[Currawong]

Kingwa mentioned in an email that he's looking for a commercial box for the C2C, so hopefully he'll find a nice one that is also lighter.

 

[Seba]

That sum was made of the unit + shipping + PP fees. I got 20$ back from Kingwa because the shipping was cheaper than expected.

My amp has been in Finland for a couple of days but it's stuck in customs so have to still wait for a couple of days more.

 

[cnocmoy]

Quote:

Originally Posted by Currawong /img/forum/go_quote.gif REIZ Audio C2C: Little Dot MKV (Head-fi review): Source: MacBook Pro (24/96 output) Van den Hul Optocoupler Lavry DA10 (in single-ended mode most of the time) Interconnects: SAEC 1903 6N RCA (A Japanese brand I'm sure hardly anyone has heard of.) Van Den Hul The Thunderline XLR Headphones: Markl/Lawton Audio Denon D5000 ("MD5000") - 25 Ohm Sennheiser HD650 with Zu Mobius cable - 300 Ohm, older version. MB Quart QP55 Ultimate Ears Triple.fi 10 Music: Everything except techno, rap and metal. All ALAC at 44.1kHz except music from Linn Records which is 88.2 or 96. Back when I stepped into the head-fi world, I wanted to see how far I could achieve the audio nirvana I had enjoyed at home with speakers, but without the 5-figure sum that it would require and preferably without getting too far into 4 figures. To that end, aside from with headphones, I went down the path of two devices that were "flavour of the month" on head-fi, the Zero DAC and Little Dot MKV. Through the former I gained a little education in some aspects of audio electronics, including opamps and from there, discrete opamps (HDAMs). As we discovered the HDAM and how it could transform the ZERO DAC, finding its original maker, REIZ Audio/Audio-gd, also lead me to discover its maker's line of headphone amps. The Little Dot MKV sells for around US$300, so upon discovering that it might be possible to do better than it for around the same amount (All discrete for $330? Yes please!) I took the plunge and bought REIZ Audio/Audio-gd's C2C, as I had superseded my Zero DAC with a Lavry DA10, and the HP amp built into the Lavry was well and truly a match for the MKV. Arrival: Delivery of the C2C took longer than the MKV, but that was because Kingwa (of REIZ Audio/Audio-gd) insists on burning in and testing each unit for 100 hours before sending it to the customer. This meant about a week after payment that the unit was shipped, making almost 2 weeks before arrival for me in Japan. Little Dot seems to have organised themselves well with packing, having a box that was designed to fit the MKV. The C2C (along with some HDAMs I'd ordered) arrived VERY well packed....in Styrofoam. Great effort, but wrong material. I grabbed a toothpick out of the cupboard to get a tiny piece of the Styrofoam out of one of the XLR sockets before hooking it up. Whilst not up to the exacting standards of US or European manufacturers, the MKV nonetheless is a nicely assembled piece of kit. Regrettably I bought mine at the height of its popularity and there are a couple more rough edges than other people's photos seem to show. The C2C on the other hand, resembles a DIY amp in all but the circuit board. There is no nicely stencilled lettering, merely what looks like a price sticker to indicate the input selector switch and the fit and finish is a little rough, with screw holes and the volume knob asking for slightly better alignment. The volume knob on the C2C also was a cheap aluminium thing with no markings, except a dot drawn on with a marker. I immediately replaced it with a more solid $20 unit which you can see in the pictures. Both amps are dual-mono in construction, with the MKV having individual toroidal transformers for each channel and the C2C having a single, shielded transformer in the corner. Both require that you order them with the correct voltage. The C2C is a little interesting in that solid silver wire is used for hooking up the jacks and volume pot. Otherwise, both use Alps Blue Velvet units. First thing's first and both amps get my Denon's plugged in and the volume turned up with no music playing. A tiny amount of hiss comes from both, but, contrary to popular belief, the MKV doesn't have hum with low impedance headphones. The one time I had buzz with the MKV, it was a fault of my source. With my HD650s plugged in, with both there's just blackness. Both amps offer dual inputs, though in the case of the C2C, the second input is balanced. While a balanced input for a single-ended output is considered pointless by some, the Lavry is a balanced DAC, I'll have to ascertain whether any benefit is gained by using it. In the case of the MKV, the two inputs are switched by pressing a button, which switches using a circuit. The C2C on the other hand, has a regular switch. In testing the MKV with two inputs connected, if a signal was being sent to one input, it could be heard, faintly, which the other was engaged. While not great, it wasn't a show-stopper for me as whatever I wasn't using as a source at any time was switched off, which I imagine would be the same for most end users. One of the first things that is noticeable about listening to music via the MKV is that the volume knob seems to always need to be a bit higher than seems good. If the source is something with a proper line-out signal, it's not an issue, but in the months I've had it, I've had at least one source where I could max the MKV's volume for regular listening, and I don't listen to music seriously loud, ever. The C2C, on the other hand, is fine for listening at 9pm with my Denons and 10-11pm with my Senns where the MKV is somewhere around 12pm onwards. From 12pm things start to get painful with my Denons. In both cases, my Lavry is set to a volume level of 37 (out of 56). Music impressions: I'm listening to Binky's Dream from Dave McLaughlin's Extrapolation and can hear the electric guitar and saxophone notes echoing across the studio. Switching to something better recorded, The Gotan Project's Paris, Texas, the notes on the piano at the end -- you can hear the tonal changes in the strings as the notes decay. Finally I head on to Jeff Buckley and I'm lost once again in the beauty of his singing. However, through the MKV, these fine details just aren't there. Tom Waits, with his horse voice, sometimes projected with the aid of a megaphone woudln't have struck me as a singer that would benefit the aid of high fidelity delivery, but for all his weirdness, the C2C has brought out the beauty in what he sings more so than the MKV did. My Denons, which go low, possibly too enthusiastically, giving everything body and impact, even when I didn't have it with other headphones, are sent by the C2C even further and with more authority into the low regions, something I had not yet encountered. Cranking up that old standard, The Crystal Method's Community Service II, the deepest bass, which through the MKV I felt needed to be tighter, is delivered with authority and control through the C2C. Three and a half minutes into Keep Hope Alive, I've now discovered a very subtle buzz to that very deep bass note, and other subtle notes played down in that region I hadn't noticed before. I have to give credit to the Lavry for the revealed detail, but for the delivery it's the C2C. I plugged my Denon's and Senns directly into the DA10 to be sure, and the bass, nor its authority just wasn't as present as much as it is through the C2C. Finishing up the album with the remix of the Smashing Pumpkins 1979, the cascading waves of sounds just take me away.... This prompted me to grab my old MB Quart QP55Xs, with their drivers the size of dinner plates (well, not literally) and see if the C2C could manage better at pushing their huge drivers better. The 55Xs have a much flatter and duller soundstage than my other cans, rather reminding me of mid-range AudioTechnicas but with a far better soundstage from the thicker pads. They also have a rather anaemic bass and high treble. The bass can be fixed by removing a piece of felt from the foam in the back of the cups, but they are still a serious pain to drive. The result was, well, like none of these problems mattered -- treble was nice and smooth, the cymbals from Coltrane's Dear Lord coming through as, well, cymbols, the sax sweet and the bass on any heavy-duty music delivered with the same authority as with my Denons. Now nothing will save the mid-range of these cheap cans, but the C2C passed with flying colours, confirming what I'd already discovered. If I were to attempt to describe the "sound" of the MKV, it would be that it's neutral -- it asks little and imposes nothing in return, except the natural effect of increased soundstage and separation where there was a lack of amping previously, such as with my Zero DAC or Apogee Duet. It might be as much due to the choice of opamps in the Zero -- two MC33078Ps. I experimented throwing in both LT1364s and LM4562s and the results were respectively too much of an un-emotional sound with the LT1364s and the "loudness button" effect of the LM4562s. The C2C is another matter. After much thought, the best word to describe it would be "silver". It pushed my silver-cabled Senns into the territory of being a different headphone to what they are plugged into the MKV, my Corda Move or the Lavry. It achieves exactly what I wanted of an amp, something that would take a top source and deliver it with exacting detail across the spectrum, without falter. At one point, while moving equipment around, I thought I'd both have another listen with my Apogee Duet as the source, as well as experiment with interconnects. The C2C revealed that, indeed, the Duet wasn't quite up there with the Lavry, lacking that last bit of detail and musicality. A lesser pair of ICs was the same, again, the last bit of detail wasn't there. Finally, switching the Lavry to balanced mode and hooking in an XLR pair of Van Den Hul's The Thunderline (you have to admit that's an awesome name for an interconnect) the result was quite clearly a slightly smoother sound, something VDH cables have a reputation for in all but their top models. But what if....? As one of my primary reasons for buying the C2C was it being all discrete, an idea occurred to me: How much of the difference between the amps was opamp vs. discrete? What if I were to put two HDAMs in the MKV? Could REIZ Audio/Audio-gd's very own HDAM modules upgrade the MKV to match the C2C's performance? Opening it up, I found just enough space to fit two HDAMs with extension wires, so into it two of REIZ Audio/Audio-gd's Earth modules went. Van Halen's Year to the Day, which I selected for the guitar intro was my first test. The buzz from the guitar amp, clearly spatially separate in the C2C, sounding like it were sitting away and to the right, was less distinct through the MKV, more as if it were a buzz in the recording or equipment than from Eddie's amp. The sound of the piano at the end of The Gotan Project's Paris, Texas was still lovely, but that last detail of the decaying tones in the strings that the Lavry extracts wasn't there in the MKV. Having not listened to it through better equipment, I was pleasantly surprised when I switched to the C2C to hear the changing tones of the strings as the notes decayed. Jeff Buckley, Hiromi, Sara K, Coltrane and others told the same story, that the lovely separation, space and details instruments and voices have through the C2C just isn't quite there in the MKV, even with HDAMs, and less so stock. It rather reminded me of the differences between the DA10 and my Apogee Duet, or between a good set of interconnects and one of the cheap sets I plugged into test the difference -- the detail just isn't there. The C2C's "I'm going to grab your bass and everything else by the balls and show you what it's made of down to the last hair" just isn't there either. Sticking two HDAMs into the MKV certainly makes for an improvement to it, but the MKV feels as if it just doesn't have the power to drive headphones to their best regardless, either low or high impedance. Some of the explanation for the performance in the C2C appears to be what is more commonly known as the Burson Audio Buffer. The actual buffer circuit is made by REIZ Audio/Audio-gd (or at least designed by them as they sell the boards for DIY) and adjusts the impedance of a source to match that of the receiver for better SQ. 6moons wrote in a review of the stand-alone unit: "The influence on the sonic presentation brought about by the inclusion of the Burson Audio Buffer is pretty much summed up by the statements above. Yes, the buffer subtly increases the perceived impact of transient attacks and seems to extend the treble up further into the 'air' regions. Bass also tends to bloom and acquires a heavier punch as well as a little more perceived depth." This goes a long way to explaining why this inexpensive amp sounds so good. When I first ordered the amp, Kingwa from REIZ Audio/Audio-gd told me that I'd need a good source. I thought at first he was assuming I was going to use the Zero as my source, but after reading the Positive Feedback review of the buffer, his comment made more sense. You need a good source with a proper line out, or the amp could end up sounding horrid. Conclusions: So where do I begin? The Little Dot MKV has been a staple of Head-fi since Penchum's review, being a good design and good value for $300. With the C2C, with its hand-made case, I feel I must be like those people who built themselves a DIY amp to exceed what could be achieved by a better commercial amp for far less money, except that I didn't build the amp myself. I'm using a DAC that's 3x its price as my source and I'm glad I am! Most of all, I'm thoroughly enjoying all my music over again, the DA10 and C2C revealing that last detail I've been searching for throughout the entire sound spectrum. If anything the C2C is too good and I should be comparing REIZ Audio/Audio-gd's cheaper SS amps with the MKV, for if the C2C exceeds the MKV in every way, then I wouldn't be surprised if their cheaper amps will match or better the MKV, even with a HDAM upgrade!) for less money. After I wrote up most of this review, I took my gear around to LobsterSan's office for a 2-person mini-meet so we could try out headphones we'd never heard before. Afterwards I thought some more about the C2C's performance with various headphones. I realised that where the C2C seems to shine is with low impedance cans and seriously wished that I had a pair of AKGs handy, as this could be the perfect bargain solid-state amp to bring them out of their shell considering how it brought out my Denons. As well, it would be interesting to try Grados and Ultrasones with them for the same reason. I did, however have a pair of Ultimate Ears Triple.fi 10s handy -- and yes, I think I'm onto something, as the result with them was a sound that was much fuller than what I was used to out of my Corda Move. So, allow me to go as far as to say, if the C2C were made in the USA or Europe and sold in a beautiful, perfectly made shiny box for $900, people would rave over it. As it is, it's a $330 Chinese hand-made HP amp, but one with quite a bit of interesting technology in it that is exceptional value. The Little Dot MKV is a decent amp, better than, say, the HP amp built into the Zero DAC or Apogee Duet, but now I know I can do a lot better for the money, if I don't mind the box it's in. Finally: Thanks for reading my first full review on Head-fi.

Hi,
great review, very informative...thank you.
PS
can you get this amp with a 240V power supply? i.e to work in the UK or does it have a 110 power supply and use a stepdown device?
Thank you for helping a headphone novice!
Kind regards
John.

 

[DaMnEd]

Quote:

Originally Posted by cnocmoy /img/forum/go_quote.gif ... can you get this amp with a 240V power supply? i.e to work in the UK or does it have a 110 power supply and use a stepdown device? ...

Yes, you can. Audio-GD price list

Look at the first column:
Quote:

(110/120/220/240V)

 

[wae5]

“One of the first things that is noticeable about listening to music via the MKV is that the volume knob seems to always need to be a bit higher than seems good. If the source is something with a proper line-out signal, it's not an issue, but in the months I've had it, I've had at least one source where I could max the MKV's volume for regular listening, and I don't listen to music seriously loud, ever. The C2C, on the other hand, is fine for listening at 9pm with my Denons and 10-11pm with my Senns where the MKV is somewhere around 12pm onwards. From 12pm things start to get painful with my Denons. In both cases, my Lavry is set to a volume level of 37 (out of 56).”

When I read this I hooked up my DT880, MS1 and HD600 to the LD MKV and none of these needed the volume control to go beyond 8:00 on a clock face or 10 on my MKV volume scale for normal listening levels.

 

[iTetragrammaton]

Does the C2C headphone input accept standard headphone jacks, or only balanced?

 

[DaMnEd]

Quote:

Originally Posted by iTetragrammaton /img/forum/go_quote.gif Does the C2C headphone input accept standard headphone jacks, or only balanced?

Your question is kinda confusing because inputs and headphone jacks don't mix, you have RCA and XLR inputs, and then the headphone jack output, so I'll try to answer by covering all inputs and outputs the amp has.

The C2C accepts both XRL for balanced signal or RCA for unbalanced signal input.

The headphone jack ouput is a standard 1/4" phone jack, looks like a Neutrik Locking 1/4" Phone Jack

This amp is not a balanced amp, but it accepts balanced sources.

 

[iTetragrammaton]

Thank you - I meant the headphone output, of course

The locking mechanism on the output confused me into thinking it was balanced.

 

[Seba]

I just got mine and first impressions are that Denon's truly need a proper SS-amp. Everything sounds more exciting, faster and clearer than with my previous tube-amp.

I also use the volume at 9 O'clock with Denon's, it seems to have plenty of reserve left.

Oh, and it doesn't look bad either IRL. Looks very high-end with thick front panel and full-aluminium enclosure.

 

[bardoo]

Sounds good. Keep posting on your impressions when you get some more hours on it. Considering this for my D2000 so I'm really curious what you think.

 

[Currawong]

An interesting thought, since you mention Denons: I bought a set of mulga cups from Lawton Audio for my MD5000s, as they very slightly damp the bass and treble. The result was a mid-bass bloom which was slightly unpleasant. We're talking around the 125Hz mark (when I experimented with the iTunes equaliser). I put the fibreloft that had been in the original cups with the Markl mod (my pair was one of the original modded versions with fibreloft in the cups) and the bloom is fixed. However, when I mentioned this to Markl, he reckoned this was most likely due to the amp or source. This might tally with the effect of a boosted bass one gets with the impedance buffers.

I forgot to add: I've changed the title and name to just "Audio-gd" as Kingwa tells me that's the correct name to use for his company that he uses for export.

 

[Currawong]

I've finally gotten around to posting pictures (in the second post) including the circuit diagram, for those interested.

 

[johnwmclean]

OMG That’s looks like a lot of amplifier for the asking price!

 

[Seba]

I'm only waiting for Cardas solder and then I can start Zapfiltering my Zhaolu. I have Audioquest King Cobra XLR's waiting impatienctly for connect those two.

 

[dario]

How would compare the C2C with a good valve amp?
And for the 650 would be better the C2C or a valve amp?