Yes, the wirepads in the component list correspond to identifiers in the schematic.
I thought XL-JMP and XR-JMP would be jumpers (and maybe they are on the PCB) but they are the crossfeed-to-gain-stage connections to RIN and LIN at the far left of the schematic, if I'm understanding the configuration correctly. It looks like only a dozen or so of the wirepads are for the panel-mounted components, namely the switches for the crossfeed circuit and the DC (with 12V regulators DCin needs to be 30-35 volts) power jack. There is no power switch or volume control. I don't know what GBY and GLEV are other than CAD placeholders.
I thought XL-JMP and XR-JMP would be jumpers (and maybe they are on the PCB) but they are the crossfeed-to-gain-stage connections to RIN and LIN at the far left of the schematic, if I'm understanding the configuration correctly. It looks like only a dozen or so of the wirepads are for the panel-mounted components, namely the switches for the crossfeed circuit and the DC (with 12V regulators DCin needs to be 30-35 volts) power jack. There is no power switch or volume control. I don't know what GBY and GLEV are other than CAD placeholders.
You are correct! Oh, GBY and GLEV were there in case one needed to ground the bypass or level switches (in case of hum pickup), and they weren't using the case for a ground. All of the different connections are explained better in the ExpressPCB schematic, I haven't added them to the Eagle schematic yet. I'll see if I can get time to do that.
I wanted this board to be flexible, which is why there are so many options as to what needs to be stuffed and which holes lead to jumpers or to actual components. Sorry for all the confusion.
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Not necessary to apologize. Thanks for clarifying. You ought to consider eventually fleshing this worthwhile project out a little with a proper component list, parts substitutions, enhanced option descriptions, pics, and that sort of thing. I have several hpa's but none with a crossfeed. I may give this a go myself.
Thanks for the encouragment. I will get a parts list up soon, I haven't actually built this board yet though. One of you may beat me to it.
BOM
This should be a basic parts listing, of the entire board stuffed (with exception of the TLE). Broke the BOM down into Power supply, amplifier, and crossfeed sections.
Will still need to acquire ~30VDC power supply, and an enclosure. Was intending for this to be on a bench, not really portable. You could make it more portable with switch/power selection.
This is an Excel file, but will open with Open Office also.
This should be a basic parts listing, of the entire board stuffed (with exception of the TLE). Broke the BOM down into Power supply, amplifier, and crossfeed sections.
Will still need to acquire ~30VDC power supply, and an enclosure. Was intending for this to be on a bench, not really portable. You could make it more portable with switch/power selection.
This is an Excel file, but will open with Open Office also.
Ideas for different ways to load the board, with graphics! Any part in black is needed for that particular configuration.
Attachments
The ExpressPCB board actually already has MGND tied to both grounds with a thermal pad on the top and bottom of the board. So, if you order from ExpressPCB, there is nothing else to do here, it Just Works (TM) as I intended.
MGND in this instance is just a place where the two ground planes come together, and since we're using a virtual ground, it just makes sure all ground potentials are equal.
The only exceptions are if you use the TLE instead of the discrete rail splitter design. In that case, you would tie MGND to TLE OPT (between the power supply caps). If you're using a split supply off-board, then solder your ground wire to MGND.
MGND didn't become a pain until I moved to Eagle.
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