Reducing Ambika PCB size using surface-mount components


This is my first post here.
Recently, I have recently considered having the mobo and voice cards for the Ambika printed, but have held off due to the size of the boards and resulting cost of doing so.

Considering that the board components are all in through-hole packages, the outer dimensions of the boards could be reduced substantially by redesigning the boards to use surface-mounted components and connecting the audio jacks, pots, LCD, etc. to the board with connectors, albeit at the cost of increased assembly difficulty for some individuals.

Do you feel that this is a worthwhile undertaking? Has anyone had previous experiences doing what I’ve described above? I performed a cursory search of the forum for related threads, but was unable to find anything. Please forgive me if this topic has been discussed here before. Also, I wasn’t quite sure of the best forum category for this thread. Mods, please move this thread to where you feel it is best suited.


Why don’t you just buy the boards in the shop? You would support the designer of this magnificent machine by doing so.
SMD isn’t really made to be soldered by humans. And the size of an Ambika isn’t really that big so there is not so much gain in making it smaller.

Although I agree that buying from the MI shop would support the designer, I am intrigued as to what size would the final Ambika have if it goes the SMD route and what price difference would there be as pertains to the smaller boards vs. the standard mobo

I have considered doing something like that, but never really got around to it, the cost of prototyping it would be large, and the market would be tiny, since you can’t assemble it yourself…And while you strictly speaking could sell it as a product you made, you would still have to give credit, and you would probably earn a lot of hate if you somehow tried to bypass this.

The people on here are mostly DIYers, and I doubt many of us have the required tools for serious SMD work, so what is the point?

well but some have the tools for through hole soldering, which is good enough for 1206 or 0805. but there’s no point in making it smaller just for the size, as it’s already in a good ergonomic state imo. when you try to fit it in 3U eurorack (for whatever reason) you still have the 2x 40 LCD display which won’t be smaller in smt. also the pots need reasonable distances and are ideally positioned in certain spots (the way they are). also i like the switches, wouldn’t like to swap them with some tiny mini tacts midibox style.
but i can see a reason that would be worth doing it, that is to fit it in 1U 19" rack, controller on the same board as the core, with voicecards mounted flat behind so that you’d have a really REALLY flat ambika.

FWIW, there is an ongoing discussion at Muff’s here

Plenty of folks do 1206 and apparently 0805 size SMD by hand. Also, it seems the majority of posts in the SMD discussions I have read by folks who have actually tried SMD like it, claim it is significantly faster than through hole, and it’s quite often much cheaper. I have no experience with it yet but I am building a drum module soon which uses a few dozen 1206 size parts and I’ll be using the same conical tip on my Weller iron and .020 or .031 solder, just like I do for through hole. There are plenty of tips around for doing the larger SMD packages with no special tools.

I’m fairly certain that by the time you consider the price for a small quantity of boards that it wouldn’t be any cheaper than ordering the standard Ambika boards, but I’m not here to discourage anyone from tackling unique and challenging projects if you’ve ‘got an axe to grind’, as they say :stuck_out_tongue:

And, you could still certainly use all SMD parts and then do the pots, encoder, and jacks as through hole to keep everything board mounted.

I suppose that even with the most possible condensing that you’re still going to have a box which is something like 70% the size of the regular Ambika, though…gotta fit that LCD, knobs, and switches in there anyway.

If you do the Ambika as a VSTi or AU you can shrink its size to nearly 0

So to nail it down: WHY? Its size is limited by the UI Parts, while you might save 2-3 cm in depth and maybe a bit in height, would it be worth the hassle redoing all the PCBs and solder this Fliegenschiss™ sized parts by hand? If you make it significant smaller you might render it useless due to the fact nobody can tweak the knobs comfortably. You wouldnt want to shrink a MiniMoog, dont you?

I never needed a very logical reason for most of my hobby stuff, hence I am truly interested in seeing just how much smaller would and actual SMD Ambika shrink.

I do love my thru-hole Ambika, I am just very curious.

Plus, I do see the point of going SMD for new Instruments that might take advantage of newer/more powerful components only available with SMD?
I am sure that more experienced people than me would go a very long way in creating new stuff that need SMD?
I have read multiple times that some design constraint has been unavailablity of some component in thru-hole, so I guess that SMD would “liberate” design more?

This is something I looked into many times in the past. I think I’ve routed 4 or 5 different generations of this :smiley: - everything from a 1:1 “port” of the existing design, to a totally new design – with, in-between, something bastard that could still be used with the through-hole mobos. I never found a way in which it would make sense from a business point of view.

In terms of size, one can fit two voicecards in the same space as one of the existing voicecard. The result is that the assembly can be made much slimmer - the limiting element in terms of height becoming the MIDI connectors. Width and depth do not change much. You can make things smaller by compromising on the UI - not sure if it would be a good thing. Here come questions of business model. If you have this made cheaply, it is in your interest to keep the UI slim to have a $1000 box that can rival with a Tetra, with six voices and no curtis chips. If you want things to be made with love and quality, it is in your interest to expand and add a lot of UI so you can have a $2500 machine, because nobody would pay $2000 for something with just 8 knobs.

Anyway… SMT Ambika is silly because almost everything in this project is designed under the through-hole, DIY kit constraint. Like, if I had to do a polysynth with SMT parts, I couldn’t think of a worse choice of architecture than 7 AVRs at 20MHz hooked on a SPI bus :slight_smile: All the work I did on the Shruthi & Ambika is worthless outside of the “through-hole DIY kit” context - that’s why you’ve never seen and will never see a pre-assembled Shruthi or Ambika.

1206 SMT is not hard to solder and indeed fun; but it’s a PITA (gyros) to prepare kits for it. 20-30% made a mess of the TQFP chip on the MIDIpal. Asking people to bootstrap their chips is another PITA. Building a rig to bootstrap TQFP or smaller chips before packing them in the kits is doable, but yucky…