# Balancing question....sorry!

That is pretty cool. I sincerely hope I don’t need it, but if I did, I’d only use it on beers that are carbed far outside the norm (fairly unlikely I’d want to have more than one tap of that style going at once).

I plan to serve my Duvel clone (just brewed today) at a party in November, and if I were to test drive the keg and couldn’t make it work, I might swallow my pride and spring for one of those…

In related news, I racked the starter off my Duvel yeast cake this afternoon and couldn’t help but take a sip. I was pretty surprised, but it was actually yummy ! I’m so psyched for this beer…

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Thinking a little more about the inline device, I guess it must have a finite range for which it can compensate. Probably not that likely, but it’d be disappointing if the resistance topped out lower than you needed.

For the folks with electrical background, this is a component that’s been missing from the dispensing circuit until now, which is analagous to a simple DC circuit. Pressure is voltage, flow rate is current, and we now have a potentiometer instead of searching for and trimming the perfect resistor !

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So then, do I apply more voltage on the pre-amp to git more gain, or do I saturate the signal with more potential from my pickup to drive the gain in the pre-amp? Gain, saturation are both the same but different, not sure then pre-charge the quantity with more gas, or use less gas and more time to let is absorb to make up the volume… hhhmmmm Sneezles61

Well, not to get technical, but gain and saturation are not the same as they’re classically defined, particularly when you make the distinction between linear and nonlinear behavior Gain is generally thought of as a linear commodity, meaning you put a signal in at one frequency and you get the same frequency content out. The ratio of signal levels is of course gain.

When saturation occurs, the linear gain actually drops, but some power shows up at harmonic frequencies.

If we were to make the electrical model closer to the gas/carbonation scenario, the ability of the liquid to hold carbonation would be represented as an RC element with a very long time constant (very high value R and C). Turn up the pressure really high for a short period of time and the amount of gas diffused in the liquid over a given time interval is limited by the resistor. Turn it up long-term, and the gas will become fully diffused to the same pressure (voltage ) as the gauge setting.

IF, however, you shake the keg to diffuse the gas quickly, I guess you’re kinda shorting or reducing the resistance to diffusion in the liquid, and your cap can be more quickly charged to the input supply voltage

I guess it looks like a capacitive divider, though, where the two caps are the liquid and headspace volume. That ratio and the pressure in the headspace determines what the pressure will be if you turn off the gas and it equalizes over time. I think

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Alright, I finally got my Duvel clone kegged this weekend, and aside from being a bit of a banana-bomb at this point, I think it’s going to come out well. The Duvel yeast was as finicky as people say…I did a 6 quart starter, fermented at 66 degrees, stalled, warmed it up, swriled, etc, and eventually had to add another active 2 quart starter. In the end, I did get it down to 1.008 or so, which should be good for a hair below 10% ABV.

I expect that the banana aroma/flavor mellows over time…hope so because it’s way too pronounced for me right now.

Now for the last step, getting it carbed and figuring out how to serve it just right. Hoping for the best!

I may have missed it…did you get your yeast from bottle dregs…or wy1388?

WLP570, the White version iof1388. I don’t think I have the patience to culture from a bottle, and certainly not for something you can buy off the shelf.

I’ve used 570 with very good results. I’ve not had undesirable off flavors, in fact I can compare it to at the actual Duvel. Sneezles61

Yeah, I’m really hoping the banana will fade. I think my cell count was good, it was well oxygenated, and temps were held around 66 before raising it up to get the last few points.

The banana flavor wasn’t really bad, i was just too strong for the beer to taste very Duvel-like. Hoping for the best!

I want banana and havent been able to get it!

I haven’t done a heffe wiesen in many years, but that was one that I recall bringing banana and clove to the party. Ferment warm though! Sneezles61