Actually, the one I have is a Wheatstone. I got it from Herrington in Texas. Since he is a builder of concertinas (albeit anglos) I believe it is fine as far as tuning; It is in tune with itself. It's about 50 years old but it sounds good to me. I just didn't realize the tuning difference between instruments.

I was very lucky to get my Wheatstone because I had just begun to look. Herrington happened to have taken one in on a trade.

Margarita