[LoveKnight]

If you can, please write a review of C421. I could not find any review of C421 on Head-fi yet. Thanks!

 

[guhmo]

I just ordered mine (8620)! Can't wait 'till I can be enjoying it

 

[Gofre]

Quote:

If you can, please write a review of C421. I could not find any review of C421 on Head-fi yet. Thanks!

 
My opinion won't be worth too much, I'm very much a beginner at this! I've never owned an amp before, the rig I've assembled over the last month (iMod>>C421>>Minerva Mi-3 Customs) is the first bit of audiophile gear I've ever owned =P I'll try my best to provide thoughts that people might find useful though [=

 

[Mutnat]

Quote:

If you can, please write a review of C421. I could not find any review of C421 on Head-fi yet. Thanks!

 
There are definitely some impressions throughout this thread.  I'm not an expert either but I am really loving my C421-2227.  Is there anything in particular you want to know?

 

[Puffery]

Just wanted to give some quick insight. I received my c421-2227 yesterday, up until now I have been using a cmoy BB 2.03. This is the only portable amp I can compare to the c421.
 
I have put hundred of hours into the cmoy->hd25 II combo I use in my daily commute. I listen to a lot of electronic music and the Bass Boosting feature from the cmoy produces spine chilling bass from the HD25. However, the cmoy does little to hide the 7kHz peak of the HD25 and ssss notes from Adele's royal albert hall live album are a little bit bothersome.
 
As soon as I tried the c421 I noticed a couple of things, namely:
 
The mids and highs are smooth, engaging and non-fatiguing, the spike in the HD25's treble was handled much better and it sounded very nice. The sss notes from before were no longer bothering me and I could really just relax and enjoy the music.
 
The lows are not as punchy/tight as the Cmoy, although still good. The bass seems a little loose even with the c421 bass boosting feature. 
 
The noise floor is lower/blacker background
 
The resolution, imaging and soundstage are all a good step up from the cmoy.
 
These impressions are all without burn-in so I will update if anything changes. For electronic music I might still reach for my cmoy, but for everything else the c421 will be the way to go.

 

[Mutnat]

Quote:

These impressions are all without burn-in so I will update if anything changes. For electronic music I might still reach for my cmoy, but for everything else the c421 will be the way to go.

 
I do recall mine improving with burn-in.  I've never had the cmoy to compare the bass with, but the bass is definitely more impactful than it was with the D-Zero as my amp.

 

[Hi-fi Wigwammer]

I had the JDS cMOYBB V2.03 and C421 at the same time. I found the bass much tighter and less bloomy on the C421. The cMOY sounded fantastic for the money, but the C421 bettered it in all areas. At the time this was driving UM Customs, iGrados, Alessandro MS-1i and V-Moda M80 phones.
I did find the C421 a bit bright sounding out of the box, but after 6 hours or so it improved immensely. The C421 is a terrific amp and the cMOY is no slouch either.

 

[LoveKnight]

Quote:

 
There are definitely some impressions throughout this thread.  I'm not an expert either but I am really loving my C421-2227.  Is there anything in particular you want to know?

 
Yes. I am interested in using C421-2227 with Hifiman HE-500. Does anyone try to pair them together? Thanks.

 

[Mutnat]

Quote:

 
Yes. I am interested in using C421-2227 with Hifiman HE-500. Does anyone try to pair them together? Thanks.

 
Great question!  I don't recall seeing anyone having tried it with planar headphones.

 

[Yuceka]

Quote:

 
Great question!  I don't recall seeing anyone having tried it with planar headphones.

Someone already did that in this thread. You just have to go back several pages back to find it.

 

[gelocks]

Quote:

 
Yes. I am interested in using C421-2227 with Hifiman HE-500. Does anyone try to pair them together? Thanks.

 
http://www.head-fi.org/t/575633/jdslabs-c421-preorder-is-live/240#post_8251636

 

[darren700]

listening to my c421 opa2227 right now. paired with ipod 5.5 rockbox and my monster copper pro turbines. the sound absolutly blows away the ibasso d10 that i had before. everything just sounds so much clearer and lots of bass without even using the boost. the boost works very well btw but is not needed for me because the rockbox eq is awesome. the sound is very refined in this amp imo, i am able to pick up most of the microdetails that i usually omly hear in my desktop rig. soundstage sounds great for iems also. 
 
still have to test my denon d1100s on it but im sure they will sound great.
 
doesnt have quite enough juice to drive my lcd2s but thats what my jds O2 is for. 
 
this will definately be my portable ipod amp for a long time, i love the pairing so far, especially the small form factor.
 
will also try it out with my odac when it arrives, should make a nice pair. i just wish there was a dac like the odac that can pull a digital signal from the ipod. those dacs are way to expensive right now!

 

[guhmo]

Just got my c421/8620... imaging is superb, sound is lusher and clearer all around.  Treble has improved, and my UM3X are even more revealing and intolerant of bad quality files 

 

[thrand1]

Hi everyone!
 
I was considering the O2 headphone amplifier to go with my Shure SRH-940's, but wanted something in a more portable package. From some impressions I've read in this thread, it seems like the C421 is similar to the O2 in some regards but in a smaller package. I would just like to have an amplifier to utilize with a line out dock for my iPod that doesn't overly "color" the sound, and it seems like the C421 is a good compromise when you want something similar to the O2. Are my impressions somewhat accurate?
 
Also, I have been reading up on the op-amps, if I wanted the one that would add the least coloration and provide the most neutral sound signature, is the AD8620 the way to go?
 
Thank you in advance for your helpful feedback- I have been searching far and wide for an amp that is similar to the O2 in most regards but in a more compact form factor, and I think this may be the one.
 
Thanks again!

 

[guhmo]

Quote:

Hi everyone!
 
I was considering the O2 headphone amplifier to go with my Shure SRH-940's, but wanted something in a more portable package. From some impressions I've read in this thread, it seems like the C421 is similar to the O2 in some regards but in a smaller package. I would just like to have an amplifier to utilize with a line out dock for my iPod that doesn't overly "color" the sound, and it seems like the C421 is a good compromise when you want something similar to the O2. Are my impressions somewhat accurate?
 
Also, I have been reading up on the op-amps, if I wanted the one that would add the least coloration and provide the most neutral sound signature, is the AD8620 the way to go?
 
Thank you in advance for your helpful feedback- I have been searching far and wide for an amp that is similar to the O2 in most regards but in a more compact form factor, and I think this may be the one.
 
Thanks again!

 
Yep, it seems you've found what you're looking for.  I've got the AD8620 version and the sound signature is pretty much nonexistent but for a (extremely tiny) bit of treble and bass emphasis.  It's also very compact - slightly bigger than a deck of cards - and fits under my iPod classic perfectly.