Continuing from where we left off, subsequent detailing of this post is on a R100 amp with 845 tube version. 845 was chosen for our audition model because it is the highest retail value of the tubes among the three (despite 805 version of the amp costing a higher price) and it sits in the middle ground of 211 and 805 in terms of power output. Presumably, it should give quite an accurate sense of the two.
Here is a quick video walk-through follow by the detailed write up that comes after.
First off, R100 is a beast – a monstrous amp that could actually prevent you from excitedly unboxing to try it out, solely because it is that heavy. Weighing in at around 42kg, one needs to be mentally prepared and do some rhythmic breathing in preparation of lifting it out of the thick and rugger double-boxed boxes. Please take note of correct posture in lifting it up, as it does has a serious consequence of hurting your back if not careful. To be safe, get a partner to help. I cannot stress enough, the weight plus the bulk really make it damn heavy to be carried/lifted.
Due to its weight, it is highly not recommended to place it on top of any normal TV console or media rack without proper thickness or approved weight-holding strength. Sometimes prolong sitting it on console or rack may warp them even if they may not break. Placing the R100 on the floor is the best and safest option. If you intend to move it around or plug in and out cables at the back of the amp often, I would recommend to sit it on a heavy duty platform trolley, trolley without handles, so it can look pretty as well as having ease of manoeuvre. You will thank me later.
Done with the heavy lifting, one will instantly be drawn to the thick chassis and gigantic transformers, sources of the majority of the weight. It is definitely impressive to see how well-machined the exterior is being out together. There is no one sharp edges at all, with all corners taken into consideration to be rounded off. That at least gives one a peace of mind knowing carrying it will not dig into the hands and got hurt as a result because of been weighed down.
It is hard not to notice the bulb-like tubes sticking out of the amp. Yet the brawny amp body compliments the pair of 845 perfectly. They will never be hidden because even with a cage on, the R100 will still present the beauty of big triode tubes to be admired. The cage is semi-open, guarding just the side of all the tubes, but covering the top of the preamp tubes of 6SN7s and 12AX7s.
The cage design may split preferences, as some may hope for a fully covered cage to prevent accidental scalding upon touching the giant tubes during operation. In all honesty, a full cage may not save fingers from hurt on prolong touch nevertheless, because the heat from big triode tubes will likely heat the cage hot enough to still cause unpleasant sensation. A full cage also takes away the aesthetic of the glowing tubes (which rightfully deserved to be seen), an ethos Muzishare seems to always uphold in the design of their amps.
The semi-open cage reflects a very modern approach that lends value to the design of the amp. For safe and easy removal, the cage is removed in halves, a symmetrical approach that can be seen right immediately after the entire removal of the cage. Looked metallic but they are not – the cages are fabricated from layers of supposed acrylics finished with excellent metallic and glossy spray.
Amazingly, the cages did not warp or soften despite the close proximity with the hot 845 tubes, a trait acrylic would definitely be susceptible of. It could be a more durable type of plastic I do not know, but is surely a very safe option to leave the cages on for a prolonged period without worrying them warping. Revealing the preamp tubes, a cageless R100 shows the prestigious lineup of the tubes in an orderly and imposing arrangement.
Not the biggest, but the 5U4G rectified tube seats right in the centre, leading the eyes to the rest of the tubes impressively. This visual function is almost akin to its electrical function, providing the best of direct currents to the rest of the tubes. And while we are on this rectifier tube, do understand this is a very significant implementation by Muzishare at this price point not implemented elsewhere in other brands like Line Magnetic or Cayin (except the Pro version).
A rectifier tube provides excellent efficiencies in current distributing and stabilising, allowing the tubes to be fed with cleaner and stable current for cleaner signal output. And this provides another channel of sound improvement when rolling rectifier tubes with even better vintage tubes. The presence of this rectifier tube is often overlooked but it holds a great deal to the quality of R100.
On the sides of the 5U4G rectifier are a pair of 12AX7 and 6SN7, both being very popular and wonderful-sounding preamp tubes. There are great choices of rolling them with vintage tubes, improving the smoothness and linearity of the sounds even further. Rolling 5U4G, 12AX7 and 6SN7 tubes are not particularly expensive (barring those super rare European variants) yet the sound improvement is a significant upgrade. Because behind them are tubes where their vintage counterparts will cost a huge sum to get hold on that they are better left with the stock tubes. Made no mistake, the stock tubes are from PSvane – already a highly regarded brand of tube for reissues.
Do take extra care in removing the bigger tubes of 300B and 845. There are only 4 pins in them, so the wiggly motion to remove 300B needs to be firm. 845 tubes are SCREWED ON. They are not removed the same way as the rest of the tubes by pulling them out! Remember! Hold 845 tube by the glass and firmly rotate anti-clockwise about a quarter turn. The bottom of the tube will align with the groove and then it can be removed easily.
On each side of these big tubes are the Hum Balance and Bias adjustment. By selecting to the corresponding bias group on the front panel on the left switch, we can adjust the bias of the 845 tubes to the correct value of 85mA with a test pen, taking reference from the ornate and bright VU meter in the middle of the front panel. Bias adjustment should be done preferably after at least 5 minutes of being switched on so the tubes are hot enough to show a stabilised reading. This adjustment does not need to be done every so frequently unless the 845 tubes are changed.
The same cannot be said for the hum balance adjustment though. This needs adjusting when different speakers of different sensitivity are connected, in addition to the changes of tubes. To and fro fine adjustments will have to be made on both adjustors on each side until the least hum is heard from the speaker cones by placing your ears right up to them. Complete silence is seldom ever possible, so do not get too caught up on that. As long as you heard nothing from your listening position then it is good.
The selector switch is on the front of the panel, seated to the right of a sturdy push button for powering on and off the R100. While the size of the power button is great, having the same size for the bias/VU meter sensitivity and inputs selector is admittedly less than ideal as these selector modes need switching which can be helped with a bigger knob. Presumably, aesthetic reason is probably why Muzishare implemented that, which to be fair, they are seldom touched as well once adjustment is done.
The volume knob, however, is one huge, precise, machined aluminum piece that turns buttery smooth. It offsets the symmetrical look we see on the tubes layout but nonetheless still visually balanced with help from the emphasis of space around the Muzishare logo on the other side. The exquisite and beautiful rounded VU meter right in the middle of the front panel ‘rounds off’ all things circular in front, presenting a delightful sight of high end outlook.
With the wide selection of inputs available comes the huge plethora of connections at the rear. Particularly high value in performance is the present of both balanced and phono inputs! A truly balanced connection in the entire audio chain can be greatly appreciated by those who played digital files whose DACs may have the option of connecting. This allows for a higher dynamic range as well as an even lower noise floor for a quieter background.
Phono inputs provides vinyl lovers to skip an additional phono stage and cable to go directly from the turntable to the amp with just a single pair of cable! Using external phono stage is often recommended as it performs way better than any built-in preamp most of the time. The MM phono stage in R100 not only saves the cost from getting the extra component, the shorter and more direct signal path within the internal circuit prevent additional noise to be introduced to the sensitive phono signal. One less component means one less complexity for the signal path and also additional money saved for tube upgrades for R100.
Having a balanced and phono inputs greatly heightened the performance value R100. These two components have already been seen in the KT88 tube amp X7, hence it is really not a surprise to see them in the flagship R100. They are not specifications to be taken from granted, however. None of these could be seen built together even in higher-priced amps from other Chinese brands like Line Magnetic and Cayin. While balanced and phono connections may not be utilised by everyone, they are definitely component features that future-proofed your investment subsequently if upgrades down the months or years call the need for them.
A common feature for high-powered tube amp less commonly seen in lower-powered KT88/EL34 amps is the availability of 16ohm speaker taps. Amps like R100 has the flexibility, and voltage muscles, to drive speakers load of higher impedance rating without worry of damaging them with higher currents.
Finally, how R100 sounds. Knowing how subjective this can get, the following impression is best described in terms of comparison from EL34/5881/6L6GC and KT88/6550 tubes. Basically, one word, marriage. EL34 tubes are known for the delight vocals. KT88s are so superior in power and dynamics. The 845s in R100 driven by 300B are almost like a perfect marriage between EL34 and KT88 WITH even added improvements!
Vocals are sweet and musical like EL34, BUT with added naturalism and organic touch to it. Bass and highs are ample like KT88, BUT with added tightness and more punch at the lower end and extended crisps of sparkles at the higher end where one will hope KT88 can squeeze these in further. Music just sounded much livelier with touch of realism. Power from 845 tubes does not mean the gain is high and volume is loud – in fact at 9 o’clock position is where the volume is good, anything past 10 o’clock the amp is pumping some serious juice (at Class A, this is fully expected). Every amps can drive any speakers to a loud level no problem. But power from 845 tubes come in extruding all the fine details of almost all the frequencies, regardless the volume level, in enabling the intricacies to be heard.
It is hard to find any further lacking of dullness of the music with R100 without going into the micro level of nit-picking of specific instruments or frequencies. At stock, the sound from R100 has little room for improvement. If any, I am sure we can go into these finer details with upgrades of the tubes, coupling caps, fuses and binding posts etc. But these can be reserved for the next discussion.
R100 845 tube amp is now available for order here at our product page.
R100 845 tube amp is also available for audition now . Please enquire for a time slot through the contact form here or WhatsApp me at +65 9423 9296. Give me a heads up preferably at least one day in advance.
No available stocks for immediate purchase just so to keep the upkeep and pricing low. Orders made will be delivered direct from factory to you within 2 weeks.
Available to ship worldwide, please enquire for shipping fees (I am sorry it may not be cheap due to the monstrous weight). FREE shipping in Singapore.