Acme whistles/ Dog whistles?

Has anyone had any experience of using a dog whistle with an older dog who is loosing their hearing?

I spotted an acme whistle in a shop the other day, googled them when I got home and found they did a purple one (purple is my colour!) so I ordered one today.

i use a whistle for many dogs for recall

Have you found the higher pitch of a whistle such as the acme works better than a voice whistle?

My collie is 13 now and going a bit deaf, she can't hear my whistle or voice much anymore especially when it's windy, I am hoping the whistle will help, if not at least my retriever can learn some whistle commands

i just use a referees whistle

I also use a whistle for recall and stop. The one I have is the Acme 210.5.

Definately better than voice or human whistle and Bodi still responds well to the acme whistle of the windiest of days.

I have an Acme 211.5 and it' pink!

I use it for recall and stopping my dogs.

My whistle is higher pitch than the 210.5, but this is only because my OH has his dogs trained to the 210.5 and it's easier for us to train in the same area with different whistle pitches!

I find it such a valuable tool, as my dogs can't always hear me, it gets really windy at my house!! And for shoot days, as I work my dogs!

Just a general plea - please be aware that these high pitch whistles can startle horses badly. My neighbour used one right behind our hedge and my wife was nearly thrown off her young horse

Bit of an update.

Got my whistle last week and it seems to work, my collie comes bounding up to me when I use it

Also works on my horses and they come cantering up the field for their dinners with a blow of the whistle