The Audio Eagle - budget amps & speakers & more

Early January, Joe had the idea to invite some of his friends to a listening event at his place to audition some affordable amplifier creations and to see if musical pleasure can be found without mega buck investment.

I was happy to join when Joe invited me, not only because the idea was a great one, but also because he's really talented in cooking great food (he has a lot of practice due to his 4 kids) and audio gatherings at his place always incorporate a delicious meal ;-) The other friends who joined the audio session were Michael Joncic and David Haigner.

The intention was to evaluate how much listening pleasure can be achieved by using affordable audio components (DIY CD-player, different DIY amplifier concepts and a pair of well designed loudspeakers) in one system. The source used was Joe's budget CD-player design around the Sony Playstation PS1 (with AZ11 tube rectification and 37 triode output stage).

For amplification, we tried four different DIY amplifier designs:
Joe's version of Hiraga's famous "Le Monstre" with a lot of iron in the power supply (instead of the common solid state approach of a lot of capacitance via electrolytic caps), Joe's "El Cheapo", a SE tube amp with a bit of negative feedback (4 dB) using EL84 power tubes, a tube pre- / flea watt power amp combination around the PL82 output tube based on a Götz Wilimzig layout and built by Wolf Andrejkof one of our audio friends (who unfortunately couldn't take part in our session) and last but not least, a Class A impedance converting amplifier (without gain) built by Michael Joncic, another audio friend of ours. Due to the latter "zero gain" design, we used the "Willimzig based pre amp variant" with all the amps to make sure that we could listen with similar-to-equal output levels.

The loudspeaker used was a prototype version of David Haigner's latest reflex-horn design named Rho, which is a time-aligned, impedance linearized two way floor stand model with an efficiency of about 91 dB and moderate cabinet size. For two of the amps - the "El Cheapo" (1.5 Watt) and the "Wilimzig variant" (close to 1 Watt) - the efficiency was definitely to low (they would need about 100 dB to really shine), but listening with low to moderate levels gave us an impression of the amps' signature.

Interestingly, the musical qualities of all 4 amps within this set-up were very high and one could wonder if paying many thousands of euros for high end audio equipment is worth the difference in musical pleasure. (A tough question, which every audio lover has to answer for himself; for some audio equipment gems it's possibly worth it, but they are a rare species...)

My personal favorite was Joe's "Le Monstre version" (due to the amount of iron in the power supply, this is a really heavy amp, though), which sounded open, clean and liquid, with superb mid range followed closely by the "El Cheapo" and Michael's "zero gain" impedance converting amplifier tying for second place. The "Wilimzig variant" combination was also wonderfully musical, but the power limitations could be heard the most with this combination. Trying the "Le Monstre version" and the "El Cheapo" without the pre amp, by connecting the CD-player directly to the amplifiers input improved the musical qualities further and in this configuration the "El Cheapo" was - despite the low output power - the winner. The bass was so fast and liquid - full of verve - the mid range was colorful and the top end wonderfully open, superb...

The "stars of the show" to my ears were David's Rho speakers (prototype version). They do so many things right, and over an astonishingly wide frequency range, that you wonder how it is possible given the size and the scheduled asking price (starting from approx. EUR 2,500 pair, depending on cabinet finish). The final product should be available for purchase later this spring and will cause quite a stir in the loudspeaker market, I'm sure.

CD source: Joe's pimped Sony PS1 (AZ11
rectifier on ground floor and tube output stage
with 37 triode above)

Joe's "El Cheapo" tube amp (with James output
transformers)

Photo courtesy of Josef Aigner

Photo courtesy of Josef Aigner

It was a fun Friday evening with great music, talks and a superb goulasch. Thank you Joe for setting this up!

For questions regarding Joe's great sounding amps feel free to contact:
j.aigner "at" igk.co.at

For questions regarding Michael's "zero gain" amp feel free to contact:
mjoncic "at" sbg.at