Waveshaper
mbartkow at ET.PUT.Poznan.PL
mbartkow at ET.PUT.Poznan.PL
Tue Apr 20 15:00:02 CEST 1999
----------
X-Sun-Data-Type: text
X-Sun-Data-Description: text
X-Sun-Data-Name: text
X-Sun-Charset: us-ascii
X-Sun-Content-Lines: 28
Here is my favourite waveshaper. This circuit idea was published in
Wireless World, several years ago. As you move the pot slider the
circuit slowly morphs from "aka-log" through almost linear to
"aka-exp". I love this extremely simple idea and have used it in my VCO.
Note, that feeding it with a triangle wave (e.g. from my favourite VCO
based on symmetric charge-discharge scheme) you get all the basic
waveforms without the need of separate nonlinear shaping and further
complicated crossfade. It is an ideal solution for a micro synth design.
The value of the pot heavily depends on the diodes used as well as
on the input signal amplitude. Typically I use 22k or 47k. OA is TL071.
have fun,
m.b.
--
Maciej Bartkowiak
========================================================================
Institute of Electronics and Telecommunication fax: (+48 61) 8782572
Poznan University of Technology phone: (+48 61) 8791016 int.171
Piotrowo 3A email: mbartkow at et.put.poznan.pl
60-965 Poznan POLAND http://www.et.put.poznan.pl/~mbartkow
========================================================================
----------
X-Sun-Data-Type: gif-file
X-Sun-Data-Description: gif-file
X-Sun-Data-Name: waveshp.gif
X-Sun-Encoding-Info: uuencode
X-Sun-Content-Lines: 50
begin 600 waveshp.gif
M1TE&.#=A7P'8 +, ( " (" @( @ " @(" @,# P/\ #_
M /__ __\ _P#______RP 7P'8 ,$__#)2:N]..O-N_]@*(YD:9YH
MJJXL"+SC"[=T;4]RG-]\[]^RF2>X^QF/F&"(*$0ZGU )<<AL1J\U);6*[7II
MTTU5^RV?R)IQT<QN<\))]=I-%\\M\GM]SX97Y ]H?(,X>E)J at 8:$BT]^AV.%
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M&#"8P[%Q-\YG^R]MH;IEL6QALVYQW[Q[ Y2-ZC at NB2J@YQ[>.KGSW<%=[>+,
M+46U.MVK6U?>4KJ9[\_1D)]KODRS?>.AH@\5GKL>YE7;:YM/,$M#:&X .(O_
M+?'5]T6!FY508( (9F=9, at UNIUU\_HW'8(2PJ<88AM=-:.%M'^;"X7X0<KB>
M/PN":-V%&)*X(7,"BA at B"RG*J!] !S:588PV2EA4A0E.@]=Y[['WFW?\*6B@
M>TERU2!\D^6XI'A!-C>DACZZ2!U""(IV98]14LEDEIIU..:67-9(99A2HCD.
MF$<6=2*1;)8786!UMCDGCJP]- at E^UEA9)7U'.M@/H,9D*-X/B)ZS8Z/MQ)FH
MI/WY "FCCRIJWZ _LO<9ITI>VJF1''V*I*:G+-979P^BRE69J\)U*J61 at LJ4
M2ZP"D:>&L.(J*PJ&RJ-J=KE^%*QG1NY:;*BTHG29_YE+>6DK7[LRV^N<RWXZ
MK32+Y?=/MC2Z&9VL/H*;;)]^2EL0FN;."BVOI KY2;MX;@O9MD8=1R^6U2)+
M[4VV[?MFG]W*^<JO*I)I;;P 6X5P::)F4K"=4PBLK;CP_NMDQ0\S:^]%ERVW
MIYU W at AQ9&J97)&[Z/*&7#XE?^DN/VNZ#&S$?\(,)3H)3WER/#OS?+.KSM)3
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M*+T4;H:$YF at A#PGEPYIAD(9#;,0-19;#!R(QB0F$(=GXMT,H9LQX4"IA%:VX
ML*;_%9"%6^2BO[ 8NI@(48PV%.%J@!BU)J(116KL'1MS]L0WAK"(,W/CF?1H
M1^#$L8=UQ%0@^^@Z*3+OC&F4(2%C1K/+!6N%P5/D(ET'-+&]+#V#G&0>F>9(
M2%Y.AYG4)+_XP:/5I2J,HL3.-N0UQUO5BH^I!(_G/,F[6$8%D49D!"YMR2)8
MYA*%ON1E!8.YILVA4I at L2V0H!X;,\"US<9(D8S/O14Q3$K&:TYQ--(MIHVP&
M<8>T-!8VO>G';<*G>N2D9B2?F9]TJA.8XW22.T'&SMII,Y[S;!4^1ZG$NOTN
MG]*$YS at OF*Q=IM.@//BGX"XE,X#*[90X\]FU$)I-BNJS_UF61-OB')I,4#8J
MHP_='4<UBDD3W6EV(PTI.$SZ))2FU)#Y8VF77/I2+Y94IFI*7TT#J at F%?LV$
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M'A,9PT=VX3&3K%4F at W#)3IZAD:-,0"H75L=69FJ6 XOE+1MSR%ZN<ICKV^4Q
BRQ+,9M9RF at V(YC4/<W!N5O$JXPQC3M+YEHV\LYZC$($ .QMS
end
More information about the Synth-diy
mailing list