Its a fairly common question:
And the answer is.. YES. Though you are going to have to use some third party tools. The quick solution is find a ‘SoundFont’ online you like for Windows. These are files you can download from many sources on the internet, free and not so free, that tell your computer what each PriceSquawk sound will actually sound like e.g. Electric Piano 1 = X, Trumpet = Y
You then use some third party software for using the new SoundFont instead of the Windows default.
Here are some resources for downloading your SoundFont:
Digital Sound Factory (paid or download their sample)
Synthzone SoundFont Resources (links to free SoundFont resources)
SynthFont Resources (links to free SoundFont resources)
Here is the (free) software you need for using custom SoundFonts:
And here are some detailed instructions on making it all happen:
AracnoSoft Instructions and SoundFont
If after browsing all the SoundFont resources you still want to use your own wav files – then you can create your own SoundFont from scratch too.
Here are some resources on achieving this. Viena (with one ‘n’) is the most popular free SoundFont editor:
How to edit your own SoundFont on Musescore
Viena Free SoundFont Editing Software
A lot of the commercial SoundFont sites provide demo SoundFonts. I have found the digitalsoundfactory.com example SoundFont great. It is what I am using in the video below. The default sounds should suffice for 99% of traders – as you have a choice of 127 instruments to choose from for trade sounds, and 180 total for Alerts. But if you are a true audiophile, you can make the market sound like whatever you want using customized SoundFonts or making your own.