with 100nF at all and even release will become "restless".

I seem to recall you have more than one GSSL built. Compare them side by side. You will be surprised.

 

[Holger]

Kingston, thanks for the suggestions. I will try them.

 

[Holger]

your compressor rack must be huge now ;D ;D ;D

Little bit off topic, here it is

 

[livingnote]

Look out America, the Germans are at it again  ;D

 

[drpat]

...

 

[livingnote]

Wax on...mouth off

...for a while there as a kid there was nothing I wished for more
than a phial of ooze. Or at least a job at TGRI.

Man, that was back when we lived in Davis. I really miss the place...

Respect for your rack of course, but I didn't mean it quite that way -
I was thinking more like I might warn the Pentagon they weren't
thorough enough in '45 when it came to Das Boot. Ten more
years of ol' Holger and it'll be Hemp For Victory all over again...

 

[Snatchman]

your compressor rack must be huge now ;D ;D ;D

Little bit off topic, here it is

Amazing...!

 

[mingus]

hmf! and here I´m still sitting 1 year later and wondering how to get the psu wired up for 230V.

Instant rookie feel.

Great job there!

m

 

[mylesgm]

Want to go through what the rack of gear actually is?  Those builds look great!

 

[pietro_moog]

hi Holger.
how do you make your panels?
you paint them yourself and then Schaeffer?

 

[Holger]

Usually I'd let them paint at a local paint store, the engraving is done by Schaeffer or Frank/NRGRecording.

 

[sonicwarrior]

I see you are using 100nF as the VCA driver opamp feedback cap. Whoops! Did you at least try 100pF (or even 47pF) first?

Is that the 100n between the opamp and the VCA?
The other two 100n look like they are just for decoupling (between ground and +15V or -15V).