Ray Samuels Apache Limited Revision 4 (UPDATED 1/10/21)

This is my first "proper" review on Head-Fi. I'd be remiss if I didn't post one, though, as the Ray Samuels Audio ("RSA" from here) Apache is a relatively rare amp, and has limited coverage online. As a new owner, I feel pretty strongly that it deserves further praise and information posted about it, in case Ray ever gets enough parts to start taking further orders!

First, I should note that my rating of 4.5/5 is simply to leave room for the mega-buck amps in the price class above $ 3,000 USD, and I would presume those can achieve more on a larger budget. That said, within my experience, the Apache safely earns a 5/5. I certainly can't imagine ever wanting more in an amp.

Second, some additional context: This is my first high-end solid-state amp, though I have some experience with "mid-fi" solid-state amps, having owned the Burson HA-160, SPL Auditor, and the Violectric V200. I've also owned the entry-level Creek OBH-11, which got me initially hooked on head-fi, with the Burson acting as the springboard into what I consider "proper" headphone amps a couple of years later.

I also own the Woo Audio WA2, which now has been equipped with top-notch tubes and is my end-game tube amplification for years to come. However, for shorter listening sessions, I felt a strong need to invest in a solid-state amp to match. The prospect of causing added wear and tear on my tubes when powering up the WA2 and shutting it down again after a short listen made me hesitant enjoy music as often. And we can't have that!

As a result, I started hunting for a solid-state amp that would serve a proper foil for the tube-based WA2: It needed to be quiet with low power consumption, should act as a high-quality preamp for my stereo setup, have precise volume control, and have several sound signature traits that mimic an OTL tube amp. Oh, and it needed to play nicely with high-impedance headphones as I own two ZMFs (the Eikon and Verite Closed) and plan to purchase my final (?) ZMF pair in a few months (the Atrium Closed). Not a tall order at all, right?

Using a budget of $ 2,000 USD as my ceiling and shopping among new and pre-owned units, I initially (among others) had the Pass Labs HPA-1, Kinki THR-1, and Violectric's new 2-- series in mind, while their mid-range amps generally either were too expensive or were described by owners as more neutral in tone. However, I also came across very favorable reviews of Ray Samuels Audio amps, including strong statements that they were excellent-sounding with ZMF headphones. Testimonials supporting this included Zach Mehrbach's own notes, which weighed into my purchase decision.

After considering the RSA HR-2, I stumbled over an RSA Apache in the Head-fi classifieds that turned out to be available. I was also fortunate enough to buy it from an exceptional community member who shares my Norwegian roots (@cinisi ), and we had many pleasant exchanges via PM in addition to a smooth transaction.

As the Apache unit was 230 Volts, I needed to get it switched to 120 Volts for my use, and thanks to great advice by the esteemed @John Massaria , I had cinisi ship from Europe to Ray Samuels directly after letting Ray know it was coming.

Ray is both a gentleman and a scholar, as they say. He only charges a nominal fee for op-amp upgrades, something I requested as he has continued to improve the Apache topology with newer, more sophisticated and high-quality op-amps that fit his design. He overhauled the amp and power supply as well, restoring the Apache to as close to as-new state as possible. I cannot speak highly enough of Ray's customer service!

I received the amp yesterday, and due to Ray's burn-in and testing before shipping it to me it sounded excellent out of the box. However, I needed more time today to try it out with a range of music and to listen more critically.

I have connected it to my Schiit Audio Gungnir Multi-bit via balanced Harmonic Technology Pro-Silway interconnects, and used the supplied high-quality vibration-mitigating spikes and additional protection discs (after all, who wants to mar the gorgeous black case finishes?).

Listening notes with my pair of ZMF Eikons (Bocote LTD, Norne Einvaldi Reference cables):

• Great horizontal soundstage. It extends well beyond the cans, which is unusual with the Eikon unless it’s driven by an excellent amp.
• The bass sounds like it emanates from space. The bass depth and clarity puts good tubes on my WA2 to shame, and I don’t say that lightly. The Apache has phenomenal bass control- with stops/starts happening on a dime, so to speak. This is visceral bass with a headphone that has full range like the Eikon.
• The Apache is FUN FUN FUN to listen to! The music grabs you by the lapels and drags you into the music. You want polite background music? Get another amp.
• The Apache is dead silent- this helps contribute to micro detail and the overall feeling of space.
• When listening, it's hard to not nod along or tap your feet with the rhythm- a true sign of great PRaT.

Track samples from my listening:

• H.E.R.: “We Made It”:
  • This track is a great test of bass depth and quality. Bass as diffuse pulses, speedy beats, or waves spreading outward- the Apache does it all without the bass getting overcooked or bloated. This amp controls the biocellulose driver of the Eikon magnificently! In addition, the bass does not spread into midrange.
  • The Apache also does not get harsh in the treble despite the song's slightly hot mix with somewhat overemphasized highs.
• Elbow- "One Day Like This":
  • This track showcases a delicate piano portion, which the Apache renders with grace and clarity.
  • Singer Guy Garvey floats steadily in center of stage, rock solid without wavering.
  • The track then introduces a bassline that thrums underneath without interfering with the rest of the song.
  • Later in the track, you can hear the bows moving across the massed strings, and plucked strings resonate with body.
• Arctic Monkeys- "Arabella":
  • For a fairly gritty rock track, this track has bass that is incredibly detailed and tuneful, and the Apache shows off its chops with relish. The bass drum has punch and you can hear the drum's skin resonate with capital "R".
  • The drum kit's high hat is clear, and you can hear the trailing ring shimmer in the air.
  • In the midrange, it is very clear when the mix uses deliberate distortion on the lead singer's vocals.
• Royal Blood- "Typhoons":
  • I am hearing more details in this track's mix than ever, including detailed ringing of metal in the opening's percussion.
  • As I noted when listening, this is a "Great amp for rock"!
• William Fitzsimmons- "Good Morning (Pink Ganter Remix)":
  • This is a song that has great channel separation, and the low noise floor and dual-mono topology of the Apache represents this exceptionally well.
  • Fitzsimmons' trademark breathy voice is well rendered, really bringing him to life.
  • I can REALLY hear into the mix, which has a lot of great details that are showcased without being overwhelming.
  • Stereo pans are CRYSTAL clear
• Death Cab For Cutie- "Doors Unlocked and Open":
  • This song proves the Apache's capability to propel driving rhythms forward with gusto!
  • Ben Gibbard's distorted voice is detailed, but not harsh to listen to.
  • I am now hearing more extended echo/reverb detail than ever before on other amps, which is impressive.
  • Great horizontal sound stage is also really noticeable.

At this point I simply stopped taking notes- it was too fun to listen!

I can only tip my proverbial hat to Ray Samuels for building an incredible amp that I will treasure for many, many years to come. The Apache is a perfect counterpoint to my Woo Audio WA2, and I will not miss its charms when I use the solid-state part of my system- which is exactly what I hoped for.

The Apache has delivered that in spades, and if I someday have to downsize to a single amp, the Apache is likely to be "the last amp standing". It is that charming, keeping enough of the beauty of tubes while injecting the dynamics and detail of solid-state, literally without missing a beat. To say I'm pleased with my purchase would be a severe understatement, and if you get the chance to buy an Apache whether in pre-owned or new state, I'd wager it will hold its own against amps at a higher price point as well.

[Minor edits made August 16, 2023 to clean up formatting and a few typos]

When thinking about the term classic - what comes to mind? How does something become a classic? Is it the lines, the functionality, the rareness? The performance? How do they exist in our world, even from the day of conception to manufacture- some people know or try and guess what car, what watch, what piece of furniture, what wine will be an invariable icon for decades to come. Some people preclude or guess what will be ordinary and what will separate to the extraordinary based on merits of all factors included - usually; performance, the nature of true rarity, attention to detail and of course desirability.


With audio equipment- there are designers who will go down in history for breaking the mold, perfecting the mold, breaking new ground and just plain creating state of the art designs that will be challenged but not bettered. Few things in audio are long lasting and highly desirable years after release- I can count a few. Think: Nakamichi Dragon Series by Niro Nakamichi, PASS Amplifiers designed by Nelson Pass, Mark Levinson designed by Mark Levinson himself, Krell amps by Dan D'Agostino. The remarkable crafted Kennerton headphones by Valentin Kazanzhi. The stratospheric creations like Audio Note Japan Ongaku series by Hiroyasu Kondo, or Lloyd Walker who went to the ends of the earth for perfecting the turntable. These designers and products we get to have grace our homes for the exchange of some cash is quiet incredible. If you are lucky enough to afford such designs - you actually have a useful functioning piece of audio memorabilia that exemplifies the state of the art for a period that transcends time. The Dragon Cassette deck is and will always be one of the best performing decks ever- no mater the time or place in the future. Same thing with Walker turntables- there will be few if any future designs to challenge his designs and flawless performance. Thus the term state of the art. Iconic for generations and highly desirable for anyone who truly knows what they are looking at or listening to. Enter Ray Samuels. I will not go into length on who Ray is but only to talk about his iconic state of the art highly desirable amplifiers. The myth the legend- the man who is known for extraordinary service and CARE! I can personally attest being a customer and acutely aware of his unbelievable care. Care in talking and dealing with customers matched by the perfection of a truly state of the art product. Beholding the units in person- you know you are in the presence of greatness- engineering that satisfy both the need for beauty and performance- his designs are beautiful to behold inside and out. Do not take my word for it- just look for yourself:

But looks alone are no reason to call a designers products iconic if it lacks in performance. It needs to exemplify the essence of what most people look for in buying audio- to sound nearly if not clearly the best of the best in the product segment. To set new standards. To break ground or surpass the ones before it and after it.... I believe the top performing, top tear products by Ray Samuels does just that, and here we are focusing like a laser pointer on The Apache.

For those who think Ray is retired- in a way he is, he may not go to the headphone shows anymore and may only have very limited amounts of inventory but he still assures me and others his products are still being serviced when need be and sometimes perfected and offered to those who seek them out. My Apache is an example of how Ray is still creating and perfecting his own product. Originally created and release in 2007, The Apache is an all solid state, truly dual-monaural design from end to end headphone amp and full functioning pre-amp that Ray just updated to Revision 4 using state of the art chips, resistors and caps for me in 2020. Before shipping out any units- Ray burns your gear in and listens to it before he ships it. WHO in the world then and now still does that? Ray is a designer who truly cares- after all... his own name is on each product. It is so clear to me Ray is one who pays attention to the art of creating, updating and maintaining his equipment so that they perform at their best. Think about it- putting your own name on a product says a lot of who you are- same thing goes for editors or reviewers I think. When a reviewer uses his own name like myself- I hide nothing and hope people get it- that by using my real name it is an expression of my sincerity to what I write and how accessible I am for critiques and comments and improvements. I suspect Ray is no different.





If an amp is suppose to just amplify and inject no sound of it's own - ok... lets talk about it. That is the goal right? Or is it? Lets talk water and bringing it down to zero ppm... If you want water filtered by ZERO Water filter company it filters out all the impurities down to 0 parts per million (PPM) and tastes like nothing really. I used Zero water filters for a few years and I always felt like maybe its lacking... lacking what? I don't know, thirst quenching effects of just carbon based water filters like the ones offered by Pure or Brita? Our water where I live on Long Island is among the best out the tap (54ppm to begin with which is very low for contaminants). So filtering it down to Zero ppm makes the water as pure as anything or is it? Is it lacking nutrients if there is such a thing in water? You know minerals naturally occurring in water that probably should be in there to begin with but was washed out with the Zero filter water system. Same with music, who wants a DEAD neutral lacking in spaciousness amplifier? I recently did an article on cables (LINK) where I compare cables to light and frequency of light which is based on Kelvin. The Sun is a natural barometer of what light should ideally be- but sometimes, I maybe not you... but I want it a little more warm than the natural sun. I wrote: "Before we get started - What does reality and things like human faces look like under different light colors in the range of kelvin? Me personally I like people and my music to be around 4000K to 4500K- a little warmer than dead neutral or natural. I like my light bulbs around my house to resemble the actual sun temperature of kelvin which again is between 4500-4900K. Some rooms look best in more blue light like a hallway or bathroom and some rooms like the bedroom look better in a warmer light. But no place looks good under blue light over 6K in my opinion." Are they accurate to reality? well sort of. Based on what frequency tendency? Should Sun light be the reference... some amps sound cooler and some warmer- ok- lets go from there...

If measured performance was that simple in stereo equipment we should all buy an amp that has the lowest total harmonic distortion (THD) and highest slew rates and best dynamic range while honoring the human hearing levels of 20khz-20hz signals and perhaps beyond that of human hearing for some. Go buy a top rated SINAD rating like the Tom Christiansen Audio HPA-1 (no Opas to switch in and out- the TCA uses a non removable TI LM4562 which has already been updated/rebranded to a Texas Instruments LME49720. I should mention both have a reputation of being a bit glaring in sound- not my words but directly from the people who have actually used it claim) The TCA HPA-1 is modeled similarly to the DYNALO Class A kit amps and very similar to my WHAMMY and many other amps. If looking for specs alone you could go much cheaper than that ... Go buy a Topping A90. They all measure extremely well... but really how well do they engage the listener after listening. I know and let me share.. I did just that, I bought the Topping A90... and I returned it after 26 days. I did extensive listening and comparing to my PASS WHAMMY (w/Dual Opa627's installed). The Topping A90 which by all respects is one of the best measuring amps of our time- especially when it comes to price. Stop here go buy one- or maybe return one after like I did... and keep searching as I did... it should have bested anything in it's path- did you listen to other reviewers who said it's nearly as good as the Benchmark HPA4 amp? Nonsensical hyperbole. In Russia (I'm Italian but my wife is Russian) there is a saying, "Вы не получите ничего для вас", or in English- "You won’t get any, there’s none for you." Another is "ты получаешь то, за что платишь" or in English - "you get what you pay for." My wife also said that's rude and do not print that- but hey here we are.... Sorry but most of the time it's true. We all want to buy the best of the best for dirt cheap. Yes the A90 is very good for the money but it will never be an iconic piece of gear that is handed down from generation to generation with a highly desirable factor attached to it. It's a fine amp, offering plenty of features for the price no doubt. Don't get upset when I say its not an end game amp. It doesn't approach the dynamics the breath the warmth and beauty that the Class A Whammy had at all - not even close. It's sound stage was not as deep or as wide and the Whammy was the clear winner. My friend who has all sorts of high end gear and could afford just about anything high end said the same thing when he auditioned the two amps side by side. He simply said the A90 was good but couldn't hold a candle to the WHAMMY. How can it? The whole amp is priced at $499 with marketing, shipping, parts and case all retailing at $499. More than half that number that for dealer cost. Half that for parts and a large portion for case, box and all the other things included with the A90. The parts alone probably cost $50 -$75 bucks at most. Then include labor to make it. Ok so its China but last time I checked they still have labor and warehousing expenses. The WHAMMY is a parts only build it yourself amp - starting at $200 just for raw parts and pc board, no case no marketing no box no shipping and no markup for retail, no labor. And it does not include a $80 Opa 627 set on Dogbrown board. My friend who is an engineer said that amp should cost $1500 maybe even $3000 retail for what you are getting in sound quality. Does it measure nearly as good as the A90 - yes. But I don't listen to measurements when I play music- I listen with my ears and my emotional senses. Does it sound musical and beautiful- does it make me say without any question this sounds so damm good it should be illegal. You see music is my drug of choice. Put the right track on with the right speakers/headphones and you are transported to that time and space like a trip. If an amp is unemotional- its as clear to me as zero water. Sure the amp may be super black quiet but so is my WHAMMY- it's a dead black silent background without any hiss or distortion. But who cares? any amp I audition or review or most of all KEEP for myself should be all those things. I don't want to bring up the absolutely horrible Wyre4sound Intimo I reviewed (LINK)- but I will. It was horrendous and the owner and creator of Wyred4Sound said there was nothing wrong with it. It sounded cheap and plastic compared to my WHAMMY and my retired Gilmore amp. I will not even go into the DAC they included in that unit- simply to state- it was something from the bad days of digital audio- again plastic sounding. Go read my review. Just because it was made and built like a tank- it literately had nothing to offer except a glamor box. Even the display was terrible and old fashioned. It has no place in my home at all. Am I brutal? ummm yea... and I will always be critical when it comes to medium to high priced gear. If the Intimo was $499 it still is a poor performer and at $1500 it should be ashamed of itself. They need to go back and re-design from the ground up. And for all the reviewers who said it was decent or (gulp) even said it was better than good... you should immediately discard them as legitimate reviewers period. Shills is a term I like to use. You see I do not shill - I am completely and 100% independent and say what I think and what I hear.

To clarify who I am and what I am about- so you know, I have 3 systems at my home and I do not have a unlimited bucks to spend on equipment. I only buy what I feel is the best of what I can afford after I exhaustively research and listen for myself. I simply won't buy and many times I return a ton of gear if it is not a stand out product. What do I own? My speakers are Vandersteen 3a Signatures, Magnepan 3.6r and my desk top system which uses SEAS drivers in custom D'Appolito configuration - similar to the Kinoshita Monitor Rey audio KM1V. I edit videos and film on location for professionals- I mix sound for a living occasionally after I film them in person- sometimes I am handed tracks that are terrible masters but am asked to make videos from them without re-mastering the sound. My IMDB page is https://www.imdb.com/name/nm8127846

I am not a flake or hard of hearing at all-I get sound tested by my doctor each year or two. I grew up with sound engineers in the studio who were mixing albums at The Mix Palace and Platinum Sound Recording and The Power Station, Electric Lady Studios Studios in NY to name a few. When I like something I will review it such as the Kennerton headphones I reviewed on head-fi before. If I take the time to review something it has to be meaningful- it must have moved me and compelled me to do so- I do not get paid for any reviews. I do this because I care to set the record straight on what I hear and how I felt about a particular piece of equipment.

What do I want from my amplifier? Richer timbre, wider sound stage, a clean quiet power supply that is isolated from the audio circuits, astonishingly neutral and truthful to the source, with very little coloration to the music. I want a very proper and wide sound stage, dimensionality, and spacial presentation. Toe tapping, head bopping, dancing to the music good- you know... a good time like when I was a teenager. I want it to take me back to the best times in my life and make new memories of just how good a song I have heard over and over now makes me nearly weep with emotion. Is that all? Nope, I want an amp to make me dream of it when I sleep, long to listen to when ever I have the free time. And the amp should not waste any of that precious time with lackluster performance. The amp should create emotion and admiration towards what ever genre of music I listen to with it. I want a party in my head. I want my third eye to nearly open as I transport mind, body and soul to a new plain of existence. I want goose bumps, I want my neck hairs to rise up and my head to tingle. I want to know with near certainty, this is probably as good as it gets - this is my end game amp and probably will be satisfying me for the very near and late future. I want to know this was an investment I take immense pleasure in owning. I want an amp I can look at and admire it's construction and know the maker wasn't some assembly line worker. I have no time to wait around on junk or almost as good products. I want it all and I want it now...

no really I just want all of that and more or at least as close to that as I can get with out forking over a fortune...

It reminds me of some of my favorite stand out parts in the film Amadeus (1984)...


Some amps are forgettable, some passable and some set the bar and exceed and break the bar of excellence- they are iconic and never are forgotten....classic through and through...they are lusted after even.

Does The Apache meet and exceed my expectations in a classic iconic piece of audio gear that will be cherished for generations to come? What do you think at this point?


UPDATE 11/8/20

The Apache does not need any power conditioner or similar devices, just a good power cable from your wall outlet - I tested a few a few inexpensive 10AWG all copper PC from China that looks like a red and black snake- and a TG Audio wire designed for amps- The TG Audio HSRi power cord sounded best with the Apache. I just completed a review on the Tripp Lite IS1000HG Medical-Grade Isolation Transformer designed for very sensitive equipment- I the IS1000HG worked best with my computer and my DAC both connected and isolated on different outlets on the unit. I continued to test and I listened extensively to the IS1000HG while connected to Apache and with my PASS amp- and exactly as Ray Samuels told me by phone- "you don't need a conditioner or isolator with my power supply - do not use a conditioner or anything. Just connect the umbilical cord to the preamp and power supply then connect it to the outlet directly" - he said, "the power supply will regulate what it needs perfectly and no noise should be heard... you will have maximum performance when you connect it to the outlet direct", he concluded. And sure enough it does sound best this way. I should mention with very sensitive equipment like this - precision demands separation from other power supply’s - so to avoid any possibility of interference, keep mindful of placement. Another words- if you want best performance do not stack the power supply on the top or on the bottom of preamp unless using the all metal spikes and supplied disc shaped protectors for a nice air dielectric separation, they also provide some vibration reduction and look really cool if you have the room. Stacking may look pretty but to go one step further for absolute best performance- it is best to keep the two separate by taking advantage of the long umbilical cord - find a physical isolated spot just for the linear power case. This will yield the quietest performance and bring out the best sound- "it was designed this way for a reason" according to Ray.

Additionally- Please make sure when you get your Apache or any other equipment that has an umbilical cord for connecting a power supply and preamp- make sure you connect the umbilical cord first to the preamp/amp and then to power supply. After confirming both power and preamp are connected together the last thing to do is connect the power supply to the outlet. Linear power supply's like the Apache have large capacitors that are designed to charge up and stay charged- so connecting the units in any other order is never recommended. Speaking of staying charged- The Apache as no power switch for reasons Ray Samuels explains as: its always warmed up and ready to go- never getting hot and never drawing more than a LED light bulb in a night light. Like the original light bulb that has been on since It's built - it was designed to be on always and shouldn't have any issues even at 50+ years old- its that well designed. Reminds me of this article: "Time will tell. Located near San Jose California, in the town of Livermore, Fire Station #6 is now the home of the oldest, still working incandescent bulb in the world: The Centennial Light Bulb. The lamp was first installed in 1901 in the old fire station where it stayed for 75 years and always on." If built properly - the very notion of turning on and turning off is the killer of circuits and capacitors and resistors. And I should also add - heat and energy is not a concern here- it should last longer than a circuit with an on off switch which stresses all internal components.


In 2020 - Ray Samuels is still offering unbelievable service and products. The newest Apaches, and for those who have older models can have all the resistors, caps are all upgraded to state of the art best available. And listen to this- Ray says old owners can send their units for upgrades at no charge! what? yes thats what I said- check with Ray for details. You do have to pay for shipping there and back. If you want the best chips added to the older models it's $100. What unbelievable care! This is a hand made amp and takes Ray more than a month and half to complete. He does have them ready to ship as I write this - but only has about 5 or 6 ready to ship- however- understand they truly are very limited. When they are gone - that is likely the end of production for the Apache without a huge price hike. I should also note- Ray always burns the equipment in before shipping out for 48+ hours (usually 72+hrs) and rechecks before boxing it up and shipping. I am doing additional break in with my 1st original Kennerton GH50 Modded by me... the Thekks are on their way from Russia next week after a complete check up at the factory in Saint Petersburg. They were concerned about my review having the crinkle noise when I first plugged them in cold- Kennerton 100% stood behind their headphones and did whatever necessary to make sure they are operating as the reference headphones they truly are. Ray is the same way with product line and customers.

Right now I am absolutely loving the combo of RSA and my original GH50Modded now into Mk2 Status by me- the clarity and whisper black grounds are unlikely found in any so called state of the art 'modern amp' with out spending a ton more than the $3K Ray is asking for these amps... as discussed above- the "volume knob" alone is after all worth $450-500 all by itself right now!

I am enjoying the music like never before with all my headphones - my usual rotation lately is - the planar Indgio Thekks, GH50sModded Version and The JM Edition, Sennheiser HD600 and even my IEMs. Of course usually connected is my modded GH50 - which is still my number one favorite headphone across the spectrum bar none for me (I just completed testing the brand new production model by Kennerton Gjallarhorn GH50 JM Edition made to honor my mod). The new JM Edition is shaping up to be my favorite headphone even surpassing my original mod and seems to be plugged in to my Apache all the time! The Apache really does do sound stage and depth much better than my beloved hard to beat WHAMMY. The Whammy is still slightly - ever so slightly more bassy due to the dual OPA627s vs the more exact sound signature of the OPA1611. I find myself always preferring the Apache.

If you have a desire for the latest and best and want to own a piece of iconic memorable state of the art- classically designed and built by hand by a living legend in our time- this is your next headphone amp and pre amp- I can safely say you can stop reading and go forward with immediate purchase from Ray Samuels right now before they are gone. You can rest assure knowing for sure this is as good as it gets. No wondering, no buyers remorse- this will be a lifelong companion. A joy to look at, to use and listen to in every sense. Highly recommended. -JM

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EDITED HERE: 12/31/20

I am loving the APACHE more and more each month. Recently I bought a bunch of OPAs and have been mainly comparing the SPARKOS SS3601 Single Discrete Op Amp - and I can say it sounds great on top end (if a wee bit too much sparkle on high spectrum frequencies- a bit too much - think hyper Analytical on top end. It's not exactly sibilant but close- The 6kHz to 16kHz range controls the brilliance and clarity of sounds and seems very highlighted here on Sparkos ss3601 ) - this is the truth of what I hear for me but lower end is not close to OPA1611 - the 1611 for me sounds best so far- with Attack much more refined. I do plan on buying a few more OPA's and updating. For now the SS3601 x 4 is not as musical as the OPA1611 x 4. I do plan on trying the SPARKOS pro SS2590 discrete op amp.

I am now using the OPA627bp and it is an amazing warm loving amp now- more impact than Sparkos BUT I need to continue tests. For now- there is no doubt the Apache is a complete chameleon and truly a state of the art design - so quiet and so powerful with no matter the chips installed- but its like getting a new amp sound- very appealing to me. I love the OPA627bp for all it's musical presence and bass impact. It's a lovely sound and it deserves high praise and should be regarded as one of the best OPA's ever made in the last 30 years and probably will stay that statement for the next 30. But I need to continue testing-

I just ordered 4 Sparkos Pros - SS2590 will be here next week I would think... so very fun times!

UPDATED 1/10/21

Just installed 4 SS2590 - and my impressions are complete bliss- warm impact definition and authoritative- a very very great match inside the Apache. The OPA627bp was one of my favorite OPAs for it's shear musicality and ability to loose yourself in the music- never hyper analytical or soft from one end to the other- BUT the SS2590 brings the Apache to a new level of pleasure- past the OPA1611 I originally tested throughout this article. I am listening to Damien Rice and astonished at the pure synergy of matching- this fully discrete high powered Class A Opa is the bees knees-
I am loving each and every second with this combination (SPARKOS PRO SS2590x4 + RSA Apache). Sparkos writes this when comparing IC OPAs to discrete OPAs, "Discrete op amps do not have these limitations, and are a vastly superior upgrade over their IC counterparts. They can run much higher power, have much deeper class A bias, and deliver a much more realistic and detailed sound. Discrete op amps also permit the use of high quality compensation capacitors, and allow for two pole compensation schemes which are impossible to implement in IC designs. All of this translates into a more detailed and engaging listening experience with better imaging and sound-staging than IC op amps can deliver." I 100% agree- this combination is VERY much my ideal set up bringing the Apache to the brink of perfection and I think it's very limits of performance - truly amazing sound. Again, track after track this SS2590 combo is so good I can not stop listening. It's a pure addiction where there are are zero calories, zero chance of anyone getting pregnant, literality zero side effects and no repercussions for inducing a drug like stupper endorphin rush and injection of pure bliss - all my senses tell me this is the ultimate combo I will like the most. And it's only been a few hours since I installed this OPA. I will be doing more comparisons in this review to the other OPAs- namely going back to the 627bp and the 1611 but it may just be futile as my first impressions usually are my best- but we will continue to test...


How lovely this Apache truly is...
Thank you Ray Samuels for making such a statement piece of gear able to continually impress me day after day!

INSTALLED- the 4 single channel SS2590 Discrete OPA