Original Electronics Master Phones Amplifier: Cannon-blast from the Past

DISCLAIMER: this is more an entertainment piece since, while I see one of these currently on sale on eBay for $150, they're pretty scarce overall and I don't think they're necessarily worth looking to try unless you're looking for something very specific. Got this amp in on loan for a few months but I actually only spent maybe four days listening to it-- it was just sitting collecting dust for 99% of the time I had it which is probably a spoiler. These impressions are actually from July last year but I'm just now bothering to draft a proper review.

Recent conversations about how modern gear is almost always going to be inferior to known vintage gear may or may not have convinced me to do this. Ahem.

And yes, that really is what the amplifier is called.

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EXECUTIVE SUMMARY: Eerily clean background like music is playing on the deepest level of Nordic Hel, only the headstage is so far forward that things sound like they're playing in your nasal cavity (good width though). The amp slams like a sledgehammer which is impressive considering I have an AKM Modi 3+ feeding it; the treble is horrifically brash and incisive, and there's overall slightly less detail retrieval relative to the Cavalli Liquid Carbon. The amp doesn't sound overly smoothened but doesn't have very high engagement factor either.

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SOURCE: Schiit Modi 3+
TRANSDUCERS: Sennheiser HD600, Klipsch Heritage HP-3, Campfire Audio Solaris, Etymotic ER2XR
OTHER AMPS REFERENCED: Massdrop X Cavalli Tube Hybrid (stock power supply), Schiit Magni 3+, Schiit X Nitsch Magni Piety, Lake People G109A

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There's this popular misconception that older is better precisely by virtue of their being older. In some regards that holds true as in the case of aged whiskeys, vintage sewing machines, some reconditioned fountain pens from the 70s and 80s, the Shure SM57 still being around while essentially unchanged for nearly 60 years, and many Sennheiser cans still finding a place in many people's homes to this day-- I hear great things about the HD250 Linear and am curious to get ears on a pair, but more pertinently I have a pair of HD600s I got off a good friend that, as far as my preferences and tastes go, many modern headphones below the Focal Utopia do not categorically and irrefutably surpass.

Despite these many cases lending credence to that aphorism (or is it more of an adage?) "they don't make 'em like they used to", to call it a universal truth is dog doodoo.

Besides anime soundtracks, pop-punk, and the occasional stomp-dance electronica e.g. Daniel Deluxe or Timecop 1983, a lot of my taste in music was informed by growing up around my grandparents and those old Tom & Jerry cartoons; while I would be lying through my braces to profess myself any sort of authority on orchestral works or jazz virtuosity, these are genres that speak to something within that's more primal and bare-skinned. The same goes for Billy Joel's Glass Houses era, Katrina & The Waves's eponymous album, or Debbie Gibson's Electric Youth.

Growing up the way I did, I bought into the notion that, while modern music could still be fun and involved, they genuinely didn't make em like they used to. Older music was just overall better compared to how hit-and-miss modern cuts can be (anyone else remember Milli Vanilli?)

Thing is, that really isn't a fair comparison to make, not even for anyone who actually was around at the time.

I could pretend to know a lot about tracks from before I was born, but besides being dishonest I wouldn't even know how to begin to fake that sort of knowledge. It's not as simple as Googling "What were the worst musical acts from 40 years ago?" because the sort of bad I have in mind isn't the "bad but memorable" kind like Escape (The Piña Colada Song), but the kind that was so insipid that few, if any, historical records bear witness to their name. It's precisely that dearth of information that skews public perception because, nostalgia notwithstanding, the only songs people really remember from that era are the ones that still get airplay today, the ones with actual staying power.

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This was released for about $200 back in 2006 and seems to have flown under most people's radars just going off what information I can find on the internet. As I mentioned up at the start of this post these do still seem to be circulating, but they're uncommon.

I made a status update in the middle of last year talking about how I found this amp "uncanny" sounding, and I find that I still agree with that preliminary evaluation. The amplifier has what I can only describe as a lifeless void for a blackground and, while I definitely lack the same degree of knowledge regarding amplifier design or the volume of experience with assorted builds that many on here can readily boast, I still think it's borderline scary how utterly dark and pristine the background on this amplifier is, as if music were playing in the belly of some Yog-Sothothian mindless void. Not to say that the amplifier is completely smoothed over without nuance, though: while not necessarily as resolving as either the Magni 3+ or the Massdrop x Cavalli Tube Hybrid (stock tube and power supply), it manages to not sound like it's buffing detail away with steel wool.

There's a profound sense of disquiet that comes from hearing music getting shoved into your face from out of what sounds like what a Vantablack-coated chamber would look.

I genuinely don't know how to categorise its resolving ability other than "it's fine". Having said that, it doesn't have much in the way of what I perceive as plankton, or what I affectionately call "that sense of dread when you mean to listen to just one song to check something but end up staying awake until 3AM because the Magni Piety makes it really, really hard to press pause, let alone leave your desk". Still, it's far from boring or actively disengaging. It's worse than the Magni 3+ in terms of exhibiting trailing decays and room cues, but it's at least better than the G109A which can often sound overly sterile and smoothened.

The Lake People G109A (impressions here) is an amplifier that is fully competent, if pricey for what you get out of it. I guess I could see this as being competitive with the Master Phones amp in terms of gross detail retrieval, though something like the Magni 3+ handily outperforms either in terms of plucked string woobliness (this is a good kind of wooblement). The MCTH whoops both the G109A and the Master Phones for microdynamic nuance, but that's a particular strength of the amplifier so comes as no surprise. The MCTH has a less definitive lead over the recent Magnis here, IMO, and the 3+ and Piety both take the lead for gross detail.

The headstage is vaguely reminiscent of how I heard that of the Beyerdynamic DT880 Premium (250 ohm), my main headphones for a few years a while back. There's hardly any depth to the headstage (I'd go so far as to call it negative headstage because of how far into my nasal cavity sonic elements seem to manifest sometimes [see: Disturbed - Down with the Sickness]) but the width is actually pretty expansive. Some people might prefer this sort of presentation, and I do feel that I might have fallen into this category a few years back, but in recent years I've found that I don't value headstage size so much as I do depth layering and lateral imaging precision. The nod goes to the MCTH for having the headstage most in line with my preferences, I guess, though again it does fall behind in other respects.

On that note, there's not really much in the way of a "center" on this amp as far as imaging goes. Rather than being three-blob as the G109A can be, it's just two blobs on either side of your head. The amp has comparable headstage width to the Magni 3+, but the baby Schiit amp does a significantly better job showing off contrasts of depth in recordings than the ostensible Master.

So far, other than the blackground, the way I've described this amplifier makes it come off as a middling-leaning-mediocre amplifier that may well have been truly forgettable. I'm going to remedy that: the macrodynamics and voicing are so extreme on this unit that it is anything BUT innocuous.

I first tried this with the Klipsch Heritage HP-3 since they were my daily driver headphones prior to selling them off back in August 2022 (immediately kinda regret that but eh), but the gain on the amp was so high that I couldn't use them without engaging a LOT of digital attenuation. Since I figured that that wasn't particularly fair to the amplifier, I had the Klipsches tag the Sennheiser HD600s in and I immediately noticed a few things:

• the gain on the amp was indeed stupid high
• there are DEFINITE problem spots in the treble region that made the HD600s unusably sharp with a lot of material
• HOLY CRAP THEY MAKE THE SENNHEISERS SLAM REALLY f'ing HARD
• oh right the volume knob was missing, forgot that the owner mentioned that. not as easy to operate.

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I'm playing my reaction up a bit for fun, but I was genuinely shocked and very nearly offended when I put on Peter Bjorn & John's Young Folks; the percussion at the beginning of the song made me feel like I was about to get a con-cussion. When I tried putting on Daniel Deluxe's Infiltrator off the Ghost Runner soundtrack with the Klipsch HP-3s (again: with a f**k ton of attenuation) it genuinely felt like I was getting an infrasonic ear cleaning with how much earwax was getting shaken out (figuratively speaking of course).

Going back to my disclaimer that I've not heard very many amps that SBAF uses as a touchstone, I've not had the opportunity to try the legendary Schiit Mjolnir 2 out and have actually been wanting to demo one for the longest time. That said, it's hard to believe that the HD600s could be convinced to hit any harder than they do when paired with this amp; forget some skinny guy putting their whole body weight into a single punch, this is the Mountain from Game of Thrones picking said skinny dude up and using them as a blunt weapon. I do think the MCTH is competent at macrodynamics, but it's not necessarily an area of strength for the amp; the Magni 3+ and Piety don't come anywhere close to slamming as hard as the Master Phones amp, though the both are perfectly respectable.

Heck, even comparing the macrodynamic slam I got with the Senns out of what the friggin Eddie Current Studio Jr. (300B) managed with its balanced output, the Master Phones amp came out ahead. It's not worth talking about how well each amp managed to grip the HD600's drivers by the family jewels because the Studio Jr was so far ahead in this regard that it's effectively a non-compete, but going purely by how vicious the presentation can be the Master Phones takes a decisive lead.

"Vicious" is also a good way to characterise the treble on this thing; going back to the Peter Bjorn and John track referenced above, I actually mainly use that as a treble stress test, and it's one that the Magni 3+ fails for me (the Magni Piety, incidentally and on the other hand, passes it handily); the Master Phones amp flunks with flying colours thanks to an excess of mid-treble sizzle, as it does on anything with even remotely present hi-hats or vocal sibilants (see: Elysian Fields - Sugarplum Arches, Asian Kung-Fu Generation - Rewrite, and Disturbed - Stricken). The tizz on the amp seems fairly high-Q, but it sounds like it's at a personal pain spot for me because while the owner doesn't seem overly bothered by it, I immediately take headphones off when that region's activated.

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Extension on either extreme is somewhat lacking. It sounds like both the Magni 3+ and the G109A outdo the Master Phones in sub-bass rumble, no contest, though the Master Phones manages to outclass the Lake People amp for bass texture; much like the Magni 3+ the Master Phones amp actually has good bass-to-mids transition, keeping the bottom end from overwhelming the middle frequencies. It's a fair lot leaner sounding than either the Magni 3+ or the MCTH, though not to the point that it sounds anaemic. Conversely the G109A has a pronounced boxiness to vocals that never really goes away, though keeping it on for longer stretches ameliorates the problem somewhat. Air frequencies are present, moreso than on the G109A at least, but they seem buried relative to the bass and the midtreble prominences.

There's a lot of midrange glare to complement the treble prominences on this amp. I almost never have a problem with Florence + the Machine's Cosmic Love, and that's a track I often play on assorted gear, but with the Master Phones amp Florence Welch's belting got to be unbearably grating at moderate volumes. This is probably going to be less of a bother than the upper midrange emphasis that the Magni 3+ can exhibit on... a lot of things, but that's where preferences come into play. The MCTH does sometimes manifest a bit of glare to the like of female vocals as well that can be grating (see: Dave's True Story - Still I Adore You or Macross Delta's Walkure - Hametsu no Junjou ). The upper midrange on the Master Phones amp is laid back by comparison, so makes distorted electric guitar sound less harsh.

I'd call the midrange on this amp clean, and not in a derisive way, because of how on some material the added emphasis to the vocal harmonic range actually helps some voices cut through a mix, though it can make a lot of less laid-back instrumentation cut a whit too deeply as in the woodwinds on Sinatra's In the Wee Small Hours (the beginning of Mood Indigo makes me wince a bit).

Speaking of glare, the OI of the amp is likely fairly high because it seemed to turn the Campfire Solaris into a super-Etymotic. I remember only listening to a few songs with the Solaris because I didn't want to push my luck with them again, but running measurements, it was interesting to see what the Master Phones amp did to the FR.

GREEN trace: Schiit Magni 3+ (0.9 ohms)
RED trace: Original Electronics Master Phones Amplifier (???? ohms)

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The amplifier is split into a surprisingly light typical hardbound-book-sized main chassis and a separate power supply that's so heavy it could probably crack concrete floors when dropped. This apparently holds a fairly decent toroidal transformer which may explain the endless void that is the blackground as well as the firmament-shattering slam it seems to give dynamic headphones.

This amp might be worth tracking down if you want slam for days, don't mind significant prominences in the middle midrange and wholesale treble area, don't care about headstage at all, and don't want to spend a lot of money, but there are a lot of cheaper amplifiers out nowadays that out-resolve it, are more well-rounded, and take up a lot less space. Still, it's far from a perfect thing, and while its strong points are worth admiring I don't think that it's doing anyone a service to avoid pointing out the shortcomings that it does have.

Pic alongside an Altoids tin for size reference that, if it were stuffed with CMOY internals, would be very much period-appropriate for this amp:

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Official SBAF Eloquent Equitable Empathizer, you’ve convinced an amp agnostic to reconsider the importance of amp sound quality and synergy. I seek what you describe as slam. Based on your post a larger torroidal transformer tends to provide this character. For a mid-fi budget Id guess Id be looking at mostly speaker amps (for HE6se). The quest begins.

Pretty cool demonstration of how an output impedance mismatch (if I understood correctly) can alter HD600 measured frequency response.

 

Cons of having a wall of text: easy to overlook things The IEMs used to showcase impedance mismatch were the Campfire Solaris! I don't have much in the way of listening impressions with them cuz the voicing was offensive to me, and I didn't want to push my luck with the golden bananas haha.

I WISH the HD600 bass extended that far down!

Being amp agnostic on this forum? Talk about rare lmao. Really though after this little refresher I'm convinced that there's a lot more excellent stuff for much less money now than just a decade ago, and moreso than back in 2006 (never heard this amp before but it was released just as I was starting to take an interest in "nicer" audio as a kid).

I wouldn't recommend getting this one cuz of the offensive voicing, but that's just me covering my butt. There's that one on eBay I saw yesterday (it's in Ukraine, oof), but eBay is risky etc etc

 

Your writing style is what I enjoy, the context not so much. jk. I goofed and didnt look so carefully, thanks for correcting me.

I know there are differences. But Ive only heard midfi and lower amps so the small differences in sound to me are not worth the expense. However after reading your post I will try to navigate towards a slammy amp (for planar) as that might be worthwhile if not too expensive like possibly a used speaker amp.

I definitely heard that in your review. Not getting that amp.

 

To estimate the Master's output impedance, I ran some calculations on the impedance vs frequency profile of the Solaris to see if I could replicate the frequency response differences you measured.



Because the predicted differences become smaller with increasing Z it's hard to be much more definitive than saying it's probably more than around 30 Ohms, but what you saw is not inconsistent with the amp having the notorious 1996 IEC 61938 'standard' 120 Ohms.

If so, low damping might account for the slammin' you heard (which likely brings with it higher distortion, see right at the bottom here).

 

Just going purely off subjective experiences to date, there being hardly any damping factor does seem like it would track with the concussive force I was getting out of the HD600s and the harshness I was getting scattered throughout the frequency spectrum. Great call!

I'm ignorant with regard to amp design so while excesses of distortion likely orders of magnitude higher than what you'd get on the average budget amp nowadays makes sense, I wonder at what could be behind the impressive blackground. I wasn't kidding when I said that it sounded scarily pristine, moreso than any other amp I've heard to date (which isn't a lot, granted, but damn).

 

Focal Clears are crying out for this amp. Play Daft Punk and feel the drivers meeting in the middle of your head

 

The owner has Clears-- verbatim: "i can feel it in my lungs," HAH!