Geisemann Aquaristic is known internationally for their uncompromising and high quality products as per european consumer standards, dominating the 'best of the best' niche in lighting fixtures for decades. However, this dedication has met an impasse in reef aquarium LED lighting: american consumers don't want premium quality at a premium price, and american aquarists make up over 90% of the aquarium LED market currently. What's Geisemann's answer?
Whilst other companies see no problem in providing american aquarists what they desire (terrible products at a low price point), Geisemann was quite obviously not happy with that option and provided an alternative that has recently been unveiled as the Teszla LED light. Obviously named honoring the great Nikola Tesla, the light is Geisemann's first serious foray into reef aquarium LED lighting; and one they were forced to compromise on.
To achieve the $499 pricetag required by the US market, Geisemann was forced to cut R&D costs, and thus the Teszla uses stock Cree emitters. Don't leave yet: if that were the end of the story I wouldn't be writing this, as 'just another cree led light' is hardly a reason to pen a post! Luckily for hobbyists, Geisemann chose the new made-in-Japan XM-L daylight emitters. While far from perfect for our application, they are most definitely an improvement in terms of spectral output and efficiency over previous Cree models.
The Teszla is equipped with the 5000-8300k version of the XM-L diode. It's definitely nice to see output beginning at 420nm rather than 440 or 450, but because Cree manufactures emitters for human eyes we still have the huge (and useless) peak at the 550nm mark. Luckily there is still quite a bit of energy in the 600-650 range, and a good spread to 700+ for the rendering of oranges and reds. The rest of the emitters are blue and royal blue XP-G's, and 2 "special" emitters (?), for a total of 20 emitters.
A full-fixture spectrograph would be nice to see, because the outputs could vary radically from the stock output, depending upon the associated electronics. Are the emitter choices for the Teszla Ideal? No, but not that far from it. Remember, this is a sub $500 fixture, not a common price point as far as Geisemann is concerned.
When emitter choice is taken out of the picture, the rest of the Teszla fixture is excellent. The usual quality Geisemann engineering shows in the fixture design in more ways than one. The fixture is designed similarly to a halide fixture to spread light in an even quantity at 120 degrees, as Geisemann avoided using individual emitter lenses to provide the wide, even spread. While depth penetration is understandably compromised, a 120 spread is on average the most practical. The fixture is made of powder coated aluminum, and has the classic Geisemann look. The Teszla includes a suspension kit out of the box, with the option to purchase a $49 mounting arm. The chips controlling the output to the various emitters were also made by Geisemann, so I'm hoping they took this opportunity to tweak the output of the emitters. Once again, I would like to see a fixture spectrograph!
All of the electronics were designed in-house by Geisemann, which is very nice to hear. More info to be released in the full review. Features include an automated lunar cycle (very useful), and the ability to separately control each of the three banks of emitters for color selection (not so useful, but a gadget US aquarists don't seem willing to give up). The Teszla is cooled via a single fan that is temperature-controlled, a nice touch. The Teszla consumes a total of 66 watts, so the emitters are likely being driven at 3w each, although Geisemann could have tweaked the operating voltage to improve output.
Geisemann did a great job with the overall design even when forced to compromise for the US market. When you account for the two year warranty and brand name, this could be one of the very few LED lights worth spending money on. I'll know for sure soon, as the light is shipping to dealers as we speak. I'll be toying around with my review unit so expect pics and videos in the coming weeks!