Hi Buddy
It have now been a few days whit my isl pro from my pf to the DAC.
First thing is it is more organic and have more flow in the music.
For the price maybe the best upgrade to a pf steamer there run whit a msb DAC.
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Food for thoughtā¦ this gentleman believes that more expensive, higher quality single-mode fiber systems (SFP modules x 2) will sound significantly better than ācheaperā AOC (multi-mode fiber integrated into two modules) due to lower jitter, lower noise, and lower latency.
Any worries about frictional damage to the metal-to-metal contacts can be partially mitigated by a super thin application of Caig ProGold, and I believe itās worth auditioning both the āoldā and the ānewā to hear whether thereās veracity to the claims. Would love to hear from everyone on their findings!
Couldnāt agree more - congratulations!
From our testing, AOC has outperformed the alternatives. The AOC system is more efficient and with the direct connection has lower power consumption. In a very low noise product like the Analog Converter, that is why we believe it performs so well.
For ethernet, it is a completely different animal though.
I would of course warn anyone reading his post to ignore and avoid the DAC cables. They will break the Cascade DAC. Happy hunting!
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Just changed to AOC between RF & DD 2 days ago, it is really better.
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Hereās the link on FSās website explaining the differences between Single mode vs Multimode fiber cable.
Takeaways:
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attenuation is lower in Single mode whose optical fiber core diameters are 9 um (OS2), vs multimode itās 50um (OM2/OM3/OM4)
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laser is used in Single mode, whereas low-cost light sources like LEDs and VCSELs are used in Multimode which leads to higher latency (and, important for audiophiles - potentially higher jitter and noise?)
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bandwidth is higher in Single mode
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color sheath of the optical fiber in Single mode (OS1/OS2) = yellow; Multimode (OM3) = aqua
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The AOC which has been popularized on this thread must have been by now purchased in the hundreds, if not in the thousands (at very affordable prices of less than US$200).
But please be mindful that AOCs were designed for āhigherā bandwidth at a LOWER COST, utilizing LEDs/VCSELs (instead of lasers), and thicker optical glass fiber cores. IMO, this introduces risks of lower waveform fidelity, higher photon dispersion, leading to higher jitter and hence more noise as the hardware engages error-correction computation more often.
How these specifications translate into the most important criteria of all, the SOUND of MSBās digital directors and analog converters, is still debatable. In my Cascade DAC based system the AOC module seems to have deleterious effects when used between two SOtM sNH-10G switches. Most notable was the reduction in both bass quality/quantity and imaging specificity.
Iām overseas right now, so Iām unable to report on my listening notes post-restoration of the Cascade DACās modules from the āupgradedā Multimode SFP+ aqua AOC back to the āoriginal/stockā Single mode SFP.
But in February, Iāll be able to do so. Please stay tuned!
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Apparently, the AOC does not have the technical weaknesses which I had guessed. The founder of Uptone Audio wrote the following on WBF, which Iāll quote.
ā You seem to imply that multi-mode fiber transceivers (as used captively on AOC or in an SFP module) do not use lasers. That would be incorrect as VCSELs are indeed lasers and LEDs are never used except in ancient 100Mbps transceivers.
Also, the BER (bit error rate) specifications for single-mode and multi-mode SFP/SFP+ transceivers are all the same (at 10 to the minus 12 power).
Lastly, there is no active error correction with these links. Some switches doing 40G, 100G, 200G and above do implement FEC (forward error correction), but such is never done with the PHYs/MACs of 1G/10G ports. And the BER specs for such present no challenge or need for extra correction beyond what Ethernet 8B/10B (1G) and 64B/66B (10G) coding takes care of.
All that said, there are other reasons why single-mode fiber and transceivers can be preferred and reveal audible differences. But I wonāt delve into those here in this thread.ā
Iām even more curious - why does Single-mode and Multi-mode fiber/transceivers sound different, and why might Single-mode sound better?
Hi QuadDiffuser
The physical, outside diameter of single and multimode cables are the same.
However the actual fiber that transmits the light in single mode cables is about 1/5th the diameter of the fiber in multimode cables. My guess is this leads to less jitter in single mode cables because the jitter effects of light ābouncingā off the walls of the fiber will be less in single mode than in multimode.
Another factor to consider is that AOC cables are tested in a complete form, with the SFPs already attached to each end.
However, fibers and the SFPs they are plugged into are tested as individual components and do not take into account slight variations in actual installations and the components themselves.
Just a guess though.
Dan
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Simply a fantastic example of product support. Makes me even more excited to be joining the MSB family.
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Hereās a useful link for those who want to dive deeper into SFPs.
These two Finistar SFPs are mentioned as being outstanding:
https://www.mouser.sg/ProductDetail/Coherent/FTLF1318P3BTL?qs=D%252B6gCNt%2Fg2C91cko4IuSEQ%3D%3D
https://www.mouser.sg/ProductDetail/Coherent/FTLX1475D3BTL?qs=Mv7BduZupUimdVCmqshw1g%3D%3D
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