I often get the question 'which speaker do you recommend, which work well with your amplifiers?'. My answer always is: Haigner. This is a small loudspeaker manufacturer situated in Vienna. David Haigner, the man behind the company, grew up in a family of musicians. But instead of making music, he chose to concentrate on the reproduction of music for his profession. He is in this business for well over 20 years.
Have a look at his web page for details on each model. All of his speakers work very well with low powerd tube amplifiers. Their linear impedance curve is an easy load for them.
Even his smallest speaker, the Rho is a top performer. In fact I'm using this speaker myself in my small system. I usually use it to audition new amp developments. It has all it needs for this and reveals every difference between the amplifiers and preamplifiers I make. David specifies 91dB sensitivity. This seems to be not too sensitive at first sight, but David is very conservative with his numbers. I use low power SET amps with this speaker and they work even well with a 3.5W SE 801A amp if you don't need ear shattering levels.
The speakers were driven by a Stereo 801A amp of mine which is sitting on the floor between the speakers. It uses an external power supply which is hidden behind the left speaker.
Preamplification was done by my EC8020 LCR phonostage and 801A directly heated triode linestage. Both powered by external PSUs which can bee seen behind the right speaker. The Tau was able to play at remarkably loud levels with the 3.5W of the 801A amp. This system was a perfect match and we got excellent feedback from the audience.
Vienna Vibes event in summer 2010. He held an amazing lecture. Among other topics he talked a lot about room acoustics which is one of David's fields of expertise. He gave astonishing insights into this topic. The room was jam packed with people. Although that particular day was very hot and the room had no air condition, nobody wanted to miss a word and everbody stayed until the end of the lecture. And this dispite the fact that David did overun the given time slot massively well into lunch time.
I'm glad to personnally know David and have him as a friend. He is a very nice person who has a lot of knowledge to share. And of course he builds marvellous speakers.
David not only develops and sells his own speaker models. He also does consulting and custom developments for specific needs. He is also doing acoustic treatment of rooms and halls. Many public buildings like churches and townhalls, but also dance clubs have been acoustically optimised by him.
As all of David's speakers the Gamma matches very well with single ended triode amplifiers. The sensitivity is specified as 98dB/1w/1m. As with all of David's spec's this is a conservative measurement. The gamma will play really loud with a 3.5W amplifier. It is even suitable to be used with a flea powerd 45 amp.
If you have not heard them yet, do yourself a favour and give David's speakers a listen. You will be up for a surprise. Contact data can be found on David's website.