I would like to know how this whistle sounds, but couldn’t find any tune or review… anybody knows where can I get some mp3 or something?
Thanks!
Cristian: The Viper has a very full sound, with a very powerful bell-tone. As with most AlPros, it has only a hint of chiff. The instrument plays over its entire 2+ octave range in an amazingly linear fashion. There is no ‘jump’ in volume at the shift, or further up the second octave. Unlike a number of low D’s I have played, it is truly playable over both octaves, and retains its ease of playing even on the highest notes in its range. It does not require excessive amounts of air. Its lack of playability ‘quirks’ is one of the Viper’s outstanding characteristics. Because it is smooth aluminum, I had a bit of trouble at first (many years ago), in feeling confident concerning holding on to the instrument. I was always afraid it would somehow slip from my hands. I find that my fears were completely unfounded. It is really no more slippery than any other low D. As always with a Burke, intonation is spot-on. I play two low D’s, regularly. While I am certainly not going to sell the other one, my Viper is a respected part of my arsenal…
Be well.
Byll
Great review, thanks a lot Byll! 
My wife has ordered one for me, but didn’t want to let me touch it until Christmas, until I reminder her that, as will all musical instruments that are shipped, I really should have it for at least 10 minutes to make sure it arrived well.
However, last Wednesday I was shocked to see that someone else in my are (Delaware) actually had a Burke whistle… I thought I was the only one. ;p I asked him to let me give it a go and yes… it sounds absolutely gorgeous – it has the trademark Burke ‘pure tone’ over both octaves. I currently use a Howard low D and have gotten used to the high back pressure of this instrument. The Burke has very little back pressure so, I’m sure I’m going to have a small period of adjusting to the increased breath requirements.
Here’s a website with a crappy sound clip that doesn’t do the whistle justice:
Cristian , I have to agree with everything that Byll has said. My Burke Viper is a clear lovely whistle. It doesn’t have the haunting "cosmic drainpipe " sound that I get from my Overton , but , that’s not always the sound that I want from a low whistle. In addition , at least for me , piper’s grip is almost a mandatory on this whistle. Not a problem ! 
Have a Great Day and Fun Whistling !!
I have a Burke Viper D. It is a nice whistle. It is in-tune, blows easily, has five sections to allow for easy reach to the bell note. It is a bit on the quiet side, so it is not a whistle for outdoors unamplified or other situations where volume is needed. The tone is a bit on the pure side. Some like that, I find that it sounds better where natural acoustics provide a reverb or echo.
If this is a person’s first low D, I might suggest trying something less expensive to start (if budget is at all a concern), or something used. Low D’s are not for everyone. Being in Argentina makes that more difficult because shipping will be a significant cost no matter which low D is purchased.
Thanks for the info guys! 
I just received a soundclip via e-mail, and I have to tell that I love the sound of this whistle. I was looking for a pure sound, with a sweet not-forced second octave. I don’t need a loud whistle for now, as I’m playing mainly indoors.
I’ve made a couple Low D’s, but they require too much breath and sound quite forced in the second octave, so I wanted a good quality instrument, and as my sister is currently in Switzerland this is my best chance on getting one. Shipping to my country is not so expensive compared with the custom duties which are +50% of the the sum of the items plus shipping 
, so this is a good opportunity to get a good whistle. Won’t have it until January when my sister comes back though 
I’ll start to work on the piper’s grip now 
It’s the Burke you’re looking for then.
I don’t need a loud whistle for now, as I’m playing mainly indoors.
I’m primarily an outdoor player and in all honestly, out of the Low D’s I’ve played, there’s not really one I’ve found that’s ‘superb’ for outdoor playing. All are relatively quiet and, due to the lower frequency, just don’t cut, but that’s OK – kinda levels the playing field a bit to select by preference of sound.
Enjoy it!