VAS Audio: SPU GME II and Supex SD900 IV retip + Stax UA-3NL and Tokyo Sound ST900 repair

 

VAS Audio Workshop

Before lockdown, Ding promised that he'd introduce me to his friend, Steve Leung, of VAS Audio. He's had his Denon DL103S, Ortofon SL15, Supex SD900, and other classic cartridges re-tipped and repaired by Steve. As the pandemic wound down, I finally got to meet Steve and brought the following MC cartridges for new tips, as well as tonearms for repair at his shop.

Ortofon SPU GME MKII

SPU GME MKII - BEFORE

My Ortofon SPU GME MKII has had a hard life ever since it was gifted to me by my SETUP buddies in the 90s. It's been on semi-retirement since I acquired an SPU#1s + a late 60s or 70s(?) SPU-G (below) with a low mileage nude mounted conical stylus.

SPU-G

This SPU-G portrays a wider and airier sonic landscape with perhaps a bit more detail compared to my more recent SPU#1s. It also sounds more organic than the GME MKII. 

SPU GM(E) MKII - AFTER

I attribute the SPU-G's sonic superiority to the better polished nude mounted conical stylus vs. the bonded conical stylus of the SPU#1s. So I asked Steve to fit his finest nude mounted conical stylus on my GME MKII.  

Ortofon SPU GM(E) MKII

Agreeing to my downgrade idea,😉 Steve may have turned the GME MKII into an SPU-G equivalent of the SPU-A wood. All I know is, it can stand up to my cousin's SPU Synergy!😊

Supex SD900 MKIV

BEFORE

The Koetsu Black and Supex SD900 were my dream cartridges back in the 80s. When I finally found an SD900 I could afford, it sported a ruby cantilever + complex stylus profile upgrade.😏 Although traces of the classic Supex tonality were still there, it sounded compressed and swamped by dry analytical detail.😞

AFTER

I asked Steve to work the same magic on my Supex as he did on Ding's, albeit with a twist. We agreed upon an aluminum cantilever just like the original and I requested for another nude mounted spherical stylus.

SD900 MK IVs (s = spherical)

Steve remarkably transformed the Supex! The harmonic richness and dynamics this classic MC cartridge is known for was restored. To my ears, the SD900's edge over my SPUs and DL103s is its ability to focus and retrieve detail without inducing tinnitus. Because of Steve's phenomenal restomod job, I'm no longer yearning for a Koetsu! 😊

Stax UA-3NL

Being an ardent fan and committed user of the Gray 108 viscous damped tonearm and its Japanese clones for monaural hifi applications, I needed to experience a modern iteration of a uni-pivot. This design actually dates back to the late 60s. Scroll down to page 1413 for the review in the Hi-Fi News November 1969 issue. The UA-70 seems to be essentially the same tonearm updated in the 70s with an anti-skate mechanism.

More Stax info at vinylengine.com

I added the UA-3NL to my collection in early 2018 and paired it with my Thorens TD124 and Sony TTS 2500, respectively. I was going to include this tonearm in my Alfred Bokrand AB309 write-up but one channel dropped out. 

When I finally accessed the internal hair-like strands of enameled wire, I realized that repairing it was beyond my DIY abilities.

Similar to the knife-edge bearing'd SME 3012, the Stax presents a mid to back row concert hall perspective, which is an atmospheric experience without any loss of detail. Although I've used it satisfactorily with the SPU#1S, it brings out the best from cartridges that track in the 1.5 > 2.5 gram range. Just like the SME 3012, the UA-3NL may not appeal to listeners who favor a front row seat/kick drum on your chest presentation.

Thanks to Steve's skill and nimble hands, I'm enjoying my UA-3NL again!

Tokyo Sound ST900

This 9" tonearm from the early 60s has an NHK broadcasting heritage. Comprehensive information about the ST900 is available at audio-heritage.jp. Surprisingly, the spindle to pivot mounting distance wasn't specified. 

So I took out my ancient Cart-Align protractor, did some measurements with my Ortofon SPU#1s cartridge attached and got a pivot to spindle distance of 223mm. I haven't had any problems with cartridges I installed conforming to the SPU's overhang.

Claus Volke and this Japanese audio blog have more to say about this tonearm.

It's equipped with a non-standard 4-pin connector in which the negative phase of the right channel is internally grounded. This limits its use to the stock plastic head shell. In an effort to make it compatible with modern metal head shells, I successfully detached the 4 pin connector at the base of the tonearm pillar. It turns out the ground connection was near the head shell collet, which I couldn't remove. Instead of risking damage, I relied on Steve's expertise.

The design may have been inspired by the Ortofon SMG212 and SKG212 with added Japanese innovations. It is quite massive and can easily balance a 30+ gram SPU. So far the lightest cartridge/head shell combo I used successfully was 19.5 grams. Given its high tolerance bearings, it's an ideal partner to the Denon DL103, Ortofon SPU, and similar low compliance cartridges. Consider this as an excellent alternative to the classic Ortofon AS/RM/SK/SMG 212 series tonearms especially if you prefer the svelte proportions of a compact plinth!

iPhone video clips of the MC cartridges and tonearms in action

"Fire" from The Elements

Joe Henderson + Alice Coltrane

Supex SD900 MKIVs + Stax UA-3NL 

Turntable: Thorens TD124

MC step up: Altec 15095A

Preamp: JE Labs Loctal

Amp: morrison micro 2A3 reimagined

Speakers: Altec 755C in Silbatone cabs

"All Or Nothing At All" 

from 

Freddie Hubbard's Open Sesame

Ortofon SPU GM(E) MKII + Tokyo Sound ST900

Turntable: Thorens TD124

MC step up: Altec 4722

Preamp: JE Labs Loctal

Amp: morrison micro 2A3 reimagined

Speakers: Altec 755C in Silbatone cabs

Steve, the master craftsman, and Ding

Looking forward to Steve's visit to the man cave!🍻

Kutztown Radio Show September 2022

All pictures taken with a Fuji X-E3 camera + Voigtlander Color-Skopar 35mm f2.5 LTM lens

The early bird...

A pair of Bose 901s with tulip stands!

Nice day to be out of the pavilions.

Acoustic Research AR10𝛑s

Radios are the stars of the show!

But audio is catching up.😊

Radio and hifi catalogs, magazines and other literature

Just like vacuum tubes, phone booths were a common sight in the past.

Lots of vintage tube components!

I can empathize with the person behind these reimagined Dynaco preamps since I used to be a Dynakit hacker in the 80s and 90s.😊

Heath W4, Radio Craftsman FM tuner, Dyna ST70, etc.

Hickok tube tester + a pair of MC40s

Sherwood FM tuners, Heathkit W5, Realistic tube amps, etc.

JBL 4311Bs + Rek O Kut B16 with a Shure M236 tonearm

Altec Santana II - not what I consider a classic.😕

I wish DVHRC also has a winter event!

This was how electronics was taught before the computer era.

Western Electric 753C crossover

Classic cameras are regular guests at radio shows and hamfests. However, this is a rare and unusual 35mm rangefinder camera outfit from the 40s - the Kodak Ektra! As the link explains, it was a very sophisticated design for its time but the shutter was very unreliable. Its Contax and Leica contemporaries were much better!  

Realistic 42-2109 phono preamp upgrade

Even if I was a Radio Shack devotee in the early 80s, I didn't pay much attention to this RIAA phono preamp because it didn't have high-end audio pretensions. As the saying goes, ignorance is bliss.😆

scanned from page 36 of the 1989 catalog

This unit was first introduced in the 1980 catalog (p. 22) as part number 42-2101 at $19.95, then as part number 42-2109 for $24.95 in 1989, and made its final appearance for $27.95 on page 103 of the 1992 catalog.

Realistic MKVII idler-driven turntable, a future feature😊

With the resurgence of interest in LP playback, it was rediscovered by aficionados and has developed quite a following. No ICs or op-amps are to be found inside. It's a simple discrete circuit, which minimizes signal processing.

!!!WARNING!!! 

The voltages in this circuit are potentially lethal! Proceed at your own risk!

The circuit is a basic two stage cascade + a negative feedback RIAA EQ looped from the output back to the input. It is very similar in topology to its tube forebears - the Shure M65 and the phono section of the Dyna PAS.

Typically, I don’t subscribe to a wholesale approach of replacing caps but this is a very simple circuit that was built at a certain price point. Since I had some decent quality parts surplus from my CD player and DAC modification projects, I replaced the electrolytic capacitors in the signal path with film type WIMAs and increased the filter capacitance in the power supply section.

In stock form, I was already impressed by this preamp's listenability when passing through my loctal tube line stage. The parts upgrade tidied up the sound further, but it wasn’t a magical transformation.

In terms of midrange presence and transparency, low level detail, micro and macro dynamics, this preamp isn't the equal of the Shure M65 or a refreshed stock Dyna PAS phono section. Its main advantage over its vacuum tube forebears is low output impedance. This could plug into the 10k input Z of the Nobsound NS02g/JLH 1969 with no loss of frequency extremes. I won't recommend that with the M65 or PAS. There's also a slight graininess in the midrange that wasn't ameliorated by parts upgrades. That said, I don't know if one can find a "plug 'n play" phono preamp in the $100 range (or possibly more?), which will provide as much musical pleasure!

Japanese Idler-Driven Turntable Part 1: Pioneer PL6U

Ever since I discovered the Shield MO19 (aka Neat P58H) and Realistic MkVII at the turn of the new millennium, I've become fascinated by, and in the process have collected a few Japanese idler-driven turntables. To my ears, none of them measure up to the Garrard 301, 401 or Thorens TD124. However, the models I'll be covering in this series, IMHO, offer great musical value for money when properly sorted.

For this initial installment, I'm featuring the Pioneer PL6U, which I used as an interim turntable when I returned to the US in 2016. It's the little brother of the Pioneer PL7, which was built to much higher specifications.

With a 100V AC motor fitted, the PL6U was a 3-speed turntable made for the Japanese domestic market. Both 50Hz and 60Hz pulleys are supplied since both AC frequencies are used in Japan, depending on which part of the country you're in. As pictured, the 60Hz pulley is installed since that's the AC frequency in the US. I use a 100W step up/step down transformer to make sure the motor is fed exactly with 100VAC.

The 4-pole AC synchronous motor + switch linkage are on a sub-chassis that's mounted beneath the stamped steel main chassis.

Removing the bottom cover revealed a box. Originally, this box would have contained the tonearm, auxiliary tonearm weight, head shell, an oil vial, 45 rpm adapter, 50 or 60 Hz pulley, stylus pressure gauge and screw driver. I got the turntable with the tonearm mounted sans head shell but the 50Hz pulley + screw driver were inside the box. Sadly, all the other accessories were gone...😔    

The cast aluminum platter is quite hefty at almost 2 lbs. 

It's undersized at 10" (25mm) diameter but it spins on a finely machined 3/8" (10mm) spindle.

The tonearm is a very simple static gimbal type and thus, a tracking force gauge is necessary to set proper VTF. Other cartridges that match well with the relatively massive (albeit also undersized) tonearm include the Pickering V15/Stanton 500, Shure M3D + 7D, SC35C, etc. Practically any magnetic cartridge with a conical stylus that tracks over 2 grams will work well. In fact, the bearings are good enough to even handle a Denon DL103 moving coil! Watch and listen below.

Except for perished motor mounts, the unit is in excellent condition. After fitting a fresh set of rubber motor mounts, a thorough cleaning + lubrication, the unit played beautifully on its original idler wheel!

Let's hear some tunes!

Pioneer PL6U + Shure SC35C

Phono Preamp = Shure M65

Line stage = JEL Loctal

Amp = SE71A

Speakers = Altec 755C in Silbatone cabinets

Pioneer PL6U + Shure M44

Preamp = JEL Loctal

Amp = Radiotron SE2A3

Speakers = Altec 755C in Silbatone cabinets

Pioneer PL6U + Denon DL103

MC step up = Altec 4722

Phono preamp = Shure M65

Line stage = JEL Loctal

Amp = SE71A

Speakers = Altec 755C in Silbatone cabinets

Collectors of 45 rpm vinyl, take note!😊👍

It can also be the heart of a mono hi-fi set up!👍😊

Pioneer PL6U + GE VRII mono cartridge

Mono preamp = JEL Variable EQ phono 

Amp = JEL SE2A3

Speaker = Altec 756B + 32C + 806 + 23744

Despite the solid engineering that went into this record player, it was and still is an entry-level unit. It portrays the musical energy idler-driven turntables are known for, but not quite up to the refined standards of the Realistic MKVII or Shield MO19. That said, the videos show how much fun I had with this unit!

More information about the almost identical Pioneer PL6A can be found at audio-heritage.jp.

Go to Part 2