This review page is supported in part by the sponsors whose ad banners are displayed below
The tube’s upper end aka plug is made up of a damping material which blocks only the highest frequencies. This functions as a quasi mechanical low-pass. It remains partially transparent to the frequencies close to the crossover value. That is claimed to create a more homogenous blend with the midwoofer. Enter the space ship. Its half disc’s belly is covered with felt to reflect just the lower portion of the tweeter’s coverage band whilst absorbing the upper. Heolo explains that this prevents a leaned-out midrange and supports more sonorous vocals. At this point the Gamma has clearly outed itself as not being radically omnidirectional.
Final design details are two toggle switches above the biwire terminals which can raise output between 2.5-3kHz and 8-15kHz respectively by 1.5dB; and a rather large bass reflex port that is reminiscent of classic Onken designs and said to exhibit high self damping similar to a sealed alignment for quick well-defined low bass. By now 'twas high time to test high concepts in my listening room.
In my room the Italians did in fact exhibit a rather broader sweet spot than my Thiel CS 3.7 which are quite intolerant to anything but a particular seat. Yet especially during complex passages I felt that the Gamma performed a tad better sorted when it was faced straight out rather than being toed in sharply at the listener. Last but not least the concept of this treble solution includes the thematic of phase coherence. Due to the recessed tweeter’s close motor proximity to the acoustic center of the midwoofer, the German importer claims "time-coherent dispersion for nearly all listening positions which causes the impulse-correct rendering of transients".
I’m admittedly fonder of music far removed from Smooth Jazz. I fancy stuff which, under higher SPLs, takes off. Here a song like "Dancing Choose" from New York’s electronica-avantgarde-soul-postrocker TV on the Radio and their 2008 album Dear Science isn’t the end of the heavy stick but it does already warm if not boil the blood.
Here I wanted to challenge the petite Heolo Gamma which for a floorstander is already somewhat challenged dimensionally. Would this rock out? With certain qualifications it could as I’ll explain. Yet the first audition rather got fixated on treble performance.
Be it the left-channel presence of the hi-hat throughout the cut or the subliminal easily missed HF noise reminiscent of an electronic alarm which begins to float etherically above the rest in the middle of the song… the upper frequencies were strongly there, i.e. clearly not dimmed though not artificially pushed either.
This pleasing unforced nature of the upper registers felt less like ‘box sound’ than I was used to even from my significantly costlier reference speakers. To nip presumptions in the bud, this quality wasn’t synonymous with fluffy room fill as the word omnidirectional might suggest. Au contraire, it was highly defined and exceptionally image or location specific.
