Serpent Music is now producing all instruments both in D-windway, and the new curved-windway designs. The D-windway whistles are quieter and just a bit more chiffy, while the curved-windway whistles are louder (the copper and brass 5/8" bore D’s are definitely session whistles!) and are “sweeter” in tone, though I’ve designed enough chiff in that they’re not going to sound like re***ders. 
When you order any whistle from Serpent Music (except the Village Smithy, which is a flat-windway instrument), be sure to send email specifying D-windway (soft tone) or curved-windway (loud tone). I’ll get the options up on the site as soon as I can - it’s being worked on right now by my wonderful Web Designer!
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