Doug Self Preamp from Linear Audio #5

Tone control : when the pots are set to get a flat response, there was no significant level difference(about 0.01 dB or less) when on or off.

Here are the diagrams. Level full scale at +/- 1 dB

07. level with tone control flat, off and on, right channel
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨
tone control, off -> red
tone control, on -> green

08. level with tone control flat, off and on, left channel
¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨
tone control, off -> red
tone control, on -> green


 

Attachments

  • pre_Self 07 tonectrl on off R.png
    pre_Self 07 tonectrl on off R.png
    51.1 KB · Views: 904
  • pre_Self 08 tonectrl on off L.png
    pre_Self 08 tonectrl on off L.png
    22.6 KB · Views: 897
Front panel

Well, if anyone is still following this thread, I finally finished my front panel. Not perfect, but not too bad.
It was all done with a single transfer from CraftyComputerPaper at Frequently Asked Questions
Alignments are not perfect but we shall see. It is easy to remove and repeat. One small issue is that the transfer material can stretch slightly and this can make alignment a little tricky...that's my excuse anyway:)
 

Attachments

  • P1020331.JPG
    P1020331.JPG
    320.8 KB · Views: 871
Transfer paper

George,
I am still working on my case as well. i am going to try this product on my Wood case.
Waterslide Decal Paper, Image, Transfer Paper, Iron On, Decals
failing that i will try what you used. :)

Rick

Hi Rick,

Let me know how that goes.
The only problem with the method I used is that the edge of the transparent film is just visible to the left and right of the panel. That was why I used one large decal..fewer edges to worry about. The best solution would be something that transferred just the text and used no film. Still, with a couple of sprays of clear varnish the edges are nearly invisible
 
I have a 3d printer and will be making a front and back panel, albeit plastic (abs). So let me ask has anyone made a cad file of the front and back, or is there a pdf drawing showing the the dimensions including the screw centers etc., if so I can draw it up in Autocad and then print the panels using an stl file.
my printer is limited in size to 9" x 6" so the panels will have to be in two pieces and spliced together and include matching knobs, but my days of drilling out aluminum are done.
 
Panels

These 2 are what i used.
I didn't use the Power switch hole.
The Rear Panel Large holes are 22mm (7/8") works fine. The RCA jacks are 10mm, i used a 10mm drill bit & a reamer to make em just a tad larger.
Hope this Helps.

Rick
 

Attachments

  • Backpanel_May13.pdf
    35.8 KB · Views: 163
  • Frontpanel_May12.pdf
    45.3 KB · Views: 139
Panels and BOMs

Here's the current status of my DSelf Pre-amp project.
image3_zpsni7v0yvl.jpg

image1_zpsuz6khk0w.jpg

image2_zpsy2lrr2t5.jpg


Most recent BOMs and panel templates (in SVG and PDF formats) here:
https://drive.google.com/drive/folders/0B_svLQu7hxPtTUcxZ1hma2RwR0k

(The enclosure is a repurposed case from a piece of hospital gear(?) I got from an electronics recycler. The panels were cut by a local guy with a CNC router. I had to rebore the holes on the front panel because they were a bit small, but I think that was a problem with the cutting, not the PDF template. Sorry if this isn't the proper way to share photos.)
 
Last edited:
Thanks, Rick! This is the first time I've actually spent time figuring out an enclosure for a project. (Most of my past DIY efforts have included a easy-to-configure recommended enclosure.)

A quick question for you pros. I plan to run a 120V AC line from the IEC on the back of the enclosure to the switch on the front, then to the power supply. Is that acceptable practice? If so, should I twist the two (up and back) 120V wires together and run them along the side of the interior of the enclosure?

TIA.