Rerurn to Romy the Cat's Site

The Heil AMT drivers are well known in audio. There is a cult of people who follow them and they swear that Heil drivers are like nothing else. The Heil drivers were made by ESS, by Scandinavian, by German’s pro audio and by Russians. The do use deferent principle for sound reproduction (I will not describe it – it well described out there) and do have different type of sound.

http://www.goodsoundclub.com/pdf/heil.pdf

I experimented with Heil in beginning of 2000s and although I saw a lot of very interesting and useful sonic characteristics in Heil I did found them absolutely unusable for any more or less serious application. Nevertheless, since I’m nowadays in my typically-crazy “tweeter mode” I decided to give to the Heil one more try.

I had two Heils. One pair is very small that I took for some kind of speaker 15 years ago. Another pair is the largest AMT-1A, takes from the biggest ESS. The smallest Heils sounded very dead form all dimensions and has sensitively at sub 80dB level.  The biggest Heils were the matter of the different conversation.

Heil Air Motion Transducers sound very interesting. They remove any defects of HF reproduction out of Sound. Even time misalignments, overly bright microphones or HF clipping become practical not annoying. They literary problem free and very addictive solution for many nasty thing in HF. The biggest Heil is 100dB sensitive and it is approximately what I got from them. Melquiades drove them well at ~8K crossover.

Nevertheless, listening the Heil for a few seconds I instantaneously recalled the feelings that made me to discard them for the first time. The problems are that Heil makes all HF to sound absolutely alike. Heil has own very specific “generic HF signature” and it inescapably inject this signature to absolutely any HF note that Heil tries to reproduce. The very same “common Heil HF denominator” is getting created in each single tone of ANY orchestra, in each single inflection in EACH single, in each musical instrument and it become superbly annoying. As soon I “got” a reference to this tone then it so followed me that there were not other options then to trash the tweeter.

I think the problems is the in the Heil transducer has ribbons that are cocooned into a plastic “waved envelops”  (Polyethylene initially and Mylar later on) and I feel that this creates the Heil signatures. The ribbons are not shaking free but the “handled by” the plastic wrappers that severely colors sound by with that “commonly honey” influence. It is not surprise that cleanness of this plastic wrapper or even smoking in the room severely affect the performance of the Hail tweeter.

Can a driver that produces a “Generic HF” be used for audio installations where the purpose of playback is to make audio to “discriminate the differences”?  The answer is very obvious…

Rerurn to Romy the Cat's Site