Advice for S.E.X. with custom chassis, front and rear panels.

[Manbear]

I recently ordered (but have not received) a S.E.X 3.0. I'd like to use my own wood and mount basically everything besides the transformers and tubes on the front or rear (please reference my reddit post for explanation and pics of ideas -https://www.reddit.com/r/diytubes/comments/9eew5p/custom_bottlehead_build_and_aluminum_plate/).

I understand that this design would require a custom chassis and custom front and rear panels made of either the wood or aluminum. I also understand that building like this deviates from the original design and may complicate soldering as well as voltage measurements. I'm up for the challenge  ;D

I see that many have used Front Panel Express.  I could probably do this on my own as well with a drill press, drill, router, files, etc. or find someone near me with the proper tools.

Does anyone have advice for a starting point to help me with this design idea?

 

[Paul Birkeland]

I suppose the place to start is how much of your time you'd like to spend making something to replace what we provide you? 

Front Panel Express could indeed make you a perfectly solid, functional aluminum enclosure for your SEX amp, but I bet you'll spend $300+ to get it made.  Do also keep in mind that mistakes can be expensive.  On the positive side, you aren't going to need your own machine shop, and basic hand tools will be all that is required to put the box together.

I have done a few builds that are wood bases with metal front and back plates.  This makes for an infinitely more difficult build, and you have to be careful to be sure everything is properly grounded, but this kind of build can be done affordably with a little more time invested on your end.  Even the FPE boxes may need a little extra assistance on your end to achieve proper grounding. 

The most punishing route to take would be the drill press, files, etc.  This will take tons of your time, make a mess wherever you're doing it, and things just don't tend to line up that well when you're drilling by hand.  I have had a drill press in my workshop for ages now, but I use the guy with the waterjet that's 10 minutes away from me instead.  The mess stays there, the cuts are perfect, and the material is in stock 10 feet from his machine. 

 

[Manbear]

Once again, thank you for your very helpful responses!

This makes for an infinitely more difficult build, and you have to be careful to be sure everything is properly grounded, but this kind of build can be done affordably with a little more time invested on your end.  Even the FPE boxes may need a little extra assistance on your end to achieve proper grounding.

Yeah, part of me hates to create an unnecessarily challenging and potentially catastrophic build. If front and rear plates are metal (sides in wood), what specifically would create a grounding problem? I can see how the ground wires would either have to make a long run over to the ground lug or the aluminum top and front/rear plates would need to be in constant, clean contact either directly or by wire, correct? This may be oversimplifying.

The most punishing route to take would be the drill press, files, etc.  This will take tons of your time, make a mess wherever you're doing it, and things just don't tend to line up that well when you're drilling by hand.  I have had a drill press in my workshop for ages now, but I use the guy with the waterjet that's 10 minutes away from me instead.  The mess stays there, the cuts are perfect, and the material is in stock 10 feet from his machine.

Fortunately, I don't mind spending a lot of extra time with this build in order to do it correctly, but I'm not looking for torture. I do have access to a water jet! I will explore how feasible this option is this week. I really would like to configure the S.E.X in this way, however I can't seem to find many examples of this design. Thanks again.

 

[Doc B]

DIY sometimes means Design It Yourself. This is a kit that we feel has been pretty well evolved over about 23 years. I'm not saying you shouldn't redesign it to your heart's content. I'm just saying that we are pretty sure the way we have laid it out has pretty solid reasoning based upon a lot of experience, and that asking us to help you do it a way we have not done it is kind of asking for reassurance that you can really only give yourself by trying it and learning from the experience. You really need to go at something like this with a healthy dose of self confidence.

We are happy to offer technical support for the product we deliver, and talk about why we did it the way we did. But there is a difference between tech support and design consultation. Luckily there is a ton of info on the interwebs about grounding and layout.

 

[Manbear]

Thank you for the honest response. I never intended to ask the designers to change a properly working design just for me. I guess I figured that these forums would, however, be the best and most direct resource to get help from others who may have more experience with exactly what I envision.  I get what you’re saying. I may or may not give it a whirl and hopefully will not electrocute myself. I like to learn principles first but will do it elsewhere.  I do appreciate all of the dedictation that you’ve put toward your products. They’ve already have and will continue to provide me with a lot of happiness! 

 

[Paul Birkeland]

the aluminum top and front/rear plates would need to be in constant, clean contact either directly or by wire, correct

They really have to be wired together.  You'd be amazed at how noisy an amp can get from a front panel that is touching the top plate but not making solid contact.

 

[Paul Birkeland]

I guess I figured that these forums would, however, be the best and most direct resource to get help from others who may have more experience with exactly what I envision. 

I can tell you that I did a BeePre with a full custom aluminum enclosure and some other fanciness.  I started the design/build before the BeePre came out, and I finally ironed out all the kinks late last year.  That's just over 5 years...  (some people even say I know what I'm doing too!)

 

[Manbear]

I wish that I could plug into your brain and download all off the technical info! I would LOVE to be able to do the same, however it seems that it may be a bit overly ambitious to start messing with things too much. My Type A personality tells me to make something truly unique. I do have a very sexy (pun intended) piece of exotic wood that I will use, so may just start there. I'll post up some pics when I'm done. Thanks for the help.