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
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.
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!
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