Monday, October 1, 2018

Kutztown Radio Show September 21-22, 2018

All pictures were taken with a Fuji X-E1 camera + Canon 28mm f3.5 LTM lens.


I wasn't able to attend as many hamfests/radio shows this past summer. So I made sure I went to Kutztown.  


This speaker caught my attention as something I've encountered in a vintage magazine in the past. Since there was no one manning the booth, I went on...


A pair of University Lowboys + an EV Aristocrat


Nice Gates CB77, but I couldn't afford it 😞


Belt-driven Rek-O-Kut


Scott 299, LT110B FM tuner, Fisher KX100, etc.


Fisher PP EL84 mono block


My bud Larry always has a live demo set-up.


Sonographe SD-1: mid-80s Philips 14-bit oversampling chassis with twin TDA1540 DACs, audio section tweaked by conrad-johnson, nice piece but check out that asking price 😲


Tubes galore!



I scored a TDA1543 equipped Magnavox CD player from this booth. 



Lots of 70s-80s Hi-Fi equipment 



Used CD prices are at an all-time low 😃


The speaker I spotted earlier kept haunting me. I just had to give it a new home. My gut feel was right - it's a Stewart Hegeman-designed omni-directional speaker. 😎









Tuesday, September 11, 2018

Noguchi Transformer Co. Ltd, Closing


Noguchi Transformer Co. Ltd announced that they are closing on September 29, 2018.😞😞😞


Located at the basement of Tokyo Radio Department Store in Akihabara, I was first exposed to their existence in the early 90s through their ads in MJ Audio Technology and Stereo Sound Tube Kingdom magazines. 

MJ 11-1994 

Back in the 90s they ran 2-page ads for Tamura, Tango and their in-house manufactured transformers.

Hashimoto

I was glad to see their store when I visited Tokyo in November 2015. They still had a good stock of Hashimoto, some Tamura and a comprehensive line of their house brand transformers. 

Noguchi + Tamura 
I am speculating that just like everywhere else in the world, the Japanese market for DIY/vacuum tube/single-ended triode amps is also shrinking. This explains why these manufacturers are closing shop, 😞 not to mention the fierce competition from China.

"mid-price" Finemet OPT ad in MJ 12/2015
  
The Noguchi Finemet models represented their finest quality output transformers.


Even if I stretched my budget a bit, it was a good call that I added a pair of PMF-10WS and PMF-15WS + a single Finemet FM3WS-H and a pair of Finemet FM6WS to my collection. ðŸ™‚


Sayonara!


!!UPDATE!!

As posted by "dan" in the comments section below, the entire line of Noguchi is now represented by General Transformer in the same location at Tokyo Radio Department Store in Akihabra. 





Saturday, September 1, 2018

Azzolina Audio KS12024

Western Electric KS12024

Western Electric KS12024
Note: ~ 140° throat bend

The Western Electric KS12024 is a 2-piece cast aluminum 4-cell sectoral high frequency (800-1000Hz cut-off) horn with a 50°H x 40°V dispersion pattern. It was implemented in the Western Electric L-8  and L-9 speaker systems.

Western Electric L-8
from the Silbatone Collection

Western Electric L-8  = 1 x WE754A + 1 x KS12024 + 1 x WE713B (phenolic diaphragm)

Western Electric L-9

Western Electric L-9 = 2 x WE754A + 2 x KS12024 + 2 x WE713B

Western Electric L9
(Note: 2 x WE713B)

Images were taken from J-Rob's KS12024/Western Electric L-8 post at Hifi Haven. If you want to learn more about the Western Electric L-8 and L-9, you can download the pdf file at the bottom of Joe's post.

Read about J-Rob's musings (post #125) about the original KS12024 and Azzolina repro at Hifi Haven.

Late 40s Western Electric Brochure
from www.hifilit.com

The KS12024 horn was from the same era as the WE32A horn that included the venerable WE757A studio monitor, WE713x compression drivers, WE755AWE756A and WE728B direct-radiator speakers.

Having been a long-time user of the Altec 755A, Altec 32A/C and more recently an Altec 756B, I consider this period as the golden age of design and manufacture of permanent magnet transducers. So when J-Rob offered to loan his personal pair of Azzolina Audio 3-D printed KS12024 horns for me to blog about, it was a privilege and opportunity difficult to pass up.

Azzolina Audio KS12024


I've been a frequent visitor to the ElectraVolt blog but never imagined I would be listening to, let alone reviewing, Charles Michlin's KS12024 reproductions. 


The original Western Electric KS12024 has a 0.7" round opening* but this Azzolina remake was optimized for 1" compression drivers like the Altec 802 that I am using for this review. As relayed by J-Rob, Charles claims the oval (rather than round) aperture sounds better. 

*All the WE horns from this era (including the 32A) were designed for use with the WE713x compression drivers and shared the same aperture size


Just like the original, this is also a true 4-cell compound sectoral horn. AFAIK, this is the model built from an amorphous plastic material. Everything else you need to know about the Azzolina KS12024 can be found here.

Testing

Altec 414A/614 + Azzolina KS12024/802 + 3000H

The Azzolina KS12024 horns were tested in the Altec 2-way system. 

Altec 414A in 614 cab 

Altec 414A woofers in 614 bass reflex enclosures running in full range mode

High-pass XO w/HF eq

Altec 802-8D compression drivers (below) with 16 ohm GPA 34852 diaphragms were mounted to the horns using the above high-pass crossover


Amorphous Plastic Azzolina KS12024 vs. Plastic Altec 32C


Altec 32C + Altec 802

This horn presents a back row perspective and may sound too laid back to those who prefer a closer to the stage presentation. The mid-range is juicy, full and vivid without a hint of shout. While the highs are feathery smooth, silky and airy, which I've only heard from its smaller sibling, the Altec 3000H. Tish (my wife) describes this horn as sublime. I think the 90°H x 40°V dispersion helps provide that holographic and lush atmosphere. 

I've written so much about this horn. Just use the search button on the right hand corner to find past entries.


Azzolina KS12024 + Altec 802

I was initially lured into the 3D-like midrange this horn produced and that lingered on. There's an uncanny realism to male and female vocals as well as musical instruments that renders an "in your room" presence. Compared to the 32C, this horn offers a front row perspective. Yet there isn't a trace of harshness or shout. Definitely a horn that will appeal to those who find the 32C too laid back yet need a horn that doesn't sound like a horn.

It is superior to the 32C in terms of articulation and detail without ever sounding analytical. There's a lot of snap, if I may borrow a term from its owner 😉, just like its stable mate - the WE/Altec 755A.

Azzolina KS12024 + Altec 802 + Altec 3000H

Tish thinks it is as good as but not quite as lush as the Altec 32C. I agree. This is primarily a tonal balance issue. Due to the prominent midrange, the extreme treble frequencies are slightly subdued giving a less airy atmosphere. Adding the Altec 3000H to fill in the uppermost octave helped in approximating the lushness of the 32C. But I still found myself wanting more "hall sound." I speculate that the KS12024's narrower 50° horizontal dispersion contributes to the comparatively austere background. Perhaps I am belaboring this point since my personal preference when I attend concerts is to sit towards the back row so I can relish equal amounts of direct and reflected sound.

Summed up

2 x KS12024 = 100° H x 40° V

These two horns share the same sonic DNA but are genetically modified for different applications. The more up-front and involving Azzolina KS12024 betrays its theatre heritage versus the mellower 32C, which was intended for near-field monitoring. I can't help but wonder if a horn design combining the virtues of both designs is a possibility.








Monday, August 27, 2018

Magnavox CDB473 and Philips TDA1541


With barely 400 CDs and just a handful of SACDs and DVD-As in my collection, I didn't invest heavily on silver discs as much as I did on LPs. Likewise, I've spent much less on digital playback hardware.

However, due to the resurgence of interest in vinyl LPs and streaming, used CDs are available all over at bargain prices. Since I'm not committed to burning all my silver discs to a hard drive having had my own share of failures in the past, I was inspired to look into maximizing my CD playback system.


Sony DVP-NS755V

For the past 15 years, I relied mainly on this Sony DVD/SACD/CD player. It showed me that SACDs had an edge over CDs. Yet it proved that neither format was on equal footing with my LP set up. This is a polite sounding machine that also doesn't do anything great. Prior to the Sony, I owned an early bitstream (ca. '93) Philips CD921. It sounded sooo boring, I connected the digital out to an Audio Alchemy Dac IThe Box to spice things up a bit until it (the CD921) prematurely died.

Nevertheless, I was still missing the lively sound of my first CD player, a Magnavox CDB472 I purchased in 1987. I had an inkling that the "bitstream" buzzword of the 90s was not an effort to improve sound quality but a watered down technology/marketing hype for manufacturers to maximize profits. Since I was more interested then (as now) in older technology, I placed digital audio tech aside, focused on learning how to build triode amps and high-efficiency speakers.

Denon DVD-2910

To re-acquaint myself with the few DVD-A titles I have, I acquired this reasonably priced Denon DVD-2910 multi-format compatible relic from the mid-2000s. It weighs almost 10 pounds, is built like a tank, is mechanically and functionally more refined compared to my entry-level Sony above due to higher quality materials (more metal). If this didn't sound better, it can serve as a CD transport for an external DAC. Fortunately SACDs did sound better, but not sure about CDs though...

Time Travel Machine


Philips TDA1541A

Ever since I embarked upon improving my internet streaming set up, I had to refresh and update my knowledge of Digital Audio, PCM, DSD, DACs, etc. It was inevitable that I'd encounter R2-R vs. delta-sigma debates in internet audio forums. I also discovered that there's a sub-culture of CD collectors/music lovers/DIYers (as opposed to meter readers/latest is best audiophiles) who maintain that the most musical sounding CD players are those 80s machines fitted with the more complicated and expensive-to-manufacture 16 bit Philips TDA1541 chip.

Under the hood of a CDB473

Out of retro-tech nostalgia, it was only fitting that I trace my steps back to my first CD player in ca.'87, the Magnavox CDB472, which used this ubiquitous chip. I did a bit better this time around with the higher model CDB473 which is equipped with a co-ax digital out, and can also be used as a CD transport. Considering that this unit celebrated its 30th birthday in December of 2017, it is a glowing testament to Philips' excellence in engineering and manufacturing that it still works today. 

Let's see how the Magnavox's 16 bit DAC chip which was truly designed for Red Book CDs fares against the Delta-Sigma DAC chips found inside the Denon and Sony.

Magnavox CDB473

From the very first CD I fed into the tray, the Magnavox sounded more transparent and dynamic while the Denon and Sony sounded comparatively veiled and compressed. Even my wife heard its superiority. The CDB473 may not possess ultimate refinement but there's an honesty in its musical presentation that draws the listener into the music, just like analog LP does. 

Truth be told, I don't remember the CDB472 sounding this good back in the 80s. But I had a totally different system then and was just beginning to wean myself off of the influence of underground audio journals of the era, which were largely pro-vinyl LP/anti-digital CD. I guess hindsight is indeed 20/20 with regards to the Philips TDA1541. I was too young to learn and appreciate its virtues. Besides, a year after this CDB473 was manufactured, Philips introduced bitstream technology, followed in the late 90s by Delta-Sigma, both claiming greater linearity. These were the technologies that dominated the market from the 90s to the present and also the sound I associated with the playback of 16-bit/44.1kHz mastered CDs.