Here is my sending CQ received by Soft66LC4 and HDSDR.
This is the beginning part of the message. The AGC is set to slow, and the bandwidth is around plus_minus 200Hz.
And this is the ending part. The audio file is here.
IC-7410 vs. Soft66LC4
If you wish to compare the sound from two receivers listening to the same RF signal, you need a spliter.
A 3dB hybrid transormer is the desired solution, but you can use a resistive tee with obvious disadvantages such as a greater loss and poor isolation between the ports.
http://en.wikipedia.org/wiki/Power_dividers_and_directional_couplers
The RF signal, fed into a dummy load, from IC-7410 at 7026.00kHz is received with Soft66LC4 at 7025.828kHz with almost no audible beat from the two nominal 600Hz tones.
So the difference bewteen the two LOs are around 172Hz.
Listening to the same CW signals with IC-7410 and Soft66LC4 simultaneously, it seems to me that the sound from Soft66LC4 and HDSDR is preferable.