The question is, could it be a small amount of distortion that makes the output at 6V sound “more colorful, more engaging,” more natural, more detailed with certain setups than at 2V. It could be, although, with the Cardas interconnects the bass is tight and the instruments are clearly delineated at 6V.
There is definitely distortion with the Oyaide interconnects at 6V and sometimes it makes vocals sound amazing and sometimes over the top but the bass is always boomy and the instruments lack clear delineation. At 2V things are under control, again, with the Oyaide.
The only thing close to objective measurements of distortion at 6V I could find is this review of the Rossini
Quote “Listening tests conducted years ago revealed that, to my ears, Rossini’s 6V output delivers the most colorful and engaging sound. But since some preamps and integrated amplifiers that arrived for review couldn’t handle 6V, I reluctantly switched to 2V. Then, while preparing the specs for this review, I noticed that specified residual noise levels are lowest at the 6V output. With this confirmation for my 6V preference, it’s now back to 6V.”
In essence the additional,distortion that your research indicates for the Rossini DAC is so minor as to be subjectively insignificant.
However applying an input signal which exceeds the rated input sensitivity of the amplifier increases the distortion of the amplifier. This is simply because the rated sensitivity describes an input signal resulting in the full rated amplifier output.
Although this both accords with theory and measurement it becomes harder to correlate to subjective experience. Additional distortion is not always judged as inferior. Imagine an amplifier with measured THD of 0.1% and another of 0.01%. Superficially it may be anticipated that the second amplifier with a lower figure will sound better. This is not necessarily so as the spectrum of the distortion harmonics ( not quoted) is significant. Further, subjective judgement of distortion can be misleading, If you care to find it, there is an amusing video onyoutube of a demonstration by that acme of test equipment, Audio Precision, deliberately adding distortion to a music signal and the audience finding that they can only sense any additional distortion when it reaches double figures.
So, if you like the sound then at the end of the day it’s your system and yours to do with as you like.
It’s still a bit intriguing that, at least in my case, it’s not the amp - I connected two - but the XLR interconnects that determine whether 2V or 6V output from the DAC sounds “better.”
If AES ( XLR) connectors sound different then it is not necessarily to do with different line output voltages. Different cables can sound unlike each other- sometimes even with two which are nominally the same models. So, are you hearing the result of a voltage change or is it just the cables ( or, I guess, both) ?
If you hear differences with the same cable and ONLY the line output voltage has been changed then that is the way you can attribute the effect to that factor subjectively. However, even when given this, other parameters can come into play including the input sensitivity of the receiving device and the effect this can exhibit . If you like one or the other that’s fine anyway of course but finding an unarguable reason requires a little rigour.
I asked Perplexity to summarize the main points of the “What makes 6v better than 2v” thread and I think I understand now why impedance matching between a DAC and an amp is important and why 6V can still sound better under certain circumstances with certain amps, the Lina being one of them IMO.
On the topic of interconnects, it could be that cables that have superior shielding, better copper, better speed etc. allow for a “better” signal transmission to the amp so that the signal remains above the noise floor at 6V output with less distortion. Because distortion is definitely not what I’m hearing with the Clear Beyonds, but I could be wrong.
I think you are mixing up a few things here Donald. “Speed” is not an electrical property afaik, I think you mean current, which is inversely related to impedance. Neither of these have anything to do with distortion or SNR.
Good to see someone is paying attention out there! Well, I am about to enter a scary new phase of my life with only one kidney.
Mrs Struts is armed to the teeth and on her way to New Zealand. I understand Ben has gone into hiding. I am just sitting here with my drip and a silly grin on my face!
Well since that would leave me kidneyless probably not for the foreseeable future. And given how divided opinion is here on the question of whether it sounds better with or without (there is a lovely saying in Swedish “people’s opinions, like their bottoms, are split down the middle”) I would want to audition it first.
In the case of the NHB-108, believe it or not, I wired my life savings half way across Europe without auditioning (I had done my research though, a guy on the dCS forum said it was awesome!) Demo units are a bit like Halley’s comet and are only observable here for a short period every 76 years…
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did you win the lottery?
Anyone have any suggestions? No, wait, I only have one kidney left… 
)
