NorthernLightX

Het zijn losse onderdelen, als er in principe geen extra geld gevraagd wordt voor de software in de PICs MAG het juridisch gezien volgens mij wel. Of het netjes is zonder TK eerst te vragen is iets anders... Vind het wel een boel geld trouwens, of ik moet dingen over het hoofd zien...

Hi, if CV can be used instead of digipots: fits me fine. I already have a couple of MAX525 lying around, And it's more universal than digipots too. Now all you need to think up is an easy to use way of converting CV to resistance... Another option: use both! A single core is able to support an AOUT board and digipots. Use the pots where 8 bits is enough, use aout where you need 12. In general, 12 bit is used for filtersweeps and stuff, and those filters are already CV controllable most of the time. 8 bits is 16 times the resolution of 4 bits (the second channel of AOUT_LC) and that should be more than enough for everything not filter related in my opinion. In that case the stuff to develop is still a digipot board (sorry to be so stubborn. ;) ) as the CV outs are already in place on the AOUT. What might be interesting is a new S&H board, with IC's that aren't so hard to come by. Cheers, Alex.

I'm pretty confident that I will get a quiet digipot solution. As I am really only interested in MIDIfying new circuitry (as opposed to modding existing stompboxes) desoldering pots is not an issue for me. I will work with SIL headers and female SIL connectors, so as soon as a circuit works with standard analog pots, I can swap the pots for the digital ones, and test away. AOUT_LC is also an option. I wonder if 12bit isn't something of a requirement, as TK does also design this board to have a 12bit (and a 4 bit) DAC. Vactrols need to be shielded from light, or they will behave differently during dy and night. Also, when including more than one vactrol in a circuit, optical isolation is a big issue because else the LED from vactrol 1 could affect the LDR from vactrol 2, right? I believe implementing vactrols instead of pots is very, VERY tricky. I was surprised by Hastings' audio sample, I couldn't hear any artifacts at all while he was sweeping the settings. After this audioclip, I became confident digipots are the answer. Moreover because they can be interfaced via SPI, no need for additional (expensive) hardware like DACs. The Analog Sollutions IC also used by Hastings is in effect 4 potmeters in one. Surely for new designs, the costs for 4 analog potmeters would be the same or more. While my current design plan is aimed at providing digitally controlled distortion for the 4xMBSID, I have also played with that idea. I believe that digipots via SPI is by far the cheapest sollution for FX gear that is not yet equipped with CV inputs. My setup for a MBFX unit would be like a modular synth, but with no knobs and buttons on the outside of the "modules". A Core equipped with a digipot board and an AOUT should be sufficient for controlling everything you can dream of. A panel with some rotary encoders can be optional, if no other midibox provides this functionality externally already. Example: I'm not planning on making a MB64e myself, but if you already own one it would be perfectly suitable to control stuff. I would opt for a less extended control surface. But LEDrings/bars and stuff like that could be part of the module frontpanels, very good oversight what gets tweaked at what time. A patchbay is not something I would make, I'd just add the input and output jacks on the front of every module. That way you can patch any way you like, and it's always clear what you're attaching where. No, I think MBFX is more like a firmware to interface with FX modules, not a MBHP module by itself. The digipot or vactrol circuits could become modules in the "MBHP program" if they work good. That's also the path I'm going to take: a separate board with the IC's to interface with the analog gear. Only some cables run from the FX circuit pot connectors to the interface board connectors, to keep digital noise and stuff far away. Don't know, I think not. But sorry: don't care too much either. AOUT_LC is available to reduce cost, AOUT classic to provide all options. Cheers, Alex.

De Reichelt order loopt inmiddels, de deelnemers zijn als het goed is op de hoogte van alle voortgang. Maar eigenlijk post ik omdat ik even iets kwijt wil over de nieuwe bordjes van Smash: ze zijn uiteraard heel mooi en goed, maar nu die nieuwe ontwikkelingen eraan zitten te komen met die PIC16F88 als docherbord enzo, wil ikzelf toch heel even wachten wat daarmee allemaal gebeurt. Ik heb nog voldoende knutselspul in huis (zeker als die Reichelt order binnen is) om me een maand of 2 a 3 zoet te houden, dus ik bestel zelf niet binnenkort bij Smash. Als er mensen zijn die wel graag snel iets van Smash zouden willen hebben, maar geen creditcard hebben of op de verzendkosten willen bezuinigen, dan bied ik alsnog aan om de bestelling op mij te nemen. (houd er rekening mee dat als je het door mij vervolgens binnen NL wilt laten verzenden dat ook geld kost, aan postzegels en verpakking). Gr, Alex.

You need to attach them yourself. Easy, if you can keep the cable straight. The connectors work with "vampire" teeth, no need even to strip wire-ends. Look at the LCD-cable PDF in the LCD module section on uCApps, very detailed description with pics there (not exactly the same, but similar enough). Cheers, Alex.

Nevermind Smash, almost everyone uses panel mount connectors anyway, or don't they?

Designing your own stuff could become quite hard like that. I mean, if you would want anything non-standard, you'd have to ask so mony wuestins, it's basically like asking someone elso to do all the designing for you. No that I believe that is your intention, but some people could interpret it that way. About the IN and OUT jacks: it is impossible to not be able to find that yourself, Smash's site is full of nice pictures, you'll succeed in finding the answer there (and will be much more satisfied finding it yourself, than just getting it read by someone else, believe me!) About the function of the IN port of the SID: by attaching a jack, you can run any (audio) signal through the 12dB fiter of the SID. You could even cascade one or more SIDs like that, but you lose the individual outs that way. Hope this helps, cheers, Alex.

No they're not! I keep yours in a special box beside my bed ;D

If you ever run out of working PICs again because of (similar) accidents, write me a PM or a mail, I may have some spares lying around of which I probably could spare one. Cheers, Alex.

100$??? What prices lately... As soon as my SID module is finished I'll test all of my remaining SID chips, and what I don't need (including spares) I will put up for auction. I'm going to be rich! ;D

Hi Moebius, I actually already read that topic, but I havent seen Hastings around lately, hence my question. The link that Smash provided to give a LIN pot a LOG feel is also in my "gathered electrical goodies docs" folder ;) I'll give it another study though, might find something I missed initially. thanks. /edit What do you know! :) Analog Devices does samples too! Sampled myself some AD5206BN10, AD5204BN50 and AD5204BN100 a few minutes ago. Because Hastings has already done some prototyping, to me these seemed favorable above the digipots microchip has. Also, the AD digipots are 6way, 4way and 4way, while MC only has 1 or 2 way specimen. I am very curious if my PSU design can make this combination of Digital and Analog circuitry quiet enough. Perhaps I'll use a separate Analog ground. Also, I believe Hastings used guitar-rated impedance for his circuit, and I recently learned (thanks Mendelt ;) ) that high resistors bring high noise, so I suppose there's still room for improvement. My test distortion circuit will have a switch to select Guitar rated impedance (typically 1MOhm) or Synth rated impedance (for example SID has 1KOhm). The test circuit will probably end up as a stand-alone effectunit in a 19" rack. My current test design can switch between 4 different clipping options, one of which is no extra clipping. I will evaluate the sound, and then develop a much slimmer distortion board with probably only one clipping option. People can then stuff the diodes they find best sounding. then, if I find some more time ( ;D ) I'll want to digitally control the distortion settings via the digipots. but that phase will probably be a few months from now.

Exactly. Come on Slorrin, if I can do it, you certainly can too! ;D I was in a bit cranky mood indeed, I think I have to apologise for that, but my intention was to get you reading. Not just the forum, uCApps is a far grater source of information than the forums alone. it's all there, some things are harder to find than others, and your answer is certainly not hard to find. Cheers, Alex.

OK, I'll share some more of my thoughts now this is a new thread :) I'm not sure how many digital pots can be driven from 1 core. If thinking from a quad-SID standpoint, maybe the slave cores could each drive the digipots attached to their respective FX units. If that's not possible, a dedicated FX core might be necessary, this core could then run an adapted MBCV firmware so you also have CV control over other stuff. I've read digipots introduce zipper noise. For my current project, the earlier mentioned distortion, this is not really a problem, as you usually don't do distortion-sweeps. Only the initial setting when changing a patch would create noise, and if you do asjust when playing I doubt the noise would be identifyable from the distorted signal anyway. Anyone here that's toyed around with digipots before? I'm ordering some samples from microchip next week, something to toy with until Smash's reopens. Cheers, Alex.

I keep one for sentimental reasons. I have a sampler and a midi-interface for it. Never used them, no time yet :-[ It just might come in handy to rip sounds from original SID tunes or something?

And I'm working on a distortionunit. Right now it's not even prototype phase, but the schematic I cooked up looks promising. Will need some adaptions to make it MIDI controllable, and to adjust the imput from guitar level (1MOhm) to SID/Synth level (1KOhm). Might even put a switch to select between both input levels, to make it more versatile. As a start I'm going to make it a standalone FX unit, with normal analog pots and switches, and a few different clipping options to select. Then I'll test them with the SID, and check what options sound best. Lastly, I'll <try> to swap the analog pots for digital pots, and make it controllable from a PIC. But that's all I'll say right now, it might make this completely dull thread intersting all of a sudden, that would be a shame now wouldn't it? ;D I would like a dedicated topic on the fx / midi thing, and am also very interested in Illogik's cookings! ;) Cheers, Alex.

You are killing a 128D for a SID!? :-[ :'( (If it's already broken I can understand)

Hi Wilba, I read your story about all the broken SID's you tried to salvage, what a pity. I believe I also read that stryd_one offered you a SID, so are you supplied now? If not, please PM me, I might be able to help you out (trade). (Note to other midiboxers: this is an offer to Wilba only, please do not PM me about SID's for sale if your name is not Wilba. I will open a separate topic if I ever decide to sell some). Cheers, Alex.

Hi Wilba, I don't think removing copyright notices is part of any Open Source license...?

I could answer this question in 2 seconds, but I'm not going to, since this info is so obviously available. Click on the uCapps button on the top of your screen. Then navigate to the SID module page. Read about the audio in. Then, if you want some more, read the info at SmashTV's shop info page for his particular SID board, it will tell you everything about the mounting of jacks. Good luck.

Cut it out you both! :( Smash is already doing everything he can for the community at a price that I can hardly imagine is cutting even. Now you want him to go even cheaper than that? The boards are already mass-produced, hence the low price for the high quality. If you want an easy step C SID just order the individual kits. If you want it cheaper, organise a bulk order for Reichelt or mouser or whatever electronics supplier, and order the plain boards. As he pointed out to me once (when I asked a similar ridiculous question): his time is worth money too.

Thanks, fixed now. Cheers, Alex.

Absolutely, but I think it would be better to test it first. Parts have been orderen from Reichelt (and they don't respond to email anymore as soon as you ask why the price is for a foreign order is 50 euro more than a domestic one >:( ) and also PCB's are arranged for. If the results are as we expect, .BRD and >SCH files will be released. (Into the WIKI I suppose). I -might- order a few extra PCB's if there's demand for it, when the PSU had been approved. Cheers, Alex.

I would design a power-over-MIDI adapter in the same way power-over-ethernet is done: create a box with a MIDI-in and Power-in, and a Power&MIDI-out. In your MIDIBox case you can take the power right off the pins at the inside of your MIDI plug. I'd definitely use DC, but I'm not sure what's the best place for the regulation: I don't know if the regulated voltage signal would deteriorate when transferred over some length of cable. If that's a non-issue: definitely place your regulating circuit in the PoM adapter. Accidentally swapping the wires is not possible this way, I don't recall ever hearing about anyone successfully inserting a 5 pin DIN plug the wrong way ;D Cheers, Alex.

Hi TK, when testing prototype builds of my PSU I have also seen higher voltages behind 78xx regultators. The explanation I got from more knowlegeable (than me) people was that the 78xx needs a load before it will regulate properly. That may not be the case here since his core boards is acting as a load, but is it a big enough load without PIC running....? Cheers, Alex.

This stuff RoXX! ;D I have an old acoustic guitar lying around, paid way too much for it as it was damaged beyond playability, maybe give it a second life as a midibox 8) I like the idea of power-over-midicable, will definitely research such an option!