After re-listneing some recordings I noticed audible and rather annoying distortion having keylock turned on. It sounds like someone walking with wet boots, just high pitched or the squeaky sounds from a mechanical keyboard. So I did some tests:
Happens when keylock is on, even at 0% pitch. Higher pitch makes it worse.
Tried with 44.1khz, and 96khz upsampled source files, still happening
Tried reducing volume from souce tracks first by -3db to eliminate intersample peaks, still happening
I uploaded two recordings of a loop where it happens, 0% pitch, keylock on and off.
Listen for yourself
My SC6000 is digitally connected to X1850 at 48khz sample rate, recordings for comparison were taken with audacity. Engine 3.3.0 and Mixer at FW 1.7. Other SC6000 has the same issue.
Would be nice to have it fixed, this way I can’t use keylock and it is an important feature for me, I try mixing in key mostly. Apart from that I love the hardware.
There are some other things I noticed but might deserve their own topics:
Played a track 24-bit 44.1khz and its upsampled 98khz version, recorded through X1850 (48khz) and compaired the zoomed in waveforms: The recorded upsampled track looks a lot closer to the original than the recorded original. Probably due to internal upsampling?
When recorded with the x1850 at 96khz the sound wave is kinda inverted and offset for short periods of 8 to 16 samples at random parts of the recording. I noticed when subtracting the recorded song from the original in audacity and there were random spikes. I tried different buffer size settings within the driver, different usb cables and different digital cables, all the same. This makes 98khz on the x1850 unusable for me (could still be issues with my laptop tho).
Artifacts within the audio are a trade-off of using key lock. I know Serato’s Pitch n’ Time plugin for SDJ sounds really really muddy on filtered kicks in house music. Even at 0% you still get the artifacts if it’s switched on.
If I remember, Claptone - No Eyes sounds like a duck quacking at the start.
The Elastique algorithm sounds usable but it’s not perfect. It’s also used in many other DJ vendors software too.
Honest opinion, Ive never really got the master tempo bashing, ive been using it for 20yrs now and can’t say ive ever heard a track sound noticeably bad.
Id rather have a pitched up or down track stay in key than the vocalist sounding like a chipmunk.
Yeah I can hear that, it’s almost double hitting the clap. im going to do some playing around with the function turned on and off to see what I can hear.
I do know from doing lots of 45 sets recently that anything more than about 3% pitch sounds ridiculous on real vinyl in most cases
I think for dance music its probably better to turn it off, the clips shared above sound like some kind of prog/tech type track, are those ever going to be pitched to extreme or even have elements that sound too bad if pitched?
I mainly use it as my DJ sets tend to be all over the shop mixing up different genres and beats so it just helps with any 6% pitched up mixes etc, for that kind of non-vocal, melodic stuff I reckon just turn it off.
I’ve read before that Engine OS uses the same time-stretch algorithm as Traktor, so I played the same song in Traktor and the distortion sounds very similar. Also tested it in Rekordbox where its less noticable and not as high pitched, which I prefer. The example I gave is not nitpicked, it also happens to a lot of other songs.
I mostly play subgenres of Techno, some songs at +6% and I’d rather keep the key and deeper bass. I’ve used Traktor often and only just noticed the distortion, so maybe it’s just one of these moments cause now cant unhear it.
Then I guess it’s an issue with Elastique itself and there is not much that can be done about it by the Engine developers, apart from maybe tweaking some parameters and I’m sure they’ve done that already.
I also noticed the recording of a track played at 0.0% was still a bit faster than the original. That might explain why distortion is also there at 0% pitch: Its a continuous fader and never truly at 0%, so it wouldn’t make sense to bypass when it can just be turned off then.
The Serato Example from above sounds …interesting.
And the best result I got so far was from Audacity’s algorithm, it’s not real-time and took about 5 min for a 7 min song…, but I might consider time-stretching beforehand for pre-planned sets.
