As both COBs and quantum board samsung 301b use LEDs but they both vary in the white color spectrum scale. Some other differences are as follows:
Area coverage
The main thing that distinguishes between a COB and a quantum board is the area covered by these lights. A COB light has a single source of light, hence the light does not reach the outside area completely as compared to the middle section. On the other hand, a quantum board comprises diodes that cover the complete area uniformly. It does not cover the center part only. Quantum boards have more light spread, while the COBs only provide the central light spread.
Penetration Power
This difference comes out from the first one. As COB has strong light emission, it penetrates deeply below the canopy, especially in the middle part. The light penetrates slowly as it moves towards the outer part. Quantum board lights also have great penetration power but this is not as good as the COBs.
Heat Management
The main difference that comes for COB Vs quantum boards canada is heat management. In the case of COBs, the small diodes, mounted on a small board, emit a great amount of heat. Single COBs are cooled down by heat sinks, however, multiple COBs use fans. On the contrary, a single aluminum board is used to cool down the quantum boards. These lights emit the same amount of heat as COBs, but the individual diodes are kept safe from overheating through passive cooling and a heat sink. This video adds more to your insight during this comparison.

Similarities between COBs and Quantum Boards
COBs and best quantum boards are pretty much similar to each other and are best for indoor plants.
Same principal
A COB light comprises of numerous tiny LEDs, inserted on a single chip. However, a quantum board also uses the same LEDs but with more space between the LEDs. You can say that a quantum board is a large COB.
DIY Setups
Both of these grow lights are best if you want to build your lighting system. You can take the DIY kits from the manufacturer and all you have to do is to put all the components together. Both COB and eco farm quantum board have a similar DIY Setup so you can easily create it by yourself.
Similar Spectrum
Both of these lights use bright full-spectrum white LEDs. Hence, they produce different colored lights depending upon the temperature. The frequently available color temperatures are 3000K, 3500K, 5000K, and 6000K. The red wavelength produces the warmer white light, while the blue wavelength produces the cooler light. The warmer light is suitable for plants and the cooler light is for vegging。