...I think that the sound of the TrueBlast horn is realistic and fine the way it is. I don't know why some criticize the sound. With one touch of the horn/whistle button on the transformer the horn gives the proper crossing pattern.
The crossing signal is a good, practical and often used prototypical idea, but I have an older Williams BL-2 Western Md dual powered A-A that has just a horn with no bell. The horn on these A units is very good sounding with programmed multiple "toots" and includes a slight echo type at the end of the play. I'm not sure if this is TrueBlast1 but the chip has ISD printed on the top. FWIW, I still believe the current TB2 bell sounds more like a blacksmith or farrier shop than a train bell. Nonetheless, Williams/WBB makes a good product for almost any budget.