This paper describes two new algorithms for blind source separation (BSS) based on frequency-domain independent component analysis (FDICA). One is FDICA with pre-filtering by a speech sub-band passing filter to slow down the learning speed in low signal-to-noise ratio (SNR) sub-bands. The other is FDICA with sub-band selection learning to reduce the number of iterations for those sub-bands. The results of speech recognition experiments show that each method can improve word accuracy by as much as 7% and that the second method can increase the speed by approximately 60%.