Doug Self Preamp from Linear Audio #5

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Slimline 1U right here from the DIY store. Will have to ship off front and back panels to FPD for machine work.

I believe the DIYAudio store can do the panel customizations using the FPD files. No need to engage a separate vendor. In addition, the DIYAudio store offers re-anodization after milling, which FPE here in the USA does not offer.
 
Finally about to start this! Couple questions-



1) Digikey is out of the Amgis L01-6354 until December. Alternatives? Antek AN-0218 - 25VA?


2) Input - I only need one input (RCA for phono). Could I remove the IO and wire directly to the main PCB? That seems to leave out the 3 second delay on the IO board. Not a big deal to leave the IO board in.



3)Another idea is to include a phono (Bugle2) in the case and run it directly to the main PCB. I will primarily be using this with an Aleph J, so it would be nice to have phono-preamp-amp connection with the ability to bypass the tone controls. Might be unnecessarily restrictive, but I can always change it later.


Please feel free to PM me on questions 2&3 since they are specific to my build and I don't want to clutter up the thread. Any general insight or considerations would be extremely helpful. Still learning on this.
 
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I did not know that the store did machining and Infill. They use .FPD's. Are they just sending on to Front Panel. How about costs?

Yep - its in the Chassis section under Customization Services. Prices are listed there. It's competitive with FPE, if not better. I believe they do the work themselves. The FPD files are a form of CAD files as far as I know, so they can use these.
 
Finally about to start this! Couple questions-



1) Digikey is out of the Amgis L01-6354 until December. Alternatives? Antek AN-0218 - 25VA?


2) Input - I only need one input (RCA for phono). Could I remove the IO and wire directly to the main PCB? That seems to leave out the 3 second delay on the IO board. Not a big deal to leave the IO board in.



3)Another idea is to include a phono (Bugle2) in the case and run it directly to the main PCB. I will primarily be using this with an Aleph J, so it would be nice to have phono-preamp-amp connection with the ability to bypass the tone controls. Might be unnecessarily restrictive, but I can always change it later.


Please feel free to PM me on questions 2&3 since they are specific to my build and I don't want to clutter up the thread. Any general insight or considerations would be extremely helpful. Still learning on this.
Talema 70054K

You can wire the phonostage directly to it
 
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Need help debugging

I am currently setting up my 2nd DS preamp. Unfortunately, I am facing a strange problem and I don't know where to start debugging:

Basically, everythng works fine, including the controls :) But when I turn up the Lo Gain, starting from somewhere above the center position, there is suddenly a loud hum on both channels until I turn back the Lo Gain :eek:


(Think I even crashed my 2 test speakers with it :ill:)


Ideas anyone?
 
tER i have I/O board with phono input, look in my signature. i don't know if that can help

Thanks for the tip, it may very well! Do you, by any chance, have any FPD/DXF-files that'll fit the I/O board? And how would I go about connecting the I/O-part to the board? It's rather hard to tell from the images, but does the board switch between possible in puts (just like it would in the Doug Self I/O - output, see attachment) or are the RCA and XLR always active at the same time?
 

Attachments

  • IO.jpg
    IO.jpg
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tER,
The board that will fit the best your need is 8 inputs with 4 RCA and 4 XLR ( separate from each other) with input RCA1 is reserved for phono input, the inputs switch between with the selector.
Yes i have FPD/DXF-files.
The inputs and ouputs connection to Dself preamp could be done easly from the HDR VERT DOUBLE 20P to the I/O board with the 5-pin Molex KK
The bad news is i am out of stock actualy of this board, i will need 2 weeks to get those, please PM if interested.
 

Attachments

  • PCB I_O PREAMP 8 INPUT connector version XLR:RCA.pdf
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  • PCB I_O PREAMP 8 INPUT connector version XLR:RCA.jpg
    PCB I_O PREAMP 8 INPUT connector version XLR:RCA.jpg
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Joined 2018
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Thanks for the tip, it may very well! Do you, by any chance, have any FPD/DXF-files that'll fit the I/O board? And how would I go about connecting the I/O-part to the board? It's rather hard to tell from the images, but does the board switch between possible in puts (just like it would in the Doug Self I/O - output, see attachment) or are the RCA and XLR always active at the same time?


I updated and redesigned the 8 input Board (340mm x 66mm)to be able to use the same ribbon Cable who is connected to the Dself Preamp board with a new 20p connector. That is 4 Unbalanced RCA and 4 Balanced XLR separate Input.
 

Attachments

  • PCB- I-O CONNECTION BOARD 8 INPUT Version 2-XLR RCA.pdf
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  • PCB- I-O CONNECTION BOARD 8 INPUT Version 2-XLR RCA.jpg
    PCB- I-O CONNECTION BOARD 8 INPUT Version 2-XLR RCA.jpg
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Hello all,

Watching this thread I wonder if builders would be interested in a nice graphic display showing input and what device has been assigned to that input? What I am envisioning could be a simple module that the existing IO PCB would simply plug into. The IO would be switched by the new module.

If the answer is ‘yes’, there is an interest, I then must ask the question should it be a simple $3 chip driving a graphic module or do we go all out and use a BBB (Beagle Bone Black) computer and explore the world of USB DACs and music servers. We could do an internet lookup and display a graphic and details of the music playing. Using a BBB would open new doors for us to experiment in.

Please keep in mind I only toying with the beginnings. So is there interest? If the answer is “yes” what direction would you prefer? A simple display or an all out embedded audio appliance?