Buying your first Vienna horn is something of a journey into the unknown for most horn players.
Assuming that your are a competent double horn player you will be equipped to try the horn out, but may be unsure of what to expect.  
Outside of Austria, the Vienna horn seems shrouded in mystery. Here is some advice that should help!

Playing the Vienna horn

Moving from a double horn to a Vienna horn you should find the horn better than the F side of a double horn.  The particular design of the Vienna horns benefits from good use of air, and confidence in attack.  It may take a while to master this, and perhaps the advice of a good teacher.  Practise driving lots of air into the horn.  This will result in a good tone, and greater accuracy at all dynamics. 

New Vienna horns

I would suggest consideration of Haagston, Jungwirth, and Yamaha Vienna Horns, 
and Breslmair, Moosewood, and Windhager Vienna horn mouthpieces.

The crook and the mouthpiece

The crook is rather like a detachable leader pipe on a double horn. Different crooks can change the character of a horn dramatically. If you are choosing a crook separately ensure that the horn and crook combination can play in tune, that the entire range is supported, and that it fits well onto the horn receiver.

The mouthpiece dimensions differ from the double horn.  A deeper cup is often used, and the backbore is more parallel. 

Contacts:

Alois Mayer - Haagston Vienna Horn maker
www.haagston.at 

Andreas Jungwirth - Vienna Horn maker
email- jungwirth-horn@aon.at  
phone +43 298 533 032

Votruba Musikinstrumente GmbH - Yamaha dealer in Vienna
www.votruba-musik.at

Franz Windhager - mouthpiece maker
www.whf-mouthpieces.at 

Breslmiair - mouthpiece maker
www.breslmair.at

Tom Greer - Moosewood - mouthpiece maker
www.hornmouthpiece.com 

Used horns

Occasionally used Vienna horns are seen.  Rather like used cars, each horn should be judged on its own merits.  Vienna horns are not mass produced, and each one can be slightly different.

Bad horns

Not every horn made using a Viennese wrap has the potential to be used by the Vienna Philharmonic orchestra.  Some makes of horn vary from sample to sample to a significant degree; there are bad Vienna horns on the market (new and used), and a novice horn player may believe the fault is with their playing; do not make this mistake.  A good Vienna horn is better than the F slide of a double horn, high register accuracy is achievable, albeit a bit scary at first. If important notes cannot be sounded, then think very carefully before buying the horn. (alternative fingering may help).  

Price (a rough guide)

A top quality, new Vienna horn, will cost between €5000 and €6300 (euros).

A quality used horn in good working order will generally cost between €2000 and €4000 (euros).  

Old horns in need of servicing or restoration, and collectable horns in poor condition may only cost a fraction of the above to purchase.  Only after repairs will you really know if these horns can work well.

info@svh.org.uk