Studer 169 EQ in API 500 format

[strangeandbouncy]

Hi Audiox,


    I am NOT really qualified to make this comment other than as an end user of vast amounts of outboard, and I would hate to disagree with you guys who A B'ed with 5534 and m100. After all, I wasn't there. But in my experience, you often can't hear much difference, 'til you have a long processing chain on, say a vocal, where the sibilance tends to rear it's ugly head at the end of the chain. Then, it can make a lot of difference as to what op-amp you use. I don't mean Discrete op-amp good, ic bad either . . . .


  I also like the idea of using DOA so that you can halve the input level, and operate away from the extremes of voltage swing, making up +6dB with a tranny. Also seems to make things sound a bit "faster"(wholly un-qualified statement btw!). (Could this be that the op-amp limited slewrate effectively has less effect, 'cos you are not asking it to make so much voltage gain in the same timeframe?)


    I certainly don't mean to criticise. I will be building itwith 5534 or anything else! There are I'm sure others who subscribe to the idea of a discrete in there, and personally I am itching to try out your OA10!


    Many many thanks, and Kindest regards,


      ANdyP



    . . . . there is also the Kudos of knowing that there is a discrete sitting in there . . . .

 

[audiox]

ever thought of (optional) DOA footprints (your OA10 comes to mind), or some input and / or output transformers?

Optional DOAs and input/output transformers and its a sweet unit

Add transformer I/O and DOA option and I'll build more than a pair!

There are I'm sure others who subscribe to the idea of a discrete in there, and personally I am itching to try out your OA10!

Several meetings were cancelled yesterday and I had almost a whole workday left. Well, I have electronics CAD installed in my laptop...

I added discrete op-amp option in the eq section. I am not convinced that it makes a huge difference but at least it allows to do some op-amp experiments. The pinout is compatible with API2520 and many others (including my version of Neumann OA-10 http://www.groupdiy.com/index.php?topic=34105.0 ).

I also included an option for the original Studer 169 input transformer (Studer 1.022.405.00 = Neutrik NTL1).

(See the first post in this thread for a new picture and refresh your browser if you still see the old one.)

 

[mitsos]

RE: hosting, if you don't need a lot of space you could use a free webhost.  Like PeterC's tripod page
1176neve.tripod.com

Has pop-ups but it's free, I think. There are probably others too. 

 

[[silent:arts]]

...I added discrete op-amp option in the eq section. I am not convinced that it makes a huge difference but at least it allows to do some op-amp experiments. The pinout is compatible with API2520 and many others (including my version of Neumann OA-10 http://www.groupdiy.com/index.php?topic=34105.0 ).

I also included an option for the original Studer 169 input transformer (Studer 1.022.405.00 = Neutrik NTL1)

cool, thank you.
I will take some ;D

 

[gang of elk]

i'm looking for a simple eq for a line-level console project and i think this might be the one! 

 

[matta]

Hey Audiox,

Just pointing it out as a reference, do as you see fit. We all thank you for the time effort you spend on these projects, FREE of charge! I agree that the vast majority are looking for cheaper/easier projects to build.

Cheers

Matt

I know front panel real estate is tough, though it can be done... this for me pushes the limits, 10 knobs, 4 push buttons

I never said that it is impossible. I have designed that kind of puzzles too, when I worked as an electronic designer. Doable but takes a lot of time.

But now we are talking about DIY project which must be easy to assemble, contain only minimum of mechanical parts and most importantly components must be cheap and easily available.

Do you remember the whining when I used (small but expensive) Sfernice potentiometers in the Neumann W492 project?

 

[strangeandbouncy]

Hi Audiox,


    you really are a superstar! That's just wonderful! Thank you so so much for this. I am certain that there will be many many happy bunnies out there.


      Awesome!



            ANdyP

 

[strangeandbouncy]

For your info,


  Canford Audio do the Neutrik trannies


  http://www.canford.co.uk/Products/23-003_NEUTRIK-NTL1-TRANSFORMER-Analogue-audio-PCB-line-input



      kindest regards,


        ANdyP

 

[[silent:arts]]

now we have to talk Gustav in doing the PCBs (incl. the OA10)
if he doesn't want to do then I will have a look in it.

Not only Canford, even Conrad, Farnell and Thomann sell the NTL1 (at very different prices)
Since I'm a new born Neutrik dealer I will ask for a quote too  8)

 

[audiox]

Here is the schematic (hosted by Google docs):
http://docs.google.com/fileview?id=0B_XBYPfmG8pVZGViZTg4YmQtMDM0Yi00M2IzLTkwYTYtOWE4Zjg2YTk0MDE3&hl=en

Components values in this schematic are for active balanced input (wire links assembled instead of transformer). Any comments welcome...

Colin promised to check the potentiometer dimensions before I publish the PCB documents.

I am certain that there will be many many happy bunnies out there.

Thanks for the kind words.

 

[strangeandbouncy]

Hi Audiox,

    many thanks for posting schematic. Just wondering about  components R24 and R25, and C27? there are no values shown.


    KIndest regards,


      ANdyP

 

[Gustav]

Got a mail from Volker about this. Im totally in if you guys are cool with having me make some boards.

Gustav

 

[kazper]

Got a mail from Volker about this. Im totally in if you guys are cool with having me make some boards.

Gustav

ummm... yes....

Things move so quickly here....

 

[strangeandbouncy]

Hi Gustav,



    Yes Please! Yessirree!!! . . . . especially with some OA10's as well . . . .


    Kindest regards,


        ANdyP

 

[2Low]

Got a mail from Volker about this. Im totally in if you guys are cool with having me make some boards.

Gustav

Great ;D

 

[Gustav]

Is there a gerber?

Gustav

 

[audiox]

Just wondering about  components R24 and R25, and C27? there are no values shown.

Those components are for transformer option only. R24 (wire link) is for grounding one side of secondary. R27 and C27 are for damping network.

 

[audiox]

Is there a gerber?

The layout is ready but someone could make a prototype first. The board is single sided so it is easy and cheap to DIY.

I am not worried about the electrical functionality but the mechanical dimensions are based on documents found on the internet. I am quite sure that the dimensions are correct but it is still better to check before manufaturing a large batch or boards.

One question before creating the Gerber files:
Which is the hole diameter that I should use for the discrete op-amps? The socket pin diameter varies from one manufacturer to another...

 

[[silent:arts]]

...
One question before creating the Gerber files:
Which is the hole diameter that I should use for the discrete op-amps? The socket pin diameter varies from one manufacturer to another...

I would suggest:
http://classicapi.com/catalog/product_info.php?cPath=71_77&products_id=122

 

[audiox]

Component layout drawings & copper layer pdf for home etchers published. See the first post in this thread.