FIR Phase Filters

[mfb]

Can someone point me to a spot that has the descriptions of each of the FIR filters?

Thx

[aswiss]

It’s try and decide - no documentation.

[AZWink]

My Oppo UDP-205 has same DAC and filters as the RS150. They only list the different filters with no description of each. So yes, try and decide…

[mfb]

Thanks for the feedback. Currently using min phase with slow roll off. I’ll plan on evaluating the other options.

[arturox2]

HiFi Rose should address this and other items in a detailed owners manual!!

[HBL]

• The filter is the final step of converting PCM digital audio to analogue.
• It removes the jagged stair step pattern, restoring the waveform to a near perfect representation of the original analogue signal.
• There are several filter designs which can have an effect.
• One parameter of filter design is “Fast” or “Sharp” on the one hand, and “Slow” or “Smooth” on the other
• Fast/Sharp filters generally have the flattest, most extended treble response, yet are generally also the best at suppressing ultrasonic images from the final signal.
• Slow/Smooth filters generally have a high frequency response that starts rolling off earlier than Fast/Sharp, although around 20kHz (for CD-quality audio) the Fast/Sharp filters generally take over to greater effect.
• Slow/Smooth filters generally show less so-called ringing than Fast/Sharp when impulses are examined in an oscilloscope, but some do exhibit ultrasonic artefacts.
• Another parameter is “Linear Phase” compared to “Minimum Phase” or “Short Delay”. Where none of these three terms are mentioned, the parameter is most likely Linear Phase.
• Impulses delivered using Linear Phase filters tend to have the so-called ringing evenly distributed both before and after the impulse.
• Impulses delivered using Minimum Phase filters tend to have the so-called ringing all happening after them.
• Minimum Phase filters reduce latency – group delay in the signal. It is very useful in pro-audio applications.
• Linear Phase tends to be closer to the original input signal.
• Some DACs have variants with names like “Hybrid” or “Low Dispersion” which typically involve some compromise between Liner and Minimum Phase.
• Some DACs dispense with the filter entirely. These have various names, some of which disguise their character, but often they are called non-oversampling, or NOS.
• Their outputs are characterised by a rather diminished top octave and a considerable level of ultrasonic artefacts.

[mfb]

Good stuff. It’s kinda funny. I’m swapping between options and depending on the content, sometimes I can’t tell any difference, maybe I can. I have a pretty high resolution system, but old ears…

[nachocom]

¿ en que menu del 150B esta la posibilidad de seleccionar un filtro u otro del DAC?
Gracias

[ROSEHAN]

Hello @nachocom

no sé español Lo explicaré con imágenes.

1. Por favor, haga clic en el área marcada en rojo
   

   

2. Por favor, haga clic en el área marcada en rojo
   

   

3. Por favor, haga clic en el área marcada en rojo
   

   

4. Seleccione la configuración deseada en el paso 1 y haga clic en Aplicar.
   

   

Thank you

[Maxxim]

Hi.
This synthesized, integrated story is a piece of work.
congratulations and thank you… many will find it useful.

Maxxim