Post some adress of this product here if you can have one or two...
Thanks.
There are at least a dozen models available.
How noisy is my line? Audio Prism Noise Sniffer
A friend and audio journalist had this Prism device, and he plugged it into various outlets when I visited him. It gave a clear sense of which outlets were noisy and how effectively his conditioners were helping with noise.
He said these were not made any longer. Does anyone know of another tool like this?
It seems like it could save someone with clean power (or a quiet outlet) a lot of money from conditioners/regenerators which would not necessarily help.
- ...
- 25 posts total
These observations are interesting: https://www.audioshark.org/power-conditioners-regulators-24/measuring-ac-power-line-noise-11713.html
Just an extract of this very informative thread... :
«The Emtech is no longer being made. However, you can find some used ones on the eBay. The Enteq is useful for rudimentary demonstrations. However, it is not a good device for a comprehensive study of power line noise. First, it is has no standard references settings. You plug it in - you adjust the gain with the knob until you get a approximate 100 reading on the meter. This is arbitrary - not a measurement where you could compare two different power lines and certainly not compare readings between locations. It is however useful for a quick before and after of the same power line. You must be careful NOT to touch the gain control between readings and the readings should be taken very close together since power line noise is dependent upon the radiated RFI/EMI noise in the environment. «I have several of the Alpha and the Stetzerizer units. Personally, I prefer the old Entech unit. Entech was actually a very technically advanced group of engineers. Both the Alpha and Stetzerizer are similar in that they have a bandwidth that extends quite low for measuring RFI/EMI. They drop down to 15-30 kHz in there measurements. While this may seem to be an advantage it actually has a fatal flaw. Both aggregate noise from about 15 kHz to around 10 MHz and lump them all together in a single reading. Some frequency bands are more important to the performance of audio equipment specifically our research indicates the the most harmful frequencies are in the 100 kHz to around 1 MHz bands and then secondarily from 1 MHz to 10 MHz. Interestingly, I believe that the Entech engineers knew this and designed their device to be sensitive in the frequencies from 300 kHz to 700 kHz range. This makes the Entech particularly useful for finding noise sources in the specific ranges that are most noticeable in the context of music systems. I have done direct side-by-side comparisons using all of the units listed. I would then plug a device into the power line that we ’know’ produces particularly harmful noise effects as measured by our power and spectrum analyzers. In many cases, the Alpha and Stetzerizer would barely change their relative readings while the Entech would go off the charts. This is because the Entech is more narrowly focused and the other two are less so. And then conversely I would connect filters that reduce power line noise in a known manner as verified by the power and spectrum analyzers and in many of these cases the Alpha and Stetzerizer would show only as small or marginal difference while the Entech would show a much larger and significant difference. Look these are all very inexpensive devices and all of them can be useful. But they have severe limitations from a technical point of view. I found the most useful for the hobbyist to be the Entech. As I said earlier, we are developing a device that will be much more useful and will show noise in specific bands much like the old audio spectrum displays. This is being developed for our medical division where this device will be quite useful in identifying specific types of noise pollution in hospitals. I hope this is helpful. BTW, I have three of the Alpha units and would be happy to sell two of them at less than what we paid for them. Just PM me. Caelin Gabriel President Shunyata Research |
There is a huge, literal gap between professional power quality meters such as by Fluke and audiophile toys. The gap is in the frequency band they cover. The pro’s measure noise and distortion in the range of motor frequencies and the audio band, and the range we care about for power supplies. The toys they sell audiophiles are usually poorly specified or measuring noise so high in frequency we may never even hear it. Chasing down a 1 MHz RF signal is a rabbit hole that can send you down spending money you don’t even need to spend. This is one major reason I like surge and noise filters from Furman wiht SMP and LiFT, as well as the series mode protectors by SurgeX, etc. The series protection starts filtering down at 3 kHz, while many RFI/EMI filters don’t even work below 100 kHz. My other bit of advice is to separate out noisy wall warts and keep them away from the clean side of your power conditioners. If you _must_ invest in these power noise ... gizmos, at least find out the range of frequency at which they are working at, so you know what the signals mean. |
- 25 posts total