I modded D4 with quad Optisolis
Now D4 is $45 (maybe without leds it’d be cheaper), I don’t remember if you have to pay extra for KR4 driver. Optisolis quad board is around $5. So that’s $10 more than S2 triple.
What do you think?
Re: buck91
S2+ hosts ordered. Aiming to use default driver on most of them.
This nice writeup shows 4.5 kHz pwm, should be fine. Low mode is 30-40 lumens, which is much higher than requested. Runtime is fine but unregulated. Convoy S2+ measurements (7135*8 3B) | Candle Power Flashlight Forum
The kaidomain board has the same modes, just constant current. Moonlight special driver is out of stock. I checked the forum sticky for known good drivers, but most links were broken. Best I can offer is the 20+$5 shipping guppy driver which does have moonlight. That brings price from 50->75 dollars, which is too much for an s2+. Edit: found a qlite driver with guppy for 5usd
So I have another idea. My next round was going to use Jetbeam rrt01 2020 version as hosts. I can source a few now. 2.65-3amp depending on battery. No pwm. Good, but unregulated runtime. The lowest modes I’ve seen (use one on my nightstand). Sometimes it displays a barely perceptibe ripple/flicker on extreme lows, but turning on and off gets rid of it. If you don’t mind waiting on me to get the build details figured out, I can do one for 65(host)+10(optic/led/pcb)+10(shipping)+10(profit)=95 usd
Re: Scotty 321
5700k is doable with 5000k and 6500k tint mix. I’m not doing d4 or dt8 mods now, if you don’t mind asymmetry, I could do two 5000k and one 6500k, but the front will look funny.
Re: g-damian
Cool build! Appreciate the firmware notes. I got host and spacer for 17 usd, and shipping, labor, and optic/pcb/led together are 30 usd. So 50 for the Convoy, 80 for the d4. Not a bad idea. I’d personally rather do the dt8, more lumens in a similar package.
I currently have 15 triple mpcbs on the way, so I’d need to use those first.
Re: PyriteParachute
5000K would be fine. 
Update: finally got the LEDs ordered. Various temps, more than needed, so that I don’t run out in case everyone wants the same.
Have interest for 12 lights, can make 15. In the even that there are too many interested, I’ll handle the requests in the order I received them.
410 usd spent on materials so far, base price for a default 3/5mode driver s2+ is 50 usd, shipped to CONUS. Happy to ship international, so long as buyer covers part of the difference.
If you request another driver, I’ll ask you to pay extra. The driver-swapped builds will be delayed, as I’ll do them last.
Hoping to have these built and sent out by the end of October.
Here are the best drivers I could find:
6 usd: http://kaidomain.com/BD39-17mm-2200mA-3V-9V-1-cell-or-2-cells-Buck-Driver-Board?search=Buck
Same low-medium-high as the default driver, but no pwm, more efficient.
5 usd plus shipping: QLITE REV.A 7135*8 3.04A LED DRIVER - 17mm
Guppydrv allows for moonlight, but I assume there will be pwm.
11 usd plus shipping: led4power
Linear, not buck driver. No pwm AND moonlight.
20usd plus shipping: 17mm MTN-MAXlp HP 1A-5.5A Low-Profile Buck Driver - 5V-18V
Guppydrv, moonlight and no pwm, may be more efficient than theled4power one.
What triple mcpcb are you using with optisolii?
This one: https://asflashlights.com/home/134-sinkpad-copper-mcpcb-for-cree-xm-l2-xh-p-50.html
Url is misleading.
PWM is desirable on a very high CRI light as dimming with a constant current driver places the current range in a less than favorable location and often incurs poor tint and cri shift.
Noob question here (from me)… So are you saying that to get better CRI at lower lumen modes that PWM is preferred? I’m not planning on taking pics or video with this light, so would I be better off looking at the PWM options?
Some LED models like the Luminus sst-20 get green on the lowest outputs. So emulating that brightness with pulses of a higher brightness should be less green. That being said, I don’t know of data that supports lower cri at those low settings. The only time I’ve seen worse cri readings is when the emitter was being overdriven.
Most Nichia LEDs have little, it any tint shift at different outputs.
Thank you for the info. When would you need me/us to make a decision on the driver? If I’m not sure, could I just list a few preferences and have you decide what is the closest (I’m a noob on this stuff)?
I’ve made a few Optisolis triples and 1 quad s2+ now. If I recall there is virtually no tint shift even at extremely low output, and it certainly looks that way. Rainbow Moonlight.Then again, my reference is being driven by a Qlite board reduced to running two 7135 chips.
Great project, spread that quality light!
Plenty of time, won’t start on these till October. Yes, I’ll help pick a driver. I got the hosts in, only disadvantage of the included one is that the low mode is quite high.
Thank you!
Things I would prefer (in order of importance… at least for my plans for this light):
1. LVP
2. ML from off (not from memory)
3. Turbo or Hi from off (not from memory; it’s OK if it needs to be in a different mode set, i.e. SL’s 10 tap or guppydrv)
4. Modes in between ML and Turbo/Hi (ramping is fine)
5. Not a fan of PWM
I would have originally asked for the guppydrv option (the most expensive of the ones on your list), except I’m worried about no LVP for my uses. If you think that a quality battery with LVP is good enough (and will fit), I’m OK with this option. Side note on battery fit - ideally I would like to use one of my 18650 w/USB charging port, but am OK with normal protected 18650’s if necessary for this project.
5700k / 6500k
interested please
Interested in a 3000 and a 4000
A drjones driver may work for this, but I’d need to disable the fet somehow. LVP not explicitly specified.
Only 5000k and 6500k leds available, would need a quad host to hit that temp. I’d be willing to do that after using up my 15 triple mpcbs.
Lordlupulin, assuming all others remain interested, your pieces are number 14 and 15. Any further builds will require new parts and might be delayed till the end of the year.