I have been discussing this new product for some time now during its development stages in the What’s On the Bench Thread. But I think it is time for its own dedicated thread. This usually happens when we reach a point of critical discovery or progress. Today is that point. We have conclusive data showing that a parallel plug-in filter (not a flow through filter) can reduce SMPS noise that contaminates AC mains power lines and outlets strips. The SnubWay Noise Defender is a compact module with a 120vac NEMA plug for the U.S. and Euro compatible Schuko plug for the 230VAC EU market. The 230VAC version remains to be tested.
I initially showed that the SnubWay can filter out 60kHz to 400kHz signal from a function generator imposed on an outlet strip. This was not plugged into a wall outlet or any real equipment.
Recently, I have made tests using a spectrum analyzer to look at the noise floor of the audio output of real devices to see if the noise floor can be improved by plugging in the SnubWay. I had a small SE Class A headphone amp (LuFo Lite) repaired and so I thought why not look at its noise floor. I was pleased to see that there was some 3kHz to 5kHz “grass” on the noise floor that was subsequently cut down by the SnubWay.
Above is a photo of the test in progress. You will notice the funny lampshade on the LuFo Lite (needed to cover the bright halogen bulb acting as resistive loads in the signal path). Here is the closeup of the noise floor cleanup:
Here is a photo of the MC phono line stage (Jhofland’s interpretation of a Pearl 3). It has a separate linear PSU connected by an umbilical to keep the noise low.
Here is a photo of the bench setup used to measure the phono line stage:
The noise floor of a phono line stage is one of the most critical low noise audio devices that we use in our systems. Given that the gain in these systems is around 60dB (that’s 1000 x) any sort of noise can be amplified and heard. Which is why it’s important to have as clean of a power source and power supply as possible for MC phono stages. Here is the measurement of the impact of the SnubWay for the output of the phono line stage:
Here are technical details of the testing:
Spectra were acquired using 256k length data sets acquired at 192kHz and FFTs processed with Blackman Harris 7 window function with 16 averages. Focusrite 2i4 USB audio interface and REW software. 100kHz 8th order passive brick wall filter on FFT input to prevent data aliasing from high frequency content. FFT scale: 0dB FS is 2.2vrms.
And here is what it looks like to use the SnubWay - simply plug it into the power strip:
Here is what it looks like inside:
It is a parallel network of 5 LRC filters designed using LTSpice circuit analysis and laid out on a stack of 3 two sided PCBs using premium SMT devices such as carbon film high energy pulse resistors, X2 rated safety film caps and CoilCraft shielded inductors. There is also an MOV/GDI for lightning suppression and protection from high voltage transients.
The 3D printed prototype looks like this:
The final product will be in satin anodized CNC’d aluminum with a premium Viborg acrylic base and copper wall outlet pins/blades.
We are now working on CAD models to produce the SnubWay that will look something like this:
We are still debating on final finish and color choice.
Here was an early test of the prototype as a P2P circuit and tested with a function generator noise source.
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I will ask my brother in law to explain how this works as he has a phd in electrical engineering. The problem for this proud artsie is that his answer might take a doctorate to understand. My brother is a mechanical and my niece married a chemical so I have backup options. Thanks for everything you do.
This is the 8 rotor equivalent, fused into one long rotor!
I am a big fan of Mazda 787B LMP car.
It was so good, they banned it. Sort of like how the 917 dominated the season it was introduced and subsequently banned.
I am a big fan of Mazda 787B LMP car.
It was so good, they banned it. Sort of like how the 917 dominated the season it was introduced and subsequently banned.
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Great design, love the rotor profile, loved that car as well, never a P fan so the 917 was impressive, just did not like the brand.
Reminds me of a short track oval race car built in my home town in the 70's. Aluminum monocoque chassis, 4 triple cylinder 750 Kawasaki engines made into a pancake engine, twelve expansion pipes, stupid fast, ear bleed loud and not a pleasant sound in the least. One race, stomped all the regular and very high tech V8 powered cars, permanently banned. Guy never paid for the one off chassis build, I knew the amazing builder.
Anyway, another great product on the way!
Reminds me of a short track oval race car built in my home town in the 70's. Aluminum monocoque chassis, 4 triple cylinder 750 Kawasaki engines made into a pancake engine, twelve expansion pipes, stupid fast, ear bleed loud and not a pleasant sound in the least. One race, stomped all the regular and very high tech V8 powered cars, permanently banned. Guy never paid for the one off chassis build, I knew the amazing builder.
Anyway, another great product on the way!
A car and or car audio thread, which we talked a bit about before, would be great. I am ready to start posting on one
I wish I knew more about that crazy race car, it was super low weight which was nearly all barely above ground level, big fat tires, huge wings, offset ending and diff as had solid rear axle due to the specs in the series. I was called CAMRA or something like that, just in the Northwest US and Western Canada and quite costly to run a team in. One of the drivers won the Indy 500, Tom Sneva, lived two blocks from me.
I wish I knew more about that crazy race car, it was super low weight which was nearly all barely above ground level, big fat tires, huge wings, offset ending and diff as had solid rear axle due to the specs in the series. I was called CAMRA or something like that, just in the Northwest US and Western Canada and quite costly to run a team in. One of the drivers won the Indy 500, Tom Sneva, lived two blocks from me.