|Top row (Left to Right) : INS-BS top side, bottom side|
Bottom row (Left to Right) : INS-CF black side, INS-CF silver side, INS-BD Black Diamond Hematite, INS-SQ Smoky Quartz
Oyaide's INS-BS is a small chrome plated brass footer (35 mm diameter and 15 mm in height) with a recessed hole on one side, and a carbon fibre disc on the other side. The recessed hole accepts the INS-CF carbon fibre disc. Oyaide also advertises that the INS-BD Black Diamond Hematite disc or the INS-SQ Smoky Quartz disc may be used in substitution for the INS-CF.
In the case of the INS-CF, the carbon fibre disc is black on one side, and silver on the reverse. This actually gives the INS-BS a total of 8 ways of usage, with the footer used with the inserted disc facing upwards or downwards, and with INS-CF either used with the black or silver side.
However, after much liberal experimentation, I was unable to fit the INS-BD or INS-SQ reliably into the INS-BS. Either excessive force had to be used, or the insert was unable to fit at all. Rather disappointingly, most of the evaluation was therefore made in respect of the INS-BS with INS-CF and the INS-SQ and INS-BD had to be used in isolation.
Technical glitch aside, the INS-BS and INS-CF proved to be a highly versatile and effective tuning disc. Using the pair facing upwards and downwards sounded quite different. I preferred the set with the INS-CF facing upwards towards the component.
Using the INS-BS in isolation brings a sharp increase in focus and energy. I found this to be overwhelming with explosive dynamics albeit with an increase in sibilance and harshness. Inserting the INS-CF with the silvered side upwards balanced this out with a slight smoothness and increase in bass bloom. Reversing the INS-CF with the carbon side upwards increase the density of tone with a slight loss in dynamics and focus.
Using the INS-SQ was interesting to say the least. The overall balance of a system can be tuned using these smoky quartz discs in the most illogical of places, like on top of speaker cabinets, the component chassis , etc. Use is limited only by the boundaries of your imagination.
The INS-SQ further improved focus, texture and the length of decay, with a slight lightening of tone. The INS-BD on the other hand did not quite agree with me. It made the sound overly sharp and phasey-sounding.
I enjoyed the INS-BS / CF thoroughly. Use of crystals is not totally alien to me, with my prior use of Acoustic Revive products like the RTP-6 and QR-8, but the INS-SQ still delivered some surprises. I highly recommend this product in light of affordable pricing, versatility of use and good performance. However, I would like to see Oyaide address the tolerance issues I faced with using the INS-SQ and BD.