Put my android on noise meter and logged 4 times 30 seconds house music lol it hurts but not as much as testtone lol.
PeakdB 86,0dB with coax, 86,9dB with twisted pair.
LAeq max 65,6 avr 64,6 dB with coax
LAeq max 66.2 avr 66.0 dB twisted pair
My phone also seems to detect a louder twisted pair. So louder because of lower capacitance ???
PeakdB 86,0dB with coax, 86,9dB with twisted pair.
LAeq max 65,6 avr 64,6 dB with coax
LAeq max 66.2 avr 66.0 dB twisted pair
My phone also seems to detect a louder twisted pair. So louder because of lower capacitance ???
Would be fun if the coax and twisted pair could be measured so any differences also vs. frequency could be revealed.
Soundwise the slightly louder one often is considered better/is preferred. But in my case I do not feel comfortable with unshielded cable from cdtransport to poweramp, dac=poweramp in my situation. I worry too much lol.
Also wonder if impedance is so much off now that it does matter even with only 0.9 meter
Also wonder if impedance is so much off now that it does matter even with only 0.9 meter
Do you suggest inaudible interference carries digital signal to higher level somehow? Would be funny, almost unphysical, but surely illogical. Recorded silence I listened to was barely audible with a hint more spike/static with twisted pair, can't hear noise with music.
Primare specifies this audio digital output as spdiff, nothing more.
But you keep looking in wrong direction I believe, almost religously believing spdiff cables never should make a difference, whatever form they take. Both transmitter and receiver are 100% closer to spec than this unshielded twisted pair ever can be.
Primare specifies this audio digital output as spdiff, nothing more.
But you keep looking in wrong direction I believe, almost religously believing spdiff cables never should make a difference, whatever form they take. Both transmitter and receiver are 100% closer to spec than this unshielded twisted pair ever can be.
The real difference can come when your system with wires plugged in is subject to even the most basic say conducted immunity test or similar.
On a different note, I wonder whether really high tech gear, say medical/aerospace or military stuff, the engineers worry about the dielectric becoming polarized, breaking the cables in etc...
On a different note, I wonder whether really high tech gear, say medical/aerospace or military stuff, the engineers worry about the dielectric becoming polarized, breaking the cables in etc...
DF96, Peak dB is higher, from cd hrough cable to powerdac->speakers and uncalibrated mic/app. 30 sec "music" 4 times, 1st coax, 2nd,3rd twisted pair, 4th time coax. Just sharing. Posted all details. I also listened to music, Brahms-Vengerov, Enya. AB repeat 15 seconds roughly, lower avr volume, probably dozen times, and coming from coax listening to twisted pair I felt it was louder, several times. Funny thing was I could not be sure about it being softer from twisted to coax. Somehow I can't tell volume going down a little(after short break). Difference is not huge, I am certain I can't hear it at this time of day/night.
Once again I read you say physics/maths/engenering tells you there can't be any difference between whatever cable used for spdiff (or at least short cables I described). does that also mean you can't hear a difference, whatever short cinch/rca you use for spdiff in your system (at home, using home-audio) or do you mean you just can't explain?
Once again I read you say physics/maths/engenering tells you there can't be any difference between whatever cable used for spdiff (or at least short cables I described). does that also mean you can't hear a difference, whatever short cinch/rca you use for spdiff in your system (at home, using home-audio) or do you mean you just can't explain?
No, what he said was that you can't get a level difference that way. Other differences are unlikely, but possible, manifesting as noise or pops/dropouts.
It's a straightforward extension of this that's the "answer". Vary the method of transmitting signals and the level and type of interference and noise that's introduced varies. This then intermodulates with the audio signal, especially with dynamic waveforms, ie. music. Not obvious distortion, but the low level, noise floor, quality of the waveform is altered, the spectrum of such if isolated from the 'pure' music signal will differ between the two connection types, and the powerful DSP mechanism in your head filters this out, and says, this replay sounds "different".
Good ol' pyschoacoustics then also climbs on board, meaning that the subjective impression of the loudness of one version versus the other will not be identical, because of that variation. Every objective measurement will show perfect equivalence, but inside your head what your hearing registers will be a contrary 'result' ...
Last edited:
SPDIF uses unbalanced 75ohm coaxial cable. Using anything other than this could at best make no difference, and at worst could cause data corruption (unlikely, as it would sound horrible so you would notice it) or increased jitter (likely, but audibility may vary). Increased jitter is unlikely to increase analogue signal level. However, the added distortion might create the perception of increased signal level.irribeo said:
Measuring the level of a changing music signal is very difficult. Estimating the level by hearing is even less reliable. I don't think there is anything I need to explain.
If someone told me he had just seen a unicorn I would not feel under too much pressure to 'explain' it, given that what he claims to have seen is known not to exist and explanations are trivial: alcohol or other recreational substances, fatigue, a practical joke etc.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.