2. amps-preamps
  3. 1325547060

yaqin mc100b tube rolling

hi all,

ok i`m new to tube amplifiers, in fact i`ve not owned a hifi for a good few years so i thought i`d take the plunge and see whats out there.

after some pretty exhaustive auditioning and plenty of reading and research i decided to go for the yaqin amp. the rest of my system consists of.....

musical fidelity nu-vista 3d cd player
yaqin mc100b amplifier
quad 12L2 speakers sitting on target R5 stands
chord anthem2 interconnects
chord oddessey2 speaker wires (4 lengths)

i bought the amp secondhand and the tubes were worn and needed replacing.

i bought 4 x electro harmonix KT88EH`s
2 x shuguang psvane 12AX7T`s (grant fidelity matched)
i`ve bought a variety of 6sn7`s to test out. i bought several matched pairs. brimar 6sn7gty/cv1988, rca vt231, rca 6sn7gt, sylvania 6sn7gtb and shuguang 6n8p.

so far the brimar/shuguang combination is the best sounding. they give an excellent and pin point soundstage, the sound is very clear indeed, you can hear quite a way into recordings and there is very good depth to the soundstage. voices are solid and natural. acoustic guitars have a ring to them. dave gilmours guitar work on the track "where we start" off his solo cd on an island has a really beautiful tone to it with an added very slight warmth and depth. the brimars have a clear yet warm sound and sound slightly laid back. the shuguangs have a very clear up front sound and the combination of these two tubes is a pretty good matching. my only quibble is i could do with a bit more bass. i`m not saying the bass i get is inadequate, i could just do with a bit more.

i tried the brimars with the rca vt231`s. not a very good matching! way too much warmth going on here for me and lacks excitement. less detail too. mind you i will say, i listened to the xrcd recording i have of eva cassidy`s songbird and this cd has never sounded so good! but pretty much everything else i listened to didn`t really impress me that much. not sure what classical music sounds like with this combination. i didn`t think to listen to any!

i tried the sylvania gtb/rca 6sn7gt combination. not as much clarity or information as the brimar/shuguang combo but still very very nice sounding. nice deep bass, very nice soundstage, natural sounding voices. all in all a very nice sounding tone all the way through. beautiful and sweet top end too.

i tried the rca vt231/rca 6sn7gt combination. not really all that impressed. lots of information but just a bit dull sounding. lacks a bit of get up n go!

that`s as far as i have got so far in tube rolling. anyone else that has this amp have any tube combinations that works for them? also as i am new to valve amps and tube rolling, are there any other 6sn7 type tubes i should look out for?

many thanks in advance guys
grayf
8 responses Add your response
chrisbcrttr
1 posts
 
I have had this amp for over 10 years and when I bought it new I immediately swapped out all of the tubes with Tung Sol 12ax7’s, Tung Sol 6sn7 and Genalex Gold Lion kt88’s. Recently I have got the itch to roll some tubes and I thought I would pass on some info. I kept the Gold Lions in while swapping out the 6sn7’s with some nos Sylvania tubes, they were not as good as the Tung Sol reissues so I swapped back. I tried some Mullard 12ax7’s and they sounded as good or better in tone and clarity but were noisy so I swapped back. I then tried some Psvane 12ax7’s and found the mid range lacking but highs were slightly extended versus the Tung Sol, I swapped back to the Tung Sol. Next and I think finally I ordered some Sylvania 6sn7 “bad boy” tubes and I know that’s a marketing term but these fit the description. They are the only tubes that have improved the sound. Beautiful mids and highs, bass has more definition, less muddy. Overall a balanced sound with wide soundstage. I am very happy with it so I thought this may help someone out with tube selection.

Other equipment...

 I am using the Yaqin MC100B as an amp with a Krell kav 300il as the pre amp, so I can have a remote. Speakers are Monitor Audio Silver 6. Clearaudio concept MC turntable. Clearaudio Basic Plus phono amp.
Oppo bdp 105d
Mac mini for streaming Tidal
Richard Gray’s power company 1200 custom power conditioner
All cables are Cardas.


olds442111
2 posts
 
Has anyone tried any varieties of 12at7 up front in these amps? Or just too little gain?
scutterflux
14 posts
 
Nice! I also have one of these amps and it started me into tube rolling, Your fav is probably very similar to what my favorites are as well... Let's compare.

shuguang treasure kt88-z black bottle x 4
VS.
Shuguang Solid Smooth plate gekt88

rca vt231 grey bottles x 2 in v1 and v4
VS.
RCA 6sn7gt black plate bottom getter same spots

brimar 6sn7gty/cv1988 black bottle brown base x 2 in v2 and v3
VS
Tung-sol 6sn7gt (Mouse Ears, more on the smooth, well rounded imaging and ambiance with excellent detail and focused midrange...)

telefunken 12ax7 smooth plates x 2
VS
Sylvania 5751 grey-plates 80's... beat the telefunken and the sylvania 5751 black plates, rca's mullards etc, I highly recomend trying these ones out, they may give you the bass you're looking for and are still a very tight resposive tube like the telefunken...

Anyway havn't rolled in this amp since I came up with this combo as well years ago...

Enjoy
grayf OP
61 posts
 
oh and guys i`ve started another thread about upgrades for this amplifier. if anyone has modded this amp internally with capacitors or anything else i`d like to hear from you :)
grayf OP
61 posts
 
hi all,

sorry for the lengthy delay. i`ve been tube rolling this amp and now have the perfect combination and boy it`s transformed this amplifier into something extremely special!!! ok the combination of tubes are .....

shuguang treasure kt88-z black bottle x 4
rca vt231 grey bottles x 2 in v1 and v4
brimar 6sn7gty/cv1988 black bottle brown base x 2 in v2 and v3
telefunken 12ax7 smooth plates x 2

i swapped the brimars and rca`s around and they now work extremely well together. all the tubes work so well in harmony together! the sound is now perfection from top to bottom and the soundstage and imaging is breathtaking. so is the bass!!! so deep and warm with slam when needed. the sound is smooth and crystal clear all the way through and natural. the soundstage has perfect width and depth.

my whole system has perfect synergy too. i couldn`t be happier!

i hope this has helped others with this amplifier too :)

the tubes were pretty expensive but this amplifier can take it in it`s stride! a real bargain amplifier!
grayf OP
61 posts
 
just another update. well i don`t know if it`s the psvanes 12ax7t`s or the brimar tubes still breaking in but wow! i have about 120 hours on the psvanes and about 30 hours on the brimars. the brimars are nos tubes. it`s like someone switched the light on to reveal bucket loads of detail. all instruments are like someones shining a light on them! there`s extra weight to everything too. there`s a very pleasing sense of depth to the soundstage. the highs really do reach the sky and the bass is rich and floor shaking deep! this is the combination i`ll be staying with now.

i did try the rca vt231/sylvania combination and very nice too. the sound is lighter and livelier. awesome detail and very atmospheric and a very big soundstage.

personally i prefered the brimar/sylvania combination. there`s a weightier sound on offer with darker tones which i find so satisfying. all my favourite cd`s hit the spot when i listen to them. not so good recordings don`t sound so bad either. late night listening has suffered a bit though because of the bass which is a shame, but i can live with that with whats on offer.

the rca vt231/sylvania combination is extremely good too and i`d say it`s more a matter of preference rather than which one is better. they both have their pro`s and cons

i used the same 3 cd`s to check the sounds of the tubes
grayf OP
61 posts
 
hiya drumhead, i did a little more tube rolling today. i tried the brimar/sylvania gtb`s. i have to say this is the best pairing so far and i have a little extra bass and the top end is nicer. yes the midrange here and with the shuguangs really is satisfying. the really nice thing with the sylvania`s is i`ve managed to preserve all the detail and clarity that i liked about the shuguangs. i think my tube rolling is now over with. i`m so happy with the sound that comes out of my speakers. i`m not so sure i can improve on the sound now although i am thinking about changing some capacitors inside the amp that i know will make a difference. i`ll probably get that done in the summer. i want to get the amplifier serviced about june time so i`ll get the capacitors done at the same time. that`ll give me a good chance to research what capacitors are out there that will enhance the sound of this amplifier.

i have to say that i`m amazed at this amplifiers capabilities. considering i payed about £300 secondhand for it, the sound is incredible! i know i`m using a high end cd player but this amp allows it to sing and also to be fine tuned using tubes and cables.

i`ve never heard a soundstage as strong as this. i`ve always gone for solid state in the past and i honestly can`t remember why i opted for a tube amplifier in the first place. i know the looks of the amplifier are first what caught my eye. i think it was when i visited forums to find out more about it is what hooked me. lots of folk saying how good it is. well i have to say that all of the solid state amps i`ve ever owned in the past are just no comparison to this. i`ve mainly always gone for exposure or cyrus amplifiers but they really don`t compare. not even close in my opinion. tube amplifiers going by this one are a very very different listen. i really do wish i`d discovered tube amplifiers years ago! i don`t think i`ll ever be parting with this amplifier!
drumhead4
20 posts
 
I'm no expert in tube rolling but I commend you on your thorough research and picks. It sounds like you zero'd in on your fav. tonal balance minus low end with the brimar/shuguang. If this is giving you a satisfying midrange (the most important factor) then adding a quality sub will fill in the bottom perfectly.
Log in to respond
More to discover
80x80
Ayon Audio Conquistador Preamp
80x80
Dan D'Agostino Momentum HD
80x80
Classe Audio Delta Pre Preamp