Doug Self Preamp from Linear Audio #5

[Hicoco]

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

[fvzeppelin]

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


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


Ideas anyone?

[tER299]

Originally Posted by Hicoco

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?

[Hicoco]

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.

[Hicoco]

Originally Posted by tER299

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.

[Rick G]

Is this V2 available on your site for purchase?
Also, do you have a template avail as a drilling setup for this i/o board?

Rick

[Hicoco]

Not yet, i have to send the file for production to the board house, and yes i have the drilling template for the rear panel.

[Rick G]

OK.Thank You.Am interested when available.

Rick

[diyralf]

Without being negative: I miss the RFI filters on the board.

[Carl_Huff]

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?