I think I may have purchased from the same guy, is he in Richmond Ont.? I have to say I'm very impressed with this amp as well. Not so much with the stock tubes at first. I had swapped out the 12ax7's for some mullards, and WOW! Deep smooth mids, crisp responsive top, and a really clear defining bottom. I love when you can really destinguish the kick drum from the bass guitar. I swithched out the stock kt88-98 for the smooth plates I had laying around, but that wasn't fair, because the kt88-98's hadn't opened up yet, then a couple of my kt88sc smooth plates are now toast (3 years of abuse in a bass amp) so back to the kt88-98 and they're really opening up on top now and smoothing out. Same goes for the 12ax7b chinese, it's really opening up now to, used to be like staring at a really wide wall, but it's starting to develop depth, so I'm back to the chinese tubes, they seem to bring out the most detail out of any 12ax7 I have lying around, mullard long plate, philips smooth plate (ei, telefunken???), philips 7025, rca 7025, JJ, svetlana. I hear the biggest difference will be the swapping of the 6sn7's but being a tube bass amp snob for years this being my first tube stereo, I havn't had the privelage of collecting any 6sn7's.

But yea, good build, I'll have to research internal components, the parts are appearantly audiophile quality Japanese parts, not chinese, but assembled in China. Very clean wireing, and good solder joints, internally it looks good.

So I'm sure I don't like the chinese 6sn7's in there. I finally got some GE's (I know they're "nothing special" but...) They replaced all 4 chinese 6sn7's. Now I've read allot about combining them, and so far I'm not convinced. Is that becasue the Chinese 6sn7's are "junk" and only contribute negatively...Maybe? But I wouldn't have known unless I got some other 6sn7's, because they still sound clean, even cleaner on the bottom and more lively on top, just not as nice. So now I'm waitng on my Chrome domes, Tung-sol's, RCA bottom getters, and cbs/hytrons. I'll let you know how goes er...

Also I'm trying to get some 5751's to see how they work in this amp. I'll probably try some RCA's GE's probably can't justify the sylvania's just yet.

Hey, I should rip it apart and take some pics and post the inards. I'll get on that fairly soon if anyone is interested?

Also those chinese 12ax7b in the pre are the SILVER DRAGONS echo... echo... echo... I got to say again wow, I was lookiing at them they have a double thick bottom mica, two more on top (triple mica) and the silver clips seem to be for stability, these things have quality written all over them with a higher gain than a 5751 and most 12ax7's, It's like they're taking the best of both worlds. As far as I can tell they're a high gain 5751.

I'm basically talking to myself here and I'm probably sounding like troller but I'm just excited, first stereo tube amp and all

Well my 6sn7's came in, and I've done a bit of tube rolling, I havn't given it enough time yet, but these are first impressions. The chinese 6n8p are in fact the most acurate, I guess that would mean linear, and very tight however right now I'm liking the characteristics provided by the nos tubes. I really like the CBS 6sn7gtb smooth more liquid mids detailed high's with air and detailed bottom also a very deep soundstage (favorites so far). Blended with the emphasised bass and softer top of sylvania chrome domes really warm up this amp and help tame the lively top/upper mid of the amp. I find this current combination to really tone the amp nicely without any loss of detail. I also put the mullard ecc83 back in and they seem to work better overall with the NOS tubes than the 12ax7b. Other tube to note would be the Tung-sol 6sn7gtb long bottle, very detailed, very tight bottom, good soundstage.

I have a Pre Amp that came with 3 Chinese 12AX7Bs and upgraded them to NOS Philips ECC83 Tubes and noticed a big difference in 3D image, a far more pronounced soundstage on CDs that had a forward one. More sparkle and air in the highs. Less warm mids, but incredible detailed midrange.

I also replaced 2 Chinese 6N1 Tubes in an Power Amp with NOS Philips ECC83 Tubes and got far deeper and detailed Bass. (The amp only drives my Woofers)

I did find the build quality of the Chinese 12AX7B tubes appeared high and 12AX7C's are out now.

Quote:
I on the other hand, like the Chinese 6N8P that comes with the amp. I seem to find that the tubes that are used in the design of an amp, most of the time but not always, sound the best in the amp.

Well I've given it more time with each tube, and Wow!!! I think you may be on to something there B-Bob. The 6n8p's are definatly designed for this amp, I'm writting a little review of the 6SN7's I've tried. I'll just say I've gotta have them in there somewhere.

The chinese 6n8p's bring the performance right into my living room. This provided being blended with another thicker/smoother/more liquid tube sounds very desireable to me. One 6n8p infront of the other still sounds to hard to me. It's a very fast accurate tube that thickens or solidifies rather than smoothing over transients. It is the only tube in my arsenal that brings the whole perfomance top to bottom into the living room, whether its V2V3 or V1V4.

CBS GTB very nice, I'll compare them to a clear laquer. It draws out depth and shines! It has a deep bass and clear low mids so in otherwords a deep but clear bass. Vocals can be narrow on some recordings but thats to make room for instruments of course and being a musician and not a vocalist I admire that Very Musical! It still allows the noticed transients through, beautiful extended highs. Nice amounts of air and wet slap a bit dreamy.

They are (drivers) combined with the 6n8p's I'm listening to right now.

Tung-sol GTB Compression King, nothing compresses like this tube. Quiet pasages are brought right up to hear every detail. Musicians will take turns in front with this tube. Nice mids, I would say lush on the vocals, punchy bass, and accurate highs maintain the sense of realism. Really bloomy, pumps the music out swells to the presentation.

Sylvania GTA 1953 Chrome Dome seems to have a very nice tone, but too much bass for my current setup. Warm and rich presentation from the bottom until the top when a beautifully defined treble is presented, one of the best trebles, too bad it's so quiet. This tube is best as a driver, but still a bit thick and bassy vocals/guitar down. Save for a bass shy system.

I tried the famous Sylvania Chrome dome driver/RCA bottom getter combo, and rich warm colorful detailed like watching a cartoon, but still a bit too tubey for my likes now, great for pink floyd though. Lacks treble and transients are combined in the tone for richness.

RCA GT bottom getter, Rich with harmonics, nice upper mid presence but sweet, I can see why they review it as romantic; rich, warm, sweet, and again I see why some say too sweet. But I had in for awhile before switching.

GE GTB lots of treble very clear and tight bass. Seems a bit thin in the mids, transparent. Not a good mix with 6N8p.

That's also close to my prefered order of preference give or take a recording.

IMHO

can you post a photo of the bottom insides?

I am very much interested in seeing it.

That would save me $700. Seriously. I need to see the underside of this thing. Are there circuit boards, or is it all hard wired?

Edit: nevermind. I found some photos on the internet of similar models. It is unlikely that they are using other manufacturing methods for their similar gear, so I surmise that what I saw on the internet is similar to what is in this given unit.

No pics yet, I'll do it in January, Christmas is a busy time of year.

Oh, I'll be editing those review or adding to them as time goes on. Just for kicks, I put some of the thicker/warmer sounding tubes in then swithched it over to UL mode, and that cleaned them up beautifully. Allot tighter in the bottom and seems to space things out a little better. So for example now the RCA/Sylvania combo is clearer and tighter sounding, not overly bassy and thick. And those highs are coming through better.

Hi. How would you compare Yaqins to the better known brands, i.e. PrimaLuna, Cayin, etc.? Thank you!

Hi i bougth mine on ebay,but it makes a lot of low frequent sound. I also bougth a bailiyin el cleaner that does not have much effect on the noise.If any one can give me some adwise I would be happy.starting to get a little sceptical about yaqin.Is it good and comparable to well known brand by price and sound? Thanks

hi guys. im a new bee here. im also a proud owner of yaqin mc-100b. i have owned it for almost a year now and i can't be happier

it's a very impressive unit, definitely BEST bang for your bucks. looks like well built apart from loose on/off switch (doesn't stay in its place properly, a bit wabbly).

everytime i heard my music through my paradigm ref studio 60, i just love it more and more.

anyway, to answer the Q above, as far as i know, almost all valve amp will emit very very slight low hum. this is how they work apparantly (please do correct me if im wrong).

i have upgraded my power cables and use belkin power isolator to make it as quiet as possible and it is even quieter than my solid-state power amp.

I just got my MC-100B a few weeks ago, and I really love this thing. I don't have any hum at all, even when the volume is really high. I also don't have a problem with a loose power switch - mine is quite solidly mounted. This is really a sweet amp. It drives my relatively cheap and inefficient consumer grade speakers to insane volumes even in TRIODE mode. 30 amps in triode is just amazing.

The only problem with the amp is that mine has capacitors without a cover over the top, and two of them are at 247 volts. Some of the amps have caps with the plastic film that covers the entire cap including the top, and some have the top wide open. A little RTV silicone and a brush fixed this. But it's something to be aware of if you have cats or parties with drunken and/or none too bright friends

Overall, this has been the best purchase I've ever made. I've only had consumer grade equipment before... the sound out of this thing is just so much better it's hard to even describe.

Charles

I have the sylvania chrome domes on order... has anyone installed a diy IR volume control with a motorized pot on this thing yet? Something like this:

http://electronics.dantimax.dk/Kits/Control_boards/index.html

Charles.

Okay, so I've had a chance to swap some tubes. I really like the Electro Harmonix 12AX7's in the preamp. They really toned down the brightness and gave the music a much warmer feel. The treble is no longer harsh at all, and detail is still quite good. With the stock tubes some songs with lots of cymbals sounded... unpleasant. Okay for a while, but then I had the urge to skip tracks. The Electro Harmonix 12AX7's made such songs much easier on the ears.

But the biggest change came from the Sylvania 6sn7 chrome domes (circa 1948). These tubes sound AWESOME. The music is so much... richer and fuller, and the bass is really tight and thumping. And movies! Sci fi and action flicks are spectacular. Explosions really rock the whole house.

This has transformed my amp from merely sounding good, to sounding absolutely spectacular. You have to try the chrome domes. (I paid $75 for a matched quad delivered to my door from eBay. Electro Harmonix preamp tubes were $10ea from a local guitar guy)

Charles.

just thought i`d add a bit about my yaqin and my system. i`m new to tube amps so this was a jump into the unknown for me.

for a few years i`ve been thinking about tube amps. i read up about the yaqin mc100b and made my mind to get one. i liked the look of it too. i luckily managed to get one secondhand. when i got it the tubes needed replacing so here i am in the great tube hunt! it still had the chinese tubes in it. so after pretty much days and days of reading write ups on tubes i made my mind up. the 1st tubes i got were shuguang psvane 12ax7-t. i thought the standard tubes that came with the amp sounded nice enough even though they all needed replacing but these tubes made very nice improvements all round. deeper and more solid bass. more of a real  sounding midband. i mean by that more lifelike. the highs were sweet and open and extended. voices are amazingly real. i was startled by dave gilmours voice on the track "smile" off the cd "on an island" just hanging there between the speakers as if he were there in person! my friend found that very eerie too! there was nice detail and depth from all instruments being played. the only thing was though was the soundstage. it was all there but not much seperation of performers and instruments. you can follow all the instruments but it`s as if they`re all bunched in the centre!

next tubes through the post were electro harmonix kt88eh x 4. very nice! more depth, more bass, nice solid midband, more detail! the soundstage opened up too. i listened to the same gilmour track "smile" and was taken back by the extra detail and depth to his voice! more body!  hearing him breathe! on the cd as a whole there was such nice bass depth, tone and detail. very very slightly on the warm side on the whole from highs to lows. i got to say the highs totally amazed me on the steve hillage cd "green" they reach the sky with a sweet and extended frequency that is extremely pleasant on the ears and sooooo pleasing! i`ve never experienced high frequencies like this! the sound as a whole is also very transparent. although this is my first tube amp, i have a strong feeling it will be my last! i`m not parting with this! it`s responded superbly to the tube changes and i`m lucky so far to say that the psvane/electro harmonix work well together. i have 4 sylvania 6sn7gtb green label 1951 tubes on their way to me and also a matched pair of rca 6sn7gt`s on their way too. not sure of the year on the rca`s. i intend to use 2 sylvania`s and 2 rca`s mirrored. apparently they work well together. i just hope they work well with the psvanes and electro harmonix! we`ll see!

the system i have put together also seems to work as a perfect synergy. the front end is the gorgeous tubed musical fidelity nu-vista 3d cd player and the speakers used are the quad 12L2. cables used are chord chorus 2 interconnects and 2 lengths of chord oddessey 2 speaker wires and using chord oddessey link wires for the biwire but i`ve just ordered another 2 lengths of oddessey 2 with spades at the amp end to biwire the speakers properly. i also put sorbothane feet under the amp and cd player which tightened up the sound oddly. wasn`t sure they`d work but they do seem to. another thing about this system is it`s lovely for late night listening too. you still get everything when you play it quietly. soooo detailed!

i`ve thrown everything at this system! acdc, joe bonamassa, pink floyd, foo fighters, chillout cd`s, eva cassidy (xrcd version), holst planets and a whole load more and this system just smiles through them all!

for me the true star of this awesome system has to be the yaqin amp! sooooo versatile! i`ve listened to ulta linear mode and pure triode mode. triodes really nice but for me ulta linear is the way to go! more solid and real sounding. the changes made with the tubes so far have been tremendous and so far has transformed this amp from being pretty good to amazing and i still have those other tubes on their way to me as well! to say i`m excited at the prospect of those coming through my door any day now is an understatement! the fact you can add a pre amp too makes this a special amp. i might go down the internal upgrade path instead of getting a pre amp. i got mundorf silver/oil caps in sight! but stuff like that can wait. i just want to enjoy this system for the next few years before i consider upgrades and changes, but the point is, is it`s all there to do at your leisure or as your pocket dictates.

this is a stunning amplifier!

just to add comments about upgrades i made

i added another 2 lengths of chord oddessey speaker wires so i now have my speakers properly biwired and i got my sylvania gtb`s and rca gt`s through the post. a very good combination! the soundstage is deeper, wider and tighter and very solid. the sound is a very appealing warmth with plenty of detail and beautiful highs. the sound is very immediate too but never in your face. tonaly it`s spot on for me and very holographic. this amp has come a long way from the sound of the standard chinese tubes. like i said, the standard tubes to my ears sounded really good, very clear. this amplifier has responded really well to all the changes on the tubes. it`s hard to say which tubes gave the biggest impact to the sound. i guess the pavanes made the biggest change to the sound and all the rest of the tubes built on that. on this amp and this system, the tubes i now have fitted work extremely well. next year i may try the brimar 6sn7gt black glass tubes. i`ve heard some nice things about them. but thats the only change in the combination i`ll make.

i`m also considering upgrading to the chord anthem 2 interconnects. more detailed, will add air around the performers and they will lower the noise floor and also enhance the bass. i`m seriously now thinking of getting the mundorf silver/oil caps and fitting them in to the amp. the tubes made a big difference to the sound and the mundorfs will only enhance it all further.

this is my first ever venture into the world of tube amps and it will be my last. this whole system works unbelievably well together. holographic and real to the extreme. it has the most pleasing bass i`ve personally heard. on some recordings, voices sound eerily real! on pretty much all recordings the voices are always amazing but on some it really stands out! the soundstage and imaging are jaw dropping! and soooo much detail!

i`ve put together one amazing system and at the beating heart of it all is this versatile yaqin mc100b amplifier! one hell of a toy!

wow!!! i ordered a matched pair of brimar 6sn7gty/cv1988 after reading about them and what a difference they have made! all i can say is there is so much weight to the sound now and the soundstage is pin point accurate. i have them in v1 and v4 with sylvania 6sn7gtb`s in v2 and v3. this is a beautiful match! this is the best i`ve heard from this amp now.

i also bought a secondhand pair of chord anthem 2 interconnects and these have lowered the noise floor and added bass. the sound is just amazing. the bass is nice and deep and the sound in general has a gorgeous moreish warmth. the extra detail on offer is stunning! i`m hearing even more things in recordings i never knew was there and there`s more detail in voices and instruments. this is amazing stuff! i doubt i`ll bother doing a capacitor upgrade now. i`m just so pleased with the sound that comes out of the speakers and i think its just fine as it is. i just can`t stop listening to cd`s now. the only problem if you can call it a problem is late night listening has gone out of the window now because of all the extra weight to the sound and the extra bass. but i think i can live with that. the nice thing about getting everything secondhand is it`s all already run in! the only thing new in this system are the speaker wires and they`re well broken in now, not that i heard and real difference to when they were new.

i`ll keep all the tubes i`ve bought that i`m not using for a few years then sell them! make a bit of money hopefully!

I am thinking about getting the Yagin MC 100b and have a bunch of questions I hope some of you can answer.

First off I'll be running large speakers, a pair of JBL L7's rated at 91db efficency, will the amp be able to crank those speakers up really loud if needed?  I currently use a HK PA2400 amp with 120 watts per channel, and with that I can get the walls to shake when watching movies, is the Yagin that capable? 

Second, would it be better to use my current HK PA2400 amp to drive the base on the L7's and then use the Yagin on the mids and highs?

Is so, then how does one govern the volumn on the base?  Separately?  Or can the Yagin control the volumn for both?

Third, since there's not enough output in the rear for all my gear, can I use a Y RCA connector to run two units off one output as long as only one unit is working?

Thanks for the responses to my questions.  I watch movies with my current system as well as hard rock to smooth jazz, and want a system with warmth but also want to be able to drive the speakers when needed, so I'm hoping that Yagin can do that.

91 dB efficiency might be sufficient. But from my measurements this Yaqin only delivers 30 watts, not 60 as specified. I have relatively small room with 90 dB rated speakers, and I can reach 98 dB at listening position. This is loud enough for most acoustic music, but you won't reach rock concert level.If you are interested read my notes about it here http://www.audiokarma.org/forums/showthread.php?t=429993