Lwm MIDI rau CV Box: 7 Kauj Ruam (nrog Duab)

2024 Tus sau: John Day | [email protected]. Kawg hloov kho: 2024-01-30 09:25

Lwm qhov MIDI rau CV lub thawv yog qhov haujlwm kuv tsim thaum Korg MS10 khob qhov rooj thiab muab tso rau hauv kuv lub studio. Ua qhov kuv teeb tsa hnyav cuam tshuam nrog MIDI kom siv lub tshuab thiab ua ke txhua yam twj paj nruag, thaum kuv yuav MS10 thawj qhov teeb meem kuv yuav tsum tau ntsib yog yuav ua li cas thiaj li tswj tau.

Korg MS20/10 tsis yog qhov yooj yim synths los siv MIDI rau: ua ntej tshaj plaws, lawv vam khom Hz/V kev tswj hwm (kev sib txheeb tawm ntawm kev tswj qhov hluav taws xob thiab kev ceeb toom zaus), tsis yog oct/V (1V ib octave); thib ob, txhawm rau ceeb toom koj yuav tsum xa lub qhov rooj tsis zoo thiab luv cov lus nkag rau hauv av (S-Trig), tsis yog +5 V teeb liab (V-trig).

Muaj ntau yam kev lag luam daws teeb meem los tswj cov cuab yeej niaj hnub no (piv txwv li Arturia Beatstep Pro, Korg SQ-1, Kenton Solo) tab sis kuv yog ib tus neeg khav theeb pheej yig thiab txawm tias 100 euros ntau dhau rau "tsis hnov suab" ntaus ntawv:).

Nov yog peb tam sim no: cia kuv qhia koj yuav tsim nyiaj txiag tsawg MIDI rau CV lub thawv kom tswj/siv lub tshuab ua ntej MIDI synth lub suab, lub qhov rooj, nrawm thiab txiav tawm nrog MIDI maub los sab nraud (Keyboard, DAW, sequencer lossis xijpeem).

"Dab tsi txog MS20 mini tshiab?"

Raws li yuav luag txhua tus paub, MS20 tshiab yog qhov tseeb MIDI npaj: IN nrog 5 tus ncej MIDI txuas thiab IN/OUT nrog USB txuas.

"Yog li, yog tias kuv muaj MS20 mini qhov no tsis muaj txiaj ntsig!"

Zoo, tsis muaj. MS20 mini lees paub tsuas yog ceeb toom rau/tawm cov lus thiab cov keyboard tsis nrawm nrawm. Tsis muaj txoj hauv kev los kov yeej qhov no nrog MS10/20 vintage lossis mini keyboard, tab sis nrog lub thawv midi thiab cov keyboard nrawm nrawm koj yog xim kub. Ib qho ntxiv, nrog MIDI lub thawv koj tuaj yeem siv lim lim tawm (lossis lwm yam ntsuas qhov ntsuas hluav taws xob) lossis nws tau hloov pauv los ntawm MIDI cov ntawv ceeb toom ntawm qhov nrawm. Ib zaug ntxiv, tsuas yog MIDI channel MS20 mini teb rau yog channel 1. Nrog lub npov no koj tuaj yeem kov yeej qhov txwv no ib yam.

"Yuav ua li cas yog tias kuv muaj Oct/V synth?"

Tsis muaj teeb meem! Cov cai kuv tau sau yog sib haum nrog Lub Kaum Hli/V synthesizers (tsis tau sim, tab sis kuv ntseeg tias yuav ua haujlwm tawm ntawm-lub-lub thawv;)).

Kauj ruam 1: !! Nco Ntsoov Ceev Faj - Disclaimer

Koj cov cuab yeej muaj nqis heev thiab yuav tsum tsis txhob siv los ua qhov ntsuas.

Qho khoom ua si nrog hluav taws xob tuaj yeem ua rau koj cov cuab yeej puas tsuaj lossis ua phem rau koj tus kheej.

Kuv tsis tuaj yeem tuav lub luag haujlwm rau kev puas tsuaj rau koj cov cuab yeej/kho vajtse lossis txawm tias koj tus kheej los ntawm ib qho ntawm cov software lossis cov tswv yim lossis cov ntaub ntawv lossis cov txuas uas kuv tau tshaj tawm hauv cov lus qhia no.

Koj tau ceeb toom!

Kauj ruam 2: Engineering Kho Vajtse

Arduino los ua ke thaum ua haujlwm nrog cov haujlwm zoo li no. Lub neej nyob ntawm Zej Zog loj thiab cov tsev qiv ntawv zoo heev uas nthuav tawm yuav luag txhua txoj haujlwm ua rau nws xaiv qhov yog. Ntawm no pawg thawj coj yuav tau teeb tsa xws li nws yuav nyeem cov ntaub ntawv MIDI thiab tom qab ntawd yuav xa cov hluav taws xob tsim nyog los tsav:

- Suab, los ntawm kev hloov pauv pwm rau hauv qhov hluav taws xob sib piv kom tsav VCO ntawm digital rau analog hloov pauv (DAC)

- Tshaj tawm, los ntawm kev lim cov pwm tawm los tsav VCA nrog cov lim RC yooj yim

- Lim Txiav Tawm Zaus, los ntawm kev lim lub pwm tso tawm kom tsav VCF nrog lub lim RC yooj yim

- Rooj vag, ncaj qha los ntawm digital tawm thaum V-trig (muab 1Kohm ua ke nrog cov khoom tso tawm kom txo qhov ntws tam sim no) lossis los ntawm ib qho yooj yim pnp transistor hloov tawm ntawm cov digital tawm (saib schematic txuas nrog cov lus qhia hauv kauj ruam).

Arduino tsis muaj peev xwm ntawm kev tso tawm ncaj qha qhov hluav taws xob, tab sis 0/+5 V mem tes nrog ntau lub sijhawm (PWM). Peb tab tom xav tau digital rau analog hloov pauv (DAC) rau lub ncuav. RC lim dej yog qhov yooj yim DAC kuv tuaj yeem xav txog. RC lim tau zoo txaus rau qhov ntsuas hluav taws xob tswj lub zog thiab lim (VCA thiab VCF). RC cov ntxaij lim dej raug txiav kom ua rau muaj kev txiav tawm ntau zaus <20Hz (qis tshaj qhov hnov tau).

Kuv tau ua qee qhov kev sim nrog lub peev xwm qis uas tsis yog cov kab hluav taws xob sib txawv thiab kuv tau xaus nrog lub peev xwm ntawm 0.1uF kom haum zoo tshaj plaws. Kuaj tau zoo ntawm MS20 MKII.

Hmoov tsis zoo, peb tsis tuaj yeem tso siab rau RC lim kom tsav qhov ntsuas hluav taws xob tswj oscillator (VCO) vim nws yuav tsis raug qhov txaus (hauv Hz/V nplai, nyob rau sab qis kawg ob adiacend semitones sib txawv rau tsawg dua 0.02V; hauv V) /oct ob adiacent semitones sib txawv rau 0.083 V); peb yuav siv IC DAC (MPC4725) rau qhov no.

Paub Txwv

Txwv tsis pub tsav hluav taws xob rau 5V (Arduino tso zis hluav taws xob), tag nrho 0 txog 5V thaj tsam tau them rau qhov nrawm; qhov kev txiav tawm yog ib nrab them (-5V txog +5V); VCO ntau yog ib nrab tau suav tias yog hauv Hz/V qhov hluav taws xob ntawm 8 V yuav xav tau kom mus txog 440 Hz A4. Nrog qhov 5V tso tawm qhov txwv peb tuaj yeem ua suab oscillator mus txog D4 zaus hauv Hz/V.

Kauj Ruam 3: Daim Ntawv Teev Npe

Koj xav tau:

1X Arduino UNO (lossis nano)

1X MPC4725 DAC pawg thawj coj saib

4X 1/8 "lossis 1/4" mono txuas

1X MIDI txuas

1 X 6N138 optocoupler

1 X 1N4148 diode

1 X 220 ohm 1/4 W resistor

1 X 470 ohm 1/4 W resistor

1X 10K ohm 1/4 W resistor

4X 1K ohm 1/4 W resistor

2 X 0.1 uF capacitor

1X BC547 pnp transistor (thaum S-trig)

1X ABS lub thawv (tsawg kawg 55 x 70 x 100 mm)

….

Daim ntawv ceeb toom tias hauv cov duab saum toj no kuv tus qauv ua rau nce 100 uF lub tshuab hluav taws xob, tab sis lawv qeeb dhau vim tias lub sijhawm muaj peev xwm them. Lub peev xwm ntawm 0.1uF yog qhov kev xaiv raug.

Kuv siv txuas txuas ntxiv los muab lub zog rau kuv tus arduino; nws tsis tsim nyog ua tau kua txiv lub microcontroller ncaj qha los ntawm onboard mini USB txuas.

Kauj Ruam 4: Kev Sib Txuas/Schematics

MIDI IB

MIDI IN Circuit yog qhov yooj yim thiab piav tau zoo hauv net. Ua qhov no qhia tau zoo ntawm MIDI thiab Arduino los ntawm Amanda Gassaei, piv txwv. Kuv ua tus nth schematic ntawm qhov teeb meem lawm.

Daim ntawv ceeb toom tias kuv ntxiv qhov hloov pauv hauv MIDI IN cov phiaj xwm (hloov 1): qhov no yog qhov tsim nyog thaum rub tawm daim duab tshiab rau Arduino vim tias opto cuam tshuam nrog RX kab txawm tias tsis muaj cov lus midi nkag. Koj yuav tsum qhib qhov kev hloov ua ntej rub koj daim duab los yog IDE yuav tsis xa cov duab tshiab.

Thaum kawg koj tuaj yeem hloov kho daim duab kom siv cov software sib txuas lus.

DAC, RC Lim, Synthesizer

Kev sib txuas rau DAC, RC lim thiab Synth (suab, rooj vag thiab tshaj tawm) tau qhia hauv daim duab saum toj no. Kuv coj mus siv Korg MS20 thaj vaj huam sib luag, tab sis kuv sim txhua yam ntawm MS10 ib yam nkaus. Kev sib txuas ncaj qha ntawm CV nrawm rau VCA "thawj qhov tau txais" thaj ua rau thaj tsis muaj txiaj ntsig (Kuv yuav tsum khawb qhov no ntxiv) tab sis yog tias koj txuas nws mus rau "Tag Nrho" thaj ua rau thaj thiab nce koj tag nrho cov lauj kaub sab nraud (MG/T. EXT), koj yuav hnov lub suab zoo sib txawv raws li lub luag haujlwm ntawm daim ntawv tshaj tawm.

Kuv cov duab (thiab kuv tus qauv ib yam nkaus) tsis txhob siv qhov txwv tam sim no ntawm DAC cov zis, tab sis nws ib txwm yog lub tswv yim zoo los tso ib qho kom ntseeg tau lub neej ntev rau koj cov khoom siv hluav taws xob. 220 ohm resistor yuav txaus.

Daim ntawv ceeb toom tias hauv cov duab saum toj no 100 uF electrolitic caps tau tshaj tawm, tab sis lawv qeeb dhau vim tias lub sijhawm muaj peev xwm them. Tsis yog polarized, 0.1uF lub kaus mom yog qhov kev xaiv raug.

Rooj vag Tawm

Nyob rau hauv rooj plaub koj yuav mus rau ntu sib txuas ua ke nrog V-Trig (qhov ntsuas hluav taws xob) cov cim, 1k ohm series resistor los txo qhov ntws tam sim no yuav txaus; nyob rau hauv rooj plaub ntawm S-Trig (hloov txhais) synth, koj tuaj yeem siv qhov yooj yim PNP hloov hluav taws xob (saib cov phiaj xwm txuas nrog).

Kauj ruam 5: Software

Kuv tau sim khaws daim duab kom meej thiab "nyeem tau" raws li ua tau.

Kuv tau ua haujlwm ntawm daim ntawv yooj yim uas kuv pom ntawm no kom tau txais Voltage Vs Note# nkhaus thiab siv ncaj qha qhov sib npaug hauv microcontroller. Qhov sib npaug yog qhia hauv kab lus saum toj. Kuv siv C2 raws li kev ceeb toom kom tau txais Arp/Korg ua raws li Voltage Vs kev sib raug zoo (C0 - 0.25V, C1 - 0.5V, C2 - 1V, C3 - 2V, C4 - 4V, C5 - 8V thiab ntxiv rau).

Kuv yuav tsum tau txhais qee qhov sib txawv rau cov khoom ua si nrog txhawm rau kom tau txais qhov ua tau zoo … siv koj lub sijhawm los nrhiav qhov tseeb raug. Tus tuner yog qhov tsim nyog.

Peb tab tom yuav nce pwm zaus ntawm Timer/Counter txhawm rau txo cov zis hluav taws xob ripple (yooj yim li kab kab ntawv).

Txhawm rau kom cov cai teb rau cov bytes nkag, txoj cai vam khom hnyav rau kev ua haujlwm rov qab.

Koj tab tom xav tau Sparkfun's "Adafruit_MCP4725.h" thiab Plaub caug Xya Teeb Meem/Francois Zoo tshaj "MIDI.h" cov tsev qiv ntawv los ua ke! (Ua tsaug ntau rau cov neeg no: tsis muaj lawv kev rau siab ua txoj haujlwm no yuav tsis muaj qhov ua tiav!).

Kuv yuav xav tias koj muaj Arduino IDE npaj hauv koj lub PC thiab koj paub yuav thauj cov duab kos rau koj li Arduino board.

Kuv tsis yog tus coder hauv lub neej tiag tiag, yog li nws zoo li qhov kos duab tuaj yeem sau ua txoj hauv kev zoo dua. Kuv qhib rau cov lus qhia (Kuv ib txwm kawm qee yam saib coder code;))

Cov ntawv sau ntxiv tau sau hauv cov cai hauv qab no. Nruab ob lub tsev qiv ntawv, qhib cov ntawv txuas ntawm koj li IDE, txuas koj lub rooj tsavxwm, xaiv hom pawg thawj coj saib thiab rub tawm.

Kauj ruam 6: Troubleshooting

Txawm hais tias txoj haujlwm yog qib qis, muaj ntau yam uas tuaj yeem ua tsis raug. Yog tias koj tab tom ntsib teeb meem thaum sim tsim koj tus kheej MIDI rau CV lub thawv, ua raws cov theem no:

1. Nco ntsoov tias Arduino tau txais cov lus MIDI raug

Txheeb xyuas cov channel tso tawm koj cov keyboard lossis DAW lossis Sequencer tab tom tso MIDI cov lus rau. Arduino tab tom mloog channel 1 los ntawm lub neej ntawd. Upload "TEST_MIDI_IN.ino" los nyeem cov lus ceeb toom xa tuaj.

2. Muab ob npaug rau xyuas koj lub wirings

… Los yog zoo dua: triple txheeb xyuas lawv! Khaws koj lub sijhawm rau qhov no.

3. Txheeb xyuas qhov chaw nyob DAC thiab tso tawm

DAC tuaj yeem teeb tsa kom tau txais cov ntaub ntawv ntawm qhov chaw nyob sib txawv dua li qhov kuv tau teeb tsa hauv daim duab. Txheeb qhov chaw nyob los ntawm kev khiav "I2C_scanner.ino". Yog tias "tsis pom lub cuab yeej" ua yuam kev tshwm sim, txheeb xyuas koj lub xov tooj DAC (SDA thiab SCL cov tswv yim sib txawv ntawm txawv pawg Arduino sib txawv!) Yog tias koj muaj oscillocope (txawm tias cov 15 euros cov oscilloscopes digital yog qhov zoo txaus … thiab lom zem rau cov khoom ua si nrog!) Koj tuaj yeem tshawb xyuas qhov tso tawm ntawm koj DAC los ntawm kev xa cov duab hluav taws xob peb tog piv txwv nrog DAC lub tsev qiv ntawv teeb tsa.

Nco ntsoov tias thaum lub optocoupler txuas nrog RX cov tswv yim ntawm koj lub rooj tsav xwm arduino, koj yuav tsis tuaj yeem xa daim duab tshiab !! Muab qhov hloov pauv (nws tuaj yeem yog jumper yooj yim) ua ntej RX tus pin.

Feem ntau ntawm cov ntawv xeem no tsis yog kuv li lossis tsawg kawg raws li cov khoom siv online uas twb muaj lawm.

Qhov no suab tsis zoo rau kuv !?

Qhov no tsis yog qhov teeb meem tiag tiag: qhov sib npaug muab rau Hz/V tswj yog "zoo tagnrho". Qee qhov kev txav los ntawm tus cwj pwm zoo tuaj yeem nce los ntawm +5V koj tab tom muab tsis yog 5.000V, los ntawm DAC thiab los ntawm qhov ntsuas nws tus kheej. Txhawm rau daws koj yuav tsum ua ntawm koj lub suab sib dhos/suab kho lub suab zoo thiab "voilà" ua tib zoo mloog MIDI tswj;)

Kauj Ruam 7: Pab Txuas

en.wikipedia.org/wiki/CV/gate

www.instructables.com/id/Send-and-Receive-…

www.songstuff.com/recording/article/midi_me…

pages.mtu.edu/~suits/NoteFreqCalcs.html

espace-lab.org/activites/projets/en-arduin…

learn.sparkfun.com/tutorials/midi-shield-h…

provideyourown.com/2011/analogwrite-conver…

www.midi.org/specifications/item/table-3-c…

arduino-info.wikispaces.com/Arduino-PWM-Fr…

sim.okawa-denshi.jp/en/PWMtool.php