je2a3 amp

Twenty three years ago, I built my first 2A3 amp in the basement of the very same house I'm staying in right now. This was a pair of PP2A3 amps with a Mullard-Style driver circuit pumping 8W per channel of pure Class A to drive 82dB/1W/1M (in)efficient BBC LS3/5As, with external preamplification.

As I enter another phase in life, I am back in the same house, mellower with age but hopefully wiser, building a single channel, single-ended 2A3 amp with 3.5W output to drive a 99dB/1M/1W efficient Altec 2-way horn system, with a phono and line stage on board.

This project started with a chassis and choke (amongst other things) handed over by Joe Roberts at the Capital Audio Fest last July. Additional parts were either donated by my hamfest/radio show buddy, Chong Ong or ordered online, like the Hammond 272X power transformer, which came from Steve at Angela Instruments. Back in the 90s, I could have built this amp (except for the output transformer) using parts sourced from hamfests and radio shows. But times have changed, sadly for this project, the only parts I got from a hamfest were the tube sockets ;(

I had been exchanging emails with J-Rob regarding the WE/Altec 32, Emilar horns/drivers, ROK idler TTs, viscous damped tonearms, vintage cartridges like GE RPX, Shure M3D, etc. Among the tubes he suggested I try in lieu of my favorite octal 6SL/SN7s and 5-pin 27/37 and 56/76s, which are getting quite expensive, are the Loktal equivalents + the "Mickey Mouse" plate and grid-capped 2C22/7193 med-mu triode.

WARNING: the 2C22 is not for the faint-hearted, there is over 200VDC in the plate cap if accidentally disconnected while the amp is operating!!!

As depicted in the above block diagram, this is classic (nothing new = boring) JE Labs ;) I used 2 x 7B6 loktals in the RCA derived RIAA phono stage sans variable EQ. A stereo > mono mixer via a WE111C repeat coil to process digital sources was integrated into the chassis, then a single medium-mu triode 2C22/7193 acts as a line stage preamp cap coupled to a Radiotron SE2A3 amp.

!!!WARNING!!! 

The voltages found in this circuit can be lethal, build at your own risk!!!

The chassis was painted in Silver Hammerite, but wiring had to wait due to actual music making and more important projects ;)

Fancy-schmanzy boutique parts were not used in this amp - just plain old carbon resistors, paper in oil caps and electrolytics in the tube rectified/choke filtered power supply.

The amp section is currently fitted with a Noguchi PMF-15WS OPT I got in Akihabara. It sounds really good! You just have to take my word for it since I don't have a scope and audio generator to prove it ;)

At a later date I might swap in the PMF-10Ws, but ultimately I'd like to permanently install an American made OPT, maybe an Edcor or ask/beg Mike L. at Magnequest to wind a single TFA204 OPT just to keep the amp an ALL American classic ;)

Time Out

ala  Turk

Raleigh Twenty

If there were such a thing as a classic folding bike, it'd have to be the Raleigh Twenty, sold from the late 60s until the early 80s. The late Sheldon Brown was very fond of this machine. 

Although it was available in the USA, these are a lot easier to find in their home country, the UK, and its other former colonies like Australia, New Zealand, South Africa and Canada.

Super Cycle Twenty

Fortunately for me, my brother who lived in Toronto patiently scoured Kijiji classifieds and found me this Canadian version - Super Cycle Twenty. He liked it enough that he bought himself the rarer 451 wheeled version.

My all-original Super Cycle Twenty with 406 wheels after assembly, which is in such good condition that only a culture vandal would dare do modifications to it.

Rollei 35 + Tessar 40mm f3.5
Fuji Neopan 400 in BTTB

Sadly, I had to leave these two British classics behind ;(

Restomod Project

I miss the Super Cycle Twenty so when the opportunity came to rescue

 a Raleigh Twenty that had been exposed to harsh elements, it became the perfect candidate for my minimalist, Mini-Velo-inspired R20.



While taking the bike apart, I had to use a hacksaw to remove the rust frozen chain, chain guard, amongst other things that were once attached with a nut or bolt ;(

The steel rims were also suffering the ravages of oxidation. Two weeks of soaking the Sturmey-Archer AW 3-speed hub in WD-40 and it still wouldn't budge. I finally decided it was best to build a new set of wheels and revisit the AW hub at a later date.

My next challenge was dismantling the headset/fork. Somehow the top nylon bushing fused with the stem, fork and headset assembly. While I was playing at the Shippensburg Music Festival, I discovered a local bicycle shop, the owner of which succeeded in taking them apart, as well as a stubborn cotter pin in the crank set. Thanks Terry!

Eventually, I got the frame stripped and prepared for repainting.

Parts for a new wheel set: Sun CR-18 406 36H rims, SRAM Automatix 2-speed coaster brake rear hub,  Sovos alloy front hub with a 5/16" axle, DT Swiss 185mm double-butted spokes + brass nipples

After heeding advice from the nice folks at The Raleigh Twenty forum, I used the Pro Wheel Builder to calculate for spoke length and settled on one spoke length for both front and rear wheels. The front wheel ended up laced in a 2-cross pattern while the rear is a standard 3-cross. 

The frame and fork were painted using 2 cans of Rustoleum black hammerite and left to dry for a week. After cleaning the bottom bracket assembly (cups and axle), it turned out to be in excellent condition. I just repacked the bottom bracket with Phil Wood grease using brand new 1/4" ball bearings. Using a wire brush attachment to an electric drill, the 44T chainwheel and cranks polished up nicely, then I fitted a pair of lighter folding pedals. 

A Ritchey Logic headset replaced the original nylon bushing.

The Origin 8 Classique Sport leather saddle + alloy seat post is significantly lighter than the original Brooks touring saddle with coil springs and its matching steel post. Kenda 20 x 1.75 road tires with new inner tubes were fitted to the rims.

Cork Grips + H2O bottle

Commissioned on Aug. 30, 2016 using the stock 44T chainring + 19T cog supplied by SRAM yielding a low 43.3 and high 58.9 gear inches. As reported in this blog, the SRAM Automatix tends to up shift too early. I haven't done the recommended hack to address this issue but bookmarked it for future reference. Meanwhile, I've learned that modulating pedal pressure prevents shifting too soon, while a slight backpedal or merely coasting can re-engage low gear. I was more concerned with the rather low gear ratios so after almost 50 kilometers of riding, I replaced the 19T with a 16T cog for a longer effective stride of 51.4 and 70 gear inches, respectively.

Looking forward to fun-filled cycling moments on this bike ;)

70s Vintage Folding Bikes - Picnik and Rapido

I love bicycles BUT I don't like bike racks...

...so at the beginning of the summer I started scouting Craigslist for folding bikes. We finally got a deal on four vintage folding bikes in various conditions of disrepair from a bike shop in Pottstown, PA. 

Three of them, disassembled, fit in the trunk. But the nicest of the bunch, the Italian Picnik, deserved a spot in the rear seat.

The Raleigh Twenty was in the worst condition, a long-term project that will be discussed in a future entry.

Picnik - aka Amica or Graziella

This single speed coaster brake Italian beauty just needed cleaning, lubrication and a new set of tires and inner tubes to get back on the road. I thought about flipping this around for a quick profit but da boss loved it and decided to keep it as a collectible ;)

Rapido from Czechoslovakia

The green unit is a single speed coaster brake model while the gold frame is equipped with an early Shimano 333 3-speed internal gear hub. Unusual for 1970s bicycles, both have alloy rims!

With minimum fettling, I was able to recommission the green Rapido using its original white sidewall tires and Brooks saddle from the Rusty Raleigh 20 project, as my daily ride. 

The gold frame was rusty so I stripped and repainted it in hammertone silver.

The refurbished 3-speed Rapido with new Kenda tires and inner tubes and a genuine leather saddle from China for the touring comfort of da boss ;)

On our regular exercise/expedition route ;)

'95 Nissan Altima

Our daily driver "Jill" (nickname inspired by the memory of my parents' first car, "Jack" a hybrid '41/'47 Chevy)...

...is a low mileage 90s surivor inherited from my cousin in NYC.

It survived the 240 mile trek but this rusty bit needed the attention of a body shop to pass MD state inspection. Soon after getting it titled and registered, the water pump and one of the electric fans seized, taking away the radiator. 

DIY

...so there's more budget left for folding bike parts, film, tubes, resistors, capacitors, etc. (toys) ;)

Got a brand new radiator and water pump locally, an original electric fan from the junkyard, wrenches and tools from Harbor Freight to get it back on the road, with help from my apprentice ;)

Chambersburg, PA
Canon 7s + Canon 35/2
Agfa APX100 in Rodinal

The car has taken us to the Baltimore/Washington, DC area, PA, NJ and back to NYC!

Octal EAR 834P phono preamp

During my visit to NYC earlier this summer, my buddy Ding loaned me his home-brewed octal version of the EAR 834P phono preamp using 3 x 6SL7 octal tubes. Powering the preamp is a General Radio 1201-B tube regulated power supply.

Ding is not into boutique parts. Instead, he used carbon film resistors, mylar coupling capacitors and electrolytic caps gathered from Hamfests and surplus stores. Proper grounding and parts placement ensured a very quiet phono stage.

Traditional tube phono stages like the classic Dyna PAS 3 and Marantz 7 employed active RIAA EQ networks inserted in the negative feedback loop from the final stage to the input stage. In the 834P, Tim de Paravicini used active RIAA EQ with a clever twist - the EQ network is fed from the cathode follower output back to the second stage only. IMO, the benefits of this topology are: a 1st stage unimpeded by negative feedback, low noise and low output impedance.

I've been enjoying this phono stage so much that I'm inspired to build my own version. Good job, Ding!

Shippensburg Music Festival 2016

From 1999-2008, I spent three weeks of July making music with these wonderful musicians at the Luhrs Center. It was great to be back!

Vidcaps of rehearsals 

1st week

R. Strauss - Metamorphosen

2nd week

Schubert Symphony No. 9 - Finale

3rd week

Verdi - La Traviata