SILK MC-100B Tube Integrated Amp

Direct Price: $749

Another Special

Review

by

MARVIN BOLDEN

 

 

For those of you unacquainted with our "Stereo for Cheap Bastards", it is our just a bit quirky, snarky name for our features of stereo components that retail for $1,000 or LESS, something sorely lacking in the audio press. It's not meant as an insult and 99% of our readers get that. In fact, some of our reviewers and many of our readers via hundreds of emails have proclaimed themselves proudly to be audio CB's. This is one product that exemplifies what we're talking about.

 

 

I'm a cheap bastard; there I said it.  While I might be cheap when it comes to my hard earned money I am not cheap when it comes to sound and build quality.  Case in point, the Silk Audio Mc-100b tube integrated amp.  You probably noticed that it looks a lot like a Yaqin Mc100b, well it does because it is a re-badged Yaqin.   Brought in by a group of audiophiles (headed by Ray Siu)  in the Chicago area and made available for other cheap ass audiophiles like myself and others that put more weight into sound as opposed to cost.

 

The big package arrived in all of it's seventy pound glory measuring in at 23.6”x20.5”x14.2” and a little tough for this old frame to handle but unpack it I did.  This thing is packaged to ride, even the power tubes are protected in pvc tubes.  What I found inside was:

·Amplifier with a full set of tubes, standard 1.5m power cord, and manual;

· Hex screw drivers to mount the cover cage and to adjust bias;

· Dedicated packaging material to insure safe transport.

* Also extra fuses and a small owners manual.

 

 

Amp with included tube guard

 

I am not a stranger to Yaqin products as I owned another of their tubed integrated, (MS- 20L) but sold it because of the unconventional signal tubes used in the design.

 

 

Specifications

· Tubes: KT88-98 × 4 (Output Tubes)

                6N8P × 4 (Drivers and Cathode followers)

                12AX7B × 2 (Voltage amplifiers)

· Maximum Output:

               30W per channel (8Ω and Triode Mode)

               60W per channel (8Ω and Ultra linear Mode)

· Output Jacks: Two channels with two groups gold plated jacks

 · Output Impedance: 4Ω and 8Ω

· Input Jacks: Gold plated isolated RCA jacks, 4 groups (AUX1, AUX2, AUX3, and AUX4) on rear, and 1 group on front as the input of post-stage mode

· Input Sensitivity:

             0.25V in integrated mode (Rear input connectors)

             0.6V in pure post-stage mode (Front input connectors)

· Distortion of Harmonic Wave: ≤1.5%

· Frequency Response: 5Hz ~ 80KHz (-2dB)

· Signal-to-Noise Ratio: 90dB (A weight)

· Supply Voltage: AC 115V, 60Hz

· Power Consumption: 250W

· Net Weight: 23kg

· Shipping Weight: 30kg

· Shipping Dimension: 60cm x 52cm x 36cm

 

 

 

I'm not a big spec person as I feel that the ear test is the best way to go, besides unscrupulous manufacturers can tweak the specs any way they want to make their models look good. They are out there.

 

Features

· User-selected amplifier modes, UL (Ultra linear) mode provides greater output power and TR (Triode) mode does smooth and rich sound.

· Class A push-pull power amplifier to reduce distortion;

· User-selected pure post-stage and integrated modes;

· Utilizes the audiophile capacitors and high quality metal precision resistors dedicated for audio frequency;

· Output transformers manufactured with Japanese silicon steel sheet and oxygen-free enameled copper and high quality lacquer, which offer a wide dynamic range at full rated output;

· Independent power supply for each channel.

· Beautiful heavy duty chassis (stainless steel top, steel bottom) and aluminum panel and bezels;

· Provides user adjustable bias, test points and tool to refine bias of the output tubes.

 

Specs and features taken from Silk Audio.

 

You may wonder, who is Silk Audio?

 

Here's what they say: " We are fellow audiophiles who look for cost effective upgrades to today’s thin, shrill digital sounds from mass market gadgets.  We look for products that give that smooth, open, 'you are there' sound without having to pay a hefty price for esoteric products that might be more about hype than substance.  Engineers by trade, we believe in applying our training to select products based on sound reasoning and tradeoffs for the best value.”

 

Why buy from them?

  

Again quoting: “We are long time audiophiles that value interaction ad camaraderie with our fellow hobbyists.  We are passionate in our pursuit and want nothing less than complete satisfaction for our customers.

The products are sourced from established manufacturers and are stocked in and shipped to you from the US, after we fully inspect and test them to ensure complete functionality. By buying from us, you eliminate the uncertainty of purchasing products from overseas and we stand behind your purchases to ensure your satisfaction and enjoyment.”

 

 

Warranty

 

We are pleased to offer a one year parts and labor warranty for Silk Audio products that we sell, except tubes.  We provide service from our US location for your convenience.  Please contact us in advance before shipping units back for any service work.  Please plan to arrange for return shipping as well but we are also happy to furnish parts to you in case you prefer to perform the service work.

 

Now that all the formal stuff is out of the way I can start to have fun.

 

TIP:  ON ALL TUBE AMPS MAKE SURE YOU HAVE EVERYTING HOOKED UP TO IT BEFORE YOU POWER THE AMP ON AS NOT HAVING SPEAKERS ATTACHED MAY CAUSE DAMAGE TO THE AMP.

 

That actually applies to all amps as best practice, but tube amps sometimes are more susceptible.

 

With everything hooked up I let the amp warm up for about thirty minutes.  With the volume turned all the way down and no sources on I checked the bias settings.

 

The owners manual says set the bias to 0.5v (0.55v on the amp) but does not tell you how to set the bias.  Checking the settings, they were all off ( don't know if Silk or the factory set it or not), they were showing:

V1- 0.65v,  V2- 0.69v,  V3-0.75v,  V4-0.79v. This is not unusual because of several factors, even if the bias is set perfectly at the factory.

 

Beginners can go online (YouTube) to see how to adjust bias settings.  I suggested to Silk that they add the procedure to their owners manual.

 

For evaluation I used the stock amp with stock tubes and power cord.  The amp was placed in my system which includes Usher Dancer Mini 2 speakers(with Be tweeters), MG Audio Design Planus 2 speaker cables and Planus Cu2 interconnects.  The source was a Virtue Audio Piano M1 CDP and I used a Unison Research Nuovo integrated as my reference amp.  I also used my Belles 21a Preamp to evaluate the Mc-100B as a power amp.

 

 

Music used in the review was taken from: “Live At The Loa” by the Ray Brown Trio, “Genius Loves Company” by Ray Charles, “Warm Strangers” by Vienna Teng, and “new York Reunion” by the McCoy Tyner Quartet. And various others according to my level of “alcoholfication”....... new word.

 

Letting the amp warm up for about thirty minutes I grab a CD of an artist that I have not listened to in a while, Vienna Teng and to be more precise her Warm Strangers CD.

I read somewhere that Vienna does not think she is a good singer, well she's good enough for me and upon starting the disc from the MC-100B comes a big full sound with rich harmonics and a good pace to the music.  Miss Teng's voice was a tad edgy in the upper registers but never fatiguing  or bothersome.  Her voice was textured and sweet sounding.  Listening to the song “Passage” there was an airiness to the background and very good 3d imaging.

 

 

The mid range was closer to the neutral side of warm with good tonality and a nice attack to the notes.

 

On the Ray Charles “Genius Loves Company” the male voice has just the right amount of boldness to it with a touch o grittiness to bring tears to your eyes.  This album is a collections of duets with just about everyone with some say so in the music world, a must add to your collection.

Listening to “Fever has me snapping my fingers along with the music and nodding my head to the beat.

On “Sweet Potato Pie” with James Taylor the music is very dynamic with great depth of sound stage.

 

This CD has very deep rich tones and the tubes just highlight this.

 

The sax on McCoy Tyner's “New York Reunion" is upfront with a brash presentation that screams lifelike.  I turned my lights out and drifted off into a state of soft bliss. 

 

Track #5 ,”Ask Me Now” is spooky, don't take my word just listen for yourself.  The 3D sound stage is unreal in a good way and tonality is spot on.

 

The last CD I tried was  the Ray Brown Trio's “ Live At The Loa” as there is a track (#2 The Real Blues)where the audience starts to laugh.  There is a story behind that; when I first purchased this CD I had no clue as to why they were laughing.  Then I made some upgrades to my system (can't remember)but found out that a phone rang in the background! Ever since then I have been using this cut to see how much detail a component digs from the music.  Needless to say the Silk MC-100B played this in all it's glory.  If you want to hear this for yourself it comes in at 0.39 seconds into cut two.

 

All in all, the Silk MC-100B integrated amp is a well balanced sounding amp that is very versatile in it's use since it can be an integrated or power amp. I had so much fun listening to and playing with this amp and considering the price vs. performance this is a no brainer for someone looking to get into tubes or taking your system right up to high end status. Think of it; for the price of a lower mid-fi solid-state amp from Best Buy or such, here you have a true entry level high-end amp that will run circles around any mid-fi amp!

 

During the time I spent with the MC-100b I found some issues that either needed to be addressed by Silk or user tip to improve improved upon the sound. These are listed below.

 

More info needed in the manual.  Needs bias instructions.  Warning of loud pop when doing some switching thus user needing to switch when the amp is off.

Upgraded power cord makes a big difference.  I had on hand an entry level Audio Art Power cable, so you don't have to spend a ton of money on the upgrade;

Upgraded tubes make a difference but I would spend some time with the stock tubes before changing. Opions vary widely on different tubes, but just know that different tubes can make a world of difference in all aspects of the sound. Different tubes often equals a different amp!  I used Gold Lion Reissue KT88, new Tung Sol 6sn7gtb, new Tung Sol 12ax7, and Mullard reissue cv4004.

Great as a power amp.  Used my Belles 21a preamp ($3000) and the MC-100b held it's own.

 

I preferred triode mode for small ensemble jazz and female vocals as it has a soft and sweet sound but ultra linear mode to get that groove on. The thing is, you have a choice. Use what fits your taste or mood at the moment.

                              

 

 

As always, you need to make sure to match your speaker's sensitivity with the output of any amp. Depending on how loud you listen and the size plus how reflective or absorbent you room is, is 30 or 60 wpc enough?

Remember there are TWO modes; one that outputs 60 wps and the other, 30. In reality, the difference is only 3db, one db being the scientific increment at which the human each can detect a change. but it is enough to determine if you're listening to pure music or music that is being clipped. Tubes clip prettier than transistors, but distortion is distortion,so if your speakers are 85db sensitive or less and you listen loud in a larger room with lots of rugs, draperies and furniture, 60 watts probably won't give you enough headroom.

 

Whether you want to test the waters of tube amps, start a second system, or add tubes to your primary system you cannot go wrong with the Silk MC-100B integrated amp at its price.  It does not come with a remote, so for some that could be a deal breaker. It has value in price, build quality, and sound.  You are purchasing it in the good ole USA and don't have to worry about the risk of buying from China or the expense of shipping from Canada.  I know of a seller who replaces some caps and includes EH KT90 power tubes and charges $1800 for this amp so at $749 this is a steal. 

 

In fact, I'm putting my money where my mouth is and am going to buy one of these to be one of the amps in my stable. We never say "Highly recommended" because, well, everyone else does and it's so vague and meaningless. No one product can be "Highly Recommended" for everybody. Way too many variables. Make sense?

 

As I sit here finishing up this review I am listening to Vienna Teng using the MC-100B as a power amp and enjoying every bit of it.  Enough said.

 


 

 

 

BACK TO STEREOMOJO HOME