Analog Corner #310: Haniwa HCTR-CO Mk.II phono cartridge, SW1X LPU I phono preamplifier

Hi-Fi in the age of COVID-19
Almost exactly a year ago to the day that I'm writing this—March 11, 2020—the WHO officially declared COVID-19 to be a pandemic. If you weren't paying attention, maybe you didn't see it coming (incredibly, some still deny the pandemic's existence), but I had already canceled a March 14, 2020, flight to Atlanta to speak to the local audiophile society. I'd made the plans for that visit at the Florida Audio Expo a few weeks earlier. Remember hi-fi shows?

No one in our industry knew what would happen as the world shut down, but within weeks, pretty much everyone was thinking, "I'm glad I'm not in the restaurant business"—everyone, that is, who was not in the restaurant business. Or the travel industry. Or ... .

I did manage to get over to Stuttgart in mid-February, to visit turntable and tonearm manufacturer Acoustic Signature, but after that, I became a shut-in.

So did almost everyone else, and within weeks of the shutdown my inbox began filling up with system-upgrade questions. I always get a few emails from readers hoping for personalized advice. I try to answer questions by narrowing down choices while never telling anyone precisely what to buy. Why bother when there are Facebook "experts" happy to do that (usually advising people to buy what they themselves own)?

Such questions were nothing new, but the volume of requests was noticeably higher—and it grew. The dollar amounts people were willing to spend also noticeably increased. Readers wanted to make serious upgrades: new, more expensive turntables, cartridges, or loudspeakers. (I even got a few requests for CD player and DAC advice.)

At first, the action seemed at odds with the job-loss horror stories seen on TV, but soon I began to realize what was happening. People under quarantine needed entertainment, and they were relying more than ever on music played back through their home audio systems: modern hearths on steroids. The ones with money, who could work from home, were ready to spend money, often a great deal of it.

I have always found listening to music on a good audio rig, preferably in a blackened room, superior escapism to watching a superhero movie, or any movie for that matter. That proved even more true during a lockdown, when screen images of maskless people partying in small groups or gathering in large crowds—you notice those images more—provide grim reminders of what we'd lost. When the lights are out, your mind is free to roam to the most abstract places, guided there by your choice of music. A good audio system always does that, but during the COVID lockdown, the experience intensified—at least that's what I found.

The week after I returned from Stuttgart, Von Schweikert Audio's Leif Swanson arrived to set up the Ultra 55 loudspeakers. COVID-19 had not yet been proclaimed a pandemic, but the virus was spreading rapidly, and people were already dying. When I asked Swanson how business was, he said it was really good, especially in Asia.

That was my first inkling that our business was not only not suffering due to the pandemic but was instead prospering. By the time the speakers were picked up, weeks later, Swanson said business was gangbusters. Orders were rolling in from countries like the Philippines, where enthusiasts were special-ordering speakers larger than the largest Von Schweikert catalog speaker—and that one weighs 850lb.

Since then, everyone I've spoken with has similar stories. MSB's Vince Galbo told me that construction of the company's new factory was put on hold as the pandemic overwhelmed the world, but business kept growing and construction is back on. Rega's Phil Freeman told me that since the pandemic began, the turntable business was up 40%, and it had been on an upward trajectory before that. Pro-Ject's Czech Republic factory, I was told, is booked with turntable orders through August.

A New Orleans–area audio dealer I know told me he'd waited months for a dozen or so Audio-Technica LP-120XUSB turntables ($279). When they arrived, he figured he'd better order more right away. As I mentioned in last month's Analog Corner, the distributor told him that A-T is backordered 17,700 120XUSBs. At online audio retailer Crutchfield, all seven A-T turntables are out of stock, with back-in-stock dates ranging from late March to late July; the latter date is for the $799 AT-LP7. Many Pro-Ject turntables are out of stock, too.

This is not a result of COVID-related factory closures, although that did choke the pipeline for a while. These are crazy turntable times.


Record-pressing plants are stressed, too. QRP's Chad Kassem told me he could press just Beatles and Doors and keep the presses fully occupied, but he's got to keep up with other orders. The Verve/Acoustic Sounds series has been a huge success. The first pressing of the John Coltrane Quartet's Ballads sold out quickly; only now, months later, has Kassem found time to press more.

I can't reveal exact numbers, but the first Acoustic Sounds pressing of that record—the one that sold out quickly—was bigger than the total sales of the 1963 release on Impulse!.

Over at Blue Note, "Tone Poet" Joe Harley asked me to guess how many records the label sold last year. I gave him my irrationally exuberant number. It's more than twice that, he said.

It's not all good. This demand explosion has produced some serious quality-control issues. I received more complaints about warpage on Thelonious Monk Palo Alto (Impulse B0032181-01) than on any record I can recall. Clearly this was not the result of a few boxes left out on the loading dock in the sun but rather, I'm guessing, of speeding up the pressing process and not allowing those records sufficient cooling time.

A Different Angle
Phono cartridge manufacturers tell me that demand for their product rose noticeably during the lockdown. Prices for the top models from some brands now exceed $10,000. High prices, we're finding, are no guarantee of good construction quality. Quality control is an especially big problem for companies that buy premanufactured stylus/cantilever assemblies.

The few companies that make those assemblies are just as stressed as record companies about producing more. One result: stylus rake angle (SRA). I've seen a few out-of-spec samples even on expensive cartridges. With SRA, it's possible to measure with even a modestly priced USB microscope and to completely compensate.


A stylus mounted not quite straight on its cantilever. Credit: WAM Engineering.

An equally if not more troubling construction issue has recently surfaced thanks to pioneering work done by WAM Engineering's J.R. Boisclair, maker of WallyTools. Using a powerful, expensive Leica stereo microscope, Boisclair has examined dozens of cantilever/stylus assemblies and found zenith angle errors of 4° or more. (His findings were confirmed by a Leica microscopy expert.) It's more common than you might think, and on some very costly cartridges. Zenith error—the rotation of the stylus relative to the record groove—doesn't matter at all with a spherical tip, but with the more sophisticated profiles found on higher-end cartridges, apparently it matters.

Using the cantilever to set zenith angle (which is how we all do it) is about as unreliable as putting the arm parallel to the record surface is for setting SRA. The interaction among SRA, azimuth, and zenith angle adds to a setup mess. When the zenith angle is off, the stylus reads one side of the groove ahead of the other, and the problem gets worse as the stylus approaches the record center (footnote 1). As if there weren't already enough close-to-the-label problems!

We can't all buy costly microscopes and learn how to use them (especially after tapping out our bank accounts buying $10,000+ cartridges), but Boisclair says he's working on a solution to the zenith-angle problem—although the best solution, of course, is better quality control. Watch this space.

The SW1X Audio Design LPU I MM phono preamplifier
Lotus Group's Joe Cohen contacted me about reviewing this handmade-in-England, vacuum tube–based moving magnet phono preamplifier. Joe is a relatively calm fellow, but he was quite excited about this piece, so I said I'd give it a listen. I'm glad I did.

According to the company's website (footnote 2), Dr. Slawa Roschkow is SW1X's founder, managing director, and chief audio engineer. ("SW" refers to the first and last letters of his name.) His PhD is in economics, and like so many in this field, his journey to the audio business began as a young hobbyist (though he says that in school he was always good in physics, chemistry, and biology). Based on what I read on the website, Dr. Roschkow is still involved in the financial/investment world, so one can hopefully assume this is a well-funded, economically sound hobbyist/idealist company. I like that combination.


On the website, Roschkow says he was drawn to Kondo, Audio Note, and other classic tube designs and that his creations, including the LPU I phono stage, are inspired by them. SW1X products—there's also a DAC, a transport, and a preamp—come in five levels (I–V) and four models (Standard, Special, Balanced, and Signature). All differ in parts and materials quality, output-stage topology, power-supply circuitry, and the "degree of harmonic matching." Not all versions are available for every component type.

The chief differentiating factor between Standard, Special, and Balanced is the "in" and "out" anode configuration of the signal output tube. "In the case of standard you have a resistor going in and a capacitor going out," Cohen wrote in an email. "In the case of the Special, you have a choke going in and a capacitor going out. By far the most transparent ... is Balanced, which has transformer coupling in and out." (Despite the appellation, it is not a balanced design in the more familiar sense.) The phono preamp doesn't come in a Signature version.

The standard version uses one EF86 pentode tube per channel for the input stage and one 6N6P dual-triode for the output stage running in a pure class-A. There's no negative feedback, and RIAA EQ is passive RC (resistive loading/capacitive decoupling). 6X5 tube rectification is standard. Gain ranges from 40–46dB depending upon tube choice. Input impedance is the standard 47k ohms, while output impedance is under 1k ohms.


The basic version sells for a very reasonable (in my world at least) $3150. Options include Audio Note copper foil, Mylar-in-oil interstage and output-decoupling caps, and Audio Note 2W copper, nonmagnetic, tantalum-film resistors on the output tube plates.

The standard version can be ordered with either American-made 5687/E182CC, Soviet-era ('60s) 6N6P, or premium vintage NOS black plate Tung Sol 5687/182CC. You can also get directly heated 5Y3/GZ34 rectifier tubes in place of 6X5s.

The Special version features 5Y3 rectification, Audio Note copper-foil-in-oil caps, M6 EI grain-oriented–core power transformers, and a choke-filtered power supply, for $4295.

To further complicate matters, the version I was sent for review is the Special version but without the 5687 dual-triode, which lowers the price to $4195. I'm not sure why Dr. Roschkow chose a "just short of Special" unit to send for review, but whatever! Maybe he figures I like things a bit edgy rather than supersmooth?


I began with the Miyajima Labs 0.3mV Infinity mono cartridge running into the Ypsilon MC-16 step-up transformer (SUT). One of the great things about vinyl (vs digital) is that you can more easily tailor the sound to a particular era. I know many audiophiles who have "old school" tube phono preamps for mono playback and solid state ones for more modern stereo-era playback (although only a handful of those tube-based phono preamps offer equalization curves appropriate to those older mono records).

The pairs of rear-panel RCA jacks are relatively close together, so I was barely able to fit in the oversized TARA Labs Evolution Zero RCA plugs, but I managed to shoehorn them in. I quickly reverted to the MC-10 SUT because of the LPU I's generous 46dB of gain. The preamp wasn't overloaded; it was just loud.

Footnote 1: Doing the numbers, I find that one side leads the other by only a few microseconds—not enough, in my view, to explain the problem in terms of just phase error. But I do believe that something is going on.—Editor

Footnote 2: SW1X Audio Design, Clartes Ltd., 10 Feering Rd., Coggeshall, Essex CO6 1RN, United Kingdom. Tel: +44 (0)13 7656 2402. Web: SW1X is distributed in the US by Joseph Cohen, the Lotus Group Tel: (415) 897-8884. Web:, and by Jorge Sadurni, Sadurni Acoustics. Tel: (512) 400-8632. Web:


Ortofan's picture

... presently available from Guitar Center, Musician's Friend and Upscale Audio, to name three sources.
How many would you like?
Or, when might you be reviewing it?