Yaqin MC-10L mk II: It's here!

[M Jarve]

Just got back from the lake, and sitting on my doorstep is my shiny new Yaqin MC-10L mk II.

I eagerly brought it in the house and carefully unpacked it. I have to say that it shipped packed as well as anything I have ever seen. I could hardly believe it.

The amp itself is much larger than I thought it was- always a good thing, though I did have to clear off the top shelf of the rack, as it is too deep to go anywhere else. Not too horrible, as the only thing that was on the top shelf was my turntable, but seeing as how the MC-10L does not have a phono input, I think I can safely store it away.

The instruction manual is short and too the point. Those of us with some experience in the hobby would hardly have to open it, though it could prove a little light for the beginner.

The MC-10L mk II shipped with a full complement of tubes (4x EL34-B and 4x 6N1), all of Chinese make, as well as a heavy-duty 14/3 power cable and a special bias adjustment screw driver. Buying it from the vendor I did, he had (apparently) matched the tubes and adjusted for proper bias. I did double check with a VOM, and after about 10 minutes of idling it seemed to be in perfect calibration. It's a handy thing having the bias pots and test-points being easily accessible from the top. I think this was one of the changes from the previous version.

I moved the VK-2100 out of the rack and hooked up my CDP and tuner to the appropriate inputs. I connected my nominally 6-ohm JVC zero9's to the 8-ohm output taps, then put on a Radiohead CD.

Wow!

Very full sound without sounding weighed down or heavy. Buttery smooth mids, and bass is rich without loosing any detail. Highs are perfectly proportioned and pretty well extended and are very easy on the ears.

This is just the initial post, and I plan on adding more as I put it through its paces. I think I can say I have a winner, though!:thmbsp:

Oh! And I have to leave very positive feedback for the seller.

 

[M Jarve]

Here's a beauty shot.

 

[wajobu]

...and it IS a beauty.

 

[ejfud]

That is a beauty Mike.

What's the power output?

 

[M Jarve]

It is rated for 52 watts per channel. I've cranked it only once so far, and it went quite as loud as I could ever stand without loosing its composure.

 

[Urizen]

Looks great, Mike.

Enjoy!

 

[wilke87]

mmmmm looks like a good piece for the next midwest get together.would love to hear that.

 

[doucanoe]

Nice looking amp Mike!

RC

 

[Holst]

Wow, very nice!!!!!

 

[Spectrum77]

Looks great. I'm very interested in what influenced you to go with that paticular model.

 

[Redboy]

Cool. I'm looking forward to your detailed review once you get some listening hours in.

 

[M Jarve]

I took the cover off at the shop this morning, and I'd like to comment on some of the internal details. I will post pictures later today.

First of all, I was a little disconcerted about the seeming hollowness of the cans over the transformers, particularly the outputs. It was my assumption that such large cans hid hideously small iron. The amp has good heft to it, so I figured that Yaqin latched to the age old trick of increasing mass by installing thick plates or even lead bars (I have seen that before). Well, I was dead wrong. While the transformers are not toroid, as one would expect from the cans, they are generously large and of exceptional quality. The individual laminations are incredibly thin, which (based on experience) is a Good Thing™.

The PCB's are thick fiberglass of the highest quality, right up there with my Adcom gear. Tube sockets are ceramic, and the output tube sockets are bolted to the board in addition to being soldered. Internal fit and finish is good with the wiring nicely bundled together and jacketed. The main power filter caps (Rubycon 105ºC rated) are mounted to standoffs and joined to the main PCB with short jumpers. All caps, save for a couple, are mounted to the underside of the boards, making ID-ing them difficult, but based on what I am seeing elsewhere, I would expect them to be of good quality.

The volume pot is a step above what I found in the VK-2100, and looks to be an Alps sealed design (or clone). Its rotation is very smooth, and from the feel of it the cap is machined from solid aluminum. The input selector also feels more solid and smooth than the VK-2100. From what I can see, the volume control operates passively, as the chain goes input->selector->volume->preamp/driver->output tubes->output transformer.

The speaker outputs are apparently WBT clones of some sort, similar to what are found on the Insignia coaxial. Input jacks are a notch above what I would consider standard A/V receiver fair- solid, but not "high-end". Certainly good enough for me, though.

The chassis itself is made of thick and sturdy sheet-metal. The top cover and rear panel are plated in a gold-toned chrome, and the front is a solid 3/8" thick slab of aluminum.

As I mentioned previously, nudies will be forthcoming when I get a chance to run home and grab the camera.

 

[M Jarve]

Nudie pic:

 

[djnagle]

I'm impressed!!! How is the sound?

 

[M Jarve]

Based on the couple of hours of listening I performed last night, the sound is quite extraordinary. As I've mentioned in the past, I have not had the best of luck with tube gear, mostly on account of trying to use used pieces that are (dangerously) out of spec. That said, the longest I lived with tubes previously was when I was running a pair of Bogen LX-60 PA amps for about a summer. They were so out of tune, and I abused them so badly that it is really not a fair comparison. However, judging it by something that I own and know, which is a ton of solid-state gear, it ranks among the best.

My personal reference for all-time most pleasurable amp was my h/k PM660. Easily, I could have lived with it forever. It was stolen, so apparently it was not meant to be, though I would say that the MC-10L edges it out just the same.

It's just right to my ears, and I can't ask more than that.:thmbsp:

But, as always, further listening is clearly called for. I have yet to put it through either the torturous OCRemix test, or the punishing 9th Symphony challenge. Those usually end up making or breaking (literally) an amp or speaker in my book.

 

[cableguy]

Very nice M...:yes: Good to see the Yaqin gear getting a little respect. I have the the Yaqin phono stage/line stage and love it...






Bill

 

[wajobu]

How does one find Yaqin? They don't SEEM to have a website.

 

[M Jarve]

I've spent the last three hours burning through the playlist, which includes the above mentioned OCRemixes and Beethoven's Ninth, in addition to some other CD's and select songs.

I've come to 3 conclusions regarding the MC-10L.

First, its power output is satisfactory for nearly any scenario I can envision with my current setup. I was able to clock a transient peak of 118dB during the crescendo just before the "Turkish March" movement of the fourth movement of the Ninth, which soundly puts it into concert level territory. Granted, the zero9's are fairly efficient at (rated) 94dB 1W/1M, but never did the amplifier misbehave or seem overly strained. Pushing it further with some very hard driving rock, I found a point where it simply ceased to get louder and the sound only broke down a small amount. Indeed, with the rock I was playing, the slight distortion actually complemented the already overdriven guitars and gave the bass a nice crunch. But these were experimental levels, trying to find the limits, and are so far beyond what the amp would normally be called to do that it's ridiculous.

More importantly, the amp seems very competent at the levels I most often listen at. I've owned many amps that played loudly better than quietly (Citation Sixteen, Crown DC-300, Kenwood KA-9100, and any Peavey amp I've used in the system). The Yaqin is perfect even with very quiet levels (tenths of a watt). This has the added benefit of giving me excellent dynamic range.

Second, one of my fears regarding using tubes proved unfounded. In my previous experiences I had noticed somewhat limited bandwidth where the highest highs and lowest lows were either diminished or simply not present. Indeed, what good is a speaker with a bandwidth beyond the human range of hearing (on both ends of the spectrum) if the amplifier cannot deliver. I can safely acquit the Yaqin in this regard, as it has proved more than capable of providing all the bandwidth I could want. It does roll off ever so slightly on the very lowest end (we're talking teens) until about 10Hz, where there was no woofer movement really at all, even with the volume quite high. On the other end, there is a perfect amount of air and extension.

Third, I cannot find a single audible fault with this amplifier. Not one. No hum, static, compression, imaging problems, anything. For my purposes, in my room, with my speakers, it is as close to perfection as I have ever gotten.

It passed all of the performance tests with flying colors.

The real test will be whether it survives the long term. I'm not talking about component or build quality here, but rather my own fickle tastes. As I am sure many of you who know me are aware, there are few components that pass this test. At this point, the Yaqin seems to have a better chance than many.


Spectrum77 asked above what made me look at the MC-10L. First, the power output seems about right for my needs. In the past I've run anything from 18WPC to more than 1000WPC, but rarely (and I mean rarely) am I running more than a single watt. If I can have 50x that, I think I'm set. Second, the EL34 output tube is a terrific tube by all accounts. It has excellent characteristics for audio, and is still widely supported today. Third, the MC-10 has gone through (by my count) 3 generations (MC-10K, MC-10L, MC-10L-2), which would indicate to me that Yaqin has matured the design. The same methods I use for choosing when to update my computer OS apply here- don't just jump in; wait for a few of the patches to come out. The one consideration that something like the 100B had going for it, in my view, was the fully dual mono design. But I had to weigh whether that was worth the additional $300 premium to me, and at this point, it was not. It is a thing to consider in the future, though. If it were practical to do so, I would have ordered both, kept them for a month, and kept the one I liked better.

Aside from any catastrophic failure or something, I think I will be pretty well set for an amp for a while.

 

[M Jarve]

How does one find Yaqin? They don't SEEM to have a website.

I bought mine on that famous auction site. They are also sold in the US under the Tonewin brand by Morrow Audio- they also service the units they sell.

Here is the official website. Beware the, err... rather poetic English translation.

 

[spaceman]

Congrats, M Jarve, it sounds like you're pretty happy with it so far. :thmbsp: I hope it brings you the same enjoyment for a good long time.