Someone tried latest Samsung H-Series Strips, gen.3?
They use similar 561c like the quantumboards and use a 8SxP series-parallel layout for 22,5vdc, only a bit pricey.
http://www.digikey.com/products/en?keywords=SI-B8V11156HUS
Here is a quick direct comparison with different currents (250-1400ma):
QuantumBoards (304 SMD561C [38S8P], Flux bin: S5, Voltage bin: AY/AZ)
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Voltage(Min) Voltage(Max) Current(mA) Watts per Board(Min) Watts per Board (Max) Max Lm/W(40C) Min Lm/W/Eff.
100.7 104.5 250(31.25mA) 25.17 26.12 195.7 188.8,
101.8 105.6 350(43.75mA*) 35.64 36.97 191.4 184.6, Ø60.0%
102,7 106.5 467(58.38mA*) 47.89 48.82 187.7 180.4, Ø58.0%
103.3 107.1 500(62.5mA) 51.68 53.58 184.8 178.3
105.2 109.0 700(87.50mA*) 73.68 76.34 178.1 171.8, Ø55.0%
108.3 112.5 1050(131.25mA) 113.71 118.1 167.5 161.5, Ø52.1%
111.0 115.1 1400(175mA*) 155.34 161.19 158.8 153.2, Ø49.4%
Samsung H-Series Strips (48 SMD561C [8S6P], Flux bin: S5/S6, Voltage bin: AY/AZ
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Voltage(Min) Voltage(Max) Current(mA) Watts per Strip(Min) Watts per Strip (Max) Max Lm/W(40C) Min Lm/W/Eff.
20.6v 21.5 262,5(43.75mA*) 5.37 5.97 191.5 193.5, Ø60.0%
21.0 22.0 350(58.33mA*) 7.35 7.70 187.4 184.0, Ø58.0%
22.0 23.0 480(80mA) 10.56 11.04 177.0 180.0, Ø56.0%
22.5 23.5 525(87.5mA*) 11.85 12.35 179.1 175.4, Ø55.0%
23.0 24.0 700(116.67mA) 16.10 16.80 171.9 168.5, Ø53.5%
24.0 25.0 1050(175mA*) 25.20 26.25 158.8 153.2, Ø49.4%
*matched currents
Holy shit, my line breaks were not taken into account. F ...!
But I think it goes so synonymous and you guys can see what is meant.