Ambika...or Juno-106?

So, I finished an Ambika with 6 SMR Voicecards for someone and I’ve had the past week waiting for payment to play around with it. I had never heard the SMR VC but I was looking at the schematic and seeing if yewtreemagic’s “ir3109 squelch” mod could be done to them. Well, once they were built I was absolutely surprised at how closely it sounds to a Juno! Other than the oscillators sounding different between the two, the filter is spot on! (oh, and the Ambika envelopes react differently than the Juno)

As I have a Juno-106, I threw together a couple demos: Video Audio

The audio clip is a side by side comparison with the Juno-106. Of course Soundcloud mucked it up with their compression. Ohwells.

Anyway, proof once again that there is no filterymagicsauce™ in the IR3109.

Need to check this video later I just purchased a 106 and want to make an Ambika on the summer vacation…

Hi qp: they do sound close!

However, can you clarify - is the Ambika using stock SMR cards, or did you in fact add my ‘IR3109 squelch’ mod to them?


@yewtreemagic. They are the stock SMR cards. No need for the mod!

There you go then - all my ‘IR3109’ mod does is drop the internal signal levels to give them more headroom.

I suspect Olivier may have already dropped the levels on the Ambika SMR - let me take a peep…

Actually it looks at first glance as if the 1st amp in the SMR4 MkII with gain 33/100= 0.33 is missed out completely in the Ambika SMR, which suggests that the internal signal levels are much higher - perhaps I’ve missed something obvious :wink:


There are two things you forgot to take into account:

  • The DAC has a 4.096V dynamic range rather than 5V.
  • The whole thing runs on +/- 8V on Ambika.

So it runs at a higher level, but not much higher…

Also the behaviour of the whole thing is different because the Ambika voicecard uses C->buffers instead of op-amp integrators.

Guys, I decided I don’t really need an Ambika. You’re really not helping here…

@thijs… you don’t know what your missing :wink:

@thijs just because it can sound like a Juno-106 it’s a very different kind of beast. I won’t ever let my Ambika go. In fact, I may have to get another one :slight_smile:

I know it can do a lot more; it’s just that any talk of it seems to take me a little closer to actually building one. :slight_smile:


The vicious part is that, with the choice of filter boards, when you decide to have an Ambika, the door is already half opened to having a second one.

The idea was to show how it can sound like a “vintage” synth as well as a modern, highly patchable beast that it is. The depth of this thing is insane!

i appreciate this post qp.

i’ve checked a lot of your ambika demos on SC and i wondered why you didn’t offer them as downloads?




@pichnettes: thanks for the clarification - slightly lower signal levels from the DAC in conjunction with higher voltage rails should give very similar improvements in headroom.


@0e0, it’s not intentional. Just never think about it. I’ll offer them as dl’s.

One issue with the 106 is that it is big and heavy. Also it will of course be quite old so things like pots and sliders may be quite worn out.

@Dunk: And the voice cards. I’ve already replaced 3 voices in a friend’s 106.

you can fix the broken voice cards by using acetone to take off the resin.

I think the chips actually fail after a while which is more of a problem. I looked up the weight and it’s 10kg (22lbs), that is quite a big beast. Cool to install into your studio but not cool if you want to take it round for a jam at someones house.