Need info Yaqin MC-10L

rromeo923

Just got a Yaqin MC-10L off of Audiogon.

Came packed ok but did not include a manual or power cord.

I want to try this out and can't:eek:

I do have a power cord from a NAD 3080 (125v 10a ) that fits but not sure if will work w/ the Yaqin and I don't want to blow this thing up right off the bat.

This is my first tube amp and I am not sure about a few things.

What are some basic tube amp rules. I know I am supposed to not touch tubes with out gloves.

How long do I need to warm up at zero volume?
Should it have speakers plugged in initially? Should I have say a cd player hooked up to it initially?

Tube Biasing??? Ahhhhh

Any info would be great.

Thanks!

heiney9

Any IEC power cord will work.

Try not to touch the tubes with bare hands, if you do it's not the end of the world.

ALWAYS have speakers hooked up when running a tube amp

Make all gear connections (ie, cdp) before you power up the unit.

IIRC, the biasing on that unit is straight forward, unless it's an early model. You will need DVM and you will need the bias voltage values, usually in millivolts. Lots of stuff on the internet about the MC-10L so it should be easy to find the biasing info.

I would wait atleast 2-3 minutes before playing anything thru it.

It will take about an hour for it to sound its best, so if in the first 15 minutes you aren't happy with the sound, wait about an hour.

Don't leave tubes unattended for a long period of time, especially on a new to you piece. (if they are powered up, obviously)

It's really no different than regular gear other than proper biasing and making sure to have a load hooked up (speakers).

The bias, once it's set, shouldn't need any attention for awhile. Also don't assume the previous owner had it set right before he boxed it up and sent it to you, the new owner. I assumed that once and it cost me a brand new 50's black plate RCA power tube. I was not happy!!!

Since it's a new to you piece once you set the bias I'd check it in a few hours to make sure it hasn't drifted and then check it every couple days for about a week. If it doesn't drift, then you're good. If you have a hard time keeping proper bias, then that's a red flag there is some sort of issue.

H9

heiney9

If you do find right after you power it up you need to power it down, wait about 5 minutes, unless something catastrophic happened upon power up. Tube amps don't like to be powered up and powered down quickly, that's how things break.

Now if you power it up and a tube blows or you realize speakers aren't hooked up, etc, etc. Power it down right away.

heiney9

It also appears there is a special tool to adjust the bias, not sure if that's the only thing that can be used. I'd contact the seller and ask why the instructions, power cord and bias tool weren't included (I am assuming the bias tool wasn't included)

H9

heiney9

See post #49

http://www.audiokarma.org/forums/showthread.php?t=176912&page=4

Bias voltage is between 350-400 mV, if it were me I;d shoot for 375 mV, it may fluxuate a bit so get it close. If it bounces around a little bit that alright.

rromeo923

Thank you very much for all the info.

The Bias tool was included.

Gonna hook it up and see what happens.

Wish me luck!

rromeo923

Success!!!

Awesome!

First listening experience - Lee Oskar- My Road Our Road (Highly Recommended)

Sounds so good! I am in love :redface:

rromeo923

Wife- That looks dangerous :eek: Why do you have to have an amp that looks like that????

That sounds good.......

That is about as good as I am gonna get from the wife

nspindel

You're using it with those new sda's of yours? 1C's if I remember?

Very nice. Good power makes sda's sing. Tubes make them get up and dance!

rromeo923

Yes the 1C's sound better than ever.

I am gonna sell some items and then I will be looking to you for some advice on the crossover mods as I believe we have the same type of 1C's with the two crossovers per speaker.

This is so much fun!

nspindel

Congrats. You're hooked....

If I were to do my xo's today, I'd be starting with a pair of gimpod's boards, that's for sure.

polkfarmboy

I too own this yaqin mc10l and although it sounds great with my polks it sounds as if somthing is missing from the top end with the martin logans hooked up. I will be swapping out the cheap stock $5 tubes that have came bundled with this tube amp but other purchases have put me back from doing so at this moment

I think the yaqin really shines bright with male and female vocals from the more classic tracks. I love some janis joplin and neil diamond or a lil bit of bowie from this tube amp . The sound is great so I am really looking forward to upgrading the 6n1 preamp tubes to really enjoy more diverse music .

My first impression when I fired up the yaqin was the low end authority it produced . I could feel the power just blasting out of my 8" woofers and the floor was rumbling . I think the yaqin is a super sleek sexy looking tube amp that looks great and adds a touch of class to any av rack youl place it in . I paid a lil under $600 shipped for mine from tubstien on ebay and I think its a great bargain for what it can do

One thing that has not been mentioned is that under the power cord socket you will find a lil drawer that pops out containing a spare fuse if you ever blow one . Just like the wise Heiney9 states above that you gota be careful with the powering up and down of tube amps because this is how I blew my first fuse a few days after buying . i was lucky to have my good friend michaeljsda guid me through the location and installation of the new fuse

nspindel

Wait till you start rolling tubes, that's when you'll really appreciate what they're all about, because you'll see the differences imparted by changing nothing but the tubes. Then you'll find your favorites that are complete magic.

rromeo923

After some internet research it seems that most people are mainly concerned with rolling the 6N1 tubes. I saw some Russian 6N1P-EV on ebay that are relatively cheap. Anyone have good experience with these?

Also are there local (US) stores or internet sites to buy from that you could recommend? The Russian places take a month to ship.

heiney9

rromeo923 wrote: »

After some internet research it seems that most people are mainly concerned with rolling the 6N1 tubes. I saw some Russian 6N1P-EV on ebay that are relatively cheap. Anyone have good experience with these?

Also are there local (US) stores or internet sites to buy from that you could recommend? The Russian places take a month to ship.

I use 6N1P-EV's in another tube amp and they are very nice. The older the better. I use pairs from the mid 60's and early 70's. Be sure they are "EV's" and have the "OTK" stamp. I look on Ebay later and see if I recognize the seller I bought from and let you know.

I would also change out the power tubes (EL34) and the best I've found for new production are the Winged "C" SED's. They are really starting to jump in price lately, but they are a great EL34 tube that have a reputation for lasting a long time.

H9

nspindel

I have four Winged "C" 6H13C's that I'm going to be selling. Don't think they're compatible with EL34 are they?

rromeo923

I have been running this amp w/my 1c's at 4 ohm. I tried out 8 ohm and I believe it sounds better.

At certain points I am not sure how music can sound better. Loving this.

nspindel

There's a thread somewhere that has a recommended SDA playlist. You should go have some fun with that...

rromeo923

I told my son (16yrs old) to come and listen to Rush- The Trees. Like most 16yr olds he was a bit "busy" and said " Dad, I've heard that song before, a lot!"

Well I convinced him to take a seat in the sweet spot and turned it on. He says, " That sounds good. Actually that sounds Perfect! It's like your at a concert. You can hear everything! Then he didnt say another word and just listened.

All of this is worth every penny for moments like that.

nspindel

What are you using for your source?

rromeo923

Laptop w/ Creative Sound Blaster X-Fi HD

flac vinyl rip Hemispheres 1978 - Mercury / 9100 059 / UK First Pressing

engtaz

Congrats on the tubes. My son loves music also.

nspindel

Do your 1C's have the RD-0194's yet or are you still using the SL2000's? Easiest way to tell is that the dome of the tweeter will be translucent plastic on an SL-2000 and will be black silk on the RD-0194.

Just trying to set your expectations on what your next round of spending looks like. Many advise that you take your time and do one mod at a time, and listen along the way so you understand the nuances that each mod introduces. It's good advise, although I never followed it. I did tweeters, crossovers, inductors, spikes, and a custom sda cable all at the same time. If I were starting now I would do all of the above, plus dynamat, rings, and Tony's boards, plus either the mortite or some other replacement for the gaskets. I'll be doing round two of 1C mods at some point to add the later items, except the boards.

If you wanted to do all of that at once, you'll spend about $300 or less for the XO's, depending on the caps you go with, although Sonicap has a 20% off sale going on right now. The tweeters will cost you about $200, if you haven't gotten them yet. If you wanted to do posts, there are a wide range of choices at various costs. I would at least advise you to get a single pair of binding posts to make a custom sda connector, and then use some decent speaker wire in place of the stock cable. A full set of Cardas posts including an extra pair for an sda connector would be about $120 if I remember. Inductors will run anywhere from around $60 to $150 depending on which you go with, if you decide to do the inductors. The rings and the boards will be around $200 if I remember correctly. The dynamat, and mortite, and jbweld mods are fairly inexpensive. You can pick and choose and adjust from that list, but I just wanted to give you a sense of what the expense of modding the speakers can start growing to. The full suite of mods with top notch components can start pushing $1000. But remember, these are speakers that cost $1500 in the 1980's. Not sure what you spent for them, but think about what $1500 in the 1980's is worth today, and consider that when you're finished these will sound way better than they ever could have in stock form. Not trying to spend your money, just giving you some thoughts to stew over.

One thing to consider before ripping into them is that you would have a hard time getting your money back out of these speakers if you try to sell them. If you find the right buyer who appreciates the value what you have done, you can certainly recoup a large part of your investment. But the main justification for spending the money and doing the work is if you plan to enjoy those speakers for years to come. If that's the case, then give them the workover they deserve!

One last comment... I'd consider upgrading your source a bit. I'm not a big fan of using a computer as a source, but I can certainly see the appeal. However, I think you'd be quite pleased if you stepped up your dac a little bit. You can certainly go out and spend four figures on a dac if you want, but there are some really good pieces that can be found in the $300 range that I think would bring more out of that Yaqin amp and your SDA's. The Creative Labs is a nifty little product for digitizing analog recordings, but I think you could do much better for playback with this new system you're building.

engtaz

Here is a link to one persons setup of this unit.
http://homepage.ntlworld.com/lez/YAQIN%20MC10/A%20LOOK%20AT%20THE%20YAQIN%20MC10L.doc.

rromeo923

I have the Rdo 194s in and have been very pleased with that upgrade. I also did the mortite.

Not planning on selling. They are already too awesome! I am thinking caps and resistors would be my next best bang for the buck.

I thought the new boards didnt work on the two crossover 1C's

engtaz- I looked at that link and most of that info is so far over my head. You people are geniuses!

My older son (23) already has his own polks Rt8's!

rromeo923

I biased the tubes to around 365 a few days ago. I checked them today after about 10hrs listening and they were all higher around 500. I put them back to 365. I will ck again in a few days.

I did go from 4ohm to 8ohm at some point. Would that make a difference?

rromeo923

I also read that the two middle tubes 6n1p are more important than the ends in terms of sound.

Could I just change those ones?

heiney9

rromeo923 wrote: »

I biased the tubes to around 365 a few days ago. I checked them today after about 10hrs listening and they were all higher around 500. I put them back to 365. I will ck again in a few days.

I did go from 4ohm to 8ohm at some point. Would that make a difference?

I don't think so, but I would bias with whatever speaker output you are using. 500mV is pretty high, I'd keep an eye on it because that could indicate an issue. You'll want that sorted out before you roll some nice power tubes. You say all 4 were at 500? Always re-check bias after about an hour once the tubes have settled in.

rromeo923 wrote: »

I also read that the two middle tubes 6n1p are more important than the ends in terms of sound.

Could I just change those ones?

Sure, start with those, etc. They certainly are inexpensive enough to try. I think you'll like them. If you really want to open the door I *think* you can use the ECC85/6AQ8 tube in that position.

Let me do some research.

H9

heiney9

You'll need to do some research to see if anyone has used am ECC85/6AQ8 in place of the 6N1. Yaqin states a 6N1 or 6922 or ECC88. I have a Dared piece that uses 6N1 which is equivalent to the ECC85/6AQ8 but NOT the 6922 or ECC88. So there is a discrepancy there.

rromeo923

H9 I certainly appreciate all your very helpful info. If we ever meet I got the beers!

TheH

Yaqin MC_10L is a great amp, I'm impress with how good mp3 audio sounds with this amp, I've had my amp for about month and a half and today I received a quad of Russian 6N1P-EV's NOS.

What I'm not 100% sure is if there is re-bias to be done when changing the original Chinese 6N1 with Russian 6N1P-EV or anything else, or if re-bias only applies for the EL34B Output tubes?

Can someone confirm this?
Thanks!