July 2017

Ampsandsound Agartha Vacuum Tube Stereo Amplifier And Headamp
Master Of Two: Making sweet music for headphones and speakers.
Review By Dave Hanson

  I've always been a big fan of tubes, but I'll admit that my admiration has grown into an all-out obsession since my review of the ZMF Atticus headphone. The Atticus is simply one of the world's most enjoyable headphones with the right tube amp behind it, and after reading about some other listeners' successes in pairing it with California-based Ampsandsound's lovely looking gear, I decided to explore their lineup for myself.

Agartha ($3,600) is quite an interesting amplifier, to say the least.

According to designer Justin Weber, "It's designed to be what someone needs at the stage in life they are at. Situations change, it's nice to have equipment that supports those changes." I'll admit I was a little skeptical. Sure, you'll probably find a decent headphone output on plenty of speaker amps, but it's hardly the same quality as a dedicated flagship headphone amp, right? Would a speaker output on something marketed as a headphone amp fare better? Could it truly be a master of both? Let's find out.

Taking The Stage
To get a feel for the Agartha's performance on speakers, I brought it to the showroom at the local hi-fi shop, Needle Doctor, who generously let me sample it with several pieces of equipment over a couple of days. The Klipsch Heresy 3 is a sensitive speaker with a bit of a hit or miss reputation. With the wrong amp pairing, the midrange can sound somewhat nasally and recessed. This was not so at all when paired with the Agartha. The midrange was creamy, sweet and liquid smooth as I listened to Fiona Apple' s "When the Pawn..." streamed via Tidal. The Agartha gave deep, deep insight into the tone of the individual instruments while still putting Apple's rich and smoky voice clearly in the spotlight. Dynamics here were strong and punchy, giving a good physical rhythmic pulse to the music that had me nodding my head the whole time.

Testing a live recording, I found California Guitar Trio's "Highlights" album once again showcased Agartha's ability to give deep, deep insight into the tone. It projected a nice realistic stage where you could easily envision the performers. Perhaps more impressively, not only could you differentiate between the three guitars through the great separation and image placement, but via their actual unique tone. Very impressive resolution, with top-notch musicality to boot! I asked Weber about his design philosophy and how Agartha was able to give such deep insight into the instruments. "I always had a desire for old school 300B tubes and horns," he replied. "They may not be the dynamic performers they could be with more power, feedback or gain stages on the input. But in doing it the old way, there is a truth to the midrange that these more complex systems don't do as well." I would say I have to agree, between the midrange purity and the excellent staging, there was something very "live" about the music through this setup.

Shifting over to a vinyl setup the next day, we paired Agartha with the Origin Live MK3 turntable (with the silver tone arm upgrade and Hana EH cartridge) and the Croft Micro 25 preamp's phono stage. Listening to side 1 of Coltrane's "A Love Supreme" was even more impressive than the previous day's session. The superior inner resolution and microdynamics where on full display here in Elvin Jones lively drum work, making each ride hit sound remarkably unique. Coltrane's sax was smooth and soothing, with no nasally sourness or midrange shout to be found.

All the while, the terrific soundscape continued to impress. Imaging was super strong, especially the height, which was absolutely exceptional. Sitting in front of a wall of speakers, it was almost impossible to tell which speakers were actually playing. My brain was telling me the sound was coming from the LS50s on the stands, when the sound was actually coming from the Heresy speakers on the floor. Depth and width were also quite good, with each player occupying a very distinct space on the stage in front of me. Overall, it was a stunningly musical and holographic experience.

Riding The Wave Of A Sonic Tsunami
Swapping over to headphones, it is instantly apparent that Agartha is an amp that looks just like it sounds: huge. The dynamics pack a powerful wallop. And as you would expect from a 300B tube amp, the spotlight shines brightly on a larger-than-life midrange with a gorgeous, bloomy, liquid flow. But perhaps the biggest and most impressive thing about Agartha was once again the massive soundscape and sharp imaging. Paired with any of the headphones I tried with it, the stage was large, lively and three dimensional, with great height, width and depth. Everything about it was big, and that made the music all the more epic.

Down low the bass slammed hard with a bit of tubey roundness to the notes. I found the presentation added a special sense of realism to instruments like upright basses and cellos, where the additional tube harmonics better communicated the complexity of the reverberations coming from deep inside the wooden body. Agartha's  bass wasn't quite as punchy or resolving in the bass as my solid-state Wells Milo (reviewed here), but the naturalness with which it was conveyed made Agartha special in its own distinct way.

Similarly, the overall attack and decay were also slightly rounded in a positive, tubey way. The Agartha takes a more natural and laid-back approach, by just letting the music flow. Instead of making you nod your head back and forth to the constant rhythmic patter of machine gun microdynamic impacts, the Agartha's headphone output makes you sway your head side to side in an ever-surging current of musical flow. Liquidity is rarely so well defined by a single piece of gear. Tone was certainly first class with the stock tubes, trailing only a pinch behind some of my favorite amps with their best tube pairings. With an upgrade to a premium tube like the Sophia Royal Princess 300B ($1200), I'm quite certain Agartha has the potential to surpass them with its 300B magic.

Pairing with several different headphones, I found it was able to drive the notoriously difficult 85dB/mW Abyss AB-1266 planar magnetic headphones (reviewed here) pretty well, unleashing the powerful dynamic thrust the headphone is known for. Bass was solid and pretty resolving, though the treble on Agartha was a tad splashier than the aforementioned Milo with the Abyss. That being said it wasn't very far behind, and this could likely be fixed with the right tube. It was a solid match overall, and I know Jeremiah Griffiths of Ampsandsound uses this particular pairing for his personal headphone setup.

Paired with the venerable Sennheiser HD800 and ZMF Atticus, Agartha was definitely able to milk the best out of both headphones. The HD800 was open and expansive, with very well-controlled treble, a filled out midrange and punchy bass – exactly what you hope for with a well-matched amplifier. I would very happily recommend this pairing for pretty much any kind of music. With the Atticus, Agartha was similarly excellent, able to bring out the full midrange magic and dynamic slam I had been looking for, giving the headphone a super engaging and ultra-euphonic presentation. Again, an easy pairing recommendation.

With every headphone I tested, the tone and timbre continued to stand out for their rich naturalness. Even with the stock tubes, strings and vocals were warm and sweet with a breathy sense of air and emotion. Large orchestration was especially impressive given the beautiful tonality and vast sound scape. Instruments had plenty of room to operate in their own space, with excellent layering front to back and side to side. With such strong, detailed inner resolution on each instrument, large ensembles had a very special richness to them that was deeply emotional and downright awe-inspiring.

Sorting Out Some Minor Quibbles
The only real knock on the headphone output is the relatively high amount of background noise. There was a distinct transformer buzz that was quite audible when music wasn't playing. It was easily drowned out by music, but still faintly noticeable if you were really, really zoned-in on it. If you don't need the world's blackest background this should be just fine, and I think the amplifier's many positive traits definitely outweigh this negative, but some people demand absolute silence from their amplifier, and those folks would likely be a bit annoyed by this hum. Another, much more minor complaint is that there isn't a ton of play on the volume pot when listening to headphones. That being said, it isn't all that difficult to get the volume you want and the volume pot is actually perfect for speakers, so it's hard to actually call it a fault. More of an issue to be aware of, if you have a hot source and this happens to be your pet peeve.

And the final issue I feel I should point out is that there is no muting relay for the speaker output when headphones are plugged in. Given the purist's approach to the circuit design, I wouldn't imagine there would be such a piece of tech involved, but still, it would be a nice and convenient touch. Since the Agartha' has excellent performance and versatility in so many far more important areas, I didn't feel like any of these were deal breakers. In practice, they were easy to overlook. That being said, everyone values different things in their audio gear.

Final Thoughts
Overall, I found the Ampsandsound Agartha to be an absolute joy to listen to with both headphones and speakers. I think I can safely say, this is a piece of gear that is truly able to drive both equally well, and in that respect, it's actually a very compelling value at $3,600. In fact, after listening to it with speakers I actually told Justin Weber, "Hey man, you really undersold me on this speaker output!"

Given Agartha's exceptional sound and incredible versatility, I find this amp to be an excellent recommendation to someone who wants to listen to both headphones and speakers at a very, very high level without going to crazy on the budget. Source aside, one could have an Agartha, a set of Heresy 3 speakers, some good cables and a great set of headphones like the HD800 or ZMF Atticus for about $7000. Granted, that's still a good chunk of change, but these days it's hard enough to get to an end game setup for either speakers or personal audio at that price, so being able to kill two birds with one tube amp, could be a tempting idea for many people.

If you're the type of person who likes the idea of an all-in-one solution to get to speaker and headphone hi-fi heaven, definitely give the Ampsandsound Agartha an audition.

Additional Equipment Used in This Review
Sennheiser HD800
Sennheiser HD600
Abyss Headphones AB-1266
ZMF Atticus
HiFiMAN HE400
HiFiMAN HE500
Klipsch Heresy MK3 Speakers
KEF LS50 Speakers
Croft Micro 25 Preamp
Wells Audio Milo Headphone Amplifier
Glenn OTL Headphone Amplifier
DecWare CSP3 Headphone Amplifier
Origin Live MK3 turntable (with the silver tone arm upgrade)
Hana EH Cartridge
Audio-GD DAC-19
iFi iDSD Micro Black Label
Chord Mojo
Audience Ohno Speaker Cables
DanaCable Lazuli Headphone Cables
DanaCable Onyx Interconnects
DanaCable Trustream USB Cable
Wireworld Electra 7 Power Cables
AudioQuest Niagra Power Conditioner
Acoustic Research M2 Hi-Res Player
Tidal Hi-Fi Streaming
Audirvana

Specifications
Type: Vacuum tube stereo amplifier
Headphone Output at 32 Ohm: 1.5 Watt
Noise (Headphone Output): 660uV
Speaker Output at 8 Ohm: 5 Watts
Noise (Speaker Output): 760uV
Size: 15.5" x 11.5" x 8.5" (WxDxH)
Price: $3600

Company Information
Ampsandsound
1 Bel Flora Ct.
Aliso Viejo, CA 92656

Voice: (323) 868-9722
Website: www.AmpsandSound.com