One of the fun aspects of reviewing gear from small start-up companies is getting to know the owner/proprietor, who is also usually the designer and builder of the piece of gear I’m reviewing. Such is the case with Mike McGary, something of a new kid on the block in the world of vacuum tube amplifier design. Mike is the owner, designer, builder, and chief bottle washer at upstart McGary Audio, which is based in Gainesville, Virginia, not quite a two-hour drive from my home in south-central Pennsylvania. Mike provided me with a review sample of his very first commercial amplifier design, the McGary Audio SA-1, which is a full-on, big-iron, push-pull vacuum tube amp putting out a robust and conservative 30 watts per channel into eight ohms.
A couple of things stood out as soon as I hefted the box into my listening area and dutifully looked over the manual. First off, this amp is heavy and obviously overbuilt. Next, I noted that it comes with a transferrable lifetime warranty (excluding tubes, of course). When was the last time you saw that come with a piece of audio gear? Even solid state company Bryston, with its famed 20-year warranty, can’t hold a candle to this deal. Better yet, as soon as I let Mike McGary know I had the amp, his first advice to me was to “push it hard.” These observations together told me something about Mike and his commitment to building solidly robust high-end gear with seriously understated specifications. I wanted to know more, so I reached out and asked.
Tell me a story
What I received in return from Mike was a telling and personal story of his journey and adventures in high-end audio, starting (like most of us…) from his early childhood. Some of Mike’s earliest audio memories involve being transfixed by his dad’s home-built Eico tube amp, wondering how those glowing bottles rendered such lovely music. It wasn’t long before boyish curiosity got the better of him, and during his investigations of the secret workings of the “light bulb music box” Mike somehow brought wall power to the amp’s output, permanently frying it in a large cloud of smoke. Dad was not pleased with these early scientific results, and the dead amp was relegated to a box in the garage.
Time passed, and Mike’s interest in home music reproduction only continued to grow. By age 12 or 13, through endless working, scrimping and saving, he was able to piece together a decent high-end system comprised of a good Technics receiver and ADS speakers, costing him a grand total of $700 in the late 1970s. McGary reported to me that he still owns this system today, fully operational and in pristine condition.
Given Mike’s early interest in things electronic, it’s no surprise that he trained to become an electrical engineer, just like his father. His internship took him into a civilian government post with the Army and later the Navy, specializing in weapons systems design and acquisition. Mike’s interest in high-end audio never waned, and his audio systems just got better and better over time. Eventually, he became involved in amateur audio circuit design, thus putting his engineering training and experience to yet another use. Years of tinkering have led to the development of today’s McGary Audio, whose inaugural product is the SA-1 amplifier I have here for review. I’m told that Mike has a few years yet to work at his military-related job, whereupon he plans to “retire” and dedicate himself to his new company.
Oh, and his dad’s fried Eico? Well, once Mike got hot and heavy into vacuum tube audio design, he fetched that old amp from the family garage and repaired it for Dad, returning it to the paternal audio system good as new! As they say, all’s well that ends well, and in Mike’s Dad’s words, “what goes around comes around.”
Back to the McGary Audio SA-1
The SA-1 is an impressive piece any way you look at it. Prior to receiving it, I originally thought its asking price of nearly $4000 seemed a bit steep, but upon really examining it, hefting it, and most importantly, using it, I stand corrected. Mike McGary pointed out to me that his goal in designing the SA-1 was to produce an amplifier that “gives the audio consumer value, not overpriced hype,” and to this end, I think he has succeeded grandly.
When I asked Mike why he chose to design around tubes instead of transistors, he mentioned that it all went back to that old Eico amplifier. Even though he loved the sound of his big Technics receiver, he remained mesmerized by the memory of how musically involving that old amp of his childhood sounded.
When he finally fixed and fired up that antique, he recognized how different it sounded from what he was used to and was forever transformed. From that point on, it was tubes, and only tubes, and Mike decided that he was going to build the best possible amp employing this elderly technology. He built his first real project around the Russian 6C33C-B tube, an output transformer, and a self-designed auto biasing circuit.
Mike related to me how good this design sounded; still tube-like in voice, but much cleaner and clearer than the old Eico. Even though work and other hobbies intervened, he never forgot what he originally set out to do, and the culmination of years of dreaming and hard work is the SA-1 that’s playing away as I write.
So then, a few technical particulars seem in order. The McGary Audio SA-1 provides a very conservative 30 watts per channel at both of its four and eight-ohm taps with total harmonic distortion values of 0.25 % and 2.5 % respectively. Its signal to noise ratio is a respectable 85 dB or better, and it utilizes 9 dB of overall negative feedback. It’s also non-inverting in phase and weighs in at a hefty 46 lbs.
Supplied with the amp are a pair each of 6BQ7A input tubes, 6SN7GTB driver tubes, and two pairs of KT77 output tubes. A reasonable number of alternative tubes are on the “approved list” for those who wish to do some rolling without voiding the warranty. Further, the output tubes are self-biased, so tube matching is not required.
Mike also reports that the very hefty input and output transformers are custom built here in the USA, while all wiring is point-to-point using special silver-coated copper wire terminated with Cardas silver solder. Mike McGary hand-builds each unit with care in his own workshop, so we can safely assume that the amp itself is truly “made in America.”
Looks and Feels
Once I got the McGary Audio SA-1 un-boxed and in place, I could really appreciate how well put together it is. It’s a beautiful thing to behold, and not only in the dark! The heavy and well-constructed steel chassis is powder coated in an elegant semi-gloss mint-green finish that sort of puts me in mind of those really pricy Shindo amps from Japan that I often read about.
The chassis top is an attractive satin black, and the transformers are an eye-catching black gloss. Someone really thought out the appearance of this amp, as the colors work together quite nicely in a traditional tube-amp sort of way. Of course, Mike was quick to remind me that he can do any finish a customer requests at a slight up-charge, but I can’t imagine someone not liking the stock version. The only thing I found a bit odd about the overall appearance of the unit was the back-lit scripted McGary Audio logo on the front panel. If I had my druthers, I’d have gone for something like a brass plate with the same logo, which I find more in keeping with the old-school look I think Mike is going for here. At any rate, Mike’s choice of logo would not be a deal breaker for me by any stretch of the imagination.
One other oddity that a potential buyer should be aware of is that the amp has its inputs on the front panel between the power switch and company logo. Some folks might find such placement awkward and unsightly, and a longer length of interconnect may be required to “make the turn” between preamplifier and amp. This placement is by design, as Mike claims that it greatly enhances performance by minimizing distortion. His reasoning seems sound to me: it’s best to isolate small signals up-front and away from the transformers so that their inherent noise won’t pollute these signals before they can be amplified. Hey, we’re all audiophiles here, so function should always trump form, right?
The SA-1 takes just less than a minute to fully power up, as signified by a soft hum of short duration that tells me it’s time to listen. Mike McGary suggests letting the amp warm up for about 45 minutes before doing any serious listening, but I normally got right down to it.
I ran the SA-1 in for a few weeks prior to doing any serious listening in my second system, driving a pair of Fritz Speakers Carbon 7 SE monitors. In this configuration, the McGary amp reminded me of a lot of other good push-pull ultra-linear designs I’d heard in the past. Present was that lovely lit-from-within, bountifully dimensioned midrange coupled with a warm, but seemingly slightly rolled off treble. The sound was most definitely quite nice (in a traditional tube-like sense…) but not terribly remarkable.
Did the amp need more running-in, or did I just add insult to injury by coupling it with an overly romantic sounding speaker? I wasn’t terribly concerned, as the McGary Audio SA-1 would find itself in the “big rig” for formal evaluation soon enough. Time would tell whether I had just another tube amp or a tiger by the tail…
McGary Audio SA-1 the Big System
The McGary Audio SA-1 was dutifully placed behind a front end consisting of a Sound Devices USBPre2 interface serving as a usb to S/PDIF converter feeding bits to a Bricasti M1 DAC dropping analog goodness to my Linear Tube Audio MicroZOTL 2.0 preamp (review here). The SA-1, armed with signal from the MicroZOTL pre was put to task driving my big ATC SCM 100 passive monitor speakers. I had no idea what to expect, as I had never tried driving the ATC speakers with tubes before. Most folks who opt for this brand of speaker use powerful solid state amps, though I get away with using sand-based amplification with power output as low as 18 watts per channel (see my review of the First Watt SIT-3). As expected, such low powered amps can’t go terribly loud in this system, nor do they fully control the imposing 12-inch ATC woofers. I figured I’d get nice midrange response from the speakers with the McGary amp running the show, but everything else, from bass extension to macrodynamic response was going to be a crap-shoot. What could 30 watts per channel, even if they were Mike McGary watts, really accomplish here?
Alright, so allow me some typical blowhard audiophile largesse here… My initial impression of the SA-1/ATC combo caused me shock enough that I was not only gobsmacked, but I also had to pick my jaw up off the floor not once, but twice! Well, not really, but the combo sounded just huge, as in way bigger than it had any right to be. Bass was deep, with gobs of impact; dynamics were abundant; the system just taunted me to turn up the volume. The SCM 100s like to play loud, but only with the right amplification. With smaller amps, I enjoy the ATC speakers playing late-night, low volume jazz and girl ‘n’ guitar type tunes, and this sort of performance was what I was expecting from the SA-1. Now I see what Mike meant when he challenged me to “push the amp hard.” I’m glad I did.
Tuned for tunes
One indication that the McGary Audio SA-1 was really lighting up the ATC SCM 100s was the music I found myself wanting to hear. Like I said, with the smaller amps, I stuck with smaller scale musical selections; for example, I was listening to a lot of ECM jazz (not a bad thing…). I’d noted, however, that I hadn’t been terribly interested in hearing large-scale symphonic works, which had always been a favorite genre, and this made me a bit sad.
From the very first notes, I could tell that I was home again, and it’s a great place to be! The SA-1 was pumping out real flesh-and-bones orchestral music at realistic concert volumes, and all without any sense of stress or strain. Yeah, I was somewhat taken aback, as this sort of performance with these demanding speakers was not exactly what I was expecting. I’d got a wild hair up my backside, and with a smile on my face, I just kept on cranking up the volume…. And cranking it some more. That McGary amp just kept on putting out, satisfying whatever needs those mean, demanding old British studio monitors asked of it. Very impressive indeed.
Gone altogether was that slightly too warm, overly bloomy, tubey sound I was hearing from the Fritz speakers during the break-in period. The midrange through the McGary Audio SA-1 took on a clean, highly dimensional, yet a subtly tactile character that preserved just the right level of tube-like warmth, but without ever becoming excessive in syrupy sweetness. This amp really plays well with a highly linear, not overly romantic pair of speakers. The SA-1 also seemed just right in its treble presentation into the very special (and neutral) proprietary ATC tweeters. The extension was excellent, with no trace of peaky or unpleasant artifacts. I’d say quite sweet, in fact, but without the kind of roll-off we might expect in more traditional vacuum tube designs.
Oh, but the bass. Let me tell you about the bass. Clear, extended, and powerful it was; just right for giving big orchestral stuff like a Shostakovich symphony the bedrock foundation it needed to soar to the heights it was meant to reach. The bass drum thwacks had the kind of impact in the 11th Symphony that will jolt a dozing listener bolt upright in the chair while testing the glue joints in the speakers. I don’t normally play at volumes to wake the dead, but that bass drum sure could get my attention with the SA-1 at the helm. I normally don’t think of such tight, extended bass as the strong suit of a tube amp, much less one rated at only 30 watts per channel, but I often forgot, while focusing on the lowest registers, that I was even listening to a valved amp! So it was also when I focused my attention onto the low strings of the orchestra; their sonorous buzz lent heavily to that “foundation” I mentioned before that when lacking, makes big orchestral music lose much of its gestalt.
Looking back over the notes Mike McGary sent to me, it all started to make sense. He writes, “I never forgot that tubes sound different from transistor design amps, and even different tubes and tube designs sound different. Most who have listened to the SA-1 amplifier note that it has a tube quality, but also a cleaner, almost transistor sound. It is not a euphoric, tubey sounding amp.” My own listening experience suggests that I more or less agree with Mike here: I feel that the SA-1 has just enough of a “tubey” midrange and slightly sweet treble to let me know that the thing has tubes in it, but the bass seems more reminiscent of a really good solid state design.
Other Musical Genres
Alright, so the McGary Audio SA-1 has got me back to digging my classical/orchestral collection, but how did it perform when playing back some of my other favorite genres, such as stadium rock and soft jazz?
If one were to think of a tube amp as always sounding on the soft, warm, and woolly side, that’s not what’s going on here. Yes, the palpable, lifelike sense of three-dimensionality is all there, but the amp never suggests vapid slowness or lugubriousness. It’s snappy, on-point, and exciting. Listening to Towner, the spot-on timing of the reproduced notes was facilitating my connection with what he seemed to be trying to convey musically, and that’s what it’s all about. I feel that what I am hearing is the character (or lack thereof…) of the SA-1 thanks to the big ATC speakers’ intentional linearity and accuracy. These are top-tier studio monitors, after all.
To be honest, I don’t pay much attention to the spatial properties of gear when listening through my ATCs, as these speakers really focus on the accuracy of tone, dynamics, and pace. They are big and British in that sense. They don’t disappear like good mini-monitors, nor would I expect them to, even in cahoots with a great tube amp like the SA-1. That said, the soundstage is nice and wide, stereophonic images are precise, and there is a fine sense of soundstage depth. These characteristics are as good as I’ve heard with these speakers.
A Quick Comparison
I had to satisfy myself that SA-1 is all I claim it to be. As a last-ditch move, I decided to pull out the big gun… I mean the Howitzer… the $10,000 Pass Labs X250.8 stereo amplifier. I bought the ATC speakers specifically to mate with this amplifier, and boy do they sing well together. If you really want to hear the bass impact and dynamic range these ATCs are capable of, you owe it to yourself to hear them with a monster like the Pass X250.8.
As expected, the Pass amp plumbed deeper into the bass while exercising more ease down low than the McGary Audio SA-1. It also just sounded cleaner overall. However, The SA-1, at less than half the price, pluckily offered up that special midrange presence and inner luminescence that even the best solid-state gear just doesn’t quite achieve. It’s a tube thing, as Mike McGary will tell you. There’s a sense of musical enjoyment with the SA-1 that kept me wanting to listen for hours on end. And if that’s not good enough for you, those bass drum thwacks in the Shostakovich 11th weren’t far behind what the Pass X250.8 was giving me in terms of slam and impact, and that’s saying something.
I think I’m always going to think of the 30 watt per channel SA-1 driving the big ATCs as the “little amp that could.”
And Now, the Night Cap
I have owned (and still own…) small, single-ended triode amplifiers. These are quite special in their own right, but I sometimes forget how satisfying a more powerful tube amp operating in an ultralinear push-pull configuration can sound. And among these types of amps that I have experienced, the McGary Audio SA-1 is right up there with the best. For instance, it reminds me sonically of the Audio Research VT-80 stereo amplifier that I reviewed back in 2017. That amp costs twice as much as the SA-1, and Mike McGary offers a lifetime warranty.
McGary Audio seems to be whipping up some exceptionally built, superb sounding amplifiers. And the value is most definitely there: under what other circumstances would an upstart like Mike (or any other sane individual) beg me to drive his product to its limits while still providing a lifetime warranty? I don’t know if Mike would be happy to hear this or not, but I somehow don’t think I ever got the SA-1 anywhere near its real limits of performance.
So there it is… Anyone in the market for a top-tier, hand-built push-pull vacuum tube amplifier would do well to add McGary audio to his or her list of contenders. I know I would.
Congratulations, Mike McGary and McGary Audio!
McGary Audio SA-1 Stereo Amplifier: $3985US
McGary Audio: https://www.mcgaryaudio.com
McGary Audio SA-1 Specifications
- 30 Watts Per Channel (RMS) Low Distortion, 40 Watts Per Channel (RMS) Waveform Clipping (8 Ohm Load)
- 20Hz – 20kHz bandwidth
- Signal-to-noise ratio: greater than 85 dB unweighted/unfiltered & referenced to full rated output power at 1kHz
- 4, 8, and 16-ohm output taps utilizing gold-plated binding posts
- Gold plated RCA input connectors
- American made 13-Gauge steel enclosure…powder coated throughout (mint green metallic base with satin black top plate)
- Ceramic tube sockets (attached directly to the chassis)
- Point-to-point hand wired with 18-gauge Teflon insulated silver plated copper wire and using Cardas silver solder for all electrical connections with star grounding employed
- Detachable IEC Pangea power cord provided, or optional custom manufactured McGary Audio reference power cord using Wattgate connectors and 12 gauge Teflon insulated silver plated copper wire (please inquire)
- Tube complement: (2) NOS General Electric input (6BQ7A) and (2) driver (6SN7GTB) vacuum tubes, (4) new Russian KT77 matched Gold Lion output vacuum tubes
- Self-bias output tubes require no bias adjustments and configured for Ultralinear operation
- Dimensions: D= 13”, W= 17” and H= 8.5”
- Weight; 46 lbs
- Power: 120V-60 Hz/240V-50Hz (electrically configurable, please inquire if purchasing product for use outside the USA)
- Electrical Engineer Designed and Handmade in Gainesville Virginia with a (transferable) Lifetime Warranty (excluding the vacuum tubes which come with a 90-day warranty from date of purchase)