The EtherREGEN thread for various network, cable, power experiences and experiments

[sandston]

Jud

I have the monoprice CAT8. I dissected one last night and the shields are indeed connected at both ends. The procedure was quiet simple. Razor blade off the plastic sleeve. Cut the shield wire to the metal housing. I then removed the metal housing because I wasnt confident I could keep the wires from touching the housing. This was done with a pair of needle nose starting at the seam in the metal housing. Bend it away at both ends and it pops right off. This did indeed leave a bit of a loose connector. However these cable are inexpensive enough that I was not too concerned. This weekend I will hot glue the ends to avoid stressing the solder points. Its not pretty but if you want to experiment its pretty straight forward. 

Common sense tells me to connect the unconnected shield end upstream. 

[sandston]

13 minutes ago, MarkS said:

I didn't get a chance to try the 10db attenuators on each end this weekend, but I will very soon.

 

Stupid question in advance.  Do the attentions just lower gain or volume by 10db?  If so, then aren’t the attenuators just volume knobs.  If not, then what do attenuators do?

 

 

This idea of attenuation of the fiber signal has lead me to do some research. I remember reading somewhere that there might be a minimum fiber optic cable length requirement in order to limit back reflections and I wanted to confirm this. Have not found any info to support this yet however I did see a guide that says you should put all attenuation on the receiving end only. 

https://community.fs.com/blog/guideline-for-fixed-fiber-optic-attenuator.html

 

There is also quiet a bit of info on how the attenuation is done and what this does to signal loss and signal distortion.

 

Perhaps a new thread needs to be started to compile this info. As we all know this equipment is designed for very long runs and we are using it for very short runs. We need to compile some numbers for the common transceivers and receivers we as a community are using including their output and input specs to determine how much attenuation we really need in a given run to be at an optimum operating point. 

[sandston]

I found a page that mentions non-optimum attenuation as well as the idea that some cables have the attenuation built in.

 

1. Fixed Attenuators: Fixed optical attenuators used in fiber optic systems may use a variety of principles for their functioning. Preferred attenuators use either doped fibers, or misaligned splices, or total power since both of these are reliable and inexpensive.

 

Inline style attenuators are incorporated into patch cables. The alternative build out style attenuator is a small male-female adapter that can be added onto other cables.

Non-preferred attenuators often use gap loss or reflective principles. Such devices can be sensitive to modal distribution, wavelength, contamination, vibration, temperature, damage due to power bursts, may cause back reflections, may cause signal dispersion etc.

[sandston]

For midprice power supplies the two most interesting current offerings to me look like Afterdarks LPS which appears to be a modified Chinese offering. It offers a lot of bang for the buck and I think this community will agree (maybe!) that AD seems to know what they are on about. $233 offered in multiple voltages. They also have a high current model in the $500 range.

 

https://www.adark.co/products/afterdark-black-modernize-15v-lps-x-cybershalf-ocxo-10m-edition

 

The other interesting midpriced power supply if IFI's new iPower Elite model. $299 multiple voltages. Very curious if anyone has put this on on a bench. This is a switching supply not a LPS however the output numbers sound impressive. I'm curious if the supply injects noise back into the mains like other SMPS supplies as is widely reported on this site. If they have somehow managed to control this as well this could be worthy contender. Surprised there hasn't been more discussion about this power supply here. I wish I knew more about how to test these things.

 

https://www.amazon.com/iFi-iPower-Elite-Supply-Adapter/dp/B08S5T4DNY?th=1

[sandston]

John are you commenting on the Ifi Elite? The Elite had high leakage current or the older wall wart versions?

[sandston]

First thank you John S for sharing your experience with IFI's earlier power supplies. Your knowledge on this subject is second to few if any! I wanted to report back here on the IFI Elite SMPS power supply. I hope this is of interest to some. As much as I would love to put Farad power supplies on all of my gear its just too expensive of a proposition. Currently I am looking at mid priced power supplies for my ethernet switch and router and came across the IFI Elite. Research tells us that IFIs previous power supply attempts have not performed well with regard to leakage put I am sure the team at IFI is reading these posts. I decided to pose the leakage current question to there technical team and wanted to share the response I got. I am no expert in this realm but like most of you rabidly glean from those of you on this site that are. Thank you all for this. Please go easy on me if my question wasn't worded technically correct. I think it may be an interesting supply worth further scrutiny. Have I not read somewhere on AS that some networking devices have issues with Linear Power Supplies? I wish I had the knowledge to test these things myself. Curious if the community has any more poignant questions I should pose to IFI?

 

Issue Details
Your Elite power supply looks very interesting. I am curious if IFI has done anything to address leakage current typically found in SMPS style power supplies. While output noise is the most important factor leakage current has become an important factor in the audiophile community when determining the quality of a power supply. As I understand it leakage current can effect the sensitive clocks that are the core of our digital audio systems. This, as I understand it, is why linear power supplies are preferred over SMPS style supplies. SMPS supplies tend also to dump noise back onto the AC mains where they can effect other gear plugged into the same circuit. I have read that previous ifi power supplies have not tested well in this regard. Has IFI addressed this issue with the Elite? If so the Elite stands to be a a power supply that the audio world should take better notice of. I am sure the community would love to hear more on this front. I know I certainly would. Thank You

 

 

Colin

20 January 2022 5:34 pm

Hi Stephen,

thankyou for enquiring about the iPower Elite 12v.

As the secondary is earthed to the mains on the negative lead, any leakage from the primary is shunted to earth. The input includes an EMI filter to reduce noise being reflected back into the mains. Clock systems are generally built to withstand some variation in the main power supply and so have their own RF filtering and regulation on their power supplies. Lower noise at audio frequencies on the main power supply generally has an impact on linear circuits such as the amplifier stage. Balanced design in iFi products allows the design to naturally resist power supply fluctuations.

Kind Regards,

Colin,

AMR-iFi Technician.

 

[sandston]

I have to apologize as I am realizing this may not be the right thread for my post regarding the IFI as my interest in it is for my network devices upstream from my ER. That's not to say it may work nicely as a mid-priced alternative to the stock supply. Please let me know if I should take this elsewhere.