Playback Quality - turntable/vintage setting

Hi all:)

Can someone please tell me what that nasty high pitched whine sound is when i change the pitch in turntable mode of GAse4?
(Also in vintage mode, but not so much)



That sound are explicit aliasing artifacts. I once explained the background in the GA4 announcement thread:

Playback quality modes
Sometimes there are features that hold more than you’d expect at first. The new playback modes in the Beat Agent are these kind of features. Why is it that so many contemporary producers still relay on these old school drum machine heavyweights? It is the 12-bit special sound that adds crispness to your drums and samples. So, in order to make a serious approach to emulate this sound, the team analyzed some of the classic 12-bit drum samplers to get to the bottom of the sound, recorded different samples, from drums to sine sweeps, and experimented with different ideas to replicate the signal flow. As a result, we came up with two different modes: the vintage and the turntable mode. The vintage mode is basically a “high-quality bit-crusher-resampler” that reduces the bitrate to 12 bits and resamples to 26.04 kHz. Add some distortion with the hard clip filter and you will get pretty close to the vintage drum sound that is so popular in hip hop and electronic productions. But that’s only half the story. The limitation of the classic 12-bit drum samplers has always been the memory that only allowed a sample time of about 2.5 seconds. In order to get longer samples into the memory the samples had to be recorded by switching the turntable from 33 RPM to 45 RPM, recording the samples at a higher speed of about +35% and then pulling them back down by just about 5.2 semitones within the sampler. This workaround had significant impact on the sound since it created explicit aliasing artifacts. Exactly this aliasing side effect can be heard when you pitch samples in the vintage mode. In turntable mode the recording at a higher speed and down pitching is simulated in advance to include the aliasing automatically. It may sound strange that adding aliasing artifacts should be a desired effect to enhance a sound, but basically that’s the stuff.

We could have added fixed distortion or low-pass filters and even crackle noise as included with some of the other VST instruments, but that just didn’t feel right. The control of these aspects should be left in the users’ hands. What do you think differently about it?

Hi matthias:)

Thanks for this insight on how GA vintage/turntable modes operate.

-nice history lesson - where these artifacts desirable back then or “mittel zum zweck”?:stuck_out_tongue:

-i like the sound when it is unpitched though-> maybe we can implement a “modern take” on the 12 bit machine in some update? Idk, just a thought:p (best of both worlds):wink:

Either way, your explanation and the GA’s teams’ striving for authenticity impresses me. Tru skool;)

Thanks and have a nice weekend:)

You can think of it like amp overdrive or tape saturation and compression. These were all things that where initially seen as a problem, but people grew to like the sound.

If the artifacts stick out too much in your mix you can always tone them down a bit using an EQ or a filter.