Introducing Futura - The Modular DNA 20 APV by NexgenVapor[ISSUE]

[Amnesia1187]

Right, I was just wondering specifically about those panasonics. I have no idea what "NCR" means, but they are supposed to be ICR batts. So Li-cobalt instead of Li-magnesium. So, no good?

And that 2nd point is why I'm not totally sold. It is the same relative heat. Some of the juices I use with my hand built 2.0 ohm coils just always taste burnt above 3.5 volts (I run in VV not VW, so another reason I'm not sure about it). I find myself on 3.4 volts at 2.0 ohms with one particular juice, so not sure yet if the DNA20 is gonna get it. I'm in no way knocking your device or the chip, just not sure yet if it's right for me.

And I will have to agree that your device does look better. The modular format and apparent build quality are what is really making me consider the switch...

I just see the appeal of low volt/low resistance, especially on a device like the DNA20. Like Jon was saying, the important part is the heat (wattage) at the coil. I get why people might go lower resistance as a means of tuning a mech, but this is just compensating for a deficiency in a mechanical mod, it's not a performance factor. You do not have such a deficiency on a VV/VW device, so there really is no reason to make super low resistance coils. From what I recall, the DNA20 can push up to like a 4.2ohm coil all the way to 20 watts. Now building a good coil at that resistance would be a bit of a pain in the ... in my mind, as you would either need a MASSIVE coil, or use extremely thin wire.

My preference as a more or less sweet spot has been around 2.8-3.2ohms. On my latest build in my Kayfun Lite, I've got a 2.9ohm coil (5 wraps I believe of 30ga kanthal) that I fire around 5.3-5.6v. Now with a provari, it is slightly limiting, I believe I can go from 3w to 12w, which is more than enough for me as I don't think I ever go above around 10w, but even if you enjoy high wattage vaping, the DNA20 would have no such restriction and could push the same coil to 20w.

Side Note: Futura is now #2 in the review queue, and #1 is the Kayfun Lite, so in all likeliness, pbusardo will probably review both at the same time.

 

[LeftCoastVaper]

I just see the appeal of low volt/low resistance, especially on a device like the DNA20. Like Jon was saying, the important part is the heat (wattage) at the coil. I get why people might go lower resistance as a means of tuning a mech, but this is just compensating for a deficiency in a mechanical mod, it's not a performance factor. You do not have such a deficiency on a VV/VW device, so there really is no reason to make super low resistance coils. From what I recall, the DNA20 can push up to like a 4.2ohm coil all the way to 20 watts. Now building a good coil at that resistance would be a bit of a pain in the ... in my mind, as you would either need a MASSIVE coil, or use extremely thin wire.

My preference as a more or less sweet spot has been around 2.8-3.2ohms. On my latest build in my Kayfun Lite, I've got a 2.9ohm coil (5 wraps I believe of 30ga kanthal) that I fire around 5.3-5.6v. Now with a provari, it is slightly limiting, I believe I can go from 3w to 12w, which is more than enough for me as I don't think I ever go above around 10w, but even if you enjoy high wattage vaping, the DNA20 would have no such restriction and could push the same coil to 20w.

Side Note: Futura is now #2 in the review queue, and #1 is the Kayfun Lite, so in all likeliness, pbusardo will probably review both at the same time.

Very good points. The other reason to avoid low resistance coils in a regulated device is battery life. Here's a quick current draw comparison:

1.5 ohms @ 8 watts = 2.31 amps (current)
1.8 ohms @ 8 watts = 2.11 amps
2.5 ohms @ 8 watts = 1.79 amps
3.0 ohms @ 8 watts = 1.63 amps

1.5 ohms @ 20 watts = 3.65 amps
3.5 ohms @ 20 watts = 2.39 amps (8.37v!)

Battery life is a direct function of current draw. The higher the coil resistance, the longer your batt will last. In the example, a 3.5 ohm coil at 20 watts will drain the battery at about the same rate as a 1.5 ohmer at 8 watts. And yeah, the DNA 20 can run both at these levels, which to me is amazing.

The point is, low and ultra-low resistance coils should only be considered for unregulated devices. Of course, there are variables. Some lower resistance coils just work better than higher resistance ones, and vice versa. Depends on the mfgr., wire type, and a host of other factors, most of which I'm unaware. Generally, though, it's better practice to go higher than lower, unless you enjoy carrying a pocketful of batteries.

 

[Hoosier]

Battery life is a direct function of current draw. The higher the coil resistance, the longer your batt will last. In the example, a 3.5 ohm coil at 20 watts will drain the battery at about the same rate as a 1.5 ohmer at 8 watts.

UM, No. A battery is not a current supply, nor a voltage supply, it is a power supply with a fixed voltage. Power is a product of current AND voltage. The DNA-20 does not magically create voltage from nothing. It uses additional current from the battery to make the higher voltage. Except for circuit inefficiencies, the battery sees 8 Watts as 8 Watts. The DNA-20 sees it differently, but to a battery, power is power because it is a power source.


This is basic DC stuff and I'm consistently baffled as to how it is confusing. Should I be worried that I pre-ordered from a builder who misunderstands DC theory?

 

[LeftCoastVaper]

UM, No. A battery is not a current supply, nor a voltage supply, it is a power supply with a fixed voltage. Power is a product of current AND voltage. The DNA-20 does not magically create voltage from nothing. It uses additional current from the battery to make the higher voltage. Except for circuit inefficiencies, the battery sees 8 Watts as 8 Watts. The DNA-20 sees it differently, but to a battery, power is power because it is a power source.


This is basic DC stuff and I'm consistently baffled as to how it is confusing. Should I be worried that I pre-ordered from a builder who misunderstands DC theory?

You're right, of course. Batteries are power supplies. But I said that battery life is a function of current draw. That's why they're rated in milliamp hours (mah). And thanks for ordering!

 

[Hoosier]

I'm getting more worried now...

 

[nelsonm64]

i've always wondered if using a low ohm coil or a higher ohm coil vaping using wattage which would give you the best battery charge time, a 1.5 ohm or a 3 ohm. so now if i understand this right you'll get more battery charge time with the higher ohm coil?

 

[LeftCoastVaper]

I'm getting more worried now...

Ok, fair enough. Would you care to explain battery drain in an ecig? If I'm wrong I'd really love to know why.

 

[xpen]

I'm getting more worried now...

You shouldn't: this mod is powered by Evolv's DNA20... ;-)

 

[LeftCoastVaper]

i've always wondered if using a low ohm coil or a higher ohm coil vaping using wattage which would give you the best battery charge time, a 1.5 ohm or a 3 ohm. so now if i understand this right you'll get more battery charge time with the higher ohm coil?

Yeah, it's basic Ohm's Law. If you can fix the wattage then the higher ohm coil will draw less current, which equals greater battery life.

 

[xpen]

Have a look here http://www.e-cigarette-forum.com/forum/showthread.php?p=8364482 ;-)

i've always wondered if using a low ohm coil or a higher ohm coil vaping using wattage which would give you the best battery charge time, a 1.5 ohm or a 3 ohm. so now if i understand this right you'll get more battery charge time with the higher ohm coil?

 

[Amnesia1187]

UM, No. A battery is not a current supply, nor a voltage supply, it is a power supply with a fixed voltage. Power is a product of current AND voltage. The DNA-20 does not magically create voltage from nothing. It uses additional current from the battery to make the higher voltage. Except for circuit inefficiencies, the battery sees 8 Watts as 8 Watts. The DNA-20 sees it differently, but to a battery, power is power because it is a power source.


This is basic DC stuff and I'm consistently baffled as to how it is confusing. Should I be worried that I pre-ordered from a builder who misunderstands DC theory?

While I get your point, and do agree that you are correct (though I myself recently made the same argument as Jon before I was corrected) I fail to see what the relevance is with regard to ANY DNA20 device. 99% of building a DNA20 device is the mechanical side as the DNA20 is a complete package. Aside from soldering a few wires, there is no electrical work and certainly no real knowledge of the science behind the chip. That's kind of the point of using a chip like this rather than building your own solution, you don't need to be an EE to make a mod with one.

As to Jon's question, basically the reason the battery life doesn't change is because there are 2 different places where Ohms law is being applied (dunno if I'm actually wording this right).

DNA20 -> Atomizer:
Say you have a 3ohm coil and you want 12 watts, this would require 6 volts at 2 amps.

Where it get's confusing to many people (including myself until like a week ago) is that the DNA20 is not the source of the power, it is merely converting it. The batteries can only output at a single voltage (yes, this changes based on charge level, I am just referring to there not being any way to make a battery output higher or lower voltage while in use).

So, Battery --> DNA20:
For this example, let's just say at the moment the battery is outputting exactly 3.7 volts, and as mentioned before we want 12 watts of output, so we need to convert to 6 volts for our desired output. Long story short, while the DNA20 is outputting 6v and 2a for 12w, the battery must output at 3.7v and 3.24a for the same 12w.

 

[LeftCoastVaper]

While I get your point, and do agree that you are correct (though I myself recently made the same argument as Jon before I was corrected) I fail to see what the relevance is with regard to ANY DNA20 device. 99% of building a DNA20 device is the mechanical side as the DNA20 is a complete package. Aside from soldering a few wires, there is no electrical work and certainly no real knowledge of the science behind the chip. That's kind of the point of using a chip like this rather than building your own solution, you don't need to be an EE to make a mod with one.

As to Jon's question, basically the reason the battery life doesn't change is because there are 2 different places where Ohms law is being applied (dunno if I'm actually wording this right).

DNA20 -> Atomizer:
Say you have a 3ohm coil and you want 12 watts, this would require 6 volts at 2 amps.

Where it get's confusing to many people (including myself until like a week ago) is that the DNA20 is not the source of the power, it is merely converting it. The batteries can only output at a single voltage (yes, this changes based on charge level, I am just referring to there not being any way to make a battery output higher or lower voltage while in use).

So, Battery --> DNA20:
For this example, let's just say at the moment the battery is outputting exactly 3.7 volts, and as mentioned before we want 12 watts of output, so we need to convert to 6 volts for our desired output. Long story short, while the DNA20 is outputting 6v and 2a for 12w, the battery must output at 3.7v and 3.24a for the same 12w.

It's confusing, no doubt. But the battery life does change, depending on coil resistance, because the laws of physics deem it so. It's impossible to calculate exactly how much or how little since battery age and condition play central roles (internal resistance, etc.), but change it will - in one direction for the better, the other for the worse. This shouldn't entirely dictate your choice of coils but it's something to consider.

The one thing you've omitted in your description is that for a battery @ 3.7 volts and 3.24 amps to produce 12w, you'll need a coil at 1.14 ohms.

 

[Amnesia1187]

I'd also like to point out that the argument that Hoosier is making is akin to saying you don't trust the PCs made by Dell or Origin or Falcon Northwest, because they don't understand the science behind how the graphics cards they put in their computers works.

The DNA20, at least for me, has plenty of evidence indicating that it is the best power regulation chip currently being used in mods, I personally am going to choose to trust it.

 

[Hoosier]

Silly things keeps stripping out my paragraph separations and it hurts my eyes to see it, so I removed this post.

 

[Amnesia1187]

The one thing you've omitted in your description is that for a battery @ 3.7 volts and 3.24 amps to produce 12w, you'll need a coil at 1.14 ohms.

In a mech, yes, but not in a regulated mod. The output of a battery cannot be adjusted, so the voltage regulation chips essentially draw more current and convert it into voltage. The battery outputs 3.7 volts, the DNA20 draws 3.24 amps, the DNA then takes this and converts the higher current into higher voltage which results in 6v output at 2a. The power is consistent across the entire thing, you are always using 12watts.

The voltage and current actually being output by the DNA20 are essentially irrelevant to the battery, to properly measure the amount of current coming from the battery, you need only measure the power (watts) and the current voltage of the battery.

This is also the reason it is extremely important to only use High C rate batteries in most regulated mods, especially if you are planning to push higher wattages, and more so still if you are using 18350 sized batteries. If you are actually pushing 20 watts, then you are drawing around 5-5.5amps, which IMR batteries can do just fine, but batteries with lower C ratings could cause issues. This is much more pronounced in 18350 batteries, as even an IMR only rates at 8C which means that it's max continuous current is 5.6-6 amps, so it can handle it, but only just, and as the battery degrades, it just increases the risk. I personally wouldn't go above 16-17 watts on an 18350. Better safe than sorry.

 

[Amnesia1187]

The DNA-20 being the backbone is great, but I'm wondering if external switches are installed and if they were, how were they specified.

Jon actually mentioned in that interview on the podcast that the Futura uses the build in / on board switches for both the rocker and the fire button, which makes sense in a tube mod, as installing separate switches would just waste space.

 

[Hoosier]

Jon actually mentioned in that interview on the podcast that the Futura uses the build in / on board switches for both the rocker and the fire button, which makes sense in a tube mod, as installing separate switches would just waste space.

Fantastic!


Since I cannot get my last post to be anything but a block 'o text, I'll strip all that verbage out.

 

[LeftCoastVaper]

Jon actually mentioned in that interview on the podcast that the Futura uses the build in / on board switches for both the rocker and the fire button, which makes sense in a tube mod, as installing separate switches would just waste space.

All switches used are internal - no external ones at all. The adjusters and fire button are just actuators for the internal switches.

 

[Fred Rogers]

So what colors did everyone did everyone choose?

I picked graphite black.

-=fred=-

 

[HOPS]

4 more votes in the "review que" to put this in 1st place! How about a couple more votes, I'm gonna be ordering a mod soon to replace my wonky Vamo and wanna know which way the thumbs point lol...