Bybee Music Rails Problem

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Here's a graph of Zout and Tg -- you can see the broad impedance dip centered around 120Hz, and two little kinks at 60 and 180 Hz -- at both of these points the phase margin is in the low single digits. At the zout minimum the phase margin is in the low 20's. Yes, it certainly is a filter, or combination of filters:

An externally hosted image should be here but it was not working when we last tested it.


Edit: And here's the comparison of noise -- it's not "V", but V per root Hz on the left axis:

http://www.linearaudio.net/images/letters.pdf/V4 JW F7.pdf

Programming the AP is such fun.
 
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Erlend, I am glad that you finally achieved success in getting it going. It DOES work, perhaps not in the same way as a DC regulator, but it DOES work. I use them to lower the noise in my Lab power supplies.
I think it helps for 3 D and clarity. But I also think It would be better with some other caps than Siemens mkt. and carbon resistors. The sound is getting a bit " hard" in midrange.
 
Erlend, I just spoke, at length to that engineer who designed the Bybee Music Rail. I told him of your (mistake) you know 3.9 rather than 3.9K, and we both laughed a little. He is now designing the same Rails into one of my Vendetta Research phono preamps with some success.
 
Erlend, I just spoke, at length to that engineer who designed the Bybee Music Rail. I told him of your (mistake) you know 3.9 rather than 3.9K, and we both laughed a little. He is now designing the same Rails into one of my Vendetta Research phono preamps with some success.
So after reading this overly long thread am i correct that the bybee Music Rail address the major problem in USA (60 hz) power supplies the second order 120 hz problem that is so large. At least to me sounds like a solution for a problem that is there just about all of the time. Have I missed some thing of import here ?
 
Why are people comparing the Music Rail to a regulator, and complaining that better regulators are better regulators? The Music Rail is not a regulator, it's a capacitance multiplier, just a good small ripple filter. It looks to me like a convenient robust time-proven capacitance mutipler with all the bells and whistles for good performance without having to engineer one. In fact, to operate it requuires you already have decent regulation.

Like in my 500 volt tube amp power supply I have a big 1000ufd screw-terminal can electrolytic that's EXPENSIVE (and a 100ufd bypass cap), then an enormous choke that's EXPENSIVE, and then I'm considering the comparatively cheaper bybee with its necessary related components for 500V service (instead of another expensive 1000ufd cap), and finally I would have a 100ufd cap (or more) to remove any swtiching artifacts from the ByBee Music Rail. The Bybee Music Rail takes the place of another 1000ufd cap for less money and is a LOT smaller, and the start-up in-rush is of much shorter duration, like with any capacitance multiplier. The penalty is a bit of voltage drop.

There are two models of ByBee Music Rails: one has a wider voltage window and more current handling but more voltage drop. If your regulation is poor you may need the heavy-duty one even though your current demand is not a lot, just because it has a wider operating range; the penalty is that you have to tolerate the greater voltage drop of the heavy-duty bybee.

I wish I really had more info about the ByBee Music Rails. They don't really provide much in the way of specifications.

I'm particualry interested in how to model it at start-up. My inductor is large and in modelling it can sometimes cause the voltage to overshoot and oscillate a bit at start-up. With a large can in the final filter, that load keeps the voltage more stable.

I wish I could get more useful posts contributig real info.

I have no idea what their magic quantum flux capacitor time-travel speaker bullets are, and I sure wouldn't buy one without finding out first.
 
Why are people comparing the Music Rail to a regulator, and complaining that better regulators are better regulators? The Music Rail is not a regulator, it's a capacitance multiplier, just a good small ripple filter. It looks to me like a convenient robust time-proven capacitance mutipler with all the bells and whistles for good performance without having to engineer one. In fact, to operate it requuires you already have decent regulation.

Like in my 500 volt tube amp power supply I have a big 1000ufd screw-terminal can electrolytic that's EXPENSIVE (and a 100ufd bypass cap), then an enormous choke that's EXPENSIVE, and then I'm considering the comparatively cheaper bybee with its necessary related components for 500V service (instead of another expensive 1000ufd cap), and finally I would have a 100ufd cap (or more) to remove any swtiching artifacts from the ByBee Music Rail. The Bybee Music Rail takes the place of another 1000ufd cap for less money and is a LOT smaller, and the start-up in-rush is of much shorter duration, like with any capacitance multiplier. The penalty is a bit of voltage drop.

There are two models of ByBee Music Rails: one has a wider voltage window and more current handling but more voltage drop. If your regulation is poor you may need the heavy-duty one even though your current demand is not a lot, just because it has a wider operating range; the penalty is that you have to tolerate the greater voltage drop of the heavy-duty bybee.

I wish I really had more info about the ByBee Music Rails. They don't really provide much in the way of specifications.

I'm particualry interested in how to model it at start-up. My inductor is large and in modelling it can sometimes cause the voltage to overshoot and oscillate a bit at start-up. With a large can in the final filter, that load keeps the voltage more stable.

I wish I could get more useful posts contributig real info.

I have no idea what their magic quantum flux capacitor time-travel speaker bullets are, and I sure wouldn't buy one without finding out first.

Show me the switching artifacts, and I'll show you how to eliminate them, but switching artifacts are usually in the tens of kHz to under 10 MHz. They are a bigger problem with switch mode power supplies than what you describe.

I will be happy to give another listen to the BRM with the panel. It faired so poorly compared to the other devices inserted between the raw power supply and line stage that I was puzzled. It did "filter" as claimed.

None of the panelists were aware which device was being used to drive the line stage, so there was no ex-ante "elisir d'amor" bias. This being said, the line stage, (Borbely All-JFET preamp) current draw was pretty stable, but the amp itself had relatively poor PSRR which we felt would be appropriate for the test. Perhaps the BRM is more suited to an AB or B power amplifier with high current charging cycle.

In the article I explicitly stated that it was not a regulator.
 
To clairfy, the device might not even be a capacitance-mulitplier, it might generate a correction signal, etc. I was just frustrated with the thread havign so much irrelevant data about the wrong product, the voodoo markting, the wrong appilcation, or wrong expectations.

What article? Did I miss some actual valuable data somewhere in this muck? Anybody acutally know what it really is and how it works? I'm not really looking for magic, I'm looking for a capacitance multiplier that won't have such long inrush at start-up but will get rid of the bit of ripple left after my choke. It does seem strange to use a big cap as a final filter, when it's only the last bit of its capacity that actually is depleted and replenished.
 
cyclecamper said:
It does seem strange to use a big cap as a final filter, when it's only the last bit of its capacity that actually is depleted and replenished.
I thought the whole of a capacitor contributes to capacitance, except at very high frequencies? If you mean 'charge' instead of 'capacity' then your concern would apply to any capacitor which has a DC bias.
 
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