There's been a bit of hype around this amp in the low cost audio space.
I purchased it from https://www.china-hifi-audio.com/ for $708 + $372 shipping = $1080
The price above is also $60 off normal, by selecting EL34 tubes instead of KT88 to come with it.
There is a write up on china-hifi-audio.com from the owner stating the price on this amp will be increasing by tiers over the next year.
By Feb 16th 2021 it will be priced at $893 (vs the $708 I just paid for it)
I will be reviewing this amp in the context that with shipping, somebody can acquire this amp for under $1300.
Let's start with tubes. It arrived with the stock Willsenton 3x 6sn7, 2x 6sl7, and 4x EL34. (9x tubes total)
Right off the rip, the stock tubes are kinda meh (in comparison to other cheap tube alternatives).
I didn't let them burn in. I've read on other forums with burn in they are decent.
While I do generally like, and own many Chinese tubes, they make them in performance tiers.
The "Willsenton" branded tubes are lowest/cheapest tier Chinese tubes. You won't be revolted or even annoyed by the SQ with stock tubes. Although the amp does scale well with better tubes.
The tube set I have it in now, (pictured above) is 2x NOS 6f8g ($150), 2x NOS 6sl7 ($60), 1x Melz NOS 6sn7 ($60), 4x new production tung-sol 6550 ($140) = total $410
The driver 6sn7 and power filter 6sn7 are a bit expensive I have in it now. You could reduce the prices on those to $100 for 3 good strong NOS 6sn7, making an extremely competent tube selection costing only $300.
Overall, depending on if you want to go new production 6l6 / el34 / 6550 / kt88, they all cost very similar for quads. If you're smart with eBay purchases for NOS input tubes, it's quite easy to get a full tube set for $300-400. With a tube set like described above, will outperform the Willsenton stock set by a good margin, but it won't transform the amp into something it's not.
If you want a quick rundown of the features this amp has, see this link.
Let me go over quirks:
#1 Between TR (triode strapped) and UL (Ultra Linear) modes, the TR is quieter, lower noise floor.
This is tested with HD800 headphones. With the speakers I tried, the noise floor is non existent in either mode.
Even in TR mode, I can hear an audible noise floor with hd800, but even the lowest volume music will easily make it completely unheard.
It's a very low hz hum, so it doesn't pierce thru the music like higher frequency noise floors will.
If you're an absolute nut case for pitch black background, and intend to only use this amp for headphones, there is better alternatives.
I wouldn't say I'm a black noise floor nut case myself, but I do like zero noise ideally. There has been tube amps I've tried with noise floors that didn't bother others, but made the amp unusable for me. In this case, the R8 is below that threshold for me. Put it simply, the extremely low noise floor in TR mode doesn't effect my musical enjoyment listening on headphones.
in UL mode, that's different. It's enough to make me not want to use it for headphones. It's still not terrible, and I could see many people not caring that listen at medium/high volumes.
I personally listen at very low volume levels, so UL for headphone is a no go for me dog.
#2 Amp grounding, seems to be a crap shoot on this for tube amps, at least from my experience in owning 6+ tube amps in my audio history.
On my Antelope Zodiac DAC, I had to use the ground lift to remove a very high noise floor. When connecting my Schiit Modi Multibit, zero noise floor.
I did read on forums others had this issue with this amp. Others solved it by using RCA ground lift devices like this.
In my case, I'm just lucky my DAC had a ground lift switch. Then again, my Schiit Modi doesn't have ground lift, and had no noise floor. Seems like this is just something you'll have to figure out for yourself when you get it. I also tested it with a Prism Callia, they did not have a grounding issue with it.
#3 "Pre-IN" RCA input on the back of the amp. It's used to bypass the ALPS RK27 potentiometer, essentially making the amp a "power" amp, vs "integrated" amp.
The amp without voltage restriction from the input has a big noise floor. Completely unusable with headphones, not noticeable with speakers (unless you are using nearfield monitors).
Something to be aware of. As long as you use the CD/AUX1/AUX2 inputs that route through the RK27 tho, you won't have this issue.
I will note that testing with my high sensitivity Omega Monitors, I had to stand at least 4-5ft back from the speakers to hear no noise floor, when the amp was in "Pre-IN" mode.
#4 Biasing is easy and straightforward. Although I would have much rather the amp had probe holes for a multimeter to measure accurate mA values.
It just has a magic eye on the front you need to center for correct negative grid voltage.
#5 I personally do not like RK27, but that is somewhat elitist hifi snobbery. It works great, remote control works great for it.
Once you go over about 30% volume with headphones, you'll hear buzzing. But 30% on this amp for headphones is ear bleeding volume levels. Should be a non issue.
#6 Build quality for a $1300 amp is more than sufficient. Solid metal build, good tube cage cover. Knobs are smooth (not luxury smooth) but good enough.
Buttons have a good click, very responsive. Overall, it's not the prettiest, not $10k+ bespoke build quality, but extremely good for the price point. Oh, also this thing is HEAVY, 60lb.
#7 I should mention this, as I've seen it bother others on forums I've read. The amp is all digital relays for TR/UL and input selection. This means the amp always resets to TR and CD input when turned on, it will not save your settings. For me, non-issue, but something to consider.
#8 It only comes with 6.3mm headphone jack. If you have headphones with only 4pin XLR, you need an adapter like this (which is the exact one I'm using).
Also, connecting headphones auto mutes the speaker outputs. There's no manual switch to do this. Might be a deal breaker for some, another non-issue for me. Definitely has to be mentioned tho.
I might add more to this section later, but these are my impressions thus far.
Off the RIP, it's SQ is well within the range of the amps price. But how does it compete against more expensive or more tailored gear? Check back to find out.
Singxer SU-6 DDC -> Antelope Zodiac Gold DAC -> SE -> R8 -> HD800
Lynx AES16e DDC -> Prism Callia DAC -> SE -> R8 -> Omega Alnico Monitors
A few notes on headphone testing:
From the headamp I've heard, it's good, as a generality. For the price of R8, I'd say it's great in that regard.
I've owned an extensively listened to Eddie Current Aficionado, Eddie Current Studio Jr, IHA-1, Dennis Had pentode headamp, Magni 3+, AURALiC Taurus MKII, Singxer SDA-2.
Probably a few I'm missing. So those are the main amps I'm taking reference from when talking about sound quality for this amp on headphones.
I read on a forum the headphone out impedance on this amp is 150ohms. That seems very high to me, but it's the only refence to this I've found, so I'll have to take it as true.
This means you have to write off anything under a 300ohm headphone, to preserve damping factor for the headphones.
Now, you can use the 8ohm speaker taps with adapter, which would work great for low impedance planars. I read others doing this with good success in other forums.
I will say tho, with my hd800, the speaker taps are far too noisy, unusable based on noise floor. But, the speaker taps (ignoring noise floor) do sound better with hd800 than the 6.3mm input. The 6.3mm input doesn't take a big step down in performance, but it's there. Another reason to possibly think about something else if you are thinking about this amp for headphones only.
Refencing what I read on another forum about planars on the 8ohm taps, the person said he had no noise floor when doing that.
As I said above, it was a big noise floor with hd800 in my personal setup. So while I can't recommend using them from my experience, you might have luck with them. It's a gamble tho, I wouldn't buy it assuming you can get away with it.
Ok finally to some real SQ write up:
(My hierarchy here is: terrible -> bad -> acceptable -> decent -> good -> great -> exceptional)
Soundstage: Overall is good. Good depth, good width. Not compressed sounding at all.
It's not the best at the holographic aspect of soundstage (which is the specific placement of instruments in a 3d space). I'd only give it a decent there.
Macro-Dynamics: I'd say this is the highlight of this amp, it's great, almost exceptional. The 6SL7 voltage amplification stage lends itself to this.
Big band and orchestra thrive on this amp because of this aspect. Impact is always great, hits like a truck, but slightly behind the macro dynamics.
Micro-Dynamics: You could call this nuance. It's decent. One of the weaker aspects of this amp. It's nothing like a good SE 300b/2a3 amp in this regard. Ideally you want an amp that is both a ranging bull (macro dynamics and impact) but also a delicate ballerina (micro-dynamics) when it comes to soft passages and general subtleties. While this amp is a raging bull, it's only a discount B movie (step up?) dancer... whatever you get it.
Resolution: A solid good, but not an inch better than that. It loses some resolution because the Micro-Dynamics are underperforming, as that's a sub aspect of resolution (imo).
Compared to mid tier ($1.5-3k) SS amps, it's great. Compared to the same price bracket tube amps ($1.5-3k), yup just good.
Detail: Clean and articulated. A solid good rating. The opposite of detail to me, is muddiness. To give you a reference on how I differentiate detail from resolution.
I guess what I'm saying here then, is this amp isn't very muddy. It's not crystalline, otherwise I'd be ranking it over a good.
Instrument separation is good to great, putting this here as I believe it's a sub aspect of detail. I will note, one of the biggest aspects of why the 6.3mm is worse than the 8ohm taps, is that the 6.3mm adds a bit of muddiness (also makes tonality a touch warmer).
(If somebody wants a deeper dive on the technical side of SQ, reply with what aspects you want me to talk on, and I'll include it. I kept this part short)
Overall the amp runs warm. With the stock 6sn7/6sl7/EL34, very warm.
With my NOS tube set, brings it closer to neutral (but still warm) (NOS tubes usually run brighter than new production).
If I swapped in all the tubes I know are very bright, you can make this amp lean bright. But you'd need many tubes to pick from to get this.
TR is also much warmer than UL mode. Although I mainly listen to TR mode, will talk on this more below.
This amp also has a touch of sibilance to it.
TR V.S. UL modes:
TR = Triode mode. UL = Ultralinear mode.
The best way I can explain TR vs UL in a general sense, is the difference of hd650 (TR) to hd800 (UL).
UL just lifts a warm veil that sound has. Removing the veil doesn't make any of the technical assessments better from above, it's just something that's removed.
Again just like hd650 vs hd800 sound.
Now, I've only been using TR on this amp, because UL does more then just remove a veil. It's also shoved the soundstage depth in your face, and kinda kills it (meaning it takes away depth)
This is a perfect example again of what something like Utopia vs HD800. Where at first Utopia seems exceptionally detailed and clear compared to the hd800, but it's just a parlor trick. The Utopia is just shoving the depth back into a flat plan, and into your face, so details appear much more visceral.
And that word is pretty great in explaining the overall aspect of UL mode, it's more visceral. It trades nuance and depth, for cleaner transients, and more in your face details, while presenting a less veiling and less warm signature.
If you've been reading up to this point, you probably know why this is an issue. From the technical write up above, one of the weaker aspects of this amp is nuance. Switching it to UL mode makes this even worse. On the level of an SS amp for nuance (sry SS amp lovers). UL takes away some air too.
I can see some people loving UL, or hating it. It changes the sound so dramatically I don't see many people having a neutral opinion on either choice.
Studio Jr.: Annihilates it in micro-dynamics and nuance. While at the same time, the R8 would annihilate the Studio Jr. in macro-dynamics. Opposite pros/cons the two amps share.
Studio Jr. also suffered on speakers from just being low watts (4wpc). In this sense, overall R8 is much better for speakers.
BoyuuRange A50 MKIII: Wins in nuance and subtly, resolution, and the aspect of holographic soundstage.
They both have close to the same soundstage depth and width, but A50 places instruments within that better. A50 also has better timbre. R8 still has amazing timbre, it's a tube amp after all, but ya loses to A50 for that too. R8 has better macro-dynamics and impact than the A50. Also, R8 can do headphones, something you can do with the A50. The A50 in general has a higher noise floor than R8 (meaning don't think you can just connect headphones to the 8ohm speaker taps of A50). But, the A50 noise floor for speakers is a none issue.
Denon PMA-2000r: High current mosfet amp. Bought it based on glowing youtube review (RIP), I paid the going price for it which was $600. It produces 80wpc, in class A/B.
Maybe this amp really is just shit in a general sense, but for me it reaffirmed why I hate SS amps. Sterile, lifeless. While most of the pure technical SQ aspects chop up close to R8, nothing it has exceeds it, while tonally it's just a POS (meaning bad, not even an acceptable level for me).
Custom Dennis Had Pentode headamp: Using the R8's 6.3mm headout, the DHP amp is overall better, while only losing in macro-dynamics. Which is crazy, because the DHP I specifically had custom built to push macro-dynamics for headphones haha. If you can get away with using the R8's 8ohm taps for headphones, it comes a lot closer to DHP in nuance and timbre, still a bit short tho. I paid $1650 for the DHP as reference. If you wanted to stick resolution/micro-dynamics together, and give them ratings... Studio Jr. = 9/10, DHP = 7.5/10, R8 = 6.5/10, Denon = 3/10.
I will add detailed sections for all the tubes I've rolled and how they stack up, if requested. Don't want to put in the work for this if nobody cares tho.
Final Thoughts / Price Considerations:
For the $1080 I paid for this, makes it a great, bordering on exceptional piece of kit. For $1300+, it's just great. Great is great tho... haha.
Will this compete with pure DHT SE $3-5k amps, no way. But, it has more wpc then anything but an 845 DHT amp, 2a3/300b won't come close. So if you need the watts, that's a thing.
Do you want a very nuanced, pitch black background headamp, I'd look elsewhere, even for $1300 the R8 costs.
The true value of the R8 comes from being a great speaker amp, that happens to have a good headout. If you're not planning on using speakers with it now, or in the future as an upgrade path, don't buy it. If you want something purely just for headphones, I'd recommend the SW51+ from this guy https://www.superbestaudiofriends.org/index.php?members/zampotech.6896/ ($450), or the DNA Starlett http://www.dnaudio.com/DNA-Starlett-headphone-amplifier.html ($2000)
If your budget expands way past $1300, or you have the ability to save, I'd recommend the Elekit TU-8800 (pentode version) or Elekit TU-8600s (300b version).
Fully kitted out with Lundahl output transformers, they cost about $2.5k, so over double the R8. They also only produce around 10wpc, so half the watts as R8, take that into consideration for your speaker choices. BUT, both Elekit support headphones, and would both be better for headphones than R8. And if you can get by with the higher price and lower watts, they both will also easily outperform the R8 on speakers.
To boil that all down them, this really depends on your budget, and what you want out of it.
I watched at least 5 different youtube reviews on this amp. Many of them were saying it competes with all the $5k integrated amps they've tried, stuff like PrimaLuna.
I don't have the vast listening experience of audio reviewers that have a constant cycle of gear coming in. But, it makes me think the $5k integrated amps they've been given to demo are all shit. If this R8 competes with $5k integrated amps like PrimaLuna, that only tells me all those other amps are horribly overpriced.
So... Is this amp as hype as other forums and youtubers have made it out to be? For the baseline $1080 I got it for, I'd actually say yes. If it's exactly what you need, you need at least 25wpc, you love the sound of tubes (like I do) and you want a burner pretty decent headphone amp to boot. If your budget can expand to $2k+ and you don't need everything the R8 offers, I'd say skip it.