valve amplifiers and high efficiency speakers

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07/02/2017 02:44 AM
In Pursuit of the Art of Tone! Part 1.

This post is not about the vintage-style 22-gauge Gavitt tinned-copper pushback wire from The Art of Tone electric guitar store that I used to build some very musical sounding headshell leads and a USB interconnect from. Rather, it is about the pursuit of a style of musicality for your hifi that lights up your heart & mind [...]

06/24/2017 05:32 PM
An Adventure With DIY High-Performance Phono Cartridge Headshell Leads!

Back when Yazaki-san sent me a set of headshell leads made of vintage Western Electric WE24GA wire to try, it came as a bit of a surprise to me that headshell leads made such a substantial contribution to overall musical & sonic performance. The difference in sound & musicality between the stock & WE24GA headshell [...]

06/05/2017 10:38 PM
Cinaudagraph Dance Music For 20 Tons Of Water
Cinaudagraph was found in the 30's oddly enough by the same family that found the Boy Scouts. The company was wound down in 1939 but reopened some time later with sales in the 40's. Cinaudagraph did it in style go big or go home with single range speakers 24" and 27". They reportedly had a range of 30hz to 16khz -+5db. They didn't believe in crossovers.

06/04/2017 05:55 AM

Cross-section of Swing headshell. Built for delicate swing...

05/27/2017 04:54 AM

This year Silbatone Acoustics brought the Western Electric Mirrophonic M2 system from the mid 1930s. This second generation cinema system is the grandmother of the famous "Voice of the Theater" and most two way horns systems down to the present day.

There are quite few people criticizing Silbatone approach with their Munich High End Audio exhibition. Well, Silbatone efforts are educational. 

There’s no doubt about their extreme enthusiasm for the “archaic” Western Electric Sound Systems and great old vacuum tube designs. They strongly believe and feel that many lessons for today can be learned from studying past technological history and that a lot can be implemented into the contemporary high-end audio designs. On contrary and I'm more then sure, that many of you would agree with me about the pure arrogance of some high-end audio designers. Their attitude reminds recalls acting of people, that are behaving like they were brought to life without the parents. In similar way some audio designer try to float beyond mortal chains of the past. Well...

I do appreciate Silbatone venture and there are many attributes of the Western Electric approach, that are still viable in the 21st century. You don't have to be a rocket scientist to discover them...

05/25/2017 08:03 AM

I'm really far too close to the recent Japanese experience and am not in the mood to put a decent review of what I heard and enjoyed...

I'd say over-dosed by audio?

Maybe... but never of music, of course.

Sure I'll share with you, folks, a true personal (universal?)  belief: technical redundancies and musical bliss not always come hand-in-hand!

Shinzo's system at his superb music-bar in Fukuoka, with BHT amp, Westrex Acoustilens speakers, EMT 930st, Marantz model 1 preamps and Revox G36s was - maybe - the best overall sound.

Kato system in Toyama was another league, so talking about viable music systems... 

Sato-san in Sapporo was so elegant, yet sound-wise, quite "slow", hi-fish/coldsih, uninvolving.

Kyohara's WE16s system in Ukiha? What a system, visually so impressive, unique!


Yoshihara's system and his private pole?

Impressive system, but... sound-wise?

A big lesson: everything sounds, yet music only seldom blossoms.

Stefano Bertoncello 

05/25/2017 03:05 PM

What you don’t know will hurt you.

Jim Rohn wrote that first, I’m saying it second.

That’s what came me to mind as I saw the most immensely overgrown white Lego pieced amplifier I have seen in 9my entire life. Sure, I have heard the best, or almost the best in the world, mostly products which I have written about over and over time and time again, and for a very long time, stopped writing about stereos, high end or not, simply because, when you make something perfect, you destroy it, (German Romantic Period).

Introduction to insanity, part II.

Some of you might find this to be a non-conventional way of a topic heading, but in this case it honestly feels this way.

I had a call from Nikos Kostadimas on a media server we share and he told me to come by his home that same evening to hear something he wanted help on. Nikos is a friend, no doubt, he is a true lover of music, a true lover of automobiles, and enjoys life as most want to, but never have the courage to. He does, and in a way what he did and what you will read about is simply an extension of his own persona into the world we all love and share within music.

I walked into his home, and saw his boring looking speakers, with a white set of something which seemed or only could be an amplifier. I stared at it for about 3 minutes…and the first thing that came to mind was: When they decided to make this amplifier, what in the world where they thinking? Let’s make yet another amp, to compliment the dozens of high-end amps already out there? Why somebody would get into the arduous task, and which company would deploy on making a spaceship of this size to place in someone’s home? I conceded with the thought that depending on the psychosis, dreams or drugs you have taken in your life, everything is possible.

Way too big, I mean seriously, COLOSSAL! Not to mention they probably cost a leg and an arm, two eyes and whatever kidneys you have left.

The Jadis Eurythmie horn speakers and custom heavy-weight 211-tubed Single Ended amplifiers. Music Bliss at mr. Nick Kostadimas of Chameleon Audio home paradise!

The Jadis Eurythmie horn speakers and custom heavy-weight 211-tubed Single Ended amplifiers. Music Bliss at mr. Nick Kostadimas of Chameleon Audio home paradise!

As I know the owner from the Audiophile Club of Athens, and the fact that we live close to each other, I have heard the aforementioned system, more than just a few times, but never with these amps, so I pretty much knew what to expect to hear, more or less from the systems output. I only remind the reader of this fact since it could have been the system in its entirety which made the job so much more easy for me since I only had one change, variable to work with instead of three.

What about the sound?

Who cares? Just the fact that no one can steal them makes them a safe bet in my mind. Not to mention the WOW factor. Seriously! The colour emitted from the bulbs was so attractive and different in hue that I realized, no artist could ever make this colour on canvas, and that means something very serious. If they could make a colour I have never seen, exactly, then they could after all have made an amp which might be different as well. So, If we include the sound, which up to know seems to be a dream come true, well then I have to rob a bank, and soon. Did I break the news too early? Sorry, this wasn’t written to be a story, but my truth.

I honestly do not know what they are called, nor do I know what we are listening to, it’s beautiful, and it must be a recording which is so well done that makes the system sound so much better, not just different to what it did before. I have heard so many times music that sounds good, and when we get to the music and recordings we know, then I see a whole different basket of fruits.

Until now, song three or four, it seems very well balanced, very natural, insanely natural, without distorting the size of the vocals, the instruments or the sound in any way. The depth on these recordings is unequal to anything I have heard recently, and I do mean the past 52 years of my life.

~170 kg. (each amplifier) of Single Ended – Class A magic. [not in production]

The microphone is not only in the face, but in the orifice of the mouth, maybe down to the esophagus of the artist. Despite the 116 +db we were listening at.

One by one.

The organ, sound like….well like an organ, less stretched for volume as they do live though, as I have experienced sometimes.

The harp, Well, that sounded like the deepest harp I have heard in my life, other than a real harp playing next to me, but again, let us refrain from the over enthusiasm, let us be honest and wait for the real recordings. I know very well that a recording can break or make a system. I am sick of such systems, honestly, I despise systems which play well only on 386 recordings or vinyl that is worth dying for.

Next up was the …

Piano, Wholly Jesus Christ the lord. This recording simply makes the full four quarter piano sound, exactly like a four quarter piano. Simply said, as honestly musical, as life can offer. The hammer of each string seemed to be so true that it carries into your memory unlike any other sound which I have heard, it actually stays in my short term memory for longer, and wants to stay forever had the next note not come along. I just heard the pianist go up and down the keys and it didn’t separate the notes as well as it should have, finally something wrong with this amp I thought. Then the pianist went up the scale, but this time pushing harder on the keys, and the entire blasphemous statement of the previous sent, went away, and was exchanged with the exuberance of luxury that only a piano lounge gives way too. I heard a smaller note come out with the higher scales that were being played. Let’s see what we hear as the night goes on, I said to myself. It could all be just good recordings.

Rhythm, musical and beautiful, but I am concerned if it is natural. The very staccato hits on the guitar seem too soft, despite its musicality, I find them too weak, and I am wondering if this amp indeed is now showing its weakness. Is it too sweet for me to call it top notch ultra-high end audio?

There is a hiss in the recording that was played next, and I wonder if it’s from the recording or the back end because of the decibel count being so high? As you can now understand, I was not prepared to call this amplifier a well deserving adjective unless it really was, and I have to hear it play every instrument and genre of music I have at my disposal.

Next up was the saxophone, it sounded like its being played by the Barry White himself (The most seductive man alive in my opinion), it’s so smooth that if a female went up to it, as its player was “who he was”, there is a moment in your mind when you wonder if your girlfriend could get pregnant if she gets close enough to it. Meaning, the seduction was so empowering that it was sincerely hard to register it in my mind.

I am starting not to like this. It makes everything sound musical, and I know for a fact that life is not perfect, so how can music be.

As you can notice, I am not citing music or artists this time around in this write up, I literally am listening to the notes instead, I am trying to inspect each and every note from each and every instrument, including the sitar, large Japanese drums, while a mesmerizing drum is also pounded by a pair of hands was heard next, no idea of who it was or where it was recorded I just felt what was coming my way. The snare and simple drum set was also bewildering, and again the Sitar was spot on, and the drums before my eyes created the feeling that I was about to  start to float in the room. It was crushing me. The SPL and the impact on my soul is tragically intruding my senses and I was not ready for this, I felt it was doing psychotherapy on me without permission.

Since when can a song, or a stereo, open up your mind and body like a surgeon can within a 3 minute period? It was insane.

I took a break, I needed to recollect my entire ego and drink some cold water. Not to mention I was cold up on that flying carpet for so long…

It was time, I took over the title playing, and I wanted to hear it my way. Enough of this high end crap recording, let’s get down and dirty.

Black magic woman was my first pick, at the lowest quality, was demanded to be played by yours truly. I wanted it full volume so that I could hear the guitar scratch and cry like I know it does. Finally I said and was content to blemish this amp other than its size and weight, but as the guitar strings did indeed cry and scratch, I realized wasn’t a scratch, but a “set part” of the cry enveloping the song, as I believe, it was recorded like by the sound master engineer.

The next title comes with the harshness of every omen I have heard, it has uncovered every amp I have tested and I suggest you use it to test your next amp as well.

Statesboro Blues, where the power of the electrical cord is played like nothing I have heard recorded before. (The Allman Brothers Band)

Finally, some awful strings were heard, as meant to be, but even they were musical, without being soft. That is what I hate about this set up, it’s not soft, but it’s musical, analytic, and entertaining, rich and laid back, like very few soundstages in my past. I will punch Nick in the face unless he puts on my next pick of impossible to play and like music.

Banshee, John Abercrombie, with only 79 shazams, was next. Can you imagine that only 79 people in the world wanted to find out what this song was called, and who in the world played it? Because it sincerely doesn’t sound like something I would want to hear, unless I was blessed by poppy plants and I was a flower child. This turned out to be a Greek tragedy turning up to a dramatic piece of musicality. It was hard to swallow.

I then forced the sick owner of this system to put one more song on, as to test this set up. A simple recording. No tricks nor hard to find music, but something off of the net, literally off of YouTube! I couldn’t go lower than that!

Private investigation. You know the title and you know the artists, need I say more? Well think of it at the sound pressure level of a concert, dare I say even more. This was so loud, I honestly was flabbergasted by how loud this system could go, without one iota of a problem with the distortion of any notes.

This title, as heard by many of us while growing up on a myriad of turntables and then on CD, was in my generation the tune of all tunes to hear loud. Here, at this event where I was, sitting in a house, the loud made all the sense in the world. When we were young we wanted loud because we wanted to feel high, now, for some, but not I, need loud due to older age. We draw from the emotions even at lower volumes and that makes us wiser and much more mature listeners I believe.

So if you want to experience, with no one else in the middle writing about it, just go and experience this for yourself. I will leave it up to you. That is my conclusion.

Go listen and put yourself to the test. The amplifier will do the rest.

By Tony Pothitos

05/21/2017 09:53 AM
Electro-Voice EV 209-8A - 8" Full-range

During a visit to Sakuma's Direct Heating website, I encountered a cool SE 801 amp schematic designed for either a Lowther PM6 or an Electro-Voice 209-8A. I googled the EV 209-8A and nothing came up in Audio/DIY centric English language websites. But there were a lot of US dealers stocking the driver from as low as $18 each.

basic specs

After downloading and studying the detailed specifications at the EV website, I chose the cheapest internet seller and phoned-in an order for a pair. 

It cost $40/pair from Full Compass delivered within a couple of days to my doorstep. In spite of their great customer service, their packing left a lot to be desired - see the slightly wrinkled whizzer in the above right picture - the drivers were free floating in the box, not even tied down face to face ;( 

Due to lack of resources to build the recommended 1.8 cubic foot sealed cabinet, I loaded the EV 209-8A in a Heathkit 1.2 cubic foot ported cabinet, which used to house a Jensen P8RL + RP103. 

Heathkit 1.2cf + EV209-8A

Sharp fall off below ~ 90hz, otherwise the in-room RTA result was satisfactory. The tonal balance reminded me of a good mini-monitor speaker with no upper midrange nasties. It was also quite extended in the high frequency and at no time did I crave for a super tweeter.

Further internet research yielded this Japanese website which did an in-depth study of the EV 209-8A. Based on Chrome browser translation, transmission line loading was used to get around the bass deficiency.

Regardless of Qts values ;) and in keeping with JE Labs tradition, a trial in an open baffle is de rigueur. Since my original pair of OBs are currently in storage, I improvised a 55" wide x 32" high flat baffle using a 24" x 24" x 1/2' thick pine plywood baffle from my experiments in the 90s as the core, supplemented by cardboard extension wings.

OB + EV209-8A

Despite the even sharper fall off in mid bass response as shown in the RTA, subjectively, the bass extension was similar to the EV209-8a/Heathkit box combo. But the scale of the sound field produced by the EV209-8A/OB combo was a lot larger than when it was loaded in the Heathkit cabinet.

Since I discovered that my very first high efficiency speaker (a green KS 14703/Altec 755C) was carefully stashed in a box in the basement, I installed it in the OB to take a trip down memory lane. 

OB + Altec 755C

I've covered the Altec 755C in the Sound Practices No. 17 Homebrewer feature many moons ago, so I will spare adjectives to describe the subjective performance of the KS14703/755C. Suffice to say that the above RTA graph shows it all. It is just in a different class sonically and affordability! Perhaps not a very fair comparison for the EV209-8A because this driver with an intact cone and voice coil is worth about 20 times more when they come up for sale.

So even if I couldn't coax Altec 755C performance from the EV209-8A, its street price, efficiency, relatively flat impedance curve and midrange to upper frequency performance quality impressed me enough to bring it to the attention of the Audio/DIY world. 

05/21/2017 02:52 PM
M.O.C. 2017 - what I missed...

... in my humble opinion, what I missed at last M.O.C. 2017 audio fair is...

Heco Direkt


No MagicoWEVivaMarkLevinsonNagraetc.?


IMHO, these speakers represent the new age of audio, where industry understands - at last - what music lovers look for: real music for real gears and ears, no hyped technical redundancy!

A new product respectfully hinting to classic vintage Saba, Grundig, Telefunken bicone wide-band speakers we all love.

I wish them to sell tons of these nice, no frills speakers... correctly priced at EUR 2,000.00/pair.

Audio made for cool people, not idiotphiles!

05/01/2017 11:59 AM
Preamplifier with nice tennis ball tubes..

Had to convert the R101 preamp due to some residual hum which I could not get rid of without changing the transformer topology.. No worries though, plenty of possibilities here. So rebuilt it using some nice tennis ball shaped Psvane 6SN7's. Kinda neat use of a 6AL5 double diode per channel as cathode bias for the 6SN7 whilst operating in SRPP with a line-output transformer. Bandwith from 8hz up to 210Khz.. And no R or C in the signal path, except from the coupling capacitor..
6SN7 and 6AL5 preamplifier
6SN7 and 6AL5 preamplifier
6SN7 6AL5 preamp

05/18/2017 10:52 PM
Variable Electronic Crossover And Biamplifier
This a really cool article from the always knowledge rich Audio. This issue from 1959.

05/13/2017 09:41 AM
Which is better? The Duelund DCA16GA, DCA20GA, or the Silver/Silk Interconnects?

Which is better? The Duelund DCA16GA, Duelund DCA20GA, or the Duelund Silver/Silk interconnects? The conclusion that I’ve come to is that they all are better, depending upon the application I’m using them for. For example, I had been using a set of nude Duelund DCA16GA interconnects to connect my vintage McIntosh MX110Z tuner-preamplifier and vintage McIntosh [...]