First of all, Thank you Angelo for your order! I'm looking forward to some samples to share with other folks here in the new year!
Secondly, Angelo was kind enough to allow me to copy/paste some of the discussion we've had via PM. He asked a lot of good questions (I'm not sure if my answers were good enough, but it may be of some benefit to folks!).
... I'd like to know, what source would you use it with: You say it's very clean sounding, but I'm not sure how and when this could be a good thing (I am more used to "colored" stuff, such as API...). I need to know if these boards could actually be what I'm looking for.
Everyone has opinions on what sounds good. I like Clean Pre's because I can then color the sound after I've recorded it. I can add EQ, Compression and other effects, or even run the signal into another pre later on. Clean Pre's give me options AFTER the artist has left! . The whole concept behind the Eden Pre was to get "Wire with Gain". The plots in the users guide show flat distortion by frequency, along with very low distortion levels even at high gains.
Keiths' (SSLTech - Mr Analog at Expat Audio) first thoughts for material to record with this pre is anything Acoustic, Orchestral or Choral. Anything where you want to capture much more detail, and add much more gain is where Eden will excel. Think of recording an acoustic guitar, where you want to capture the room, as well as the detail in the guitar players technique. Eden is going to do it fabulously.
Keith is building a 4-pack of Eden's into a 1U case. He will be recording a choir in Florida with it soon. Those samples will be available in the next few weeks I hope.
But I have a question about your front switches: I saw they are digitally controlled, would this somehow affect the analog audio path? ...just to be sure I won't have any digital glitches or pops
The digital section can run from its own supply if you like. It never touches the analog. All it does is switch relays. I used a separate 12v power supply (from a dollar store!) and put it inside the case.
would your Uber PSU supply enough power for 4 Edens?
As for the drive capability of the uber supply. 4x Edens will be easy.
The ina163's each require 10mA, The drv135's require 5mA each. led's are are a total of 15mA and the opa134 is another 5mA... Giving a total of 45mA.
just to be sure, when you say "I used a 12v power block" you mean I'll need extra 12v to feed the switches? - or you just mean that those 12v for the relays come from the digital supply? sorry, I did not understood this passage
You'll need OMRON G6K-2P-XXX relays for the front end switching. They come in a variety of voltages.
On mine, I used G6K-2P-DC12. They require 12V on them to switch.
The Digital Control Board uses a regulator to take any voltage above 3.3V (up to about 24V?) down to 3.3V. That 3V3 is used to power the micro controller and the LED's for the switches.
The Digitally Controll Mic Pre Front-End has transistors on it that take the 3V3 from the microcontroller board, and switch the 12V to the relays.
Alternatively, you could use 5V relays (G6K-2P-DC5). That would allow you to use a small 5V supply for the digital section.
That would be VERY nice. Then you could use a small cell phone charger (think how small an Iphone charger is!).
You could put a small cell phone charger inside your rack case, that will be shared with the primaries of your toroidal transformer. (same ground).
The DC5 relays require 21mA to activate. you have 12 of them in a rack. Thats ~250mA. That's about half of what a low cost 5V cell phone charger can supply.
So --- In Summary. I suggest either a 5V or 12V power supply to supply the digital switching boards and relays. The selection is based on which G6K-2P Relays you select.
Thanks again Angelo - Really appreciate the feedback, the questions and your order!