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.