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jessie.dazzle wrote:

As a way of forcing myself to see the thing as a whole, I will start by converting this schematic to a 3D CAD model, illustrating each component and its relation to the others (with more distance between the parts than in photos of the completed amps) so that I can really see it, turn it all around in space, zoom in and tour the site like goldfish. The more experienced may laugh, but this exercise will help me get familiar with the composition… something like the act of writing. This is exactly the appraoch I use whenever I set out to rob a bank... its what they call "casing the joint". Once I create the data, if I feel it really is a help, I will make it (or at least high res static images of it) available to anyone interested.

I thought it would be worth if I pass some comments about out Milq layout. Whatever methods you use: 3D CAD model of getting the actual parts and moving them around there are some basics that you should take under consideration. I will pass the rules that I used, feel free disregard them, to employ them or alter them.

Let look at the Milq circuit:

http://www.goodsoundclub.com/PDF/Melquiades_SET.pdf

First thing first you have to decide what version of Milq you intend to build. There are two major layout-affecting versions available: using input choke filter and using input capacitors. The Milq second stage must be input choke filter – this is not negotiable, but driver stage and bias supplies might be input capacitors. The benefits of input capacitors is that entire PS become more compact, and we are talking about 3 power supplies. With CRC you have no hot running bleeder resistor, no chokes and lower voltage transformers – it all will make the Milq simper. I would like to avoid in this post arguments about input choke vs. input capacitor – I juts would say that input choke has own benefits as well. It would be worth however to note that I have built Milq with input choke and with input capacitors supply and I would not say that there was a whole a lot of sonic differences. Once again, in the outs stage to use the input choke is a must. So, if you go for input capacitors then you have only few large parts: 3 power transformers, output transformer, C2, C10… and it’s it, the Milq is really simple circuit to build from there…

I would also suggest that for sake of simplification and space saving it is perfectly possible to drive the positive gas tube form the power supply of the driver stage, droving voltage on a resistor. I did it and it does sound perfectly fine.

Some other things that you should under consideration I the Milq layout:

1. Prototype-position your parts, as they will be positioned, and determine the shape and location of your main ground terminal. This is important. I usually make my circuit’s main ground with 3 cross-wired 8ga copper stranded cables, then bend it in the shape I need and then fill it with solder. All the rest companies are just portioned with this “minus” around the main ground terminal.
2. Keep R2 as close as possible to the pate of the driver tube. Actually solder the resistor leg right at the tube socket.
3. R5 and R6 should also have this legs sitting right on the tube socket
4. Keep R4 right at the left side of R5
5. Keep the returns legs from C4 and C5 right at the socket of V1 and V2
6. If your negative supply is not too far from your out stage then c12 is unsavory.
7. Run a fat “ground” cable form the cathode of the driver stage to the chasses in the very single point: the negative terminal of you RCA into jack.
8. Position C10 as close to the OPT as possible.
9. Position OPT as close to the tube plate as possible.
10. R20 should go directly to the V4 grid.
11. C3 should bridge the stage and be very short but beware the heat dissipated by 6C33C. You might position the cap relatively close to the 6C33C but it will depend from the air-flow in your amp, elevation of the components and so on.
12. Be carefully with positioning anything within 3” from 6C33C – it will be running hot. Use high temperature melting solder to solder the 6C33C’s filaments.
13. Try to use the native element’s leads wherever is possible. The shorter pass is better.
14. All AC runs should be crossed-wired. Use crossed-wired with DC feeds if it is applicable.

It would be pretty much it, at least t is all that it atop of my mind at this moment.

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