DIY 500 series STUDER 169 Recording Channel (Mic Pre + EQ) Documents Published!

Help Support GroupDIY:

SoundOfRolf

Active member
Joined
May 16, 2015
Messages
27
Location
Helsinki
Hi!

I've finally got a board etched and am filling it. Audiox, did you have some smart idea how to utilize those extra pads for switches?  Or just wire off board? Mostly interested in phantom, pad, polarity and maybe hpf.

-Tony
 

SoundOfRolf

Active member
Joined
May 16, 2015
Messages
27
Location
Helsinki
Yes PCB's would rock!

I etched one and built it. It's not pretty but it's working. I would rather take a factory made PCB though.

I thought I made some heavy mistakes or built a radio as there was some strange noise and it started oscillating like crazy on higher gain or frequency gain settings. Turned out to be the Lindell 510 rack. Moved to a slot further away from the PSU and voila works as expected. Low noise, huge gain. Need to do that pad. I wired a switch for the phantom and added a red LED with 10k resistor.
Should the LED be connected to ground or chassis? Or is the only down side connecting to ground the pop that it gives when turing on? (chassis so far away......) :)

Thanks for the project! I'll do at least one more....waiting for some brave to have some PCB's manufactured.

-Tony
 

zayance

Well-known member
White Market Member
Joined
Feb 25, 2009
Messages
2,294
Location
France/Swiss
Hi There,

What equivalent for BC239 do you guys use?
Or maybe someone have some spares?

Thanks in advance

Best,


T.
 

iprovlek

Well-known member
Joined
Sep 6, 2010
Messages
720
Location
Zagreb,Croatia
I try BC550c and BC109C!

With this two I get more Bass!BC239 has less bass than BC550 and BC109!

This preamp is amazing!I use him on everything!Planning to do 12 channels of this!

It would be great to use PAD,HIPASS FILTER,+48V,LINE,PHASE and differnete freq on high and low freq!
 

zayance

Well-known member
White Market Member
Joined
Feb 25, 2009
Messages
2,294
Location
France/Swiss
Good to know.

RS has tiny toggle switches that take very little space on frontpanel.
ref:ZL36S0101
 

SoundOfRolf

Active member
Joined
May 16, 2015
Messages
27
Location
Helsinki
audiox said:
Note. Options not shown for clarity. I will draw separate wiring diagrams for the numerous options.

It would be nice to see these and compare to what I did.

BTW there seems to be some DC offset (~50mV. The 169 EQ's I built have 100mV). How to trim it or should I put some output caps or just never mind it?

;)
 

SoundOfRolf

Active member
Joined
May 16, 2015
Messages
27
Location
Helsinki
I'd like to share my front panel if somebody would have any use for it.
I wouldn't recommend to use it as is as it has really small clearance for the text as you can see in the photo above.

It's not fully my writing. I used a panel from the EQ thread and modified it with help from Frank who also produced the panels.
Thanks for that.

I'll try to attach it here as linking to outside services tend to stop working with time.
Just change the extension to .fpd
 

Attachments

  • Audiox Recording Channel Front Panel.brd
    1.9 KB · Views: 55

Vac11

Well-known member
Joined
May 2, 2014
Messages
329
Location
Czech Republic
Hi all,

can I use for mids  (frequency and gain) concentric pot with these parameters?

2x 100K rev log (for frequency sweep), 1x 10K linear witch center tap (for +- gain)

When I add a 10K resistor parallel on 1. and 3. lug on the 10K gang, everything could be Ok...  Or not?

Thanks

M.
 

audiox

Well-known member
Joined
Feb 25, 2007
Messages
610
Vac11 said:
can I use for mids  (frequency and gain) concentric pot with these parameters?
2x 100K rev log (for frequency sweep), 1x 10K linear witch center tap (for +- gain)

The P5 value is not critical. A single 10 kohm potentiometer should be fine.

 

Vac11

Well-known member
Joined
May 2, 2014
Messages
329
Location
Czech Republic
Mounting on the L-bracket is possible to... Here is another possible solution:

https://drive.google.com/file/d/0B_XBYPfmG8pVMjVkMDYzNTEtYzdhMS00ZDlkLWJjNWMtZGZjMGFiODAzYTNl/view?ddrp=1&hl=en#
 

Jano1954

Member
Joined
May 20, 2015
Messages
16
Can you tell me who sells the knobs you are using Sound of Rolf?

What is the make, modelnumber, partnumber and where to order?
Thnx
 
Top