Choke specs for the Crack

[trollchu]

I'd more love to see to see how someone'd plan to fit it all that in a Crack build, a dual mono power supply with three chokes sounds like a job for a master craftsman.

I have a couple more questions. I'm still in the midst of painting my Crack and the paint I'm using needs three weeks minimum drying time for best results, so I've got a lot of time to plan the mods I'd like to implement in my build. I'm planning to go with two Hammond 158M chokes on 1.5 inch spacers so that they still fit within the wood base and I'd like to mount them above power supply caps one and two. When it comes to mounting chokes, is there a way to insure that my placement of them won't cause inference with the PT-10, and can I test for that somehow?

These other questions are a bit off-topic for this thread, but for the third power supply cap, as well as both sides of the output caps, I'd like to run 100uf Wima's and I'm considering using four Wima's in parallel in place of the third power supply cap and two Wima's per side on the output. Would I run into any issues in running paralleled caps in any of these positions?

Lastly, what benefits are there to be found in bypassing power supply caps and what are some good options for a stepped attenuator in 2025?

 

[Paul Birkeland]

There isn't much concern about a power supply choke and a power transformer interfering with each other.  All those Wimas will take up a lot of space, that's the only issue I can think of.  Bypassing caps was pretty popular around 1995-2005, but power supply caps have improved, and the technical merits of adding bypass caps have become dubious at best.

 

[trollchu]

That's all quite reassuring to hear. If so, I think I've mapped out all my mods then, minus the pot.

The 100uf Wima's are cool cause they're still significantly smaller than a lot of other film caps, and for the third position, four of them side by side only take up 4.88 inches. They are the automotive grade Wima's, which are still polypropylene film and low ESR; they're also cheaper than 100uf Audyn caps right now. What I'm planning to do for those is to mount them to a sawed off piece of a clipboard and mount them on standoffs just like the chokes,  but I still need to check and confirm the height of the Wima's versus the height of the Crack, I want it all to fit under the wood chassis if possible.

It's a crimson red Crack build, with all the Wima's it'll be red inside, too. Thanks again, Paul.

 

[Steakface]

The Triad C-7X has a maximum current rating of 90mA, whereas I've measured the current in the power supply after C1 as ~80mA. This raises some red flags when inductor saturation comes into play as typically I would expect some extra leeway for variances when it comes to the maximum allowable current. In this situation we have an ~11% difference between the maximum value and the measured value which may cause the inductor to begin saturating

Triad states in the documentation on the C-7X:
"Smoothing chokes are power supply filter chokes having a core with an air gap which prevents saturation at maximum current"
I'm interpreting this as saturation is something that we don't need to worry about for this inductor unless we exceed 90mA, but the engineer in me urges to double check.

I don't have a scope to check nor do I have the know-how to measure inductor saturation (yet). For those with experience on the matter, what are your thoughts?