Hi, welcome to the forum.  Yes this appears to be a high pitch instrument.  At one time instruments were made for either low pitch (A=440 Hz) or high pitch (A=457 Hz).  Those two frequencies are about 1/4 tone apart.  If a low pitch and high pitch instrument both play an A at the same time, the result would be annoyingly dissonent.  The low pitch approach finally won out (in the 1930's maybe), and since then, all instruments have been low pitch.

The bad news for you is that this high pitched horn cannot play in tune with any other low pitch instruments, and there is no known way to correct this.  Therefore, even though you have a very nice horn (valuable if it were low pitch), it has almost no value because it is high pitch.  I do not know what mouthpiece came with this horn, but it is possible that the mouthpiee is worth more than the horn.  I would guess that the horn is worth less than $150 on the market, and would be very difficult to sell, since players would avoid it.  You would have to find a collector who is interested in that specific model.
 

It seems that most of the H High pitch instruments were sent out of the country. I have heard it called the European tuning also. I agree, the value is low. It can be played alone and only those listeners with perfect pitch would ever know. Put it on Ebay and list it as a High pitch. You will sell it. Start the bidding at 85 bucks.

I have a number of vintage Conn altos. I would pay 85 bucks knowing what it was if I ran across it. Looking at the wear on the thumb rest, it has been played a bit. Probably in its day of the 1920s.

Good Luck

I would buy it for parts and the case which appears to be in better shape than mine. Does anyone know if keys and such on the 'H' models would fit the "L" models?

Hi,
Is this horn is still available ?


Regards