Echle RR25-16


Author: Karsten Hein

Category: Gear & Review

Tag(s): Loudspeakers

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Shortly after the turn of the century, some twenty years ago, the audio technician and car-Hifi store owner, Winfried Echle, came across the review of a Dynamic 16cm bass-to-midrange driver with Kevlar diaphragm when leafing through one of the last issues ever printed of the German electronics magazine ‘Funkschau’. The chassis was made in Thailand and, as it turned out, was difficult to obtain from a German supplier. This prompted Winfried to contact the Thai embassy in Frankfurt to establish direct contact with the producer in Thailand. When he finally received a response, it was to inform him that the minimum order quantity was at 100 pieces. Winfried took a deep breath and made the purchase. “I was feeling put under pressure, but what I should have done, would have been to place an order for 200 units instead.” he told me laughingly, “How could I have foreseen how successful these little drivers would become.”

His first serious bookshelf-size loudspeaker was of a two-way design, with a front-ventilated bass port that was placed in one corner right next to the tweeter. The passive crossover cut the tweeter off at 1,500 Hz and at a 6dB slope per octave. Early models featured a 2.5cm Peerless soft-dome tweeter, which Winfried ended up replacing with a Vifa XT-300/K4 ring radiator on later models. The ring radiator did not play as loud as the soft-dome tweeter, but it introduced a new sweetness to the sound and offered a more pleasant drop-off in the treble. The crossover parts, internal wiring, and wire terminals were of a high quality, and the pass port was fine-tuned to be as linear as possible, preferring tight control to the usual 60 Hz hump. Winfried spent some time listening, measuring, and adjusting the crossover parts and bass port until he was pleased with the result.

Showing his new prototype speakers to friends and visitors to his shop, some of whom were industry specialists themselves, Winfried received excellent feedback on his design and ended up selling over one hundred of these bookshelf speakers. In fact, he sold more speakers in the given price category than the local HiFi shop did at the same time. To the owner of the HiFi shop, this did not come as much of a surprise, as Winfried’s unique price-performance ratio even impressed his friends at Hessischer Rundfunk who bought two pairs of speakers for proper installation in their broadcast vehicles. But, was this just a lucky punch, or a replicable show of skills? Listening to the story made me curious, and I just had to find out for myself.

Ever since hearing about his monitor speakers for the first time, I was tempted to take them home with me for a trial run. But it was not until our impending relocation from Frankfurt am Main to Marne, Schleswig-Holstein, and when our weekly meetings in Aschaffenburg were slowly coming to an end, he let me know that he would actually be honoured if I still found the time to write a review. Of course, I did not have to think twice about this and brought along a large Eurobox for transport, into which the pair fit perfectly. On my drive back home, I contemplated which amplifier to test them with and decided that I would go with our Dynavox VR-70 tube amplifier, unless this would prove to be problematic due to some unforseen mismatch in capacitance or resistance.

I gave our EPI 500 floor-standing speakers a good listen and then set up Echle’s bookshelf speakers in that same position. The DIY stands I used had originally been designed for our KEF iQ series speakers, and they were made of sturdy PDF boards perched on spikes with coasters that were in turn placed on felt cushions for decoupling towards the ground. The finished stands weighed about as much as the speakers themselves and gave them a firm position while preserving their ability to sufficiently free themselves from the floor not to excite ghastly resonances. With the Vifa tweeter being mounted off axis, I was puzzled for a bit whether to have the tweeters on the inside towards the listening position or to rather have them on the outside, away from the listening position with the bass port on the inside. I decided to listen to the set with the tweeters on the inside first.

The resulting musical image was accurate yet somewhat thin-sounding. The center image was super sharp, and voices seemed slightly thickened and throaty with an alluring touch. There was lots of bass texture, even if low-bass extension was not great. The speakers performed in a well-behaved manner with a sensible top-end. The midrange was insightful and homogenous. Piano keys sounded warm enough but were lacking some of the treble bite and bass punch. On occasion, I noticed a little time-smear and could sense more than the usual sibilance. Looking at my setup, with the vertical radiation axis of the speakers merging about 50cm behind my head, I could see that I had brought the tweeter coils relatively closer to my ears than the woofer coils.

Since the woofer coils were usually positioned deeper inside the speaker cabinets than the tweeter coils, swapping the left and right speakers to position the treble outward would help to correct this issue by increasing the distance between the tweeter and the ears. The result was less time-smear and sibilance and an increase in stage width. The midrange remained the strong point with accurate tonality. The initial lightness of sound had disappeared. The result was vocal credibility and a kind of no-fuss reporting of musical events. The term understatement came to mind, an impression that was even enhanced by their their ample use of build-depth rather than height or width.

From Nick Cave’s live-album ‘Idiot Prayer’ I then changed to Boris Blank’s studio album ‘Convergence’. I also turned up the volume from Cave’s natural-sounding voice to moderate disco. Boris Blank has been a long-time favourite among tech-minded people, and on its basis the speakers could show their ability to keep the separate layers of samples apart. I was impressed with the insightful positioning of bass-events from left to right and from top to bottom as well as the lack of tweeter aggressiveness I would normally have expected from smallish speakers playing loud music. I did notice, however, that the higher excursion of the woofer of +/- 8mm did lead to to a certain breathiness in the treble. I am not convinced that the Doppler effect would have been as pronounced if the bass port had not also been positioned between the tweeter and the listening position.

I enjoyed listening to these speakers being played loud, especially because their treble was a little more forgiving than on our other models. Michael Patrick Kelly’s live album “ID” came to mind, and the speakers did not disappoint in terms of speed, agility, and, to some extent, even dynamics. The kick drum sounded hard and firm. These loudspeakers would work equally well playing Rock music and Jazz, and that combination was not all too common. Rock music requires for the music to be kept together rather than taken apart, and this was certainly the case.

To round off my exploration, I put on some Norah Jones. “Feels like home” was presented with musky vocals and amber keyboard notes. It sounded at once exciting and spacious as well as refined and well-proportioned. The soft top end that had served so well when playing the speakers louder here resulted in a slight lack of crispness in piano notes. In the end it seemed as though we cannot have it all, or at least not in the still affordable price categories. I wonder, how many of us would get up to tweak the sound coming from a real live event, if we were given the power to do so. As around speakers and for serious listening Winfried’s speakers were certainly able and enjoyable tools. When it came to mixing music and discerning listening, on the other hand, the somewhat relaxed treble presentation might make problems in this area seem less dramatic than they really were. For monitoring vocals, these speaker were truly excellent.


  • Type: 2-way bookshelf speaker
  • Speaker principle: vented cabinet
  • Crossover 1,500 Hz (@6dB per octave)
  • Application: entertainment, monitoring
  • Tweeter: 25mm Vifa XT-300/K4 (Tymphany)
  • Tweeter principle: ring radiator
  • Bass driver: 16cm dynamic, Kevlar diaphragm 
  • Dimensions: (H) 320mm, (D) 350mm, (W) 210mm
  • Country of manufacture: Germany
  • Designer: Winfried Echle
  • Year: 2002
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