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There seems to be incorrect procedure when measuring passive attenuators at ASR.
In the recent review here :https://www.audiosciencereview.com/...s/schiit-freya-s-preamplifier-review-2.11543/
we see " It performed really well in passive mode, providing fully transparency to my ultra low distortion and and noise audio analyzer"
In truth there really was no test at all, of the passive attenuator, because the unit was arranged to have maximum volume - and therefore we can presume all that was being measured was the units internal wiring, as there was effectively a short circuit from input to output. No wonder it measured well.
Suggestions for future passive measurement
Passives need I suggest to be measured, from where audio first becomes apparent and suggested then at 5 different incremental settings upward. We would then see in the presumed ethos of the forum, "audio science" the effect resistance and possibly where present contact distortion, or other distortions are occurring; https://www.pinkfishmedia.net/forum/threads/alps-potentiometers-gain-and-distortion.68076/ and digital variants https://www.diyaudio.com/forums/analog-line-level/227693-digitally-controlled-pot-distortion.html
RMS levels
Secondly the RMS voltage level ASR uses is unrealistic IMO to what any known CD contains with level. This then can change the need of objective assessment to be awkwardly distanced from what we hear. Rather 4V RMS may be the potential a analog output can swing into a given load, .... but the actual CD itself, I would argue can never deliver this figure.
Audacity -lets check some CD's
Readers can with minimal expense and I hope will indeed prove this to themselves, by installing Audacity then allowing that programme to reveal the RMS level shown as an example in the image. The image is a flac file of vangelis 1492 track 12, loaded into audacity.
The figure of measurement being input with a passive should by all means attain the maximum as the last of 5 volume measurements - but the maximum should be related to the present industry standard applying to the level applied when digitising of a recording occurs, which as I see is usually one in the same as the recording, unless specifically level adjusted by the artist during mastering. We can see this for ourselves using audacity. https://www.audacityteam.org
Questions arise like is CD level and streaming level the same ?
Lets check Audacitys scale system first
However firstly we need to assess how close audacity is itself to being correct with its scale shown as 1.0 ,0.5 ,0.0 and the same in the lower side direction to reveal a AC signal. Audacity does not state the scale to be voltage - but by all accounts it is exceedingly close, in this case as a
measure of 2v , being 1v positive and 1v negative checks, with a AC volt meter measuring to be the same.
If we apply levels which are used every day that we listen to , we then get closer to aligning objective vs subjective assessment as being the same.
In the recent review here :https://www.audiosciencereview.com/...s/schiit-freya-s-preamplifier-review-2.11543/
we see " It performed really well in passive mode, providing fully transparency to my ultra low distortion and and noise audio analyzer"
In truth there really was no test at all, of the passive attenuator, because the unit was arranged to have maximum volume - and therefore we can presume all that was being measured was the units internal wiring, as there was effectively a short circuit from input to output. No wonder it measured well.
Suggestions for future passive measurement
Passives need I suggest to be measured, from where audio first becomes apparent and suggested then at 5 different incremental settings upward. We would then see in the presumed ethos of the forum, "audio science" the effect resistance and possibly where present contact distortion, or other distortions are occurring; https://www.pinkfishmedia.net/forum/threads/alps-potentiometers-gain-and-distortion.68076/ and digital variants https://www.diyaudio.com/forums/analog-line-level/227693-digitally-controlled-pot-distortion.html
RMS levels
Secondly the RMS voltage level ASR uses is unrealistic IMO to what any known CD contains with level. This then can change the need of objective assessment to be awkwardly distanced from what we hear. Rather 4V RMS may be the potential a analog output can swing into a given load, .... but the actual CD itself, I would argue can never deliver this figure.
Audacity -lets check some CD's
Readers can with minimal expense and I hope will indeed prove this to themselves, by installing Audacity then allowing that programme to reveal the RMS level shown as an example in the image. The image is a flac file of vangelis 1492 track 12, loaded into audacity.
The figure of measurement being input with a passive should by all means attain the maximum as the last of 5 volume measurements - but the maximum should be related to the present industry standard applying to the level applied when digitising of a recording occurs, which as I see is usually one in the same as the recording, unless specifically level adjusted by the artist during mastering. We can see this for ourselves using audacity. https://www.audacityteam.org
Questions arise like is CD level and streaming level the same ?
Lets check Audacitys scale system first
However firstly we need to assess how close audacity is itself to being correct with its scale shown as 1.0 ,0.5 ,0.0 and the same in the lower side direction to reveal a AC signal. Audacity does not state the scale to be voltage - but by all accounts it is exceedingly close, in this case as a
measure of 2v , being 1v positive and 1v negative checks, with a AC volt meter measuring to be the same.
If we apply levels which are used every day that we listen to , we then get closer to aligning objective vs subjective assessment as being the same.
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