Hi all.
I have an Hegel H190 that I use as roon endpoint, including its internal DAC.
For Tidal FLAC files i see this signal path, and was wondering if that downsampling phase is detrimental for SQ.
Does somebody know why it is happening at all?
According to Hegel no. They chose a very odd sample rate they believe their dac operates best at. Roon is doing the first step to convert to the best format for it to accept through its input. The 2nd is done inside the Hegel to 105.47. If you don’t use Roon this is all done via the amps digital circuit and you won’t see it as it’s hidden.
Whether or not it’s detrimental is down to you it’s a design choice of this amp.
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The Hegel is designed to use the CD group of sample rates which are 44.1 and multiples thereof. The AV group (48 and multiples) were clearly not catered for by Hegel. This wouldn’t ever be a big deal in any scenario but that which involves a third party (Roon) providing explicit information about what happens in the signal chain. You certainly are not compromising sound quality.
The notion of picking an unusual rate at which to operate is not new. My first foray in to the world of HiFi DACs was the Benchmark DAC 1. This accepted up to 192/24 but resampled everything to a weird rate which from memory was around 150k. This was published in the DAC specs.
As others have mentioned the part circled below is what the Hegel amp is doing. Roon is just reporting it.
As for does it sound bad or hurt SQ, that is for you to judge. If you think it sounds great, then its great!
The answer is, “probably not”. A straight conversion from 96 to 88 can introduce all kinds of weird aliasing artefacts, but roon avoid this by first scaling the audio up to a 64 bit resolution before performing any bitrate changes.
I doubt any of this is audible.
In his example, Roon isn’t doing it. The device us downsampling to 105.
Roon is dowsampling from 96 to 88.2 and the H190 is upsampling this to 105.47. I have the H120 (same DAC and streaming engine) and Roon sounds great through it. I’ve tried the same amp with external bit perfect DACs and couldn’t find any difference in sound.
In his example, he’s playing a 96k file, roon knows his device can’t play this and changes it to 64 bit float before converting to 88.
The device itself then converts to the weird number. Did you even look at the data flow? You can quite clearly see the parts roon is doing.
That’s right, and Hegel claim that the fact that Roon does part of the conversion is good because it takes that job away from the DAC.