The midrange and treble are all of a piece here. They flow smoothly and naturally without any loss of detail as a result. Obviously, there is no harshness in the midrange, nor anything piercing in the treble, but, as I said before, they are never dwarfed, or buried in any way by the bass. There aren’t any worrisome spikes in the sound to contend with. Vocal presence is also (I am getting tired of writing this word) natural. In truth, the CTH retains the sound of whatever headphone you plug into it; it just adds a small touch of tubey smoothness to the sound, and weight to the bottom end. For those who use tube amps as a form of EQ, this is not your amp. For those who, like me prefer their amps as complimentary to their headphones, this is a most wonderful amp.
The soundstage is nice and open, with good width and depth. Its resolution and micro detail are shockingly good at this price. For those wondering how this pairs with Massdrop’s SDAC (and this is a fair question as the CTH does sometimes drop with the SDAC built in), they make a very fine, musical combination. The Grace Design SDAC, reviewed here, is a killer, low budget USB DAC, with an off the charts price/performance ratio. Pairing it with an amp that is also a price/performance beast is a no brainer. However, the CTH is resolving enough that, when I switch over to my X-Sabre Pro, the differences in micro detail and soundstage are easily noticeable. The CTH can scale surprisingly well. However, if looking for a great sounding, DAC/AMP combo on the cheap, the SDAC and CTH make great bedfellows.
Comparing the CTH to the very nice SMSL T1 I reviewed some time ago, the CTH has more weight in the bass, is more open sounding and is more resolving than the T1’s amp section. The T1 does come with a good built-in DAC, although I do prefer the similarly priced CTH/SDAC combo a bit more. The T1 does have more input and output options.
I suppose I need to confess one more thing before I continue: I hate tube rolling. The way I see it, tube rolling is an expensive crapshoot. Spending how much time and money trying to find just the right tubes that will make your system sound its best… Well, if that is your idea of a good time, great! I do know people who enjoy buying, mixing and matching different tubes; I am just not one of them. Part of the problem for me, and why I often shy away from tube amps, is that the amp never seems to come with a tube that can show the amp at its best. The way I see it, you should be able to use whatever tube comes stock with your amp, to show how good it is. If you just spent $250 on an amp, you shouldn’t need to double that, just to hear the amp can really do.
This might actually be my favorite thing about the CTH: it comes with a tube that sounds like it was designed specifically for this amp. The Electro-Harmonix 6922 is an amazing match, and like I said, you could swear the amp was built around this tube. What’s more, the EH 6922 is a very inexpensive, current production tube. It can be had for peanuts at any store that sells vacuum tubes, and as it is still being made, it is unlikely to disappear. Now, for those who do like tube rolling, knock yourselves out. And, if by chance you do find another tube that really does well in the CTH, please let us know. For those like me, who don’t really have the taste (or the bank) for it, you don’t have to worry.
There is only one strike that I have to levy against the CTH, and it really isn’t even that. It is just stopping me from giving this a universal, to anyone, anywhere, recommendation. The CTH, like most amps that sport vacuum tubes, is happiest when driving high impedance headphones. Now, the CTH sounded fine to good with everything I tried with it. The Hifiman HE-560, Hifiman HE-400i, Base Audio G12, Grado SR-80e, and Mr. Speakers Aeon C (if something doesn’t sound good with the Aeon C, then that something is broken) all sound good with the CTH, but the star of the show here is clearly the HD650. As I said before, it has tremendous weight in the bass, but it does so without losing its normal pace (which, admittedly isn’t very fast, but it certainly isn’t any slower). The whole thing sounds clean, very detailed, and insanely musical. The CTH even helps the HD650 open up a little bit. If you want to spend as little as possible and get a damn near end game amp for the HD650, this might be it. I just wish I had other high impedance headphones to try out on the CTH. It should be a great budget amp for the HD800.
But, getting back to that one strike, if you are looking for an entry level amp that does everything equally well, this isn’t quite it, as it does clearly show preference to the high impedance crowd. Just to reiterate, it doesn’t sound bad with anything, it just isn’t quite the perfect all-a-rounder. I am just not happy with myself if I don’t say something negative.
So, yeah, the CTH is another easy recommendation for me from Alex Cavalli and the good people at Massdrop. For those who share my preference for what a tube amp should do, pair these with the HD650 (or the Massdrop 6XX, same thing), and enjoy your time in heaven. The CTH retails for $249 and is available now at the other end of this link: