Clean FM tones?

[JamesT]

Hello

 Recently bought the Preenfm2 and am enjoying very much, but having trouble getting clean sub sounds with the sine and square waves. There seems to be distortion at lower frequencies? Is this normal? I have tried the suggestion of not enough power supply. I bought the unit brand new from Boxmusic and don’t particularly want to open it up to look at the dac’s as would have thought it would be assembled correctly. OS system 2.21. I haven’t compared it to my TX81Z, maybe it’s just an fm thing?

[lokki]

Are you talking about the slight sizzle when a sine wave is decaying? Or some sort of other distortion?

[JamesT]

 Here are two examples in comparison to a TX81Z(the Preen being the first in each clip).

 The Preen is set with just one instrument alg1, velo 0, voice 2 on a sine wave. Filter off gain 0.51, Vol turned 3/4...if the volume is turned all the way up another distortion is introduced.

 I love the Preen and what can be done with it especially in the stereo field...just want to know if there is something wrong with the dac's on my new unit. The gain staging is quite strange as the filter doesn't not seem to mitigate the 'ghost' distortion if you will.

Maybe I should try a previous OS?

can't seem to embed soundcloud in this post unfortunately.

https://soundcloud.com/timeron/preen-vs-tx81z-sine-01?si=51a4a163c8404a6fbe72afeff9ba5dc8&utm_source=clipboard&utm_medium=text&utm_campaign=social_sharing

https://soundcloud.com/timeron/preen-vs-tx81z-sine-02?si=f43a43825d1c45e0b6af095458a0d97e&utm_source=clipboard&utm_medium=text&utm_campaign=social_sharing

[Xavier]

Do you see "24 bits DAC" when you turn on your preen on the 4th line ?
If not, I think you have the previous 18bits version which was not very good at pure sin waves.

[JamesT]

 Hi Xavier,

  How do access this information on the Preen? On starting up it just has your name and the OS?

 Many Thanks

 J

[Xavier]

Hi Xavier,
  How do access this information on the Preen? On starting up it just has your name and the OS?
 Many Thanks
 J

If you don't see "24 bits DAC" then it uses the 2 * 12bits DAC which have more noise.
Open it and check the PCB version. Only R6 use the 24 bits DACs.
Don't use your preenfm2 to make clear sin sound, add a little modulation to make the spectrum richer and the sound will be fine.