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Audio Replas TS OPT300HR: Audio Replas is a recognized Japanese firm specialized in audio cables and accessories. In particular, the company has invested in developing materials for different purposes. One that Audio Replas is especially fond of is high-quality silica glass. Ultra-hard quartz crystal by itself is a suitable anti-vibration material because it resonates well outside the audible range of frequencies. Audio Replas has further improved the material and baptized it "High-Response Super High Purity Quartz Crystal" (HR Quartz). This new anti-vibration material is said to have a unique effect on the sound quality, including a better soundstage, higher S/N ratio and so on.

This is what the manufacturer says about their TS OPT300 HR turntable mat: "The platter sheet for a vinyl disk adopts super-purity silica glass whose acoustic velocity, vibration processing speed and capacity are markedly superior to any other material. The platter copes effectively with a wide range of distorting vibrations of a vinyl disk taking advantage of its insulator effect to result in better sound quality." What I think this says is that the AR platter sheet is simply a piece of material—super-high purity quartz—with certain favorable physical stabilizing characteristics and that’s is. The sheet is 4mm thick (VTA needs to be adjusted) and weighs 610 g. The spindle hole is 7.4mm and around it there is a 1mm deep 105mm wide depression.

This product provided a harder case for assessment in terms of sound quality. Not that there was no effect—there was and just like with the URSR I felt it was positive—but it was far more subtle and there certainly was no crisping or brightening. The best overall description I can think of would be to say that the sound became calmer, more stable and quiet. In a word, smoother.

But again, the ’improvement’ was of a more hidden kind. I couldn’t convince myself with equal readiness that the effect was really there. Rather than perceiving the effect I sensed it and sensing does not provide similar evidence for justifiably knowing things. I definitely should have spent more time trying to understand the true impact of this quartz sheet. A couple of hobbyists here in Finland tried to measure its anti-vibration effects and discovered some supporting evidence that the mat works as claimed. But evaluating the sound with one's ears of course is a different task altogether.  

Pure silica is expensive and the price of the AR platter sheet, circa €4000 in Europe and $6000 in the States, certainly reflects the price of the raw material.  Still, the price is very steep. I feel inhibited to recommend the mat even though my honest feeling was that it did create promising results. There could be other combinations of budgetary (non)constraints and ambitious turntable systems that might justify this purchase.

Oyaide HS-CF head shell:
Detachable head shells with SME type 90° pins—so-called universal head shells—are relevant only for tone arms which accept them. Owners of the Technics SL-1200 are veterans at using detachable head shells and so are the crowds that fancy vintage SME, Ortofon, Audio-Technica etc. wands. Modern EMT arms also accept SME type head shells. And they are practical. You could stock one for a mono cart and more than one for stereo pickups depending on the music style, record label etc. True analogue enthusiasts have multiple cartridges to dig out the best from their record collections. Head shells in the past were offered by Pioneer, Technics, Ortofon, SME, Thorens, Sony, Philips and many others. Dynavector, Yamamoto, Audio Replas are some of the modern contestants.

When a stylus ploughs the groove, mechanical vibrations not directly related to the music signal are generated. These vibrations carry into the tonearm and return back into the cartridge to modulate the signal with negative consequences. The better the head shell, the more effectively it kills these vibrations and isolates the cart from the arm. A good head shell thus embodies within its design an anti-vibration structure. It allows the cart to be firmly connected to it;  makes a firm connection to the tonearm; and sports decent wiring and connectors.

The Japanese Oyaide firm was founded in 1952. Today it manufactures a wide variety of audio accessories from cables to connectors and wall outlets. Oyaide's HS-CF head shell is made of special carbon fiber reinforced plastic. It weighs 12 grams and is 4mm thick which comprises 17 layers. The manufacturer believes that choice of material and construction absorb vibrations without changing the natural resonance behavior of the tonearm system itself. The fixing screws are made of aluminum and so is the socket with resin press fitting inside. The pins are gold-plated brass and the lead wires are 5N pure silver with double-layered silk insulation. The rhodium-plated lead tip is made of phosphor bronze.

To compare the Oyaide head shell with other,s it would have been more convenient and appropriate to have several samples of the same cartridge, one in each head shell. In my case, I simply removed the same Denon DL-103 from one head shell to the next and listened. Perhaps because of this test procedure, the listening results were rather modest. For instance, as compared to the Audio-Technica AT-LT13a, a fine but not extraordinary head shell, the difference in the sound was minor, with nothing major in HF performance. Even relative to basic shells by Technics and Pioneer, the sound with the HS-CF didn’t deviate much. But I wouldn’t worry about this result. First, the type of differences I associate with changes of head shells are such that they are bound to expose themselves only over a longer periods of time, not quick test sessions. Secondly, the underlying theory of head shell importance is so sound that at least I will always resort to the best possible one available to me. €200 for a well-made head shell such as the Oyaide HS-CF then is no bad investment.     

Audio Replas website
Oyaide website
Sound Fountain website