AudioCircle
Industry Circles => Bryston Limited => Topic started by: zoom25 on 30 Nov 2017, 06:14 am
-
This is based on the trials and experimentation in the past 3-4 months with various cables, power supplies, powerline adapters, network switches, and routers.
Here is the album with pictures and descriptions: https://imgur.com/a/2XIAV
I will be adding my thoughts regarding what worked, what didn't work, what sounded worst/bad/good/excellent, what made the most difference, and what made no difference. I will also offer thoughts on how the sound differs vs. local storage (flash drives and portable hard drives and hubs). I would love to hear from others on this subject.
Useful links and posts:
https://www.bicsi.org/pdf/conferences/winter/2009/presentations/Mythbusting%20Takes%20on%20Shielded%20Cabling%20-%20Herb%20Congdon%20and%20Brian%20Davis.pdf
https://www.siemon.com/us/standards/Screened_and_Shielded_Guide_7_Antenna_Myth.asp
https://www.siemon.com/us/standards/Screened_and_Shielded_Guide_9_Why_Use_Fully_Shielded_Cabling.asp
http://www.ti.com/lit/an/snla107a/snla107a.pdf
https://community.roonlabs.com/t/validity-of-audiophile-ethernet-cables/30251/25
-
https://en.wikipedia.org/wiki/Observer-expectancy_effect
:lol:
https://arstechnica.com/staff/2015/02/to-the-audiophile-this-10000-ethernet-cable-apparently-makes-sense/
:lol: x 100
-
https://en.wikipedia.org/wiki/Observer-expectancy_effect
:lol:
https://arstechnica.com/staff/2015/02/to-the-audiophile-this-10000-ethernet-cable-apparently-makes-sense/
:lol: x 100
Thanks CM! Excellent feedback as usual. :thumb:
It's funny that you didn't wait for me to even post my results and already assumed or hinted at what would be my results. You do this quite often. Hmmmm. Anyways, I wouldn't have it any other way. It would feel odd otherwise. Routine is a good thing. Maybe give this a read:
https://en.wikipedia.org/wiki/Psychological_projection :D
-
Ha ha, you're a good sport, I give you that much :thumb:
You had stated:
"I would love to hear from others on this subject."
With or without waiting for results.
So I chimed in.
Enjoy the musik.
pssst: The Ethernet cable has no effect on the SQ of a BDP-1. Simply put, the EN port and circuit inside BDP are electrically isolated from the rest of the digital circuitry, so....
(If they're not isolated, then shame on Bryston's engies... :duh:)
-
ETHERNET CABLES
First up, by popular choice ( :lol:), is ethernet cables.
Almost all of the Cat 5e, 6, and 6a were UTP. The only S/STP was the Cat 6a.
The setup was as follows: iMac w/Roon <----ethernet-----> Switch <-----ethernet-----> BDP-1
I would use the spare Linksys E3000 router initially to get these unmanaged switch working and connected to each other. Once the BDP-1 was recognized on the Mac, I would unplug the router and its power supply. No other devices were present on the switch. Only 2 ethernet cables at a time. No other switching power supplies besides the bare essential for the audio networking.
All the audio gear on Torus. The stock power supplies for the router and switch on separate strip outside the Torus. I kept the distance between all the gear and path of the cables constant.
The Cat 6a SSTP came with graphs and readouts as well. Each cable had the propagation delay (ns), delay skew (ns), resistance, and other performance characteristics measured individually.
Sound:
Used HD 800 and all Amphion monitors/amps/cables monitor setup.
Cat 5e and 6 UTP:
-All the Cat 5e UTP sounded the same.
- All the Cat 6 and 6a UTP sounded the same.
- The only tiny difference I felt at times between 5e UTP and 6 UTP was that the cat 6 had a tiny bit better focus. Still, nothing compared to other tweaks.
- Sound tonality and presentation was the exact same.
Cat6a S/STP:
- These came with metal plugs on both ends.
- The BDP-1 has shielded ports.
- With the DGS-1005 (unshielded) and DGS-108 (shielded), I could try connections where the grounds would be attached on both ends or only one end.
- In a home environment, I could not ground the DGS-108 switch
- Eventually, I even took out the metal shields on both ends, which allows me to verify whether what I was hearing was due to any differences between the switches and their power supplies.
- I would NOT recommend having the grounds connected on both ends when both devices have shielded ports.
- In general, I would not recommend having the ground connected on the BDP-1 end.
- I eventually had the ground disconnected on both ends.
- I did find that the Cat 6a S/STP had the blackest background among the bunch and this stayed regardless of whether the grounds were connected or not on one or both sides.
- When you have one or both the grounds connected, there is a specific characteristic change to the sound.
- I felt this character was really exemplified when grounds were connected on both ends.
- The transients were oversmoothed and this was noticeable on material with a lot of drums and kicks.
- I compared my 5e UTP, 6 and 6a SSTP with the ground lifted to the ground connected 6a cables. The former all presented drums and kicks with clean rise and decay. They all sounded correct this way.
- With the ground connected, the drums didn't have the proper energy and bite.
- There were other changes I noticed and to some they may or may not like it.
- I just knew that the sound wasn't correct and so ditched the shields on both end. Better this way for me.
- With the shield disconnected on both end on both pair of Cat6a S/STP, this is where I found the sound was the best.
- Clean transients and correct sound like the rest of the UTP, but with better clarity and focus to the image and a black background.
- There can be a number of reasons for why there might be a difference.
- The Cat 6a S/STP not only eliminates pair to pair crosstalk, but is also better suited EMI/RFI wise in an audio environment in rejecting or radiating noise.
- This can reduce interactions with other nearby cables and gear.
Two useful links:
https://www.siemon.com/us/standards/Screened_and_Shielded_Guide_9_Why_Use_Fully_Shielded_Cabling.asp
https://www.siemon.com/us/standards/Screened_and_Shielded_Guide_7_Antenna_Myth.asp
TL; DR:
- If going with UTP, go with Cat 6 and forget about it.
- No sound difference between any of the Cat 5e and Cat 6 UTP cables.
- For best sound, go with a S/STP design, but make sure that the grounds are not connected.
- Introducing the ground can change the sound in a very specific manner (softened transients, over smoothed sound)
- Shield and screened cables can potentially offer a very quiet background, and better clarity. You can read up on the phase performance of both the HD 800 and Amphion monitors.
- YMMV based on your environment and setup.
-
Link to the Cat 6a S/STP: http://www.infinitecables.com/cat5e-cat6-cat6a/cat6a-molded-shielded-patch-cables/cat6a-sstp-black/
The Cat5e and 6 was all the stuff I had gotten from a data centre for free. Everything was generic, cheap, and measured well.
-
Ha ha, you're a good sport, I give you that much :thumb:
You had stated:
"I would love to hear from others on this subject."
With or without waiting for results.
So I chimed in.
Enjoy the musik.
pssst: The Ethernet cable has no effect on the SQ of a BDP-1. Simply put, the EN port and circuit inside BDP are electrically isolated from the rest of the digital circuitry, so....
(If they're not isolated, then shame on Bryston's engies... :duh:)
With the cables and power supplies, I'm not even going to attempt to say that this particular thing improved or changed the sound for this particular reason. On my end, I tried to keep things to a minimum and change one thing at a time. However, because of the interactions between all the gear and components, there is simply no way I can say anything with full conviction of "this is exactly why X happens". It would be arrogant to do so.
There is already quite a bit of discussion on other forums from developers and manufacturers that are far more talented about what might be happening in an isolated case or a system.
At best, I can only offer suggestions based on the repeated patterns that I observed over the last 4 months while changing things one at a time.
-
Powerline Adapters
The D-Link AV500.
These can deliver consistent performance in terms of speed. I still found my wireless faster.
These devices are simply way too noisy in how much noise they put out on the mains as well as radiate. When connected to the BDP-1 directly, the sound was at its worst. Dynamically flat and unengaging. BDP-1 sounded worse than my iMac as a source.
Additionally, on my MacBook Pro running off of battery (no power bar connected), with headphones plugged into the headphone jack, I could hear the buzzing noise interference. Again, no electrical connection in this case.
NOT RECOMMENDED. There is simply too much baggage to deal with this.
-
I did notice that when putting in the various Cat5e of 5-10 feet, it could sometimes take anywhere up to 5-10 seconds. The Cat 6 was faster. The Cat 6a SSTP was near instantaneous.
Let me guess: you tested these cables in the same order? So, with the Cat5e, the associated MAC address and IP address are not cached in the router and Roon server, so look-ups took a little more time. When you tested the follow-on cables, physical and logical network addresses are already cached and look-ups are instantaneous.
Trust me: at 5-10 feet, there would be no measurable difference in network transmission latency or throughput.
-
Power supplies for the switches:
Relevant reading from Texas Instrument: http://www.ti.com/lit/an/snla107a/snla107a.pdf
Switches used: D-Link DGS-108 and DGS-1005.
Biggest problem with the supplied power supplies on these switches is that they are not grounded.
These stock switching power supplies radiate a lot of EMI which I confirmed with an AM radio. You could even hear their noise pattern change as the load varied. So, that alone can impact other gear nearby at some level.
I tried the 5V Apple charger as well which worked fine. Then I added the Jitterbug to the Apple charger. I did not like it there. It cleaned up some things, but added this fatigue that would hurt my ears. Same thing I experienced when I used the Jitterbug with the portable hard drives connected to BDP-1 directly without a hub. The Jitterbug doesn't seem to like being in the middle of things being actively powered.
When I went back to the stock switching D-Link, everything worked fine and sounded right. The piercing effect was gone.
Then came the Teradak U9 linear power supply which is grounded. This was by far the biggest improvement in comparison to cable changes or adding Jitterbugs or other generic switching power supplies. I use the 5V usb output which is reported to be cleaner than its DC output. There are noise measurements scattered in the wild.
John Swenson has some good info on this subject as well. Grounded power supplies seems to be the one thing that every one out there agrees on.
The Teradak U9 is not only grounded but is also better at not putting noise back into the mains or putting airborne noise.
I haven't yet tried plugging the Jitterbug into the Teradak, even though it's pictured there in the album as a thing I may try in the future.
The Teradak brought a change that I think almost anyone could identify. It was not subtle. Among all the tweaks listed on this thread and in the past regarding local playback with various flash/portable drives and USB hub, this would be my #1.
TL;DR: Teradak U9 LPS for the network switch brings the most improvement. First thing I would recommend.
-
Let me guess: you tested these cables in the same order? So, with the Cat5e, the associated MAC address and IP address are not cached in the router and Roon server, so look-ups took a little more time. When you tested the follow-on cables, physical and logical network addresses are already cached and look-ups are instantaneous.
Trust me: at 5-10 feet, there would be no measurable difference in network transmission latency or throughput.
I've tried them in all kinds of order just by sheer chance over the months. Sometimes, the switches and router were left powered on during the swapping. Other times, the switches was also powered off while swapping. Regardless of the situation, I still found the Cat6 SSTP to lock on almost instantly.
You are most probably correct and it could be exactly that. For my purpose, there was zero difference after the initial setup.
-
I think that's about all I have to say on this topic. On the other older thread, I've already exhausted my views on local attached playback. The only thing left is the Wifi Dongle and how wireless compares. I may consider that if I move my setup somewhere else.
Roon through this setup sounds considerably different to how I experienced Roon last year or even the start of the summer this year. I don't find whatsoever like in the past that Roon is lacking to MPD local playback. I'm perfectly happy with the sound coming out of the Bryston and my headphones/speakers.
No more tweaking for awhile. Looking forward to hearing the Audeze LCD-2C again. :thumb:
-
I've done a bit of experimenting with routers, switches, cables and isolators. Here is what I discovered:
1) if you are using wired Ethernet, the most important thing you can do is tie the DC common of your router or switch to earth ground. This will significantly reduce the "leakage" noise that comes through the Ethernet transformer. you can do this with a LPS or a switcher/wall-wart. A bit of a kludge with a wall-wart though.
2) change the power supply on router or switch that is driving your Ethernet interface to a fast-responding LPS. I have heard good things from other customers about the Sbooster products for this purpose, although they probably don't have #1. You will need to run a separate wire.
3) add a good isolator in the Ethernet cable. I have found that a .5m cable from the router to the isolator and then a 1-3 meter cable from isolator to the DAC input works good. I like the EMO EN-70e. Inexpensive too.
4) Change your cables to a reputable CAT7 type. I like the TNP brand from Amazon. Cat6S is also an option.
Steve N.
Empirical Audio
-
1. Used UnShielded cabling. UTP is noise immune to 30 mega hertz.
2. CAT 5e is good for 10GBe, and is supported, by a number of manufactures for 45 meters. This should put into perspective how over kill a 15 year old Ethernet standard is for audio data rates (it's awesome :) )
3. A switch/router Achilles heal is the single ended power supply. High end switches and routers are often have a dedicated DC power port. Data centers often run DC to the entire rack line.
I took a 315 foot generic CAT5e at $0.30 a foot and a 3 foot Nordost Heimdall II at $233 a foot. When blinding and going NAS(Netgear DS)<>Switch (Cisco SG 200-8)<>Cary Audio DMS 500<>Amp<>Speakers. No one could hear the difference.
The best way to do this testing, and it's what I did, was to place switch ports into a LAG and hang multiple cables off the switch and swap them at will. I don't understand why a CAT6 would bring up the interface on the Bryston any quicker than any other compliant cable. That's never been my experience.
Me personally? I like wireless for a myriad of sound (pun intended) technical reasons. For $80 I have dedicated AP on it's own channel and SSID the I routinely get 38MB/S throughput on. That's 38 time more bandwidth than needed for 24/192 PCM.
-
Let me guess: you tested these cables in the same order? So, with the Cat5e, the associated MAC address and IP address are not cached in the router and Roon server, so look-ups took a little more time. When you tested the follow-on cables, physical and logical network addresses are already cached and look-ups are instantaneous.
Trust me: at 5-10 feet, there would be no measurable difference in network transmission latency or throughput.
I have to agree with you there. Putting my multi homed machine (4 Intel NIC ports) into an LACP team and creating a dynamic LAG on the switch allowed cable swapping regardless of 5e or 6 or 6a to bring the interfaces backup in the same amount of time.
-
Yeah, I have no idea why Roon/BDP was being weird with responsive time with different cables. Not an issue. I'm leaving my cabling as is.
Before I was wondering if the Teradak LPS would be fine for audio uses as it was around $50. There are more expensive options out there, but I didn't want to spend anything serious on a power supply for a switch. So I was hoping for something that would get the job done or gets close. The experience was better than expected from the first moment. The soundstage depth, width, layering, and imaging just melted. Even on headphones, you can notice the difference from before. The other thing I noticed in comparison was that before it felt like there was this weird built up energy in the system. It just flows better now.
In comparison to MPD, there is less grain (hash?) which adds to the liquid aspect. I suspect it may be due to the USB drives (with or without hubs?) injecting noise. Perhaps, using MPD with a NAS might mitigate this. That actually might be a more fair way to compare MPD against Roon/RAAT, as both are getting data over ethernet. In that case, I suspect there would still be more happening inside the BDP-1 with MPD and processing vs. the incoming PCM from Roon.
-
...
Perhaps, using MPD with a NAS might mitigate this. That actually might be a more fair way to compare MPD against Roon/RAAT, as both are getting data over ethernet. In that case, I suspect there would still be more happening inside the BDP-1 with MPD and processing vs. the incoming PCM from Roon.
It's actually the opposite, if I recall correctly from previous measurements (and on an older version of the RAAT app).
The Roon endpoint is constantly communicating back to the Roon Core/Server, in addition to processing PCM -> ALSA. That's why your network connection is so important. With NAS, you are mostly just pulling data down into the BDP, but with Roon there is traffic going both directions.
-
It's actually the opposite, if I recall correctly from previous measurements (and on an older version of the RAAT app).
The Roon endpoint is constantly communicating back to the Roon Core/Server, in addition to processing PCM -> ALSA. That's why your network connection is so important. With NAS, you are mostly just pulling data down into the BDP, but with Roon there is traffic going both directions.
Hmmm, interesting. The CPU currently lingers in at 11%. Although, I'm not sure how much that number translates to or what kind of noise each component (RAM, CPU) is generating, so it may be useless as a factor determining SQ. Best to probably listen.
-
It's actually the opposite, if I recall correctly from previous measurements (and on an older version of the RAAT app).
The Roon endpoint is constantly communicating back to the Roon Core/Server, in addition to processing PCM -> ALSA. That's why your network connection is so important. With NAS, you are mostly just pulling data down into the BDP, but with Roon there is traffic going both directions.
I haven't spun up my protocol analyzer to map out Roons protocol but I'm with you on it's chatty nature.
If playing straight up through Tidal I can pull the Ethernet cable and the entire track plays. If I spin up Tidal via Roon soon as you pull the plug your done in a matter of seconds.
Not sure what's going on there but the behavior has me scratching my head at how sub-optimal it is. Suffice it to say I don't use Roon.
-
Hmmm, interesting. The CPU currently lingers in at 11%. Although, I'm not sure how much that number translates to or what kind of noise each component (RAM, CPU) is generating, so it may be useless as a factor determining SQ. Best to probably listen.
The computer is constantly making noise. I had an internal PCIe EMU 1212M Pro-Audio card. I took the balanced cable (TRS <> XLR) and on the XLR (input to the amp) I floated the shield drain conductor.
You could hear mouse movement, button click, keyboard, HDD access (SSD you could still hear but lower in volume and shorter in duration), paging operations. Soon as I soldered up the drain wire: Pristine audio.
It's the DAC's job to reject all of this. If what is going on in your computer is affecting your DAC you most likely have a defective DAC, or less likely defective cabling or computer.
-
The computer is constantly making noise. I had an internal PCIe EMU 1212M Pro-Audio card. I took the balanced cable (TRS <> XLR) and on the XLR (input to the amp) I floated the shield drain conductor.
You could hear mouse movement, button click, keyboard, HDD access (SSD you could still hear but lower in volume and shorter in duration), paging operations. Soon as I soldered up the drain wire: Pristine audio.
It's the DAC's job to reject all of this. If what is going on in your computer is affecting your DAC you most likely have a defective DAC, or less likely defective cabling or computer.
I've never encountered these problems with my DAC. Although, it does benefit being fed from better sources. Most DACs, including Bryston's own BDA benefits from the BDP. Does that make the BDA defective?
-
I've never encountered these problems with my DAC. Although, it does benefit being fed from better sources. Most DACs, including Bryston's own BDA benefits from the BDP. Does that make the BDA defective?
Remember I purposefully midwifed a cable to show this...
Then you have a DAC designed by a competent engineer. What's 'better sources'? I don't know if feeding a good component crap would make it a crap component. It's trivial to feed it cleanly.
My Emotiva DC-1 seems rather immune to what modern, decent computer, is feeding it. Right now that would be an Intel J3455 based machine with a medical grade 12V LRPS. The Emotiva has it's own optimized LRPS and doesn't rely on bus power.
-
Remember I purposefully midwifed a cable to show this...
Then you have a DAC designed by a competent engineer. What's 'better sources'? I don't know if feeding a good component crap would make it a crap component. It's trivial to feed it cleanly.
My Emotiva DC-1 seems rather immune to what modern, decent computer, is feeding it. Right now that would be an Intel J3455 based machine with a medical grade 12V LRPS. The Emotiva has it's own optimized LRPS and doesn't rely on bus power.
I use a Dangerous Music Source, which is engineered by Chris Muth, just like the rest of the Dangerous Music products that are made for mastering. The DAC is powered by a Teradak 12V13A LPS.
I also have an Emotiva DC-1. I did find that the USB connection from my Macbook Pro to DC-1 benefitted from an Audioquest Jitterbug. Same goes for Dangerous Source. I've never had problems with either as far as obvious noise or any problems.
However, I don't do my testing on the DC-1 as its relegated for my mid-fi TV rig with Mackie HR 824 Mk1's. Over the years, I've periodically tested the DC-1 against the Dangerous Source, but it never comes close. The Source is entirely on another level sound wise.
You are correct, I don't find much benefit or difference in feeding different sources to the DC-1, but then again it doesn't have that resolution in the first place.
https://cdn.head-fi.org/a/6222712.jpg
-
When I benched the DC-1 against a Bel Canto the DC-1 held it's own. The DC-1 is simply transparent and it's my preference. I wouldn't even begin to describe it as not a high resolving piece of gear.
Also A/B to some Wadia and both pieces were exemplar.
-
When I benched the DC-1 against a Bel Canto the DC-1 held it's own. The DC-1 is simply transparent and it's my preference. I wouldn't even begin to describe it as not a high resolving piece of gear.
Also A/B to some Wadia and both pieces were exemplar.
Enjoy the DC-1. :thumb:
-
Enjoy the DC-1. :thumb:
I do. I'll try the Dangerous as I think I have a friend that has one in his mastering rig.
Here's the koolthang with USB devices: You can get stereomix installed in Windows and drive multiple USB sound devices at the same time so instant A/B using the same audio stream is quite possible.
I don't doubt the Dangerous Source is a good piece but I've simply yet to find anything that walks away from what the DC-1 is capable of.
-
I do. I'll try the Dangerous as I think I have a friend that has one in his mastering rig.
Here's the koolthang with USB devices: You can get stereomix installed in Windows and drive multiple USB sound devices at the same time so instant A/B using the same audio stream is quite possible.
I don't doubt the Dangerous Source is a good piece but I've simply yet to find anything that walks away from what the DC-1 is capable of.
I've done similar syncing on Roon. You can listen to the same DAC with either a direct USB connection or from a network device and have it in sync for A/B toggling with a touch of a button. Additionally, with the BDP-1, I can feed AES to one DAC and the coax/BNC to another. Lots of ways to do comparisons depending on the purpose.
The Dangerous Source requires a 12V 2A power supply. I've used it with a stock switching wall wart and found the oversized 13A power supply better. A couple of people that now have the Teradak 12V13A previously had other linear power supply from Keces (DC-116) and Teddy Pardo and found that particular Teradak better. I leave all my gear on 24/7 plugged into the Torus which makes a pleasant difference.
Similarly, Michal of Mytek also shares the same feeling on having an oversized power supply. The Brooklyn has a built in power supply as well as the option for it to be powered with an external power supply.
https://www.gearslutz.com/board/12115436-post53.html
https://www.gearslutz.com/board/12115439-post54.html
-
Given the meager power requirements driving the DS with a regulated battery supply seems easy.
-
UPDATE:
In the last week, I made some changes to make things easier for better testing environment. I moved all the network gear and their power supplies at least 10 feet away from the audio rack to keep EMI out of the picture. From there I only ran one single ethernet cable that would plug into the BDP-1. This is the only ethernet cable that was in the vicinity of the audio rack. All power cables are shielded 14 AWG going into the Torus. The other cable in that area is the Grimm TPR for both analog and digital (AES) use. 3 feet of TPR in each cable.
The final switch is powered by Teradak LPS. The switch is DGS-1005 which is unshielded, so there cannot be ground loops regardless. Remember, BDP-1's ethernet port is shielded.
I tried 3 ethernet cables of the same length:
1) Cat 6 UTP
2) Cat 6a SSTP (grounds lifted on both side)
3) Cat 6a SSTP (ground connected to BDP-1)
________
The UTP had some grain to the sound with a slightly warm sound and felt the loudest. On the same track, I was comfortable at 9o clock.
With the #2 option of floating ground on both side, I think it was slightly quieter than the UTP. So, each time I felt I had to turn the volume up to 9:30 ish on the pot. It was a tiny bit more neutral sounding, a bit less grain, but still nothing that would be appreciable to most.
With the #3 option of ground connected on one side, the sound was distinctly different. Grain/hash in vocals was completely gone. In fact, it almost felt too smooth at first. I also had to turn the volume up on both the headphone amp (Audeze LCD-2C) and the speakers to 11:00. The soundstage became more fluid on the Audeze in particular.
I absolutely had to turn the volume up quite a bit to get the music going. However, as I continued to turn the volume up I never noticed any stress. I had to do a double take on the volume level. I'm never at these volume ranges with that music.
__________
How big is the difference?
Between #1 and #2, I think some listeners might be able to pick up some differences, but I doubt anything would come out in a blind test. However, if you put up #1, or even #2 against #3, I think a lot of listeners here would be able to pass a blind test. It's THAT noticeable. That smoothness in the vocals will be a dead giveaway each time!
__________
I remember reading that you should not have the switch near the audio rack as the cable leading up to it will still be producing noise. It's best to keep all the network gear and power supplies far away from the gear and only have the one cable going into the audio rack.
__________
Siemons:
https://www.siemon.com/us/standards/Screened_and_Shielded_Guide_9_Why_Use_Fully_Shielded_Cabling.asp
https://www.siemon.com/us/standards/Screened_and_Shielded_Guide_7_Antenna_Myth.asp
The fact is that both screens and shields and the copper balanced twisted-pairs in a UTP cable will behave as an antenna to some degree. The difference is that, as demonstrated by the simplified loop antenna model, the noise that couples onto the screen or shield is actually 100 to 1,000 times smaller in magnitude than the noise that is coupled onto an unshielded twisted-pair in the same environment.
As shown in figure 7, the coupling between two UTP cables (shown in black) is a minimum of 40 dB worse than the interaction between two properly grounded F/UTP cables (shown in blue). It should be noted that 40 dB of margin corresponds to 100 times less voltage coupling, thus confirming the modeled predictions. Clearly, the UTP cable is radiating and receiving (i.e. behaving like an antenna) substantially more than the F/UTP cable!
______________
Very happy with the BDP-1 this way. Right now, it truly sounds and justifies its price. It has to be heard this way.
This is how I'd recommend reviewers to hear the BDP's at their best. I've done the simple and isolated flash drive connection with MPD and it doesn't compare.
I think I might be done with copper ethernet tweaking. Simple rules, some inexpensive upgrades to cables and power supplies and a lot of space between them. :thumb:
-
The noise floor has definitely gone down. Whether, it's less crap going in or less crap going out or both, I am not sure. Low level resolution in particular.
2 instances in the last 24 hours where I heard or noticed something in tracks that I've heard at least 50 or more times. One of them was during a skit portion of a hip hop song where I actually made out the instrument being plucked in the background on a TV that was playing. I had to stop and go back and verify as I had never heard that detail before.
The other case was on a A.R. Rahman track where I had never heard the very faint noise floor during the start of the track and some intermodulation distortion during the silent parts of the track.
Preferences aside, if I'm noticing things that I haven't noticed before, then there must be something going right. The A.R. Rahman stuff reminds me very much of how things sounded back when I used to listen on tape. Very smooth and grain free. You could easily fool a vinyl enthusiast with this.