Disclaimer: A couple of weeks ago Wes from Tisbury Audio contacted me to see if we were interested in reviewing his new amplifier, the Challenge Amp 1. While I had never heard of Tisbury Audio I am always keen on checking out new gear, especially when it is made in Europe. At the same time this is a dual review with Sonny from inearspace.co.uk and myself. We’ve for a long time been looking to do something together et voila! Headfonia is is no way connected to Tisbury Audio and both our review samples will go back to Tisbury Audio after the review.
Normal text is from Sonny, text in blue is from myself (L.) Enjoy!
Page 1: The Amp (Sonny)
Page 2: The Sound – Part 1 (Sonny)
Page 3: The Sound – Part 2 + Conclusion (Sonny)
Page 4: L’s Take on the Challenge Amp 1
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The Amp
It’s not the biggest deal in the world but I am 100% British yet 95% of my audio collection is manufactured elsewhere. This isn’t me having a dig at stuff made overseas but there certainly is a sense of patriotism when you get a product that is made just up the road from me. That’s the case with the latest headphone amplifier I am to get my hands on, the Tisbury Audio Challenge Amp 1, it is handmade, not far from me in London, that’s each individual unit they make, hand assembled, not something so commonly done these days! This is only their second product and it is very simple in that it is a headphone amplifier, nothing fancy going on, no pre-amp settings or digital inputs, it only plays in the analogue domain and simply has just one input and output. Tisbury have decided to stick a £349 price tag onto the CA-1, which is fairly modest, for something of so bold claims. You can also grab a 30 day free trial with the amp, there is nothing like trying before you buy and I heavily recommend taking up that offer if you’re in the market for an amp, reading a review is one thing but actually trying it is another!
When I said it was simply an amplifier I was not exaggerating, you have one, single ended RCA input and one, single ended ¼ inch headphone out. We do have a gain switch as well that allows us to swap between 6 dB (2x) and 16 dB (6.3x) that has proven to be well selected, giving a solid option for IEMs and full sized headphones. It does have a couple of nifty little tricks like the LED on the front changes from green to blue when it enters playback and then when its muting circuit (handy in its own right for not blowing your headphones) is activated it goes to green. Specification wise they have some very attractive points such as a close to 0 ohm output impedance so with multi BA IEMs with crazy impedance curves you will not get a skewed frequency response and with low impedance headphones you will never suffer an over dampened bass response. It can also output some serious wattage, with this being designed with the power hungry HiFiMAN HE-500 and the CA-1 can put out 1010mW to 50 ohms and 945mW to 32 ohms so it’s no slouch if that something to concern you.
The headphone amplifier section is designed around Texas Instruments LME49600 op amp, which they have selected as the output buffer after 18 months of testing and I can imagine a fair bit of chopping and changing was done with different buffers to get to where they finished. The main focus with the parts what to minimize anything that can interfere with sound and cause degradation in any way or shape and makes it immune to ground loops.
They also put a lot of thought into the power supply with them deciding to use an off board mains transformer. The transformer gives a clean AC to the 7,200 µF capacitor bank, which in turn feeds a noiseless power supply. Having the transformer off board makes a lot of sense because it completely isolates itself away from the audio circuitry and this basically puts a full stop on there ever being any annoying humming. It also allows upgrades to be under taken, if you’re someone who feels up to it maybe, it might even see Tisbury do one them self in the future!
Maybe like me, one of the initial reasons that this product caught your eye was the enclosure, which in my experience at the least, is unique. While the main PCB is enclosed in a fairly mundane 3mm aluminum enclosure that doesn’t stray too far from what I have seen time and time again, that is then sitting in a rather beautiful wooden “nest”. It definitely grabbed my attention mainly due to it just being different and positioned next to my wooden Fischer Audio FA-011 LE headphones which are sitting on my wooden omega style headphone stand, I can indeed say I have got wood and it is a very aesthetic combination! There is one bit of the design that has really grated on my inner OCD and that is the volume pot being stuck on the left side of the front panel, in opposed to being on the far right like all my other components and a position I have become accustomed to, but can I truly even moan at that.
The solid American black walnut cradle is not just for show though; it has copper shielding so also plays a part in isolation and all the geeky stuff (and should it be any other way). That being said I was a bit disappointed to find a small dent in the wood of mine on arrival, nothing huge but clearly noticeable and as far as I am aware mine was a brand new unit. Parts throughout out this product try and stick to that British theme and if the part can be sourced in Britain, it has been. They also boast that they have stuck with top quality components using the smooth Alps Blue Velvet volume pot, Neutrik jacks on the input and outputs, Panasonic caps and Susami 0.1% thin film resistors.
It is a fairly compact item for a desktop piece, smaller than the similarly priced Yulong A28 for example with quite a thin structure but one that is a but taller that my others, which makes for a slightly stocky look. The feet have come across a bit lack luster and they are just small rubber dimples, not too dissimilar to what some portable gear like the Epiphany Acoustic E-DAC or Fiio E17 and it just doesn’t feel quite as substantial as I would like for a desktop piece.
Sound on Page 2
spudgered
Great review guys as you’ve pretty much nailed the sonic signature of this compact headphone amplifier. I acquired one recently and though it’s extraordinarily transparent, the sound is just too polite and lacking in grungy grunt (think more bass euphony) for my taste, so my classical loving father now has it. One aesthetic thing that bugged me, was the way the mains adapter pin only pushed halfway into the amps power socket, otherwise it’s a very nicely designed unit.
L.
It does do that indeed. thanks for the compliment.
It is a great unit, especially for classic and Vocals
Rūdolfs Putniņš
Looking good. I’d ditch the input caps, but that’s just me. Also there’s plenty space on the board to get a small tranny and not use a wallwart.
Opamp+buffer circuits have a very good potential to sound good.
ohm image
Tranny…
Rūdolfs Putniņš
Well, sometimes it’s good to have a tranny or two on board!
Peter Janušič
L you should have not read Sonny’s review before you made yours.
L.
Who says I did? I even had my unit before he did and made my analysis. I just wrote the full text after he sent me his review. Don’t assume. But anyway even then it wouldn’t have mattered, it sounds the way it sounds. The only difference now is I didn’t need to repeat the technical part. Anyone who has heard the unit will agree with both our opinions, I’m sure. The comment below even proves that. Just to be clear we’re on the same level, I didn’t appreciate that comment 😉
Peter Janušič
Thats what I gathered from you first sentence, didn’t assume anything. If you didn’t then I am sorry for the missunderstandment. For me your review wouldn’t be valid if you read his first.
L.
I understand, but I’m pretty sure that any reviewer has read something of the product in question before making their own review.
We’ve done dozens of double reviews here on Headfonia and sometimes the opinions of the reviewers do not match. Again, proof that reading another review first has no real impact on the review. At least imho
Dave Ulrich
You want to see a dual (or should I say duel) review where there was a difference of opinion, try this: http://www.headfonia.com/two-perspectives-on-the-neko-d100-mk2-dac/.
dalethorn
It’s a tough choice, yes? (not really). A choice between the small possibility of influence and the very real possibility of learning things that save a lot of time and work. The good reviewers will save that time when they can, then they will dig in and see where the differences are. Good reviewers have to do that anyway, since sometimes there are sample differences, sometimes an earlier review misses something – many possibilities. Since amps come before headphones in the signal path, they not only have their own sonic properties – they create different effects in headphones that aren’t always predictable in advance. So I would expect any good reviewer to have as much information from other sources and reviews in advance of doing their own review, so they can predict some of the sonic effects in advance, as a starting point. Just because you start there is no assurance that you’ll end up there. Reviews can chew up a *lot* of valuable hours, so every bit of information from reliable sources helps to get the job done.
Michael
Thanks for the review, guys. Do you think this is a good amp for Sony MA900, or Graham Slee/Yulong is better?
L.
I’m not familiar with this headphone, sorry