_ (Un)Fortunately Sonny has done a great job already in describing the amplifier and how it sounds. I have to say I can agree with his findings but I will of course give you my point of view on the Tisbury Challenge Amp 1 in a reduced review as well.
Tisbury is a company that focuses on the technical side of things and when looking at the Tisbury website, you can clearly see that in all the technical specs and design details. But not only has the tech stuff make it look good, the design of the Amp 1 is absolutely stunning.
Unlike Sonny’s unit, my amp arrived dent free and I have to say it is one of the nicest looking amplifiers I have had at home in a long time. The wood and aluminum combination is simply stunning to look at and the lay-out of the CA1 is simple but effective. I even have it sitting in the middle of the living room and my girlfriend hasn’t complained once about it not fitting in to the interior. It actually is smaller than you would think measuring only 204mm x 170mm x 74mm. The only issue I have with the CA1 is that it is so light you have to hold the amp down when plugging in or unplugging your headphones, if not the amp will move all over the place. Some extra weight or more slide resistant feet would have been nice in my opinion.
Sonny has more than sufficiently covered the technical part but I do want to highlight a couple of things. For starters the Muting Relay: a muting circuit with turn on delay and fast acting AC detection protects your headphones from any harmful transients during power on/off. If the AC supply is switched off or interrupted, your headphones are disconnected instantly. The front LED displays the status of the protection circuitry: Blue = normal operation. And green = muting circuit active. I think we can all remember the reports of a certain American made amplifier where the amp killed several headphone drivers because of this, so it was nice to see this “security” implemented in their design/
Secondly, the power supply: an off board mains transformer with low noise. Forget about using one of your fancy power cords, this amp comes with its own wall charger. Less fancy is the UK power cord termination, so you will have to use an adapter to be able to plug in your amp. (The adapter is supplied by Tisbury in their defense). I would advise those wanting even more technical data to check out the full specs here.
I have been using the Cypher Labs Theorem and especially the Resonessence Labs Herus as source for the CA1. Headphones used were the Sennheiser HD650, Audeze LCD-2, Hifiman HE-500, NAD Viso HP50, Philips L2, Beyerdynamic DT770.
Before going into detail on these headphone & amp combinations you have to know that the CA1 sound really is like Sonny described it: Bass, present and detailed but doesn’t have the biggest body. Mids are detailed but more forward and a maybe little on thin side (as in body wise). Treble is detailed and nicely extended. Overall a fast, clear, detailed and more forward sounding transparent solid state sound. Sound stage is fairly good and focus is on vocals. Our returning readers know we usually do prefer a warmer, smooth sound with good body and mids but not everyone likes that. If you do like bass, warmth and body however, I’m afraid this amplifier isn’t the one for you. This amp is all about clarity, vocals, air and detail. And that can be really good!
For me personally it makes my beloved Senn HD650 not sound the way I want it to sound: I love the thick sound and bass and I don’t want to clear it up. One thing I don’t really agree with Sonny is that I do find the amp to have a rather big impact on the headphone’s sound. Power wise you don’t need to worry, it will drive as good as anything. But back to the HD650, this combo just isn’t for me but I didn’t expect it to be either given the characteristics of the amp.
The NAD Viso HP50 is a uniquely tuned headphone (review upcoming) with special kind of mids. I can’t say I really liked this combination. I’m having a hard enough time already to love the HP50 and in combination with this amp it just isn’t working for me: especially the body in the bass and mids are missing too much for my ears.
The Philips Fidelio L2 is a great all-rounder and of course doesn’t need a lot of amplification. However the CA1 drives it really nicely; bass and mids have good detail and treble is great. I’m really digging this setup and the L2 scales up nicely. With this headphone there is no issue whatsoever with the more forward sound signature of this amp. Recommended, especially with strong vocally music!
The DT770 AE/32Ohm, which we all love, doesn’t need much amping either but always sounds better when properly amped. This is one of those headphones that can really change depending on the amplifier used. You can make it sound really bassy and warm (like with a Duet) or you can clear it up. And that’s exactly what this amp does; it clears up the DT770 for those who like it. Lovely detail, great mids and bass and perfect treble. A great combination, the best so far.
With the Hifiman HE-500 you have to turn up the volume or use the gain switch. I personally preferred using high gain over more volume and this is something that rarely happens but for some reason this works on the CA1. The result is a clear and detailed sounding HE-500 with great vocals and treble. I’m convinced the majority of HE-500 owners will love the sound out of this CA1. I myself always tend to use the HE-500 with a warm tube amp or with the warmer sounding V200 solid state amp. While I have to admit this combination sounds really good, I love it even more with some more warmth and bass. But I have to be honest and give Tisbury credit for this combo, it sounds sublime.
The Audeze LCD-2 sounds best on low gain and so the volume dial goes right up to 12 o’clock. Kind of the same thing happens as with the HE-500. Great clarity, vocals treble and details and voices sound superb. Big difference here is that you do get a rather impactful bass. It does make the Audeze very clear and slightly more forward sounding but with vocals and classic music I can really appreciate this combo. For myself, I would still rather use the V200 or even Theorem (an awesome setup) though.
I am positively surprised with this little amp. I didn’t expect it to sound this good with that many headphones. Like I said before this amp is all about transparency, clarity, detail, vocals and treble. If you like a sound signature like the Violectric amps this unit isn’t the one for you. If however you’re into classical music or you listen to music where the vocals are very important (like Anna Ternheim, Melody Gardot, etc) you are in for a serious treat!
This amp will set you back 349£, comes with a 3 year(!) warranty and can only be bought directly from the manufacturer. Do check out their website and if this sounds like an amp you might like, you really should take them up on that 30 day trial period!