1 (edited by nelson_a 2017-02-24 10:29:52)

Topic: Sample Rate Converter Quality of ADI-2 Pro vs Software-Based Solutions

Hello,

I've recently been going back and forth with some users on the GearSlutz forums, and it seems the consensus of most on the forums is that hardware-based sample rate converters are nowhere near the quality of offline / software-based sample rate converters.

Is this true (in general), or is the sample rate converter on the ADI-2 Pro equally as good as a high-end software-based sample rate converter?

I only ask as software-based sample rate converters are pretty cheap (some are even free).

As an example, the following site:

http://src.infinitewave.ca/

...lists sample-rate converter tests using various software-based sample rate converters.

They even tested out the Mytek STEREO192 SRC (a $1,200.00 dedicated hardware-based sample-rate converter), that comes nowhere near any of the high-end software-based sample rate converters.

I'm just a little confused by all of this; any help would be greatly appreciated.

Thank you,
Nelson

Re: Sample Rate Converter Quality of ADI-2 Pro vs Software-Based Solutions

Obviously depends on the specific implementation and also on what you need to do. Back in Live 7/8 days I needed to upsample a clip from 8 kHz. Live's SRC worked well enough for downsampling, but for upsampling that clip it failed hard. I then used the hardware SRC of my Creative X-Fi card, which worked well.

3

Re: Sample Rate Converter Quality of ADI-2 Pro vs Software-Based Solutions

The main difference to most of these software converters is that hardware works in real-time. And the manual clearly explains that the main reason for the SRC is clock-decoupling, not boutique upsampling (quite obvious as the SRC works only on the SPDIF/AES input).

So: You want to listen to the input signal right now, or transfer files back and forth and wait? You want to solve clock problems for real-time listening, or transfer files back and forth and wait? See...

Regards
Matthias Carstens
RME

Re: Sample Rate Converter Quality of ADI-2 Pro vs Software-Based Solutions

MC wrote:

The main difference to most of these software converters is that hardware works in real-time. And the manual clearly explains that the main reason for the SRC is clock-decoupling, not boutique upsampling (quite obvious as the SRC works only on the SPDIF/AES input).

So: You want to listen to the input signal right now, or transfer files back and forth and wait? You want to solve clock problems for real-time listening, or transfer files back and forth and wait? See...

Hello MC,

I understand.

That said, when you mention clock decoupling (as that is what I'm interested in using the ADI's SRC for), can I assume that the SPDIF/AES decoupled audio signal is still usable?

In other words, if the incoming SPDIF/AES audio signal to my ADI-2 Pro is locked at 44.1 Khz and I want to up-sample to 96 Khz (as my DAW session is at 96 Khz), is the incoming audio still good enough to be used in my audio production?

I'd assume the answer is yes, but when you mention that the SRC is only good for clock decoupling, is that inferring that really only the clock-rate (embedded within the SPDIF/AES) signal is really usable but not the audio (that's also embedded within the SPDIF/AES signal)?

Thank you,
Nelson

5

Re: Sample Rate Converter Quality of ADI-2 Pro vs Software-Based Solutions

nelson_a wrote:

when you mention that the SRC is only good for clock decoupling

Nowhere did I say so.

Regards
Matthias Carstens
RME

Re: Sample Rate Converter Quality of ADI-2 Pro vs Software-Based Solutions

MC wrote:
nelson_a wrote:

when you mention that the SRC is only good for clock decoupling

Nowhere did I say so.

Hello MC,

My apologies for misunderstanding you.

I only said that as you mentioned the following:

"And the manual clearly explains that the main reason for the SRC is clock-decoupling"

...I assume that if the manual made a point to state that the main reason for the SRC was to decouple, that playback / recording of up-sampled / down-sampled AES/SPDIF audio was of secondary (or less) importance.

Nelson

7

Re: Sample Rate Converter Quality of ADI-2 Pro vs Software-Based Solutions

And the manual also says:

The converter used in the ADI-2 Pro operates practically without loss of signal quality, so no audible artefacts or noise is added. In fact, the SRC works so well that we could recommend to just leave it on at all times, thus eliminating all clock problems right from the start. Which is the case for the SPDIF input in Auto mode.

Regards
Matthias Carstens
RME

Re: Sample Rate Converter Quality of ADI-2 Pro vs Software-Based Solutions

MC wrote:

And the manual also says:

The converter used in the ADI-2 Pro operates practically without loss of signal quality, so no audible artefacts or noise is added. In fact, the SRC works so well that we could recommend to just leave it on at all times, thus eliminating all clock problems right from the start. Which is the case for the SPDIF input in Auto mode.

Hello MC,

Thank you for clearing that up.

Nelson