Whoops

Re: SSL 4K G-Series Mic Preamp
« Reply #40 on: February 20, 2017, 10:35:24 AM »
Nice Work, thanks
« Last Edit: March 04, 2017, 08:58:03 PM by Whoops »


dustbro

Re: SSL 4K G-Series Mic Preamp
« Reply #41 on: February 23, 2017, 03:56:03 PM »
finally shipped! should be in my hands soon

Pusch3l

Re: SSL 4K G-Series Mic Preamp
« Reply #42 on: February 23, 2017, 04:36:58 PM »
Your layout looks pretty nice.
Anyone wrote down a BoM yet?
Dustbro, can you explain the "ConnX" a-e connections a little bit?

dustbro

Re: SSL 4K G-Series Mic Preamp
« Reply #43 on: February 23, 2017, 08:35:38 PM »

Anyone wrote down a BoM yet?


I'll supply a BOM and build document with the board.

The ConnX is the connection to gain rotary switch.

Potato Cakes

Re: SSL 4K G-Series Mic Preamp
« Reply #44 on: February 24, 2017, 01:02:34 AM »
Awesome! Can't wait!


Pusch3l

Re: SSL 4K G-Series Mic Preamp
« Reply #45 on: February 28, 2017, 03:30:32 AM »
Maybe someone in EU is interested in ordering these:

http://store.solidstatelogic.com/node/13352

Set is for a 4 Channel Pre, so it could split up  :)


alexc

Re: SSL 4K G-Series Mic Preamp
« Reply #46 on: February 28, 2017, 05:20:54 PM »
Very nice work  there :)

I'd be really interested in putting a couple of these together just to measure them!
I ping therefore I am

dustbro

Re: SSL 4K G-Series Mic Preamp
« Reply #47 on: February 28, 2017, 08:43:26 PM »
Very nice work  there :)

I'd be really interested in putting a couple of these together just to measure them!

PM me your address

alexc

Re: SSL 4K G-Series Mic Preamp
« Reply #48 on: February 28, 2017, 11:01:29 PM »
DOne :)
I ping therefore I am

signalflow

Re: SSL 4K G-Series Mic Preamp
« Reply #49 on: February 14, 2021, 12:36:06 PM »
Resurrection time.

Did anything ever come of this project once the prototypes were ordered? All docs seem to be removed except for the original schematic provided by Whoops. Curious to know if any were built or PCB's made?

Thanks,
Casey
The shortest distance between two places is a nap.


Ricardus

Re: SSL 4K G-Series Mic Preamp
« Reply #50 on: February 14, 2021, 01:56:24 PM »
I'm curious too.
Audio mastering for hire..

Whoops

Re: SSL 4K G-Series Mic Preamp
« Reply #51 on: February 14, 2021, 11:10:23 PM »
Resurrection time.

Did anything ever come of this project once the prototypes were ordered? All docs seem to be removed except for the original schematic provided by Whoops. Curious to know if any were built or PCB's made?

Thanks,
Casey

New developments here:
https://groupdiy.com/index.php?topic=42552.660

signalflow

Re: SSL 4K G-Series Mic Preamp
« Reply #52 on: February 15, 2021, 10:15:57 AM »
New developments here:
https://groupdiy.com/index.php?topic=42552.660

I've seen the thread but wasn't sure he used the actual G+ schematic. He mentions the transformerless E series preamp(149) which has 2 matched transistor pairs instead of the 1 pair the G+(291) uses.

To clarify a bit I use

SSL 82E149 transformerless thats formerly also a E Series but with two LM394, The G series is a bit similiar from that circuit design.

SSL 82E01 Transformer based with JT115K-EPC like the original used on the cards

and the SSL 9k found in the SSL tech docs

I will use switches for gain for all my designs

I PM'd Dustbro but no response.  The G+ does "resemble" the 9K. Like they got to a point and just said ...meh. I'll stare at if for awhile and see if it goes anywhere. My main question was the gain switch wiring. Seems that will be a bit of experimentation if it ever gets that far.

-Casey
The shortest distance between two places is a nap.

Whoops

Re: SSL 4K G-Series Mic Preamp
« Reply #53 on: February 15, 2021, 01:57:58 PM »
I've seen the thread but wasn't sure he used the actual G+ schematic. He mentions the transformerless E series preamp(149) which has 2 matched transistor pairs instead of the 1 pair the G+(291) uses.

I see what you mean...

You should ask that to Kevin in the relevant thread.

This thread has no activity since 2017, so it's better to consider it dead and move on to the new developments.

I still have some dustbro pcb's, pm me if interested
« Last Edit: February 24, 2021, 11:21:50 PM by Whoops »

Ricardus

Re: SSL 4K G-Series Mic Preamp
« Reply #54 on: February 25, 2021, 06:17:14 PM »
Is VR1 that drive circuit that was being talked about earlier in this thread?
Audio mastering for hire..

signalflow

Re: SSL 4K G-Series Mic Preamp
« Reply #55 on: February 25, 2021, 07:54:56 PM »
Is VR1 that drive circuit that was being talked about earlier in this thread?

No. This looks to be a CMRR adjustment.

The circuit you're referring to is the VHD(Variable Harmonic Drive) circuit found on their newer rack gear and Duality console.

-Casey
The shortest distance between two places is a nap.

Ricardus

Re: SSL 4K G-Series Mic Preamp
« Reply #56 on: February 25, 2021, 08:52:44 PM »
I was sent the docs for this project, and one of the PDFs showing a front panel layout had two pots per channel. This confused me.

What exactly am I measuring to perform the CMRR adjustment?
Audio mastering for hire..

signalflow

Re: SSL 4K G-Series Mic Preamp
« Reply #57 on: February 25, 2021, 09:10:30 PM »
Having just seen the docs today, thanks to Whoops, I may have mistaken your question. The added Pot on the front panel is an output level control. What I thought you were talking about was the trimmer located right after the diodes at the input.

-Casey
The shortest distance between two places is a nap.

Ricardus

Re: SSL 4K G-Series Mic Preamp
« Reply #58 on: February 25, 2021, 11:39:39 PM »
Having just seen the docs today, thanks to Whoops, I may have mistaken your question. The added Pot on the front panel is an output level control. What I thought you were talking about was the trimmer located right after the diodes at the input.

-Casey

I was talking about the trimmer. But I don't see any documentation about where the output pot goes in any of the stuff I have.

But when adjusting the trimmer pot for CMRR, what exactly and I measuring and comparing? Am I just running a sine wav into it and matching signal levels on either side of the pot?
« Last Edit: February 26, 2021, 12:04:47 AM by Ricardus »
Audio mastering for hire..

Whoops

Re: SSL 4K G-Series Mic Preamp
« Reply #59 on: February 26, 2021, 05:32:06 AM »
But I don't see any documentation about where the output pot goes in any of the stuff I have.

It’s in the schematic I sent you,
a 10K Pot at the output before U6