The Final Production Version
Early in January I posted an impression of the C421 on Headfonia’s Facebook (www.facebook.com/headfonia) since I was enjoying the amp very much and wanted to spread out the word. I wanted to do a review then, but since the enclosure was to receive some further treatment, I thought I had better wait until the final enclosure is finalized.
Eventually the enclosure is finished and I received the final C421 from John. The black aluminum enclosure has now received a brushed hairline finish, and a matte black finish instead of glossy on the prototypes. It’s nicer looking, but still not a big improvement as a whole. Looking at the amplifier as a whole, I think the enclosure design is the one area that still needs an improvement. It’s not terribly bad, actually, as the whole thing is still cased in aluminum, precise cuts on the front and back plate, and high quality jacks and switches. But a nicer case is definitely welcome. Lieven told me he likes the look of the C421, but we all know I have a better sense of aesthetics than he.
Aside from the case, the other significant changes to the final version is the lower gain levels (2.5x versus 3.5x gain), different brand gain resistors, different brand 3.5mm jacks and toggle switches.
Comparison to the Ibasso D-Zero
The C421 is a clear step up from the D-Zero in terms of sound quality. The D-Zero may be the better value amp as it comes with a USB DAC for $109. However, if judging solely from the sound quality, I would go for the C421 clearly for the superior midrange, an overall better treble/midrange/bass balance, and most of all the superior soundstage.
Comparison to the Headstage Arrow 3G and 4G
The Headstage is a nice amp and is still the slimmest one of the bunch. Build quality wise, it is still better than the C421 (in fact I think the D-Zero also has a better build quality than the C421). However I always find its soundstage to be quite flat. The 3G variant has a dark tonality and was quite full sounding in the mids and lows. The 4G version changed things a little by adding more treble to the mix, and you get a slightly more airier sound. Still it didn’t improve on the overall soundstage performance (airy sound is not the same as true three dimensional soundstage), and the treble area was dryer in comparison to the 3G.
In many areas I find the C421 to be better sounding than both the 3G and the 4G Headstage amps. The soundstage performance was clearly better, as it possess both width and depth not heard on the Headstage. Midrange was also sweeter and clearer, the treble more airy while still very smooth. The only advantage the Headstage has over the C421 is in the bass section, where the Headstage has a more proper bass punch.
Comparison to the TTVJ Slim
One of the highlights of the TTVJ Slim is the midrange, but I think the C421 has exceeded it in midrange quality. I also enjoy the mildly darker and more laid-back presentation of the C421 better than the TTVJ. However, the TTVJ still wins when it comes to overall dynamics, micro detail, and bass impact. The TTVJ sounds like a bigger amp than the C421 is.
Comparison to the ALO Rx
Like the TTVJ Slim, the ALO Rx also sounds bigger than the C421 is. Better dynamics and bass impact than what I get from the C421. However, the ALO Rx is known more for its spacious sound and powerful bass impact, but not so much for a full sounding mids. Again in this case I think the midrange of the C421 keeps on winning me over. Also, while the ALO Rx ultimately has a wider soundstage, the C421 has a better depth and ambiance over the Rx.
Comparison to the Objective 2 Amp
This is the only non-slim amp comparison in the list, but I know that a lot of people have been asking for this comparison. The O2 is a better amp technically, with a blacker background, wider soundstage and clearer instrument separation. The C421 wins on midrange quality and portability factor.
I enjoy being able to recommend good sounding gear to people, even more if it happens to be affordable to the majority of my readers. Prior to the C421, the JDSLabs Cmoy is perhaps the one amp that I made the biggest number of recommendations for. One reason is definitely the $60 price tag, but even more is the fact that the Cmoy actually sounds very good. However, it was still limited in terms of features.
It would be nice to have something that sounds like a Cmoy in a slimmer package, and not only with a recharging circuit but USB-based charging. Many great amps like the RSA-71A fall short when it comes to day-to-day usability because they don’t come with recharging circuits, so USB charging ranks very high on my list (most of us have too many gadgets, each requiring its own dedicated charger).
As I mentioned earlier, I told John that I would’ve been very content even if the sound is only on-par with the Cmoy. (In case you’re wondering, the C421 makes the Cmoy sound congested so it is clearly better). It’s true that initially I just saw the C421 as another amp maker’s effort to expand their product line. Now that I’ve lived with it for 3 months, I’m definitely going to make a lot of recommendations for this amp.
On the picture gallery: I apologize for the lack of comparative pictures to the other amps.