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SAMPLE TUNING 

 

 

This is one of the main exciting features of the Linn LM-1, unlike its successor the Linndrum, the 
LM-1 had a tuning knob per voice, for ALL the voices. 

 

 

How the system works is not too hard to understand, a monolithic function generator chip XR2206 
was used as a clock source for EPROM  content reading. The XR2206  output frequency will determine 
the frequency at which the EPROM content will be read (speed of the counter chip) hence the 
sample rate. 

 

XR2206 Datasheet tell us that the frequency is determined by the external timing capacitor across 
pin 5 & 6 and the timing resistor. The LM-1 used R1 & R2 (a potentiometer) to set the value of the 
timing resistance. This configuration is the same for each voice. 

 

 

 

Summary of Contents for LM-1

Page 1: ......

Page 2: ...LM 1 DRUMS www alyjameslab com USER MANUAL 1 0 BY Aly James 2014 2015 ALYJAMESLAB ...

Page 3: ...6 CONTROL PANELS 9 THE AM6070 DAC 11 SAMPLE TUNING 15 THE HIHAT CASE 18 MAIN PANEL 19 CEMFILTERS 19 SETTINGS 22 EPROMLOADING 24 PRESETS IMPORT EXPORT 27 MIDI AUTOMATION 28 LM 1 SEQUENCER 29 HIDDEN SECRETS 31 LINKS 32 DISCLAIMER LICENCE AGREEMENT 33 ...

Page 4: ...e 80 s drum machines Tothisday the unique soundof the LM 1 is highlyregardedandonlyusingsamplesof anLM 1 outputcannot reproduce the wide range of soundsthismachine canproduce The DAC in use in here and the whole circuitry stands next to the samplescharacters in that unique soundingteam The LM 1 is an historical piece of gearthathas a place in the soundof the 80 s era Only around 500 of these thing...

Page 5: ...a special groove andevenakindof secret randomizationbuiltin Thisisplainfalse asRogerLinnhimself have recentlystatedanddebunkthe myth the LM 1 groove onlycomesfromthe low resolutionof itssequencer whichis 48PPQN see LM 1 Sequencersection This emulation is based on reverse engineering and old datasheets it usesa C customcorewith modeled AM6070 DAC Oscillators counters OPAMPS Filters The producthasbe...

Page 6: ...ng the range available is 978 Hz 44092 Hz which correspond to a real mod you can apply to the Linn LM 1 to increase the pitch range stock was 12048 Hz 30303 Hz See Sample Tuning Seven of the stock LM 1 EPROMS can be replaced by external compatible content and an additional voice can also be used This opens up to Linndrum sounds often called LM 2 DMX Drumtracks etc and even your own created EPROM c...

Page 7: ...ntto use it witha 64bit DAW you can use JBridge or internal DAWBridge INSTALL VST 1 Decompressthe downloadedarchive file 2 Copythe entire FolderVLINNtoyour VSTPLUGINS folder 3 Load it inyourDAW INSTALL STANDALONE 1 Decompressthe downloadedarchive file 2 Copythe entire FolderVLINN_STANDALONEwhere youwant 3 SimplyRUN VLINN exe ...

Page 8: ... filteredto minimize the remaining8bitnoise usingaVCFconfiguredasa4 poleslow passfilterwithno resonance The CV frequencyof the VCFwasshapedbythe circuitryin a way that letsthe transients pass throughrelativelyunfiltered The VLINN letsyoufinetune the CV pulse orcompletelybypass the filter thisisuseful whenavoice istunedverylow orif youwantto replace a Bass slotwith anotherEPROMthat doesn trequire f...

Page 9: ...tof the parameterslike volume andpitchknobscanbe MIDI learnedand controlledbyanexternal MIDIHardware LOADING EXTERNAL EPROMS DATA The VLINN providesthe abilitytoreplace some voiceswithexternal compatible 8bitcompanded EPROMdata whichopensupthe machine to LINNDRUM LM 2 samples LINN 9000 DMX DX DRUMTRACKS etc Evenloadyour owncustommade You can switchbetweencustomloadedand stock EPROMS onthe fly VLIN...

Page 10: ... some not andhence the doublepadsonBass Snare Hihat Tamb Cabasa Toms Congas pads trigger either the high or low voice Note that the high Tom or Conga can be tuned lower than the low corresponding voice this is basically just a name to differentiate the two voices Once a voice is triggered a red LED indicates the status These are the main panels than can be reached by the panel buttons to the left ...

Page 11: ...Right click on a knob button orslider will open a midi learn assign menu Ctrl click moveallow fine tuning ...

Page 12: ...THE AM6070 DAC ...

Page 13: ... pretty expensive and storing digital data in a tiny space was the way to go The LM 1 samples were stored in µ 255 companded format in 8 bit this is the main task of the AM6070 to turn this digital encoded data into an analog voltage byte after byte If you try to importa raw binaryEPROMimage in for example an audio editor like Audacity you will endup witha bunchof noise because companded format is...

Page 14: ...hit down itwill notsoundthe same and dependingonthe interpolationmethod will soundreallylessbrightandnasty Keeping the same gritty 8 bit sound at any pitch was very important for VLINN VST to produce an accurate output Here is a comparison between a down pitched LM 1 Claps sample at 13000 Hz in a modern audio editor VS a 13000 Hz tuned claps in VLINN VST among the differences one is clearly visibl...

Page 15: ...70 Datasheet has been use in the VLINN Code for accuracy The fact that the VLINN decodesthe EPROMcontentinreal time givesitthe ability to import EPROM binaryimagesasa replacementforcertainstockvoices like youcoulddoona real LM 1 See EPROM Loading ...

Page 16: ...XR2206 was usedasa clock source forEPROM contentreading The XR2206 outputfrequencywill determine the frequency at which the EPROM content will be read speed of the counter chip hence the sample rate XR2206 Datasheet tell us that the frequency is determined by the external timing capacitor across pin 5 6 and the timing resistor The LM 1 used R1 R2 a potentiometer to set the value of the timing resi...

Page 17: ...rt of an LM 1 schematics that shows how the XR2206 is connected and what values were used for the timing capacitor timing resistor s for the Cabasa voice Following the datasheet we know that frequency is given as f0 1 RC Hz ...

Page 18: ...K pot by a 10K pot gives a lower minimum of 7512 Hz This table shows the values I used for the VLINN VST range You can do the same on a real LM 1 simply by replacing potentiometers and resistors by the values in this table I made So you are able to set the tuning frequency from 978 Hz to 44092 Hz in VLINN VST this has been set to 1000 Hz to 44100 Hz for convenience Notethata common usagein recordi...

Page 19: ...ifferentlyonthe output For closedhihatthe circuitryhadthe abilitytodischarge the currentthroughanadditional waybased on the decay potentiometersetting Thisbasicallymakesthe hihatsoundingdifferentoneveryhit and kindof givesita live feel The LM 1seemstobe the onlydrummachine of that time to dothis clevertrickthat way eventhe Linndrumdoesn thadit Thisdischarge followingaclassicnatural Decibel likecur...

Page 20: ...MAIN PANEL Each voice has a volume level simples as old vintage hardware These sliders can be MIDI learned or automated as most of the VLINN parameters See Automation CEM FILTERS ...

Page 21: ...uredinmanywaysto produce differenttype of filtering inthe LM 1 case it was basicallyconfiguredasa4 PolesLow Pass Filterwithno resonance The CV whichcontrolsthe frequencyof the VCFwasshapedby the circuitry in a way that letsthe transientspass through relativelyunfiltered The VLINN letsyoufine tune the CV pulse orcompletelybypassthe filter thisisusefulwhenavoice istunedverylow or if you wantto repla...

Page 22: ...ndsletsyou fine tune the voltage pulse that controls the VCF frequency the greater the offset the more transients will remain unfiltered this ranges from 0 300 Ms RESET sets it back to default Default has been tuned to 30 Ms The graphic line represent the shape of the Control voltage the lower the graphic point the more it is filtered ...

Page 23: ...ity to Max or Middle velocity depending on the incoming velocity if above 64 it will be LOUD else is quiet FULL Thiswill applythe full range of 127 MIDI velocity levels however this features wasn t possible on a real LM 1 without heavy modifications So why implement it in VLINN Well usuallyyoucontrol the individual volumesof arecordedsequence while playing it back this allowedlivemodification over...

Page 24: ... SINGLE Thiswill route all the voicestothe firststereopairwhichislabeledasBASS because it also serves as the BASS only output when set on MULTI MULTI This will route all the voices to a separate output labeled with the voice name You have to enable the multiple outputs in your DAW Each DAW has its way of doing it but it is generallystraightforward The multiple outputs let you MIX easily the VLINN ...

Page 25: ...erent on certain model the Linndrum Kick seems to be often used as a replacement through the years The stock LM 1 sounds are written in the ears of those who have experienced the 80s funk vibe as were the Linndrum ones but the LM 1 is definitely the fattest Custom EPROMS The VLINN features an import function for compatible EPROM Binary Images bin files This kind ofworks in a vintage way Mainlybeca...

Page 26: ...don t do it after because changing the size of a custom slot will erase the memory of the PROM to ensure the next loaded data will not be corrupted Note that the EPROM sizes available correspond to typical format you might find and most of the samples you will load will fit in ...

Page 27: ... ADD CARD voice is an additional voice that is always set to CUSTOM which means that it does not contain data unless you load some in Notall the voicescanbe replacedbut7 of them can the ones marked VCF will benefit from the CEM filtering replacingthe HIHATwill pass through the VCA and the Decay will work on it the loopingcapabilityof the STOCKHIHAT is unique for the STOCK HIHAT so the CUSTOM loade...

Page 28: ... Try to record your sample at 22050 Hz so as you can have a nice range of tuning PRESETS IMPORT EXPORT FXP FXB VLINN can load and import its own format presets banks All Custom EPROMS file paths are also saved with the patch All MIDI LEARNED ASSIGNED parameters will also be saved with the patch Simply name the preset and right click the PROGRAM MENU to save either 1 preset or the whole bank you ca...

Page 29: ...N parameters can be automated via midi learn or DAW automation allowing great control over the sound Simplyrightclickona button knobor slidertoassignexternal MIDIControl or use DAW automation Almostall type of MIDI message canbe assignedorMIDI learned ...

Page 30: ... Butwhathappenswhenyouuse a swingvalue andquantize Yeah some noteswill be shiftedbyx amountand theywill be storedinone of the possible place accordingto the PPQresolution Vintage DrumMachine such as the LinnLM 1 had a 48 PPQ sequencer whichissmallerthanmodern sequencersbutstill enoughtoprovide some goodtiming RogerLinnintroducedthe shufflefunction betterknownastoday sswingoffering50 54 58 62 66 an...

Page 31: ...DI file butspecifythe resolutionto48 PPQN mostDAWcan dothis Import it back and compare to the original thisdoesnotmeansit will soundbetterorworse buta little different apparentlypeopleseems toprefers48 PPQN hence more quantizedthings Of course if youtry thison a straight1 16 quantizedbeat nothingshouldchange Thisis the mainreasonI didnot feltthe needtoemulate the LM 1 sequencerinVLINN VST You can ...

Page 32: ...or API Equalizers Some artists useda lotthe variable pitchavailable on tape recordersto make effectsor drastically change the pitch of the final recording I don t know exactly why but the simplicityof the LM 1 scream for experimentationsohave fun with it and try things What modernDAWS offerin term of automation is a real improvementbecause inthe good old days you have to make pitch automation for ...

Page 33: ...utube com alijamesproduction Soundclouddemos http www soundcloud alyjameslab Twitter alyjamestwitt CONTACT alyjames info gmail com External links RogerLinn Website http www rogerlinndesign com ELECTRONGATE Archive http www electrongate com dmxfiles downloads html PROMENADESoftware http www electrongate com dmxfiles promenade index html HOPE YOU HAVE FUN WITH THE VLINN ...

Page 34: ...y not sublicense rent lease convey distribute copy modify translate convert to another programming language decompile or disassemble the Software for any purpose You may only redistribute the Software for promotion purpose with Aly James prior written permission Where redistribution is authorizedinwriting by the Author VLINN must be redistributed in its original archive format and must not be modi...

Page 35: ... 2014 2015 ALYJAMESLAB ...

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