Dave Smith Instruments SYNTHESIZERS

on 3/27/04 1:47 PM, Ugo wrote:

> when i've got my evolver synced to my sequencer's clock, the
> bpm display on the evolver jumps around some. for example,
> if i've got cubase SL transmitting at 120, the evolver will jump
> around between 119, 120, and 121.

this can be caused by (at least) two factors:

1. the clock being sent is not stable, and has some
   degree of jitter...and based on other people¹s
   comments re: Cubase, this is likely in your case.

2. the receiving device does not have a good algo for
   interpolating the incoming clock, or a method of
   hysteresis...I cannot comment on the Evolver¹s code.

> also, when i start cubase's sequencer, the evolver will first go
> to 101 and then jump up into the 119-120 range.

this is common because clock is derived as the timing
between pulses...there is no clock info in a single
pulse, so the Evolver is simply deriving the clock as
best it can from your source...the solution is to make
use of a blank measure or the like so clock can be
resolved by your slave devices before they need to
produce any audio.

> this problem evidences its self with all my other clock syncable
> gear too. the degree of instability in the clock sync varries
> depedning on the equiptment in question...with my korg kaoss 2
> being the most stable to my fizmo's sync being the most unstable.

yes, it is clear to me that different pieces of gear
produce different levels of quality as it regards timing
for MIDI clock...my most stable being my Elektron
MachineDrum and Clavia Nord Modular (never used the
Evolver as a clock source).

> for an external sequencer sync, the problem is usually not too
> noticeable since it usually jumps around in the right range closely
> enough and the jumps are very fast. but for synced delays, its a
> nightmare because (depending on the sync implimentation) i either
> get clicks or massive pitch glitches.

you will get one or the other...if you get clicks, it
means the delay algo is not interpolated...if you get
pitch warbles, it means it is interpolated.

> i've had this problem with other sequencers too so i know
> its not just a cubase problem. i've also experianced this with
> 3 different midi interfaces and on two OS's (XP and 98).

you may wish to use some other device than the computer
as your clock master.

you may also wish to consider not syncing delays to MIDI
clock, but setting the delay value by hand...in general,
this will work most all of the time (if not as
convenient).


cheers,
aeon