Tisbury Audio Challenge Amp 1 Solid-State Headphone Amplifier
Tisbury Audio Challenge Amp 1
Continuing on my recent path of reviewing some headphone amps that are NOT as expensive as my first new car was (keep in mind that was in the 1980's), I accepted an invitation from the chaps at Tisbury Audio to review their "Challenge Amp 1", which retails for 350 British Pounds, or approximately $600 US Dollars at the time of this writing.
The CA-1 is a handsome looking, compact headphone amp, with a real wood base and attractive silver chassis. It uses a wall wart power supply, which generally speaking I detest, but this isn't a mega-kilobuck amp, I get it, and it did allow for them to send me the "US Version", meaning one that works on 120V as opposed to the absurd 240V they use in the UK. There are VERY nice looking heavy duty gold plated and chassis mounted (YAY!) RCA input jacks on the back, plus the power switch. On the front there is a high/low gain switch, a 1/4" headphone jack, and the volume control (which impressively is an Alps Blue Velvet). That's it. It's a one-input, single ended HP output design.
It is a reasonable powerful design, however, for low to medium impedance headphones. It was certainly more than up to the task of driving my Audio Technica W-3000ANV's, which are low impedance and high sensitivity. More importantly though, the CA-1 was also up to the task of driving my Audeze LCD-3's, as it outputs more than 1W into 50 ohms. It has the lowest power delivery at very high impedance, but certainly enough for very high sensitivity headphones like most Sennheiser or Beyerdynamic high impedance cans. Something like the AKG K-240 which is high impedance and not high sensitivity might not be a good choice, and the CA-1 isn't up to the task of driving the HiFiMan HE-6, but aside from that, it should do the trick for just about any home headphone one is likely to have around.
I listened to a wide variety of music on the CA-1, which I fed directly from the analog outputs of my Pioneer N-50 Network Music Player/DAC. I played mostly high-resolution (24/96 or higher) digital audio files. I did also connect it briefly to the tape output of my Pioneer SX-1980 receiver so I could listen to it playing vinyl and reel tape. I split time with my W3000ANV and LCD-3's.
The British Sound
I own British speakers. I love British speakers. My main speakers are B&W Nautilus 800's, and I LOVE them. What do I love about them? They sound very, very natural over the long haul, but they don't immediately hit you over the head with this or that. They are not flashy, but they provide superb musical satisfaction over the long haul. Nothing sticks out, and that's what provides the naturalness of the sound.
I have to think that the Tisbury fellows also like this sort of British sound, because that's EXACTLY what I got from the CA-1. Nothing stuck out, but the music flowed in an remarkably natural way, and one that I would not have expected from a $600 solid state amp. When "Lawyers Guns and Money" by Warren Zevon popped up, I thought to myself "this will be a great test for the CA-1", since while I adore the album it's from, "Excitable Boy", it's not what I would call an audiophile-grade recording. But via the CA-1, I was immediately impressed how clean and smooth the sound was, and I was easily able to enjoy listening to the song without any feeling of unwanted edginess. The CA-1 was also remarkably transparent, and so I was drawn deep into the music, which is of course exactly what we all want to have happen! There was no audible grain or veil that I could detect, which further enhances the natural presentation that the CA-1 delivers.
The soundstage rendering was excellent overall. Image specificity was very good, as was soundstage width. The CA-1 would allow music to float outside the headphones, which contributes to a very natural listening experience. Soundstage depth was not world class, but nonetheless good enough to create a nice sense of space. Alison Krauss's "Let Me Touch You For a While" from Alison Krauss and Union Station Live was a very good example of thisthis is a terrific live recording with a very palpable sense of the theater it was recorded inwhen played on good equipment. With the CA-1, I was indeed able to feel that sense of space, which is so critical for a live album. The Challenge Amp was definitely impressive here, and especially for an amp in its price class.
The midrange was very smooth and evenly presented, and in fact perhaps just a bit on the lush/warm side, which again is not really what I would immediately expect from an affordable solid state amp. But there it was. Johnny Hartmann's voice from the incomparable "John Coltrane and Johnny Hartmann" was just achingly beautiful, as was Coltrane's sax, and "They Say It's Wonderful" was exactly that. If a listening system can't evoke an emotional response when playing that song, it has failed. But the CA-1 passed that test with flying colors. I felt bad for poor Johnny! And that's good.
Bass was well defined, articulate, and naturally weighted. It wasn't overweighted, which some people like, nor was it the best super-deep bass I have ever heard. But I didn't ever feel like I was missing anything when listening to music. When I played music I know has super deep bass, I expected a bit more oooomph than I got, but this was only in the very bottom octave or so. Midbass was nice and punchy. If your main thing is organ music, this may not be the best choice. But for the vast majority of the rock and jazz I played, the bass was very satisfying. I personally believe you need a MUCH stiffer power supply than the size and cost of the CA-1 would permit to get better deep bass performance.
And the treble...ahhhh, the treble. SMOOTH, man. Nuanced, delicate, and detailed with no pain. Again, I consider this a neat trick for an affordable solid state headphone amp, and I heard a $3K headphone amp recently that most definitely did NOT accomplish this. Cymbals had the shimmer and presence that they should without the false ringing that they shouldn't. In "Kathy's Waltz", from Dave Brubeck's landmark "Time Out", this was very plainly evident, and really enhanced my enjoyment of that often overlooked gem from that great record.
That said, if you're one of those people who likes to have detail shoved in your face (and that's OK, detail freaks are people too), then this might not be the amp for you. If you like a bit more laid back treble approach, where the high-frequency detail is there but in a way where it doesn't stand out on its own in a way that makes it feel spotlit, then the CA-1 is a good choice.
Putting the Pieces Back Together
Sometimes when I dissect the sound of an amplifier I get done and I feel like I have worked really hard to describe the sound of the amplifier for you, dear reader, but in the process have failed to provide the sum of the parts. Some amps actually don't create the needed overall sense of continuousness to make me feel that waymeaning that the sum of the parts is NOT a greater whole. Those amps don't usually provide lasting musical satisfaction, in my experience. But what I think makes the CA-1 worth writing about, and hopefully also worth reading about, is that it does EXACTLY that. Its whole presentation is well beyond the sum of its parts. The integrated musical presentation that comes out of this little box is on a much higher level than I was expecting, and higher than one typically finds at this price point.
I have a VERY expensive tube amp sitting on my desk waiting to be reviewed next. I haven't turned it on yet, or even plugged it in. Typically I wouldn't have been able to dispense with reviewing a $600 solid state amp fast enough when such a treat as a giant megabuck tube amp was waiting. But so thoroughly have I enjoyed the little Tisbury that I lingered with it. I'm confident that many people who try it will have the same reaction. The Challenge Amp 1 definitely challenged my beliefs about what an amp of its type and cost could do. Highly deserving of being included in InnerFidelity's "Stuff We Like".