SSL 9K Mic Pre Thread 2009

HELLO TO EVERYBODY
as suggested by the "cool" Admin
here a 2009 - ssl 9k project thread
the reason about , is that the first thread in meta page
don't work anymore .
and then make a new thread with complete helps for 9k project
thanks from now to some guy like
neeno
ssltech
........

that in the past just have worked on the 9k and posted docs.
here the 9k basic infos :
http://www.studio21.ch/diy/neeno/ssl9k/DIY_9k_Preamp.pdf

Note about Bom from "uncle":
.pdf BOM from 9k thread is fine. Just Add 100nF for Cy in micpre. And correct c6-c11 from 100uF to 100nF in power supply. I bought allmost all parts here in Belgrade, Serbia, so unforunately I can't help you with farnell codes. Only OPA604, LM394 and silvered mica caps were ordered from farnell. You can use any ceramic caps instead of silvered mica, because they are not in audiopath, I made mistake on my project
--------------

and thanks to:
anyone want to give help to who start today with 9k project ,
or update old docs , as :
updated bom list , infos about parts sources , projects and details pictures ,
building tips-tricks , ecc..

more thanks in advance
have a nice : 9k project
6T9R
-----
ps
update 1 (thanks to milkmansound):
SSL9K BOM (for the US it looks like)
http://www.milkmansound.com/img/SSL9Kparts.xls

update 2 for anyone have psu problems:
http://www.groupdiy.com/index.php?topic=4312.0

Here we go 6T9R... sorry for the delay but I've been busy with work.
Here is the link to the ssl9k documentation.

http://www.studio21.ch/diy/neeno/ssl9k/DIY_9k_Preamp.pdf

I hope it helps !

WELLCOMEBACK
NEENO
Thanks for add!!!
have a nice day
6T9R

Hi All,

I'm waiting for my ssl9k boards to arrive. Meanwhile, could anyone tell me about the dimensions of the preamp and balancing board.

Thank you very much

JAY X

Preamp: 80 * 125 mm
Bboard:  70 *32 mm

hi group,
well, who'd have thought I'd still have baffling problems on my now 7th SSL build....
basically the preamp works as expected at gain settings up to "12 o'clock", after this point the signal gets clipped and quieter as I keep turning up the gain. At first I thought that I had the dual pot wired wrong and was turning one stage down as I was turning the other one up. This is NOT the case.
I tried to scope around the circuit a bit, and measuring at the connected legs of the second stage gain control (aka top of R81 in the schem) I get the following scope pictures:

gain below halfway:

gain above halfway:

apologies for the huge blurry mobile pics. any help much appreciated!
cheers
briomusic

The only problem i have with mine its that i have some smalles oscillations around 16 o'clock.
Weird huh?

3nity said:

The only problem i have with mine its that i have some smalles oscillations around 16 o'clock.
Weird huh?

Click to expand...

Do you mean it occurs around 16 o clock and disappears again? or present all the way after this point?
it's a pretty high gain setting, what is connected to the input?
I only have weird oscillations/hums with some transformerless mics.

Anyways, with my own snag, I checked the pots and the ICs, that doesn't cure it
Can't find any bad solder points either. guess next is checkin all the resistors if noone else chimes in with a magic explanation :-\

SIXTYNINER: Just Add 100nF for Cy in micpre.

Click to expand...

Do you mean Cx?

briomusic said:

3nity said:

The only problem i have with mine its that i have some smalles oscillations around 16 o'clock.
Weird huh?

Click to expand...

Do you mean it occurs around 16 o clock and disappears again? or present all the way after this point?
it's a pretty high gain setting, what is connected to the input?
I only have weird oscillations/hums with some transformerless mics.

Anyways, with my own snag, I checked the pots and the ICs, that doesn't cure it
Can't find any bad solder points either. guess next is checkin all the resistors if noone else chimes in with a magic explanation :-\

Click to expand...

If by any chance you have mixed up resistors or have a wrong resistor near the input, that would probably cause unwanted noise.
The gain pot wires should be twisted against each other...I managed to lower the noise floor this way some decibels, and basically there's no hearable noise on mine when there is a mic connected.

This is probably something you all know anyway, but I guess it doesn't hurt mentioning it: Turning the power transformer will help with hum if there's any.

Nice to see a up to date thread being created.

I have 4 boards sitting at home waiting to be housed in a 1U case. The only problem I am having with this project is finding a supplier for the MAT transistor.

The only supplier I found is Digikey and they only have 3 left when I checked a few weeks ago.

Does anyone know where I can find a retailer? Maybe someone on this forum? I'll probably need 8 cause I'm planning on building 4 more of these bad boys...

J

Hi Matthew!
IIRC you can sub MAT02 with LM394 (way less expensive) , to source one or the other , check EvilBay!
(Maybe I have a few MAT02 left , do you want me to check?)

Oui Oui, merci beaucoup...

BTW, what does IIRC mean? I've seen it many times but don't really know what it means.

Thanks for the quick reply, I would love to use the MAT02 if you got some left. I guess you used them in your build. Have you also used the LM394? Does it sound similar with the LM394 or is there a loss/increase in quality?

J

If - I - Remember - Correctly

I do not used the LM394 , but have bought some because of the price...then (after a succesful test with MAT) I've bought more MAT.
I have for sure 6 LM and 2 MAT ...pm me !

I think I just saw a "life time buy" on LM394's, so I guess it's bye bye.

I went with an Analog Devices SSM2210 for another project - we'll see how it goes

Ok, I am on the 3rd day trying to fix my problematic channel, would be very thankful for some help....

something is wrong on the 'cold' audio rail, instead of the usual voltages on the transistor (C -12.14V, B -0.71V, E -.77V) I have a 2-8 Volts on the Base, adjustable with the gain pot (higher gain =lower voltage). the 'hot' side of the same transistor is normal. I also get a lot of scratchy noise on the pot, due to the DC that somehow got in there. What on earth is going on?

I have this problem on two preamp cards now, however, right next to it - using the same power supply - sits an identical card that works fine.
???  ???   :-\

Hi,

My question is: ??? what changes need to be made to use a 5k reverse audio Pot instead of the 2k5? Or what would be the difference? As i am sure most people have found the 2k5's are difficult to find or expensive! Omeg quoted $6.40 each for an order of 10 of their 2k2 reverse audio pot's with a 5 week lead time!

Also where is the best place in the US to order the MAT-02? Has anyone had success with the LM394?

Thanks!

mpc3000limited said:

As i am sure most people have found the 2k5's are difficult to find or expensive! Omeg quoted $6.40 each for an order of 10 of their 2k2 reverse audio pot's with a 5 week lead time!

Click to expand...

Have you tried AML?

http://www.audiomaintenance.com/acatalog/potentiometers_carbon_20mm_diameter_dual_gang.html

2,58£ each ...

Rednoise, did you get my PM about the MAT02?

J

Why two different SSL9K threads? http://www.groupdiy.com/index.php?topic=11320.320