Whereas most plectrums are triangular in shape , the heike bachi is more square and angular .
The bachi , or plectrum , used to play the instrument , is also smaller and more slender than most plectrums used to play the shamisen .
Most plectrums are triangular in shape , the heike bachi is more square and angular .
The bachi , or plectrum , used to play the instrument , is also smaller and more slender than most plectrums used to play the shamisen .