tbonner1
Headphoneus Supremus
- Joined
- Mar 13, 2002
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This is a review of the new M3 headphone amp by Rockhopper Audio.
I burned in the M3 with 8610 for 150 hours before serious listening.
Treble
Smoothness is a strength that Mosfets are known for. Tends toward the tubey without typical unbuffered opamp coldness. No spit or sizzle.
Midrange
Clean, full and lush tending toward a bit(and I do mean a bit) of warmth.
Bass
Solid and deep. Grips like a Krell amp with tight control. No wooly, loose or tubby-ness here.
Focus and Soundstage
Clear focus with instruments and voice delineated clearly and coherently from top to bottom. Soundstage is another strength of this amp.
Dynamics
Macro dynamics are good. Punchy. Good low level micro dynamics
M3 vs. Cmoy(s)
I have a standard CMOY and an “Enhanced” CMOY with OPA 134 and audiophile caps, which sounds very clean. I like the CMOY as you really hear the sound of the opamp with a minimum of other circuitry between the output and your headphone jack. I just like the idea of a minimalist design via straight wire with gain and love the concept of components such as passive preamps. However, the proof is always in the listening and the little CMOY falls short of the M3 in giving music harmonic undertones and proper decay. Can sound cold when compared to the M3.
M3 vs. Pimeta
The Pimeta with an 8610 should be a step up from the CMOY and sounds a bit warmer. Mine did not have the attack and definition of the enhanced CMOY and it seemed to be step sideways and not an improvement. Ho hum.
M3 vs. Melos SHA-1
The SHA-1 was considered by many (including Corey Greenberg and Stereophile in the early 90’s) to be one of the best sounding headphone amps. They sold for around $1000 new and today fetch over $400 used and cost at least that much to refurb through “restoration” sites. This Melos was smooth in the midrange and treble with good midrange texture and air around the voice and instruments. Bass on the Melos is not as deep and tight as the M3. This is where the M3 was simply more coherent. Dynamics were better on the M3. I did not hear a big improvement in soundstage of this SHA-1 over the M3, quite and achievement for the M3 as this has been a Melos strength over the years. I did hear a nice 3D soundstage through the Melos preamp output compared to my Aragon preamp but I did not hear a similar improvement in this area over the M3 via headphones. I wonder what the M3 would sound like with properly designed preamp outputs using the input ground?
M3 vs. PPA
The test PPA had the 8610 with Intersil 5002 buffers. As you would expect, of all the headphones amps tested the PPA sounded closest to the M3. The M3 had a smoother top end with more sheen around cymbals, superb treble definition, yet without sounding bright. I have heard MOSFET “haze” on amps from some time ago and was pleasantly surprised that this was not a problem on the M3. The PPA had more of a clinical sound. In the bass the M3 seemed to slew a bit more quickly than this PPA and sounded less congested during complex music passages. Decay was better on the M3. By comparison the PPA truncated trailing notes to a small extent. As good as the PPA is, it still lacked the smoothness of the M3. Attack was a bit sharper on the PPA. Bass and dynamics were better on the M3.
Conclusion
I have been chasing various headphones (and headphone amps) for 25 years. I have not been real happy with any of them when compared to the soundstage of speakers, but the M3 with Senn 5XX/6XX has caught my attention and brought me back to enjoying headphone listening. This amp is coherent and flat sounding from top to bottom. I am reluctant to submit such a good review of a new component as I realize I may be caught up in the “new is better” syndrome. But I CAN hear “the room” and soundstage with the M3/Senn combo on well recorded SACD’s. There is no hint of any Sennheiser “veil” with this amp; transients are good.
I would prefer to distill my notes, listen to more music and see if I am as enthusiastic after 6 months. However, I would rate my confidence in this evaluation as good. I would agree that in terms of design, the M3 is an evolutionary improvement over the PPA. In terms of sound, it is an incremental and audible improvement. The M3 was designed without compromises for portable use and it shows in particularly in the area of dynamic range.
I am not a big believer in voodoo or witchcraft, but I did think the unit sounded better after the 150-hour burn in particularly in the treble. My M3 also seemed sensitive to interconnect capacitance with the higher capacitance cables rolling off the high end and reducing transient response.
A word about the value of this amp. It is slightly simpler to build than a comparable PPA and I have seen assembled prices that are less expensive making the M3 a deal for those on a budget.
Thanks to Morsel and Amb for a mature design and alpha/beta testing procedures that reminded me of the New Product Introduction Process from the days I worked at a mini computer manufacturer near Boston. Thanks to Stephen of Rockhopper Audio for a professional build and a great buying experience.
Test system hardware
JM Labs 820 Cobalt speakers
Cayin TA-30/Prima Luna Prologue One Integrated Tube amp
Aragon 2004 Mk2 amp
Aragon 24K SP preamp
Rotel 991 CD and HDCD player (love HDCD)
Sony 333ES SACD player
Technics DVD A10 DVD-A player
Monster 2.4 speaker cable
Home Depot HD 14 and 16 speaker cable (not bad, read Audio Cable Asylum)
Silver Audio 4.0 interconnects
Headphones
Stax SRX/SRD-7
Koss ESP-950
Senn 497
Senn 580
Senn 650
Koss KSC 35
Koss Porta Pro
Koss Porta Pro 2
Grado 80
Grado 225
Sony mdr V6
Sony mdr 780
I burned in the M3 with 8610 for 150 hours before serious listening.
Treble
Smoothness is a strength that Mosfets are known for. Tends toward the tubey without typical unbuffered opamp coldness. No spit or sizzle.
Midrange
Clean, full and lush tending toward a bit(and I do mean a bit) of warmth.
Bass
Solid and deep. Grips like a Krell amp with tight control. No wooly, loose or tubby-ness here.
Focus and Soundstage
Clear focus with instruments and voice delineated clearly and coherently from top to bottom. Soundstage is another strength of this amp.
Dynamics
Macro dynamics are good. Punchy. Good low level micro dynamics
M3 vs. Cmoy(s)
I have a standard CMOY and an “Enhanced” CMOY with OPA 134 and audiophile caps, which sounds very clean. I like the CMOY as you really hear the sound of the opamp with a minimum of other circuitry between the output and your headphone jack. I just like the idea of a minimalist design via straight wire with gain and love the concept of components such as passive preamps. However, the proof is always in the listening and the little CMOY falls short of the M3 in giving music harmonic undertones and proper decay. Can sound cold when compared to the M3.
M3 vs. Pimeta
The Pimeta with an 8610 should be a step up from the CMOY and sounds a bit warmer. Mine did not have the attack and definition of the enhanced CMOY and it seemed to be step sideways and not an improvement. Ho hum.
M3 vs. Melos SHA-1
The SHA-1 was considered by many (including Corey Greenberg and Stereophile in the early 90’s) to be one of the best sounding headphone amps. They sold for around $1000 new and today fetch over $400 used and cost at least that much to refurb through “restoration” sites. This Melos was smooth in the midrange and treble with good midrange texture and air around the voice and instruments. Bass on the Melos is not as deep and tight as the M3. This is where the M3 was simply more coherent. Dynamics were better on the M3. I did not hear a big improvement in soundstage of this SHA-1 over the M3, quite and achievement for the M3 as this has been a Melos strength over the years. I did hear a nice 3D soundstage through the Melos preamp output compared to my Aragon preamp but I did not hear a similar improvement in this area over the M3 via headphones. I wonder what the M3 would sound like with properly designed preamp outputs using the input ground?
M3 vs. PPA
The test PPA had the 8610 with Intersil 5002 buffers. As you would expect, of all the headphones amps tested the PPA sounded closest to the M3. The M3 had a smoother top end with more sheen around cymbals, superb treble definition, yet without sounding bright. I have heard MOSFET “haze” on amps from some time ago and was pleasantly surprised that this was not a problem on the M3. The PPA had more of a clinical sound. In the bass the M3 seemed to slew a bit more quickly than this PPA and sounded less congested during complex music passages. Decay was better on the M3. By comparison the PPA truncated trailing notes to a small extent. As good as the PPA is, it still lacked the smoothness of the M3. Attack was a bit sharper on the PPA. Bass and dynamics were better on the M3.
Conclusion
I have been chasing various headphones (and headphone amps) for 25 years. I have not been real happy with any of them when compared to the soundstage of speakers, but the M3 with Senn 5XX/6XX has caught my attention and brought me back to enjoying headphone listening. This amp is coherent and flat sounding from top to bottom. I am reluctant to submit such a good review of a new component as I realize I may be caught up in the “new is better” syndrome. But I CAN hear “the room” and soundstage with the M3/Senn combo on well recorded SACD’s. There is no hint of any Sennheiser “veil” with this amp; transients are good.
I would prefer to distill my notes, listen to more music and see if I am as enthusiastic after 6 months. However, I would rate my confidence in this evaluation as good. I would agree that in terms of design, the M3 is an evolutionary improvement over the PPA. In terms of sound, it is an incremental and audible improvement. The M3 was designed without compromises for portable use and it shows in particularly in the area of dynamic range.
I am not a big believer in voodoo or witchcraft, but I did think the unit sounded better after the 150-hour burn in particularly in the treble. My M3 also seemed sensitive to interconnect capacitance with the higher capacitance cables rolling off the high end and reducing transient response.
A word about the value of this amp. It is slightly simpler to build than a comparable PPA and I have seen assembled prices that are less expensive making the M3 a deal for those on a budget.
Thanks to Morsel and Amb for a mature design and alpha/beta testing procedures that reminded me of the New Product Introduction Process from the days I worked at a mini computer manufacturer near Boston. Thanks to Stephen of Rockhopper Audio for a professional build and a great buying experience.
Test system hardware
JM Labs 820 Cobalt speakers
Cayin TA-30/Prima Luna Prologue One Integrated Tube amp
Aragon 2004 Mk2 amp
Aragon 24K SP preamp
Rotel 991 CD and HDCD player (love HDCD)
Sony 333ES SACD player
Technics DVD A10 DVD-A player
Monster 2.4 speaker cable
Home Depot HD 14 and 16 speaker cable (not bad, read Audio Cable Asylum)
Silver Audio 4.0 interconnects
Headphones
Stax SRX/SRD-7
Koss ESP-950
Senn 497
Senn 580
Senn 650
Koss KSC 35
Koss Porta Pro
Koss Porta Pro 2
Grado 80
Grado 225
Sony mdr V6
Sony mdr 780
