MB808 tighter as a TR808...

[nuke]

...might be interesting for some of you... i stumbled across this site innerclock

so i ran a little test with my MBSeq808-Build...120 bpm, rimshot each quarter...and ended up like this:

22.029|22.072|22.075|22.025|22.077|22.028|22.079|22.030|

22.077|22.027|22.071|22.030|22.075|22.030|22.071|22.031|

...so the largest distance between two quarters is 52 samples...the tested 808 is 87 (on their site)

so a 1,18 ms drift compared to 1,97 ms...

what i was thinking of is , what cause the drifts? (not that i´m not satisfied with the results)

would it be an improvement when the two 33pF caps (C1, C2) will be matched as close as possible?

...this is just a guess...since i´m noob when it comes to electronics (but learning everyday ;))

nik

Edited December 4, 2010 by nuke

[latigid on]

?

Faster update rate for the trigger pulses

??

[nuke]

?

Faster update rate for the trigger pulses

??

...mmm....is this just a guess?...or do you think its the only way to avoid the jitter?...i assume then its more a programming aspect rather than selecting components, right?

ok...why i ask is because i thought of building such a "sync-lock" on my own (i would buy this- but it´s soo expensive for "just" a midiclock...also like to have more midiouts, like they announced with the cinq-lock)...so when it depends on "just" programming, thought it may be possible with a pic (maybe even with mios ) to get a stable samplebased midiclock via a trigger input...

i searched this forum and also the www and stumbled across several projects (pic and arduino-based), but they all seam to be kinda "dead", not further developed... :unsure:

the clockboxproject is great, but it also is heavily dependent of a stable midiclock from its source...would be great to have such a trigger-feature added to this...

cheers, nik

Edited December 4, 2010 by nuke

[waveformer]

...might be interesting for some of you... i stumbled across this site innerclock

so i ran a little test with my MBSeq808-Build...120 bpm, rimshot each quarter...and ended up like this:

22.0029|22.0072|22.0075|22.0025|22.0077|22.0028|22.0079|22.0030|

22.0077|22.0027|22.0071|22.0030|22.0075|22.0030|22.0071|22.0031|

...so the largest distance between two quarters is 52 samples...the tested 808 is 87 (on their site)

so a 1,18 ms drift compared to 1,97 ms...

what i was thinking of is , what cause the drifts? (not that i´m not satisfied with the results)

would it be an improvement when the two 33pF caps (C1, C2) will be matched as close as possible?

...this is just a guess...since i´m noob when it comes to electronics (but learning everyday ;))

nik

And how did you measure this ?

[nuke]

And how did you measure this ?

did u read the article on the innerclock site posted above?...they describe the procedure there...

i put the mb808seq as master at 120bpm with a rimshot each quarternote...in soundforge i sampled 4 measures...so 16 rimshots in total...the distance between two rims should be exactly 22.050 samples @ 44.1Khz...the results are posted above...i know its not 22.0029 ...should read 22.029 and so on, with a zero less (my fault, was a copy paste error :ahappy: ) <- corrected the readouts

Edited December 4, 2010 by nuke