Willsound MK1 Rev. 2 is another popular budget earbud on Head-fi and on Earbuds Anonymous group in Facebook. I purchased the MK1 and MK2 both in their second revision together.
http://www.rholupat.com/custom-earphone/willsound-mk1-new-batch.html
Since most will be curious to know the difference in sound signature between the two, the review will use the same tracks that were used in my impression of the MK2 Rev 2 and there will be references to the MK2, when necessary.
I had a conversation with the creator of the buds and understood that each Willsound earbud uses a different driver. That makes the MK1 and MK2 more cousins than siblings 
. This makes me appreciate the effort gone into identifying the right driver and tuning for a unique sound signature for each earbud in the Willsound family
Unlike the MK2 which look plain in their white coloured housing, the MK1 Rev. 2 comes in a premium looking red colored housing with top notch paint quality. The faceplate is metal as well and adds to the premium"ness" of the earbud. The cable is neon red color and is quite flexible; in fact, the cable is very likable and they do not cause any unwanted microphonics while listening.
The earbuds have a nice, branded, zippered case and come with 4 pairs of of-white foams. The foams are of good quality as well.
Foam Matching
I use all most earbuds without foam covers - I feel that foam covers, thick, thin or with a hole in the center, affect the airiness of the highs and sounds claustrophobic. While the MK1 is still fine with the thin foams, I do not prefer the thicker foams included with the MK1. Thin foams complement the warmth that is on short supply and add a decent amount of weight to the mid bass, while not impacting the mids and highs.
My impressions to follow are on mixed use of thin foams and without foams.
So how does it sound?
Here's the setup for my evaluation - FLACs (16/44.1, 24/48 and 24/96) on my LG G6 with ES9218p DAC SOC and Tidal Desktop app on my laptop.
The other key factor that is to be considered while reading my opinion below is that earbuds may sound different to different individuals based on the shape and size of your ears and how the earbuds fit and how they are positioned and your hearing sensitivity itself. So while I may be able to hear a good amount of sub-bass, others may not; while I may find the highs a bit hot for longer sessions, others may find it perfect.
Track 1 - Shibuya by Covet - The warmth is just right on this track - bass guitar is where it usually belongs and not in the front of soundstage like in the case of the MK2; the snare drums sound exceptionally good with controlled reverb and when the medley of the snare drums, bass guitar, cymbals and electric guitar play together, the separation at the lower mid frequency does not have sufficient air between the instruments and the texture of the bass note does not come out clearly (Maybe a slower bass attack/decay? Will test this further in the tracks below) On the other hand, the hi-hats and ride cymbals have a brilliant, satisfying sparkle and a nice airiness to the sound. There is no bass bleed into the lower mids. The sound-stage depth on offer is limited, so I don't feel like I'm on the drummer's seat, but more like an audience watching a band play.
Track 2 - Two Against Nature by Steely Dan - The first thing you'll note on this track is the brilliant rendering of the cymbals like the case of the earlier track. Width on offer is quite good and separation is decent too. The rendering of the layering of music is not as highlighted as in the case with the MK2. The bass note has a good texture but decay feels a bit slower. Vocals are recessed a smidge but many listeners may like it this way
Track 3 - Royals by Lorde - This track emphasizes the observation mentioned above - clean bass with no impact on mids. But then it also shows that the decay of bass notes are on the slower side and the texture is impacted - there are times when the bass texture is hardly audible. While the MK1 offers a clean balance of sub and mid bass frequencies, the slowness of the driver in the lower bass frequencies does have an impact on its bass performance. On the brighter side, this won't be noticeable on most pop tracks.
Track 4 - Madness by Muse - The perfect track for bass and vocal quality. This track reveals something new on the MK1 - the mids, around the 1KHz range is a bit amplified which brings about a nasal quality to Matt Belamy's voice. Also, I suspect that there is dip around 500 Hz to keep the bass clean and separated from the mids which can highlight to the nasal quality of the sound as the warmth is kept in check. While the bass texture is well rendered for the most part, there are times when it get a bit busy and the rendering suffers. Width and separation on offer are good. When the track gets busy, separation in the sub 2KHz frequencies take a hit.
At around the 3 minute mark when the track unleashes
euphoria, the layering is strictly average and bass texture takes big hit. It did not give me enough satisfaction and this is my favorite part in the entire track.
Track 5 - The National Anthem by Radiohead - The MK1 struggles a lot on this track. While the bass riff is nice and meaty and treble extension and airiness show up nicely on this track when it is simple enough at the neginning, this track highlights two things where the MK1 flounders - sound-stage depth and separation when the track gets busy. The width, in fact, is wider than its cousin, the MK2, but the sense of depth is quite limited. With the extended highs and well controlled mid bass, I expected the MK1 to ace the separation stress test at the 3-minute mark of the track, when every random instrument is given an open invitation to the cacophony party. While the MK1 does try to give a sense of the happenings of the track, it just could not keep up with the happenings on the track. While you can forgive it for such lapses, I strictly don't recommend it for serious listening. For regular, simple tracks, the MK1 showcases a likeable signature with extended highs.
2 Bonus tracks here to reaffirm the finding - Sound-stage depth and Bass speed
Bonus Track 1 - Bubbles by Yosi Horikawa - The rendering of depth is decent, the pebbles and balls dropping on the ground are rendered well, but the 3D feeling is not present as the lower frequencies are rendered just average and also at the 4-minute mark, when the track gets busy, depth and separation suffer.
Bonus Track 2 - Get Lucky by Daft Punk - This track is all about speed, texture and separation. Bass attack has decent speed, but decay is slow, but it is good enough not to impact the tempo of the track. This is one track where I feel the tempo is impacted significantly due to bass speed. The slowness reported above was observed in the lower bass frequencies and this track relies mostly on the mid and upper bass frequencies and hence the rendering of speed and texture are quite decent. Separation is good for the most part, nothing new from what has not been stated already. Pharrell Williams' voice has a nice texture to it and is reasonably forward.
Update (11-Jul-2018): Recently tried
Seinabo Sey's Breathe on the MK1 - the bass performance was below par, a bit boomy and was lacking in texture. Tried the review tracks again and updated the rating to reflect my opinion.
Conclusion
Willsound MK1 offers sufficient performance for a regular listening session - clean, likeable sound signature with nice extension towards both end of the spectrum. The more you use it, the more you will appreciate its sound signature - handles most genres of music quite well. More demanding users may find themselves wanting a bit more out of it.
