I found this thread just now (2 years later).
We sold original HECO speakers made in Schmitten in my dad´s brick-and-mortar store back then in the 60ties to 80ties. Later on the Visonik Davis - versions, made in Berlin. Both series were really good. The originals, especially the P - series, were everything as good as e.g. Braun, the Visoniks could easily compete with contemporary Canton speakers. I had Visonik David 100 im my Renault R4, together with a Pioneer system. Great!
Several years ago I could get Heco P4302 SL from my sister. They were knackered. But They were fixable. I found exactly the dome-type tweeters and midrange speakers I had in my former Braun L710/1! No wonder, Heco made them from Braun ... It was easy to adjust the membranes and voice coils of the dome-types in the magnet so they stopped buzzing and were glass-clear again. A recap of the crossovers with foil-types and swapping 20 % tolerance cement resistors with 1 - 2 % metal film types did its job. These speakers are revealing, true sounding, fun! Only the level (not the quality) of the bass sometimes left the desire for more. So I - after a long search - could get the bigger sister, the P5302 SL, three days before. They sound really good - even with the original crossover. Of course they will get the same treatment with modern parts. I love these speakers!
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