6moons audio reviews: Audio Tropic Musical Machine

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Reviewer: Michael Lavorgna
Analog: Rega P3, Denon DL-103 cartridge, Auditorium 23 moving coil step up, Fi Yph phono stage
Digital: Audio Aero Capitole MKII, Red Wine Audio Monica 2 DAC
Tuner: Voice of Music AM/FM Stereo Tuner (1960s vintage)
Preamp: Déjà Vu Audio
Amp: Fi 45 Prototype, Fi X, Fi 421A, Minute
Integrated Amp: AudioTropic Musical Machine [on review]
Speakers: Cain & Cain Abby (Normal), DeVore Fidelity Super 8, The Horn Shoppe Horns (original version), Lamhorn 1.8 with AER MKI drivers [in for review]
Cables: PHY interconnects, Shindo interconnects, Auditorium 23 Speaker Cable, JPS Labs Digital AC Power Cable, Audience PowerChord, ESP Essence Power Cord, and Z-Cable Heavy Thunder V2 on the Blue Circle MR,
Stands: pARTicular Basis Rack
Powerline conditioning: Blue Circle Music Ring MR800
Accessories: Symposium Rollerblocks Series II under AA Capitole, Yamamoto Sound Craft PB-10 Ebony Bases under Abbys and Bailey, PS Audio Ultimate Outlets, and AudioPrism Quiet Lines. Room damping provided by lots of books
Room size: 13' w x 16' d x 9' h
Review component retail: $3,000 as reviewed, $4,000 for the new "i" version

Penny Lane is in my ears and in my eyes
There's a great painting by Andrea Del Sarto in the Metropolitan Museum of Art in NYC, of The Holy family with the infant St. John. What I find particularly fascinating about this painting is Del Sarto's depiction of what can be described as emotionally charged space.

The painted 'distance' between hands conveys more than inches; a creationism three-card Monte. Del Sarto also invites you, the viewer, into the scene as witness. It's intimate. It's sensual.

Our HiFi gear does the same kind of spatial maneuvering of both the represented music and the listener's relative position to it. If you like intimate, if you like your music in your ears and in your eyes, the AudioTropic Musical Machine may be for you.

It's a clean machine
"The Machine is an ongoing (for eleven years) experiment in reducing the number of components, stages, parts, in a purist music reproduction system to the absolute minimum; in making a lean, mean, musical machine - thus its name. The amp circuit is absolutely as simple as technical rigor allows; a singly-driven differential 5965 is the gain/splitter/driver for a pair of triode 6V6 outputs. Source switching and volume control is onboard; no preamp is necessary. The whole rationale here is to have as few devices, components, pieces of wire and solder joints in the signal path as possible."

The Machine is an integrated amp delivered with a quad of new Electro-Harmonix 6V6GT power tubes run in singly-driven push/pull pairs and fully differential on input and output. Driver tubes are a pair of 5965 and power rectification is handled by a 5AR4/GZ34. The Machine puts out 6-8 watts and 0.04mV of hum & noise despite using AC heaters. Yes, that's 40 microvolts. If you were listening to some tunes on your Machine and in-between tracks a mosquito landed on your >100dB speakers, you'd hear it. You'd hear it because it would be louder than any noise coming from your speakers. [For all his linguistic panache here, I doubt Michael knows just how apt his description is. I had the privilege of meeting Poinz over Xmas in Cyprus when he installed a Machine in a massive multi-way horn system with 30' straight bass horns and ALE compression drivers everywhere. This 5-way horn system with Acapella ion tweeter clocks in at an average of 110dB. Poinz was clearly nervous. While he had optimized the circuit for ultra low noise in Hawaii, there was no telling whether his test bench measurements would translate in Cyprus. He needn't have worried. His AudioTropic amp was as quiet as a door nail and proceeded to embarrass many a far more expensive tube amp this gentleman keeps in his wine cellar for back stock and to change the system as it pleases his mood - Ed.]

The Machine uses Silk transformers from SACThailand and high quality parts throughout, including SwitchCraft silver contact switches, ceramic/gold tube sockets, Panasonic TSHA, Nichicon Muse, Mundorf Silver Supreme caps, Riken and Kiwame signal resistors and high purity copper or silver-in-Teflon signal wire. Standing a diminutive 18" W x 8" D x 6" H, the Machine review sample chassis is aluminum and African Mahogany which is absolutely stunning. You'll never get the full effect in a picture. It's like looking at skin. Translucent. Part of the rationale for the tiny chassis width and height is to keep signal paths as short as possible. Not only is Eric Kingsbury -- Mr. AudioTropic and Poindexter on the boards -- concerned with a minimal number of elements but each element is also given just as much space as it needs. No more, no less.

"There's a great deal of discussion and a strong awareness, in DIY audio, of the importance of implementation; as of course there would be. I saw a thread on a forum where the subject was the relative 'percent importance' of circuit design (audio and/or power supply), parts selection and implementation. You know, like 25% design, 25% parts and 50% implementation; the general run of the discussion being the high importance of implementation. Now, my own instincts on this run 100% design, 100% parts, 100% build. If you dig my jive. But any time I come upon a discussion about the overriding importance of implementation, my attention is arrested because two things are happening here for sure. First, these are guys who have built a lot of gear and know what's happening. Second, there are going to be some juicy trix to be picked up; especially if they get a little irritated with each other and start bandying licks. My main instructor in the ECET program described an expert as, "Someone who's screwed up every possible way.""

I encourage everyone reading this to go to the AudioTropic site and read everything, especially the pages in the Projects section. There you'll be told everything you need to know to build your own Musical Machine if the feeling moves you. While I appreciate the DIY route, I will tell you that the implementation of the Musical Machine -- and Mœbius preamp -- are artful. The care and handling is exquisite. When forking out any kind of money for anything, isn't it nice to get something that actually resonates with craft? With the handy work of someone who's obviously into what he's building and you're buying? This may be a machine but it's exudes warmth and the human touch. And that's before plugging it in.

The standard Machine comes with two inputs but you can order yours with up to four. The third input runs $100 and the fourth $50. You'll also notice a pair of RCA outs for those using a self-powered sub. The binding posts on this version (more on the "this and that" version later) are minimalist affairs that will only accommodate spades or bare wire. I used some banana-to-spade adaptors for the review since my speaker cables are fruit-terminated. Our front panel controls include two toggle switches, one for source selection and one for power. If you opt for more inputs, the toggle goes away and is replaced by the same Elma switch used on the volume control. You'll also see two pots sitting next to the 6V6s. These are for adjusting bias. Yes, manually. It takes all of a few minutes and a $15 Rat Shack meter. Once dialed in, I never had to readjust. Since this is an integrated amp, you make your two source connections, attach your speaker wire, power cable and power on. Simple and straightforward. I have a soft spot for integrated amps, for their simplicity. But hadn't found one I wanted to live with. Until I met the Machine.

One brief aside. I found this explanation for warm-up time on the AudioTropic site and it's one of the better explanations I've come across so I thought I'd share. "The amp currently sounds slightly fizzy when first turned on, taking about one album to settle down. This is probably fresh capacitors and should subside in a few dozen hours of operation. My sample still takes about an album to 'focus', though; I hypothesize that maybe vacuum tube gear, which produces substantial heat, has to approach thermal equilibrium to stabilize sonically."

Machine Music
"When I was first planning this circuit out, I was looking at all the ez-drive devices that the front end could modulate; EL84, 6V6, 6Y6, 6BL7 and sort of leaning toward the EL84, since there seemed to be more of them around, and at the time they were the only one being currently produced. Also at that time, I hung sometimes with Mark May, who had a pro and hi-fi gear fixit shop. I would get parts from him and look at old tube gear he and his tech didn't have time to sort out.

"I went in there one day and he was playing the radio through a little guitar amp, to test the repair. Now, this was hardly hi-rez but it sounded so good, it let go of the music so well that hi-fi Mike Lavorgna could sit and listen to it all day and only say stuff like, 'Yah, I always loved this band' or 'You know, this guy really had pipes but he wasn't much of a musician, was he?' I mean, it took you right away from the sound, to the music. I listened to a couple tunes and asked Mark, 'Jeez, man, whatchoo got here? This thing is the berries!' He said '6V6s, Poinz, no way you can make 'em sound bad. Sound even better in triode but not much power; seven, eight watts max. Hey, where ya goin? Don't you want some parts?'

Lucky first guess."


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Reviewer: Michael Lavorgna Analog: Rega P3, Denon DL-103 cartridge, Auditorium 23 moving coil step up, Fi Yph phono stage Digital: Audio Aero Capitole MKII, Red Wine Audio Monica 2 DAC Tuner: Voice of Music AM/FM Stereo Tuner (1960s vintage) Preamp: Déjà Vu Audio Amp: Fi 45 Prototype, Fi X, Fi 421A, Minute Integrated Amp: AudioTropic Musical Machine [on review] Speakers: Cain & Cain Abby (Normal), DeVore Fidelity Super 8, The Horn Shoppe Horns (original version), Lamhorn 1.8 with AER MKI drivers [in for review] Cables: PHY interconnects, Shindo interconnects, Auditorium 23 Speaker Cable, JPS Labs Digital AC Power Cable, Audience PowerChord, ESP Essence Power Cord, and Z-Cable Heavy Thunder V2 on the Blue Circle MR, Stands: pARTicular Basis Rack Powerline conditioning: Blue Circle Music Ring MR800 Accessories: Symposium Rollerblocks Series II under AA Capitole, Yamamoto Sound Craft PB-10 Ebony Bases under Abbys and Bailey, PS Audio Ultimate Outlets, and AudioPrism Quiet Lines. Room damping provided by lots of books Room size: 13' w x 16' d x 9' h Review component retail: $3,000 as reviewed, $4,000 for the new "i" version

Penny Lane is in my ears and in my eyes There's a great painting by Andrea Del Sarto in the Metropolitan Museum of Art in NYC, of The Holy family with the infant St. John. What I find particularly fascinating about this painting is Del Sarto's depiction of what can be described as emotionally charged space. The painted 'distance' between hands conveys more than inches; a creationism three-card Monte. Del Sarto also invites you, the viewer, into the scene as witness. It's intimate. It's sensual. Our HiFi gear does the same kind of spatial maneuvering of both the represented music and the listener's relative position to it. If you like intimate, if you like your music in your ears and in your eyes, the AudioTropic Musical Machine may be for you. It's a clean machine "The Machine is an ongoing (for eleven years) experiment in reducing the number of components, stages, parts, in a purist music reproduction system to the absolute minimum; in making a lean, mean, musical machine - thus its name. The amp circuit is absolutely as simple as technical rigor allows; a singly-driven differential 5965 is the gain/splitter/driver for a pair of triode 6V6 outputs. Source switching and volume control is onboard; no preamp is necessary. The whole rationale here is to have as few devices, components, pieces of wire and solder joints in the signal path as possible."

The Machine is an integrated amp delivered with a quad of new Electro-Harmonix 6V6GT power tubes run in singly-driven push/pull pairs and fully differential on input and output. Driver tubes are a pair of 5965 and power rectification is handled by a 5AR4/GZ34. The Machine puts out 6-8 watts and 0.04mV of hum & noise despite using AC heaters. Yes, that's 40 microvolts. If you were listening to some tunes on your Machine and in-between tracks a mosquito landed on your >100dB speakers, you'd hear it. You'd hear it because it would be louder than any noise coming from your speakers. [For all his linguistic panache here, I doubt Michael knows just how apt his description is. I had the privilege of meeting Poinz over Xmas in Cyprus when he installed a Machine in a massive multi-way horn system with 30' straight bass horns and ALE compression drivers everywhere. This 5-way horn system with Acapella ion tweeter clocks in at an average of 110dB. Poinz was clearly nervous. While he had optimized the circuit for ultra low noise in Hawaii, there was no telling whether his test bench measurements would translate in Cyprus. He needn't have worried. His AudioTropic amp was as quiet as a door nail and proceeded to embarrass many a far more expensive tube amp this gentleman keeps in his wine cellar for back stock and to change the system as it pleases his mood - Ed.]

The Machine uses Silk transformers from SACThailand and high quality parts throughout, including SwitchCraft silver contact switches, ceramic/gold tube sockets, Panasonic TSHA, Nichicon Muse, Mundorf Silver Supreme caps, Riken and Kiwame signal resistors and high purity copper or silver-in-Teflon signal wire. Standing a diminutive 18" W x 8" D x 6" H, the Machine review sample chassis is aluminum and African Mahogany which is absolutely stunning. You'll never get the full effect in a picture. It's like looking at skin. Translucent. Part of the rationale for the tiny chassis width and height is to keep signal paths as short as possible. Not only is Eric Kingsbury -- Mr. AudioTropic and Poindexter on the boards -- concerned with a minimal number of elements but each element is also given just as much space as it needs. No more, no less.

"There's a great deal of discussion and a strong awareness, in DIY audio, of the importance of implementation; as of course there would be. I saw a thread on a forum where the subject was the relative 'percent importance' of circuit design (audio and/or power supply), parts selection and implementation. You know, like 25% design, 25% parts and 50% implementation; the general run of the discussion being the high importance of implementation. Now, my own instincts on this run 100% design, 100% parts, 100% build. If you dig my jive. But any time I come upon a discussion about the overriding importance of implementation, my attention is arrested because two things are happening here for sure. First, these are guys who have built a lot of gear and know what's happening. Second, there are going to be some juicy trix to be picked up; especially if they get a little irritated with each other and start bandying licks. My main instructor in the ECET program described an expert as, "Someone who's screwed up every possible way."" I encourage everyone reading this to go to the AudioTropic site and read everything, especially the pages in the Projects section. There you'll be told everything you need to know to build your own Musical Machine if the feeling moves you. While I appreciate the DIY route, I will tell you that the implementation of the Musical Machine -- and Mœbius preamp -- are artful. The care and handling is exquisite. When forking out any kind of money for anything, isn't it nice to get something that actually resonates with craft? With the handy work of someone who's obviously into what he's building and you're buying? This may be a machine but it's exudes warmth and the human touch. And that's before plugging it in. The standard Machine comes with two inputs but you can order yours with up to four. The third input runs $100 and the fourth $50. You'll also notice a pair of RCA outs for those using a self-powered sub. The binding posts on this version (more on the "this and that" version later) are minimalist affairs that will only accommodate spades or bare wire. I used some banana-to-spade adaptors for the review since my speaker cables are fruit-terminated. Our front panel controls include two toggle switches, one for source selection and one for power. If you opt for more inputs, the toggle goes away and is replaced by the same Elma switch used on the volume control. You'll also see two pots sitting next to the 6V6s. These are for adjusting bias. Yes, manually. It takes all of a few minutes and a $15 Rat Shack meter. Once dialed in, I never had to readjust. Since this is an integrated amp, you make your two source connections, attach your speaker wire, power cable and power on. Simple and straightforward. I have a soft spot for integrated amps, for their simplicity. But hadn't found one I wanted to live with. Until I met the Machine.

One brief aside. I found this explanation for warm-up time on the AudioTropic site and it's one of the better explanations I've come across so I thought I'd share. "The amp currently sounds slightly fizzy when first turned on, taking about one album to settle down. This is probably fresh capacitors and should subside in a few dozen hours of operation. My sample still takes about an album to 'focus', though; I hypothesize that maybe vacuum tube gear, which produces substantial heat, has to approach thermal equilibrium to stabilize sonically." Machine Music "When I was first planning this circuit out, I was looking at all the ez-drive devices that the front end could modulate; EL84, 6V6, 6Y6, 6BL7 and sort of leaning toward the EL84, since there seemed to be more of them around, and at the time they were the only one being currently produced. Also at that time, I hung sometimes with Mark May, who had a pro and hi-fi gear fixit shop. I would get parts from him and look at old tube gear he and his tech didn't have time to sort out. "I went in there one day and he was playing the radio through a little guitar amp, to test the repair. Now, this was hardly hi-rez but it sounded so good, it let go of the music so well that hi-fi Mike Lavorgna could sit and listen to it all day and only say stuff like, 'Yah, I always loved this band' or 'You know, this guy really had pipes but he wasn't much of a musician, was he?' I mean, it took you right away from the sound, to the music. I listened to a couple tunes and asked Mark, 'Jeez, man, whatchoo got here? This thing is the berries!' He said '6V6s, Poinz, no way you can make 'em sound bad. Sound even better in triode but not much power; seven, eight watts max. Hey, where ya goin? Don't you want some parts?' Lucky first guess."

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