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I've run my Wadia 861 with an NBS Signature II power cord for about a year now. Replacing the stock cord with the NBS made a slight improvement. Adding a dedicated power line for the Wadia made a larger improvement.Recently I had the chance to audition the Highwire Power Wraps. Since I had several available, I put one on the NBS cord, and gained a major improvement in sound-stage accuracy and tonal purity. Adding a second Wrap, so that the two meet at the center of the power cord, made almost as much improvement over the single Wrap as the single one made over no Wrap. Adding a third (again with the Wraps centered on the cord) improved things slightly over two Wraps. The larger size Wrap is required, and still makes a tight fit over the NBS cord. The smaller Wrap would fit easily over a stock cord, but the extra mass of the larger Wrap may make it more effective.
These $25 devices were designed primarily for non-detachable power cords on modest gear. It is surprising how much better my Wadia sounds with a couple of them on the NBS cord. Another way to look at this is to entertain the possibility that much of the controversy over the sound of Wadia 861X players has to do with deficiencies in the design of the power supply. It is possible for the supply to provide inadequate isolation from RFI on the power cord, to inject RFI on to the power cord, or both. Part of the issue with RFI on power cords is that the power cord looks like an antenna, and has a resonant frequency determined by its length and speed of propagation in its insulator. Even a little stimulus from, say, rectifier diodes, may set up a strong standing wave on the cord, like a little breeze can stimulate an organ pipe. If this standing wave corresponds to a frequency that can get past the power supply filters, it will affect the various circuits inside the player. The Power Wraps absorb RF energy and make it difficult for the standing wave to be sustained.
I don't know if other CD players would respond this well to the Power Wraps. I think it depends on the care and skill exercised in design of the power supply, and whether the power cord employed used RF-damping technology.
Follow Ups:
with Shunyata cords--a Python in particular. Significant improvement to all ears ni my system
Based on the linked review, this cord should combine the advantages of the NBS and the Power Wraps.
I've had good luck with a JPS Digital cord with my 861, the theory is it keeps the digital noise out of the rest of the system, apparently a standard cord acts like an antenna that radiates noise.
This is certainly possible. However, when I took a small portable AM radio, tuned between stations, and moved it around my 861, the only noise source I found was the display. Only when I attached an unshielded wire directly to the digital output did I get some noise from that part of it (I don't normally use a digital cable as I use the audio output of the 861). The power cord did not generate any noise I could pick up with my cheap radio test.This makes it seem to me that the Wadia is allowing other RF sources to contaminate the internal DC power busses through its AC power input. Power supplies may or may not provide effective isolation from contaminated lines; in this case it seems the Power Wraps make up for some deficiencies in the design of the Wadia power supply.
I dont think we can "blame" the 861 power supply. Afaik it is very well shielded and provides proper filtering (Shaffner filters?). If mains RF is a problem for the 861, it is also for a lot of other cdplayers.Now the AM radio test is interesting :) I dont even think I have one anymore, so I can't test myself, so one question:
What if you turn the display on the Wadia off? When I listen alone late at night, it seems that the sound is cleaner when I turn off the display... It's easy to fool one own mind on such matters, but if your radio-test gives similar results, we would at least ahve some sort of real evidence that RF influences sound is a negative way.
Sorry for the confusion. I left out part of the story for brevity.The AM radio gives lots of noise between stations. The only way to tell if one is picking up noise from the Wadia is to start and stop whatever function is under test.
In the case of the display, turning the display on and off makes particular radio noise (about mid-band) come and go. The signal is quite strong.
With an unshielded wire attached to the digital output, the noise is detected by starting and stopping playback of a CD. This signal is weaker than that from the display.
You are correct: the Wadia sounds cleaner with the display turned off, and I now routinely switch the display off unless I need it for setup or navigation on a disc. The sonic improvement from the Power Wraps is heard with the Wadia display off, so the display is not the source of the RFI that the Power Wraps are helping. There is no other digital equipment attached to the Wadia or nearby, so I don't know what else to blame except the Wadia power supply in my case. Since you can hear the effect of the display by its absence, you may also benefit from treatment such as the Power Wraps.
I also agree that mains RF is a significant problem for a lot of equipment, not just CD players. I also got an improvement by adding Power Wraps to the (stock) line cords to my Atma-Sphere MA-1 power amps. The biggest improvement came from adding them to the Wadia cord.
I had similar improvements by warping all major cables in a few layers of Aluminium foil. Give that a go.I will definitely try the suggestion of warping a wire over the PC.
Regards.
I'm not surprised to hear this. I use the Highwire Power Wraps to good effect on my transport, DIP and DAC. It's amazing how you can change the sound by sliding them a fraction of an inch from the center of the cable.I find the Power Wraps effective and imagine many people would. They are not as good as the Shun Mook jackets but in the right application, they are super for the money. Also good at this sort of thing are the Versa Labs Wood blocks.
Tha small wraps are nicely effective on video cables too.
Remove the Power Wrap from the NBS cord. Try breaking the cable in. Turn the Wadia on for 4 days with non-stop playback. The NBS cord is designed to be warm. If you need to tilt the top end a bit I suggest replacing the main ac outlet with something brass. The Cable Company sells the Michael Green approved Hubbell's for less then $15...this will provide the midrange and top end improvement your seeking. Please don't add Power Wraps to the NBS cord or you'll inject a lot of harmonics into the power supply that should not be there.Good Luck!!!
Regards
Alan
The NBS cord is five years old, and has seen Wadia duty for the last year. The sound has been consistent over that time. The outlet is hospital-grade on a dedicated 20-amp circuit wired with armored cable. This circuit sounds better for the Wadia than an adjacent dedicated circuit wired with Romex.The sound is improved, not just changed, with the Power Wraps. I hear details I never heard before, yada, yada.
Old trick used in preamps also..try wrapping the AC line with solid core 16-18 gauge wire for similar inexpensive benefits. Also try balanced power line and input glass beads and pulse transformer.
I tried this with solid core 10AWG wire on my captive power cords to no appreciable effect at all. Oddly, I DID get an improvement on my coaxial FM antenna feed! That suggests that it acts in an antenna or RFI capacity somehow.Was disappointed that I couldn't do a cheapy fix on the AC lines, however. At the time and with some suggestion from other inmates and some further reading, it appeared that standard copper solid core was no more an attractant for RFI than the copper stranded AC cords; reading suggested something like nickel could be 10 - 100 times as attractive to RFI. I did not have any source of that metal to test it out, however.
Knowing Leisure7's setup, I am encouraged to try the commercial Power Wraps in my system. Sometimes you just gotta pay to play...
Solid is just easier to wrap around whatever. Was/is used in preamp design when not using shielded input wire but one side is connected to ground!!! Commercial wrap sounds gimmicky to me perhaps using ferrite material like antennae core. But basically will have to work by shielding or RFI removal and we do have better ways to do so
than this w(C)rap. Try a 4.7 MFD VAC rated cap across transformers secondary terminal for easy cheap RFI removal...will work with everything!!.
nt
What is the effect from wrapping a metal spiral around the PC?Is it shielding or more like an RF stopper (ferrite ring)?
If it's shielding, it shoulnd't have any effect on a cable that is already properly shielded, should it?
Not sure whom you're asking what.In my system (NAD amp & CDP) the captive little power cords were not at all effected by my spiraling around them a 10AWG copper insulated wire in a configuration mimicking the Power Wraps. Nothing, nada, period. I did not assume that these cords were shielded, but didn't research that.
The reading I did suggested that certain metals, when wrapped around a cable, would attract RFI from the environment to them more readily that the cable they surrounded. The idea was that it would then "clean" the RFI from the desired cable, PC or otherwise. Proper shielding does this too, but many of our AA inmates use these wraps with properly shielded cables, so maybe typical shields aren't as good as we think. The coefficients of whatever it was varied greatly among metals. Copper, solid or otherwise, was still copper, while nickel was manifold as attractive to RFI (something like 10X, one was even 100X!). Started me believing that there could be something to this "Mu Metal" stuff.
Anyway, the FM coax feed IS shielded cable, and in this case it's quad shielded cable. Why the DIY copper power wraps improved reception there I can't say for sure. But in that case it must have acted like an antenna or antenna amplifier. I remember passive copper coils on old antennas were used to amplify reception years ago. That's my best guess there.
Only thing I can say for sure is that the simple DIY recipe suggested here was NOT effective in my system on PCs.
The Power Wraps are not simple copper wire. All I know is that they are attracted by a strong magnet, and copper wire is not. What I'm told is that the minimum order for the proper material is very large, so it is not practical for simple folks like us to make our own.The effect is to dampen a standing wave, that, because of the short length of the power cord, is at a "radio" frequency. A low-resistance conductor in the same shape simply rearranges the shape of the standing wave, and may shift its frequency slightly, but it does not dissipate the energy in the wave. Having a material that has higher permeability and some resistance helps by concentrating the magnetic field part of the standing wave, and dissipating the energy in the wave through Ohmic losses in the circulating currents induced in the Wrap.
The designer is an experienced aerospace engineer, and these are not snake-oil based devices. The only reason they require some fiddling to 'tune' them to the power cord is that they were made small to keep them cheap and make it easy to attach them to non-detachable power cords.
Please dont listen to marketing crap like that. I dont care if he's an aerospace engineer or whatever (apparantly they can't even shield flight electronics from cellphone interference :-)If the gizmo has an audible effect, it is doing one of two things:
1) Shielding the PC from RF that is radiated into it.
2) Filtering out RF noise that is already in there.I would guess that winding copper wire around the PC would work as a shield to some degree (probably not a very good one), but the power wrap gizmos you have there probably contain some iron alloy similar to the RF stopper you find on for example the cable between your computer and monitor. That one filters out noise in the MHz range (I have no idea about how many dB it attenuates at a given freeq. though).
So if it's doing 1), a shielded cable should be just as good, and if it's doing 2), clamping on an RF stopper should do the same.
Now if only I could find some place here in Denmark to buy cheap "clamp-on" RF stoppers I could do some testing myself...
Don Palmer is a retired aerospace engineer, and I'm a retired semiconductor engineer. I do believe we have a good idea of what is going on, and that you do not. Sorry if this sounds harsh; it is not meant to be so.The clamp-on RF stoppers would have little effect on a standing wave on a two-meter power cord, unless you used a lot of them. Then your cost would be greater than that of a Power Wrap. Your idea is interesting, though, and if I can find some in a salvage store, I might try making such a cable.
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