MrSpeakers Alpha Dog Review (and comparison with HD600 and K701)

Introduction

The MrSpeakers Alpha Dog is a new modded T50RP headphone which costs $599. It uses a 3D printed cup which results in a number of sonic improvements over other T50RP mods such as a more neutral sound signature and less cup resonances. It is a fully closed headphone which Dan Clark (the creator of the Alpha Dog) claims to provide “an audiophile open headphone experience”. For this reason I will be comparing the MrSpeakers Alpha Dog with two open headphones, the Sennheiser HD600 and AKG K701. Can the Alpha Dogs really provide an open headphone experience

More information available on the MrSpeakers website:

https://www.mrspeakers.com/index.php?route=product/category&path=69

Specifications

Alpha Dogs (T50RP) Sennheiser HD600 AKG K701 Frequency Range 15 Hz - 35 kHz 12 - 39 kHz 10Hz - 39.8kHz Impedance 50 Ω 300 Ω 62 Ω Sensitivity 98 dB 97 dB 105dB Maximum Input Power 3000 mW 200mW 200mW

Jargon Glossary (written by kstuart)

I will referring to these definitions when using audiophile jargon in this review.

Jargon glossary written by kstuart:

http://www.head-fi.org/t/676095/mrspeakers-alpha-dog-revealed-the-worlds-first-production-3d-printed-headphones/3045#post_9897359

Soundstage:

this is exactly analogous to a stage at a live performance. You can have six people in a band who perform at gigs in various places. In one big arena, the stage will be 50 feet wide and the keyboard guy will be way left, the drummers will be way back in the center, and the bass guy will be way right. Then they go to a small club, and the whole stage is only 20 feet wide and shallower, and you hear the same instruments but they all sound closer. Different headphones and electronics present different sizes and depths of stages, due to tiny distortions of the signal.

Imaging:

this is how accurate the positions are presented within the stage. Really good imaging (such as with the SRH-1840) not only presents the different instruments clearly within the stage, it also present a 3D image of the instrument (provided the recording is that good).

Openness:

this is the subjective feeling provided by the headphone system, of being in an open space where one is surrounded by sounds. Even though it is a different use of the word "open", coincidentally it is a quality usually found in open headphones and not in closed headphones. Within those categories, headphones vary in their amount of openness.

Air:

this is a subject audio evaluation term that has some similarities with openness, but can still refer to one instrument on one channel. Air usually implies a clean and strong high end presented with extreme clarity, so each sound is presented in a way that sounds "effortless". If an audio system cannot produce the sense of "air", then it probably cannot produce any sense of "openness" (the latter referring more to a general sense of space rather than the sound of any one instrument).

Test setup

PC (foobar2000 WASAPI) > ODAC > O2 > Headphones

I chose 9 tracks, a mixture of audiophile reference grade tracks and music that I like. All the tracks used in my comparison are lossless FLAC. Most are 24bit 96KHz, some are 16bit 44.1KHz.

Comparison Tracks

Spanish Harlem - Rebecca Pidgeon (Female Vocals)

Alpha Dogs:

Vocals have a very natural and realistic tonality. Instrument separation is top notch, I can hear the instruments located in different areas of the room. Bass is full bodied and well textured. Instruments have a very realistic timbre with perfect decay timing.

HD600:

Bass is boomier and less controlled than the ADs. Mid-bass frequencies are more emphasized. Vocals have a more air and there is more treble emphasis. I can hear more of the breathing in vocals. All instruments have longer decay and are boomier. Soundstage is wider but instruments aren’t as well separated as the ADs.

K701:

Same soundstage width and instrument separation as the ADs. Less air than the HD600 but more air than the ADs. More treble emphasis than the HD600s. Overall sound is bit too bright which creates an unnatural tonality. Tambourine sounds too crispy and violins are too bright. Sound is a bit more tight and controlled than the HD600 but not as good as the ADs.

Winner: Alpha Dogs.

The HD600 and K701 may have wider soundstage and more air but the Alpha Dogs sound the most realistic and natural thanks to the more neutral sound and lack of resonances. The Alpha Dogs also have significantly better instrument separation.

Gadamaylin - I Ching (Ambience and Soundstage)

Alpha Dogs:

I can hear more ambient background sound and detail than the HD600 and K701. Bass is deep and well controlled. The erhu (traditional Chinese string instrument) has a realistic and full tonality. Better imaging, there is greater distance between close and distant sounds despite the more closed soundstage.

HD600:

Birds and low murmuring voices sound more distant than the ADs. Sounds more open than the ADs. The erhu has a more air and an enveloping sound which surrounds you. The bass sounds more boomy and less controlled than the ADs.

K701:

Soundstage is as big and open as the HD600 on this track. More controlled bass than the HD600s but not as controlled as the ADs. Too much treble emphasis which makes the percussion sound too harsh. Erhu has less air than the HD600, about the same as the ADs.

Winner: Alpha Dogs.

The Alpha Dogs technically sound the best with the better detail, imaging, and natural tonality. The HD600 is a close second, it may even be more enjoyable with the bigger soundstage. The K701 has too much treble emphasis which makes it too harsh to enjoy.

Hotel California - The Eagles (Rock)

Alpha Dogs:

HD600:

K701:

Winner: Alpha Dogs

Mozart Ave Verum - Choir of the Church of the Blessed Sacrament (Classical)

Alpha Dogs:

HD600:

K701:

Winner: HD600

Mozart Divertemento in D Mov 1 - The Manhattan Chamber Ensemble (Classical)

Alpha Dogs:

HD600:

K701:

Winner: HD600.

Money - Sam Yahel, Mike Moreno, Ari Hoenig, Seamus Blake (Jazz)

Alpha Dogs:

HD600:

K701:

Winner: Alpha Dogs

Best of My Love - Emi Fujita (Female Vocals)

Alpha Dogs:

HD600:

K701:

Winner: Alpha Dogs.

Suddenly - BT (Electronic)

Alpha Dogs:

HD600:

K701:

Winner: Alpha Dogs.

Get Lucky - Daft Punk (Electronic)

Alpha Dogs:

HD600:

K701:

Winner: Alpha Dogs

Win Counts

Alpha Dogs:

7

Comparison Overview

Comfort: HD600 > K701 > Alpha Dog

Soundstage and Openness: HD600 = K701 > Alpha Dog

Imaging and Instrument Separation: Alpha Dog > HD600 > K701

Air: HD600 > K701 > Alpha Dog

Treble quantity: K701 > HD600 > Alpha Dog

Treble quality: Alpha Dog > HD600 > K701

Mids quantity: Alpha Dog = HD600 > K701

Mids quality: Alpha Dog > HD600 > K701

Bass quantity: Alpha Dog > HD600 > K701

Bass quality: Alpha Dog > K701 > HD600

PRaT/Speed: Alpha Dog > K701 > HD600



Sound Overview

Alpha Dog Sound

Treble:

Mids:

Bass:

Soundstage:

HD600 Sound

Treble:

Mids:

Bass:

Soundstage:

K701 Sound

Treble:

Mids:

Bass:

Soundstage:

Conclusion

If you only listen to classical or have soundstage as a top priority, get the HD600. The better soundstage and air makes the HD600 a clear winner for chamber music. The HD600 is a great headphone to relax to with it's slightly warm and laid back sound.

If you listen to just about everything, want a fully closed headphone, don't mind a closed soundstage, and can afford it, get the Alpha Dogs

Additional Observations

Depth of Soundstage

Neutrality

Section 1: Low shelf, 84hz, -4.9dB, Q factor 0.70 Section 2: Analog bell, 3Khz, -3dB, Q factor 1.0 Section 3: Analog bell, 10Khz, +3dB, Q factor 1.0

Bass heavy?

Comfort

Drivability

Sony MA900 Comparison (Added on 2013/10/22)

MA900 has open soundstage, Alpha Dog does not. MA900 sounds darker (less treble emphasis). Alpha Dogs have more treble sparkle. Imaging is roughly the same. Mids sound very similar. Both the MA900 and Alpha Dog have realistic and neutral sounding mids with not much resonances. MA900 mid-bass is emphasized and the sub-bass is recessed in comparison to Alpha Dog. Alpha Dogs have deeper and more powerful bass. Alpha Dog has better speed and faster bass decay. MA900 bass is slower but a little faster than the HD600.

AKG K701, Sennheiser HD600 (painted black), MrSpeakers Alpha Dogs? Let's find out!Very natural and full sound. Fantastic dynamics and PRaT. Neither warm nor cold tonality, perfectly natural.Warmer tonality due to mid-bass emphasis. Bass isn't as tight and controlled. Guitars sound more airy and sparkly. Vocals have more air. Soundstage is more expansive and more open than ADs.Similar soundstage and openness to the HD600s. Bass is tigher and more controlled than the HD600. Cold tonality due to treble emphasis. Bass isn't as full bodied as the Alpha Dogs.. The Alpha Dogs may not sound as open as the HD600 and K701 but it more than makes up for it with the more natural sound and full bodied and controlled bass.Surprisingly large soundstage. I can feel the deep rumble of the organ, amazing bass extension and texture. Separation between different singers in the choir are clear. Vocals are very realistic and natural.Even bigger soundstage. Bass isn't as deep as Alpha Dogs but still fairly good. The choir sounds larger and more enveloping. I can hear more air and breathing sounds from the choir.Similar sound to the HD600 but with more treble emphasis and less air.. Due to the larger soundstage and air, the HD600s sound more realistic with this recording with the exception of the bass. The K701 also beats the Alpha Dogs for the same reason but lacks of the air of the HD600s.Good soundstage, I'm pretty satisfied with the soundstage with this song despite the ADs being closed but I don't expect it to be able to beat the HD600 and K701. Violins have a very natural tonality and good separation.HD600 is a clear winner here again. Soundstage is bigger and instrument separation is about the same as the ADs. The added mid-bass gives some with the lower frequency string instruments more body.Too much treble gives an unnatural tonality to instruments. Similar soundstage and instrument separation as the HD600s.The HD600s win again due to soundstage.Amazing low-level resolution. Percussion sounds incredibly detailed. Overall tonality is perfect and natural. The organ's mid-bass frequencies are very full bodied, controlled and well separated from the sub-bass kick. I love the bass with this headphone.Soundstage is more open than the Alpha Dogs. Bass is boomier. Cymbals are airier. Warm tonality. Not as detailed as Alpha Dogs. I can't hear the same low-level detail in the percussion. Lack of speed is partly to blame.Soundstage and detail is about the same as the HD600. Bass is tighter than the HD600s and detail is about the same as the HD600. Cymbals are crispier. Better speed than the HD600.. The Alpha Dogs neutral sound and superior detail makes it a clear winner despite the closed soundstage.Vocals and guitar are very natural and realistic. Fantastic imaging. Percussion in the background is well separated and sounds further away from the other instruments.Nice warm sound. Vocals have more air. Bass guitar is boomier. Percussion detail isn't as good as the Alpha Dogs, sounds a little muddier.The excessive treble emphasis of the K701 isn't so evident on this song. It sounds pretty natural but not as natural as the ADs. It also lacks the ADs detail. Bass is more controlled than the HD600 but not as good as the ADs.The Alpha Dogs win in technicalities (apart from soundstage). However, the HD600s do sound very enjoyable with this song with its open soundstage and air.Wow, the bass is AMAZING! The ADs pump out copious amounts of sub-bass rumble with this song. Like a sub-woofer strapped to my head (I know it's a cliche statement but it's true). The speed is top-notch, way better than the HD600 and K701. The synthesizers sound balanced and not too harsh thanks to the ADs neutrality.Soundstage is bigger, bass is boomier and not as deep as the ADs. The open sound is very enjoyable. Warm tonality doesn't suit this song.Soundstage is the same as the HD600 but lacks air. Bass is more controlled than the HD600 but not as controlled as the ADs. K701 sounds better than the HD600 for this song because of its cold tonality.Superior bass, speed, and neutrality makes the Alpha Dogs a winner for this song. I just wish I could have the HD600 and K701 soundstage on the AD.Neutral tonality sounds great with this song. Bass is deep, tight, and controlled.Bigger and more open soundstage, crispier treble, airier vocals. Bass is boomier and lacks control. Warmer tonalitySimilar to the HD600 but with tighter bass, less air, and more treble emphasis. Treble is too much and makes the sound too harsh.. Alpha Dogs win again due to neutral tonality and better bass (deeper, tighter and more controlled). ADs still lose on soundstage but the other superior sonic qualities make up for it.Neutral treble. Well extended but lacks air that the HD600 has. I think I need to EQ up 10KHz by 3dB to make it completely neutral.Neutral mids with a hint of 3KHz emphasis (3dB). Mids sound incredibly realistic and natural. One of the best mids I've heard on a headphone of any type.Fairly neutral bass. Sub-bass frequencies are emphasized by 5dB which could be a good thing since it compensates for the tactile impact that speakers have and headphones lack. Fantastic depth, extension, and control. One of the best bass I have ever heard on a fully closed headphone (only bested by the Sennheiser HD800 which is twice the price)Good soundstage for a closed headphone but I think it was stretch for Dan Clark to claim that it provides an open experience. It can't compete with the HD600 and K701 in the soundstage department.Airy and extended treble.Warm and seductive mids. Can be very enjoyable for vocal jazz music.Some mid-bass emphasis. Sub-bass has good extension but is somewhat slow and boomy. It's still fairly good and I can fully enjoy it if it wasn't for me switching back and forth between the Alpha Dogs.Good wide open soundstage as expected from a high quality open headphone.Too much treble emphasis. Makes most music sound too harsh.Fairly neutral mids, 3KHz region is emphasized by 4dB. I thoroughly enjoy the mids on the K701. It's very good but not quite as full sounding as the Alpha Dogs.Neutral bass with good extension. More tight and controlled than the HD600 but nowhere near as good as the Alpha Dogs.About the same as the HD600.. The Alpha Dogs are the best sounding closed headphone on the market. It's the most neutral headphone (along with the Etymotic ER4S) I've had the pleasure of owning (and I've owned a lot of headphones). The detail, speed and PRaT is fantastic.Not sure if I can recommend buying the K701 because it is too bright. I suppose it's alright if you don't mind EQing the treble down.Thanks for reading my review! Please feel free to criticize and provide constructive feedback.-------------------These are some additional observations that I have made after writing this review. Feel free to ask me further questions and I'll write the answers here.The HD600 and K701 beat the Alpha Dogs in depth. In high quality recordings with instruments placed at different distances from the microphone, the HD600 and K701 can render the depth more accurately (further sounds sound far and nearer sounds sound near). Unfortunately the Alpha Dogs don't sound as 3 dimensional and sort of mushes the depth together.This is very evident in the song "If I Could Sing Your Blues" by Sara K from The Ultimate Demonstration Disc by Chesky Records.From doing sine wave tests, this is my EQ to make the Alpha Dogs sound most neutral to my ears. It is very impressive that the Alpha Dogs need so little EQ to sound completely neutral. With other headphones I usually need to EQ a lot more to reach neutrality. The Alpha Dogs sound very neutral even without EQ. EQ brings it from 95% to 100% neutral, it is a subtle difference.I received lots of comments about my decision to lower the bass by 4.9dB in my EQ. The difference the EQ makes is actually smaller than it looks. The Alpha Dogs are only very slightly bass heavy. The EQ brings the Alpha Dogs more in line with the HD800 bass level (from memory). If you don't want to lower the bass that's cool. I don't use my EQ very often because I enjoy the slight bass emphasis.The Alpha Dogs are not as comfortable as the HD600 and K701. They are significantly heavier and have stronger gripping force. However, I can still wear them all day without too much discomfort.I attached this headband cushion to the leather straps which increased the comfort for me.The Alpha Dogs are easier to drive compared to other T50RP mods I owned (Paradox and Thunderpants). The O2/ODAC provides more power than I need. My less powerful Leckerton UHA-6S.MKII provides plenty of power and I would be happy with using it as my only amp for the Alpha Dogs. When using my Alpha Dogs portably, I don't even bother with an amp and drive it straight out of my Sansa Clip+ which drives the Alpha Dogs sufficiently (I listen on -24dB volume level in Rockbox).-------------------Here are the differences I hear between the Alpha Dog and MA900: