Hi ,just joined today, I’m from Romsey in Hampshire in the Uk ,noted your article, because I am in the market to buy a low whistle in C have been playing a low D for a few years now ,but have just formed a little group of people and included in the group is my partner who plays a lever Harp, and a lot of Her music is in C so thought I might give that key a go the low D is a chieften which I am happy with any advice on a C would be helpfull
Hi iedapus, welcome to C&F, and the exciting world of whistles.
I play a Chieftain OS low C, and a Howard new version head with diy C tone tube. I enjoy both. They each have a differant voice so that comes to personal preference.
(Tommy beat me to the “submit” button! 
)
I have had three low C whistles - Dixon, Chieftain OS and Burke. I play the Burke. I sold the Dixon and Chieftain. Ok, I also have a DIY shower curtain rod tube on a Howard head. If you already play a Chieftain low D, get a low C Chieftain. It’s a fine whistle. I just liked the Burke better.
Feadoggie
Are we obligated to tell where a DIY tone tube originated from? Am I going to receive an email from the DIY Czar, or would it be the Science Czar. 
I play low whistles by two fine makers: Mike Burke and Colin Goldie. Since my friend Dennis already mentioned the Viper, let me put in a suggestion for a Goldie Overton. Colin makes low C whistles in two styles - the small bore (like his low D), and the standard bore. Both are called Baritone C whistles. Colin crafts superb instruments, which marry solid intonation with excellent playability. And then, there is that sound… At this point in time, Colin has a small bore low C or two, that may not be spoken for… With either the Viper or a Goldie, you cannot go wrong.
Best to you.
Byll
I hope we’re not obligated to tell. I honestly can’t remember at this point who originated the idea. Auldtymer’s is setting in. It’s been some number of years now. Sure wasn’t me. Was it you, Tommy? I was making low whistles out of shower curtain rods probably motivated by Dennis Havlena’s web pages. http://dennishavlena.com/low-d.htm My shop wasn’t well equipped for making whistle heads at the time. My results were not stellar at that point. Then someone, probably here on C&F, mentioned that the Howard head fit a 1" shower rod so a) out came the hacksaw and b) off with the Howard low D’s head. (crack and flash of lightning) It’s alive! 
More bodies followed. Thankfully I was able to purchase a couple second gen Howard heads so the original Howard low D lived on. That’s my story and I’m stickin’ to it. I’d hate to get on the wrong side of the Czar, any Czar.
Oh, and Byll’s right to mention Colin Goldie’s Overton low C’s as well. Colin’s work is certainly among the most respected of all whistle makers.
Feadoggie
Hi everybody that offered me advice on a low C whistle it is all very helpfull, I thank you all very much, from whats been said I think Iwill investigate the overton in a little more depth.thanks again
I’ve got a big bore low C Goldie with large holes. It’s my favourite whistle. I can just make the stretch. The back pressure and the solid tone are perfect plus it has that sound.
I have a Howard low C which I really like very much.