No indeed, to be very clear, Lexel wants to build drivers to mod the Q8 with afterwards, and he sells them in another topic (click Lexel username -> my threads to find them)
The driver talked about now is that one, not going to be used in the Q8. Yes please use the modding topic for further discussion please.
Using the Q8 pretty often I am very happy with the driver as is
We had a party last Saturday and the Q8 with a simple cup as diffuser lighted the table for lots of hours (ramping a down from max so not to overheat it, still blinked twice so on FET) and I had not charged the 30Q cells beforehand
The little more efficient regulated medium modes do not seem like a big enough advantage to justify swapping driver for me.
If I wanted even more runtime I’d just put the 3500mAh GAs in for 10%+ more mAh compared to the 30Qs.
Or just carry 4 spare cells. A 4 cell carrier costs near (or under) a buck last I checked. Cheap enough and no hassles at all.
That is possible too it with the bigger li ion cells I don’t like carry extra.
The party was at the neighbors
In the barn they normally part the cars.
Very nice, when it got dark they put a construction light up, way too bright and wide angle in harsh tint.
So I placed the NW TN42 on med pointing at the ceiling and the Q8 with cup on central table
And light was good 
Am I the only one who thinks that using components with non-standart dimentions in developed to be customized Q8 is epic fail?
So many pages about this, I remember several hundreds pages ago we discussed if there is any need in retaining ring for driver. And after all this time, we see improvement which makes all existing 46mm drivers not suitable. :weary:
if you have read the Miller and others said the layout with screw holes on the driver is a final choice
also as the threads for the retaining ring are dropped the PCB got 1.65mm larger, filing this down on a 46mm final light is no problem
also I have looked at the original Q8 driver which is public to get the dimensions as well having 2 people measured the latest prototype sample
46mm drivers can fit in there the rim is 48mm, the component clearance 40mm as it is in SRK designs
There is no reason the 46mm driver wont fit without scres, you just need a paperclip or something similar to fill the gap around the driver
last but not least I am sending djozz a driver of my design to see if it fits
The SRK drivers I ordered from RMM long time ago had two parts needing filing to make them fit properly. These will work fine in the Q8 because of that I think (Q8 still at neighbors, drivers in part box so tricky to measure it now)
I hope you are one of the few seeing the current design as epic fail.
For one, when using 3V LEDs the stock driver is just a very good, solid nice working driver that needs no changing
Idk 16*7135 chips deliver 1400mA to each LED, how many lumens would that be?
I mean it is clear fet+1+n is better for lower to med regulated modes, hence we do it in the FW3A and probably in other specials from now on if no other tech blows it away.
Would getting 1312,5mA per LED from the FET be so much worse in terms of runtimes, what would be the difference?
At those relatively lower amps, is sagging a real big issue?
Really I don’t know.
If one goes for a mod with different LEDs then 3V there TA based drivers are not more expensive then others (are there a lot of other 46mm good drivers?) and are designed to fit perfectly.
I'm glad there will be time to order... I missed this one completely... Looks great though...
Another BLF A6 XPL polished version arrived a couple of days ago... I may order a couple more at current sale prices. I also have several friends that are ordering.. They were shocked at the power... LOL
No, current design is ok, it is smth like 4xA6 stacked together.
http://www.mtnelectronics.com/index.php?route=product/product&path=25_122&product_id=271
SRK host will carry around 20w (~7A) for long time usage. 1800mA/led for high cri nichia - very good lattern/extra photo light/emergency light. With good efficincy and easy calculating runtime. Much better, than any other light with external 4x18650 case.
The difference in output and runtime between the FET and a liner regulator is hard to calculate. It depends on a lot of factors. For example in the low modes (say 10% FET duty) the difference will be fairly large with the FET having less lumens and worse runtime. At higher currents the difference will be very little.
It gets even more complicated then this in reality since we are pwm the 7135’s as well but the end point is that having 3 channels will give you a bit better efficiency in the low and midrange modes but not much change above that.
The largest benefit with the 3rd channel is the regulation that it offers, the light will remain at the same output until the battery voltage drops out of regulation unlike the FET that will get dimmer as voltage drops.
Although all of this is still very old school in reality. A good buck driver would blow both setups away in every way.
these do work well for what we currently have available and are cheap. So they are perfectly acceptable to use.
I personally doubt that I will take the time or effort to swap to a TA driver in the Q8, I would rather wait for a nice soda can light with a 4s cell carrier that can handle some real power and a buck driver. Opens a world of possibilities.
This is a case when the Milwaukee M18 one key radius light is nice. Attach a 9.0 M18 battery and hang from ceiling or rafter upside down from the hook. Then control brightness and light direction from phone to fit the need. Totally overkill but beats lanterns, tailstanding flashlights, flood lights, etc in this use.
Best $150 on clearance I ever spent.
Nice!!! :+1:
Thanks for sharing slackwolf. I have never seen one of those. 
That would beat a flashlight in most cases I would use it for too.
I’m in for 2. Thanks!
Welcome to BLF!
Will update list later
Not in every way. The buck driver has the unfortunate limitation of having a set-point at the top, whereas the FET isn’t limited on the top end. Whatever set-point you choose, even if it is a high one, it will be too low for somebody.
True, For the first few minutes seconds indeed a FET driver can get you higher output. Although a good buck driver is not far behind and in many cases could even be superior in those first few seconds.
The only mainstream LED that comes to mind as being able to take more then a budget priced buck driver could put out is the XHP70, it can actually handle 15A+ (which could still be done with a buck driver but would cost a lot).
Everything else maxes out at ~10A or less. Which is not that hard to do with a buck driver. It will also regulate that output instead of dropping with the voltage unlike an FET driver.
For example the Q8 with a buck driver could run the LED’s in 4s with 4S cell input. It would only need to output ~6A to max out the LED’s in such a setup. Pretty easy for a reasonable buck driver to handle. Any more then that and you risk killing the XP-L’s.
ill take one of these as well thanks.
Welcome to BLF!
Will update list later.
Yeah TA but we differ for I really like parallel cells, you love series.
I would not like my Q8 to NEED four married cells to function, I like 2-3-4 cells use to be a choice and a main attractive thing of SRKs but that is very personal I know
What’s wrong with using the modding thread for mod talk?
It’s probably because of the “Add new comment” text
It’s below the latest response posted on the thread.
It can be read as a direction to do that.
Oops.
If only it could be changed to say “Add new comment here if you have something to contribute on this topic”