Strange results with all pass compensation
UPDATE: As Hilmar pointed out, OP did convolution in the time domain (as is clear in this code). This answer is misleading so will be deleted).
You would not convolve the two responses as you are in the frequency domain. It is the time domain impulse response of the equalization filter that you would convolve with, and convolution in the time domain is the product in the frequency domain. For the product of complex signals, the phases would add, so in your simple example (which may not be realizable due to causality) the phases would add to zero.
For the product of complex signals, the phases would add:
$$K_1e^{j\phi_1}K_2e^{j\phi_2} = K_1K_2e^{j(\phi_1 + \phi_2)}$$