Friday, September 16, 2022

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.πŸ˜†

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!




Saturday, September 3, 2022

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...πŸ˜”    


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 500Shure M3D + 7DSC35C, 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


Pioneer PL6U + Shure M44
Preamp = JEL Loctal


Pioneer PL6U + Denon DL103
MC step up = Altec 4722
Phono preamp = Shure M65
Line stage = JEL Loctal
Amp = SE71A


Collectors of 45 rpm vinyl, take note!πŸ˜ŠπŸ‘


It can also be the heart of a mono hi-fi set up!πŸ‘πŸ˜Š

Pioneer PL6U + GE VRII mono cartridge
Amp = JEL SE2A3

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



Monday, August 1, 2022

OJAS @ Lisson Gallery NYC

Our dear friends Charito and Joey, whom we haven't seen for over five years, were in NYC visiting for a couple of days. On short notice, Tish was able to take a day off so we were able to meet up with them. Joey is an avid audio DIYer and was a frequent collaborator especially during the annual November Hifi Show when I was still based in Manila. He represents G.I.P. Laboratory in the Philippines. 


It was also timely that Devon (OJAS) Turnbull's HiFi Dream Listening Room No. 1 exhibit at the Lisson Gallery NYC was on its penultimate week. So Joey and I agreed that this was going to be our meeting place! 


The OJAS loudspeaker system utilizes Great Plains Audio drivers, which are currently produced using original Altec tooling - GPA 416B 16" woofers + GPA 288H 1.4" compression drivers. The latter compression drivers are coupled to bespoke OJAS 1505 horns, which are remastered versions of the classic Altec 1505B multi-cells, while Pioneer PTR9 ribbon super tweeters fill-in the top-end octave harmonic overtones. At the center is a Fostex FW800HS super woofer. Devon starts with Werner Jagusch crossovers but driver loading and alignment are all developed in-house and then fine tuned by ear!

Having spent almost a decade studying at The Juilliard School twenty years before the Diller Scofido + Renfro reboot, I developed an immediate affinity for the brutalist vibe of the speakers!


The OJAS gestalt brought back cherished memories of the late Don Garber's Fi audio gallery from the early 90s, which was along 30 Watts Street in SoHo NYC. I wasn't able to ask Devon if he got the chance to meet Don. I bet they would have gotten along really well!


A pair of Altec/Peerless 4722 SUTs are mounted directly on a FET-based phono preamp using vacuum tubes as constant current sources. This was designed by jazz guitarist Steve Berger, who's also the man behind Aprilsound NYC. The adjacent chassis with two large knobs houses a transformer volume control wound by Dave Slagle of Intact Audio.


Being a devoted Garrard 301 listener for many years, Devon is cognizant of the finite supply of these idler driven classics. So for this project, he chose the platter + motor from a Technics SL1200G and mounted them in a custom layered plywood plinth. To assure absolute speed stability and smoothness in operation, a 3-speed linear power supply was specially designed by Linear Tube Audio. Having done DJ work during his younger years, he admits that his choice was partially in reverence to the marque.

Mounted at the back is an Ortofon RMA309 tonearm + a restored vintage SPU-A for stereo LPs and a Dynavector DV505 tonearm + SPU mono CG 65 Di for 78 rpm shellac discs.


Devon's pair of SE300B mono-blocks (fitted with Tango XE20S output transformers) is an homage - not a slavish copy but his own interpretation - to Herb Reichert's Flesh and Blood amplifier published in Sound Practices Issue 8. 


Unlike a typical hi-fi show swarming with silver-haired or balding guys, it was refreshing to be surrounded by a twenty-to-forty something crowd. Devon is attracting and developing a niche market uncharted by mainstream high-end audio publications such as Stereophile and The Absolute Sound. Due to his background in design and interaction with the upper echelons of the fashion and music industries, the whole Sound Practices ethos of music reproduction spearheaded in the early 1990s by Joe Roberts will hopefully reach a larger audience. 


Joey and I spent a couple of hours listening to Blue Note jazz, contemporary classical music, and talking shop with Devon. He was a very gracious host, who candidly gave credit to his collaborators as well as to those people who've influenced and inspired him.

Me, Devon, and Joey

Bravo, Devon, very well done! 
After several years of PMs, it was great to finally meet you. I look forward to more shop talk when you visit my man cave.


Devon's HiFi Dream Listening Room No. 1 exhibit at the Lisson Gallery in Chelsea NYC is really worth hearing and seeing! 

Open Monday - Friday from 11am - 6pm until August 5, 2022.


This 'zine contains comprehensive information about the whole hifi installation + more! 
The poster + 'zine is available at Printed Matter Inc.








 

Saturday, July 23, 2022

Factory Records Shop Dover NJ

Every time Tish and I go on a long drive, I'm always on the lookout for antique malls, flea markets and record stores along the way. On this particular weekend, we were en route to visit friends in Rye, NY. 
 

To avoid the monotony of New Jersey turnpike and congestion on George Washington Bridge, I took the longer route through scenic back roads of PA via New Hope to catch Route 202 and I-287. Then I exited for a brief detour to Dover NJ to check out Factory Records.


Rows and rows of Rock, Pop, Metal, Jazz, etc. of new and used LPs! Some CDs, DVDs and VHS tapes as well.


I'm a sucker for the warehouse vibe!


What use are LPs without record players...


...amplifiers and speakers?


It was a pleasant stop over!


I picked up these three 80s LPs for a very reasonable amount!


Stop by if you're in the area!


The following two pictures were taken by my navigator and co-pilot. 😊


Back on I-287


Crossing the Hudson River via Tappan Zee aka Gov. Mario M. Cuomo Bridge






Saturday, July 9, 2022

SRPP SE2A3 Circuit Redux

Back in the late 90s, I dismissed the hi-mu/low-gm SRPP input/driver because I found that the circuit had a tendency to sound tiring over extended listening. However, my memorable encounter with the Morikawa SE2A3 amp owned by my buddy Jose was haunting. I had to revisit this circuit just to make sure I left no stones unturned. 

Earlier this year, Steve of Angela Instruments shipped me the "shop mule" SRPP SE2A3 amp for a check up. After replacing the leaky coupling caps, the amp was as good as when I delivered it to the shop over two decades ago.  

My hotter operating point = slightly more power compared to Prof. Morikawa's SRPP 2A3 amp.

!!!WARNING!!! 

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

Click here if you'd like to try the SRPP 45 triode circuit.

Use a Hammond 302AX power transformer instead of T1 + T2 A&B


Click here to see the "cleaner" 10kHz square wave from the Morikawa SE2A3 amp

In spite of the 10 kHz square wave spike from the budget Hammond 125ESE output transformers, it was a very refreshing musical reunion with the Angela SRPP 2A3 amp. 

During its residency in the man cave, the amp powered my back up Altec 2-way system above, Altec 755As and Altec 755Cs in Silbatone cabs below. It was totally devoid of the listener fatigue I previously ascribed to the circuit. Even with the brightest and harshest software and/or hardware thrown into the listening chain, I couldn't induce the unpleasant quality which bothered me in the past. 

Then it dawned on me that I started doubting the SRPP's musical abilities when my Altec 2-way project commenced. Sorry SRPP, it wasn't your fault...😟


YMMV!πŸ˜‰






Friday, June 17, 2022

Hub City Vinyl

We took a long drive to visit relatives in Western Maryland for Memorial Day weekend.

I made sure we checked out Hub City Vinyl in downtown Hagerstown, MD. This really cool record store is housed in an Art Deco structure that served as a car dealership in its previous life.


I was based here from the latter part of the 90s till the late 2000s and never imagined a well-stocked record store of this size could thrive in this town.


Notice da boss patiently waiting in the listening lounge?


The Zu Omen speakers driven by Schiit Audio electronics with Steely Dan's "Gaucho" spinning on a Technics turntable made the atmosphere even more endearing!


Towards the back of the building is another room full of LPs and CDs.


The left hand corner of that room had stacks of classic hifi gear!


 This Gates CB1200 3-speed idler driven turntable + Gray 206 viscous damped tonearm definitely caught my eye. But I've run out of space and need to unload to pacify the boss.πŸ˜‰ 

So I hope a blog reader will buy the above set up and enjoy it!🍻


I like the black out aesthetics of this 70s Plainview NY era Harman Kardon 330C receiver, which sported technically innovative circuitry. The rack mountable Tandberg tuner is also interesting!


How about a custom tube amp using 6BL7 tubes?


One of the sales associates told me that the back end of the building will eventually be transformed into a live music venue as the pandemic winds down. This is really great news for the cultural life of Washington County!


If you're a record collector and/or audio buff driving through the junction of I-81 and I-70, this place is a must-see!

Welcome, summer! Safe travels!