Sakura Systems OTA Cable Kit

Slawney,

I agree with you that OTA can be tricky in a phono cable and that using an additional shielding can be a value added. My findings also correspond to yours in respect of the lenght being an important factor when used as phono cable. In my particular case, I am using it in a shortish run (50cm) and without shielding.

Actually, Kimura was surprised when he heard that I am using it as a phono cable as well as it was not the original intention for this cable. Only better solution I heard so far in my setup was the integral run of wire from cart to PhonoCube (with part going out from tonearm being shielded), but for reasons of me a) changing wiring of my tonearms (other than under b) frequently b)modified Koshin 801 I am using at the moment would not allow for a rewire (well, maybe it would but it is a brand new one and I would hate to mess around it as yet). Besides, I just love it as is. :-)

Fortunately (otherwise it would not make any sense to discuss this cable as anything even worth mentioning and not something extraordinary) these occurences are not present when used as digital, linelevel interconect nor as a speaker cable. Actually, (although I have not used specifically Shun Mook shielding), my experiences with shielded OTA in a non-phono cabling are not very positive.

Have you tried it yet in your digital setup or between preamp and your VAIC's and/or speakers?

Best regards,
Sead

p.s. Did you get my mails? I sent them from 3 accounts, just in case. :-)

I would never twist the OTA cables, even in the 5" distance. The degradation in sound occurs in any kind of twisting. They have to be free and loose in order to achieve the best performance.
Ivo

Last night I proceeded with a second, more radical OTA phono cable experiment.
Purpose: the aim of the experiment was to bypass the Simon York output connector plate/bracket (fitted with insulated gold-plated RCA phono sockets) and connect the Simon Yorke tonearm wiring to PhonoCube via an extremely short OTA bridge.
Apparatus: Two OTA phono cables were made up anew. The RCA plugs were positioned on one side; the other side was sculpted/crimped into receiving pins for the SY tonearm wiring clips, taking great care not to tarnish the OTA wire with finger contact. The total length of these phono cables are 4.8 cm measured from the tip of the OTA RCA plug to the free end of the cable. (Imagine an even shorter length of the pre-made OTA RCA plug/wire assemblies that are now packaged in plastic envelopes with the kit.) The PhonoCube was positioned 3 cm away from the SY 9 TT and the SY tonearm wires were clipped to the end of the OTA pin leads, always being cautious of the free-standing nature of PhonoCube.
Observation: Sound quality was even more immediate, dynamic, and faster than the 25 cm OTA lengths I used in the previous experiment. Instrument positioning, focus and outlining was the precisest I have ever heard, and the tonal balance was (and I mean this) utmost neutral. Sound stage was even further extended. The equipment all operated flawlessly, and no difficulties were experienced with RFI.
Reflections: At this point, OTA's main role is to provide a minimal hook-up point for the SY tonearm wire. The comparative lengths (about 50 cm of SY tonearm wire and 4.8 cm of OTA) make it clear that, if cable contributes to sound, then it is the SY tonearm cable that is the major contributor. This internal tonearm wiring is 0.60 mm silver plated copper wire, sheathed in a p.t.f.e. (Teflon) coating. Simon Yorke insists that the phono cable should be of an equal or larger gauge than the tone arm wiring. I do not know why it is such a critical factor that the phono cable be larger than the tonearm wire, but it is, at least for him. However, OTA is 0.20 smaller. Nevertheless, I do not think that this causes the electrons in the SY tonearm wire to slow down when they reach OTA. :-) I can also imagine a further step to this phono cable experiment. With the goal of replacing the SY tonearm wiring altogether and the four clips holding it now to OTA, use an integral run of OTA from cartridge to PhonoCube input, like sead mentions. In this case, I wonder if it would be best to strip off the protective tubing of OTA and Teflon coat four 50 cm lengths of the OFC wire (without any silver-plating). (I got a little lost during the discussion of lacquers on this forum, can anyone tell me how to coat OTA in p.t.f.e. Teflon? or to silver-plate it?) Factors such as sead mentioned with his Koshin 801 tonearm make this project equally difficult with the SY tonearm: I would need to obtain a second SY tonearm. Multiple tonearms are not included, and the one I have is sealed to make tonearm wire replacement impossible. Of course, I could stick to the tonearm I have and run OTA tonarm wire strands outside it... but this would not be as good, mechanically, electronically and cosmetically. It would surprise me if OTA used in this fashion would be an improvement over what I now have, given the superb quality of the SY tonearm wire. However, OTA has a way of astounding you.... A few additional points: twisting the previous 25 cm runs of OTA was not sufficient to prevent all of the RFI and compromised the sound quality slightly (tone was choked, closed off, there was less bi-partite stereo separation, and more line noise and hum). Also, the excess axial force when using twisted strands acted on the PhonoCube input jacks, and I thought this would adversely affect the units longevity, so I disconnected it. I now use the untwisted 25cm runs to connect PhonoCube to the preamp. The idea is the same as the 4.8 cm bridge I just installed: the shorter the run of OTA the better. In fact, in every case when I have used OTA as an analog hook-up, I liked the shortest possibe alternative the best (which is not the case with every cable I have used). Furthermore, short runs break in faster. As far as OTA not being designed to function as a phono cable, I say: listen with your own ears. Once I got it down to 25 cm. it outperformed by a large margin the reference cables I had used in the past. Decreasing it to 4.8 cm brought out the last refinement in focus, neutrality, and speed. But this will not be possible for people with large phono stages (of course, they can go out and buy a smaller one :-) IMO, getting it down to 25-30 cm is sufficiently rewarding. I know that there is a gigantic difference between that and a 1.0m run of OTA (which is a gigantic difference to a 1.0m run of Ortofon, Fadel Art, et. al.). The difference between 25 cm and 4.8 cm is not as gigantic. I even wonder if record producers ever imagined that their recordings would be listened to in this way: gated snare drums shoot by so fast through a 4.8 cm run of OTA that you can hardly register them, and double-tracked vocals (ala George Martin's Beatles recordings) sound embarrassing when you hear them so close up. Finally, I haven't tried OTA on digital yet, nor on loudspeakers. Dekay's digital design (DDD) is on the agenda though.

Since the preceding post was written, difficulties with this set-up have emerged due to subtle accumulations of RFI on the tone arm cables. To its credit, PhonoCube has enough sensitivity to render this RFI in the wire more audible than any other phono stage I have heard. Also, I am certain that the turntable itself is acting as an antenna and passing on certain amounts of RFI/EMI to nearby PhonoCube. Simply put, at the heart of the matter is that this "minimal signal length TT/PhonoStage hook-up" involves the danger that high-frequency energy can be passed fairly directly into the phono stage. I advise caution, esp. for people who live in areas of high RFI/EMI.
Two things were done: 1.) light-weight, flexible foil shields were installed on the tonearm wire, and 2.) an RFI housing/trap was built to surround PhonoCube. However, night-time listening must be conducted in dim light until I cover the shields and traps with nonreflective material: a 125 Watt shined at the TT system from across the room is enough to cause discharges.
The results of installing OTA digital cables (straight, with no knots or uneven lengths) was positive. I do not know if it is the correct impedance, but with its fast transient response, OTA Stratos wire is perfectly fitted to transmit the bandwidth of digital audio data (which, unlike analog audio, occurs in the Megaherz range).
Surprisingly, the performance of these OTA digital cables deteriorated quite alot with shields. Unshielded, they were clear, detailed, precise, focused, pure. Shielding obliterated their purity. They became awkward, wanting in precision and emphasis. Unshielded, I took a pleasure in digital OTA comparable to the one I get from the bloom given off by well-designed tube amplifiers. Shielding made it grey, warm, blurry. I do not know the precise reasons, but make the effort to construct shields and you will see for yourself.

But I don't think it's advisable use the OTA from cartridge to Phonocube. The problem is the bare OTA wire itself is too stiff to be a good tonearm wire. The sitffness will play havoc with the tonearm's antiskating. This is rather unfortunate because as the output of the cartridge is very low, the fewer solder joints you have the better it would sound. So it looks like in my system I've no choice but to use a more flexible tonearm wire before joining it to the OTA cable.