Riverstone Audio - Tested/Matched Pair (2 Tubes) 7-Pin JAN 5654W Fully-Tested Vacuum Tubes - Upgrade for 6AK5 / 6J1 / 6J1P / EF95 - JAN 5654W Platinum Grade Pair

This alleged matched pair of 5654W vacuum tubes were my first tube purchase from Riverstone Audio. Very impressive packaging – safe, secure, and it looks like they take pride in their work. As I do not have access to a tube tester, I have to take Riverstone’s word on them being matched and on their measured performance specs. These tubes replaced the cheap Chinese crap tubes that came with my equally cheap Douk Audio T3 Plus phono/headphone preamp. The T3 Plus itself is underwhelming, but for the price that’s what I expected. However, for relatively little money, these 5654W tubes made a subtle but very noticeable improvement in sound quality in my T3 Plus. And that improvement was well worth the cost of these tubes, regardless of the following concern: HOWEVER – and I’m hoping Riverstone reads and responds to the following comment – I am a little concerned that these 5654W tubes may (or may not) have been counterfeit, or not completely advertised honestly as real GE NOS / New Old Stock tubes (actual NOS means they were manufactured many decades ago in tube’s “muscle car era” and have never been used since. Such NOS tubes command very high prices now, due to their reputation and scarcity). Here’s my concern: The green ink printed labels on the outside of each tube appear to be printed over, and on top of, other labels in light gray ink that appear to be on the inside of the tube - question mark ( ? ). Hmm. While this is unlikely to be an actual problem, our friend The Internet is full of counterfeit knock-off tubes that are “advertised” as NOS / New Old Stock but are actually modern tubes that are not manufactured to the same old-school tolerances and specifications. Similar to cheap Gucci and Louis Vitton handbags, etc. As these Riverstone 5654W’s have both green and gray printed labels, one on top of the other, it makes me doubt their true manufacturing / vintage. That said, they sound better than the tubes I replaced them with, and that’s all that really matters. In addition, a deep dive into research on GE 5654W tubes from other vendors also shows them as having the double green/gray printed labels, so at least these Riverstone’s are no worse than that competition. All that being said, for the asking price, these Riverstone 5654W’s are well worth the asking price – they simply sound better than the cheap factory installed tubes I replaced them with, and for less than the price of dinner out this evening. As this 5654W tube and its numerous compatible variants are not commonly used by tube amp/preamp manufacturers, it’s difficult to get trustworthy research on them no matter which vendor you consider. Even tube “Godfather” Brent Jessie’s website has scant info about this tube family, and Brent Jessie’s website is the most trustworthy for vacuum tube research.

Riverside Audio is my go-to for these tubes. I remember when tube testing kiosks were in regular stores (Sears, mid-60’s). Makes sense to match them for two channel music applications, and Riverside does this; i can’t. They come well packaged (with an “if seal is broken” notice, an “extra mile”) with documentation of the testing. What this means to me, along with my listening experience, is confidence in the brand. I paid more for a pair of 1940s vintage tubes but it wasn’t long before one burned out, leaving me with an orphan. Better to go Riverside, all of mine still work, though I can’t estimate how much time I have in them, at least a couple years in one pair. These are worth it, especially at the current price, under $20 a pair in early ‘21. What they add is an improvement in the depth of perceptible soundstage, vs. a more 2-D experience. Less potential for listening fatigue with the treble. No serious sacrifice in the details. When I have them out of my signal chain I can still enjoy the music, but then a restlessness sets in (“Audio nervosa?”), as if something’s missing. Knowing what that is means in theory is that there’s a possibility of it being all in my head — but then that’s where my ears attach. Then back in they go, and it’s “ah ...” I use them in three of those inexpensive “Chi-Fi” preamp/tube buffers that Amazon sells, in three different stereo systems, all with class D amplifiers, after many years of the same A-B amps, for something different. My first impression of class D was skewed by having it drive brand new speakers, which (seriously) benefited from a good period of break-in (believe it or not). The sound signature of all the class D I’ve heard is, to me, detail-oriented, flat across the frequency range (so far as I can tell), neutral, possibly a tad dark, which I like, after years of relative warm & creamy. But in that first combination I was reminded of the difference between early remastered CDs of rock music I had on vinyl — the analog knocked it out of the park. CDs sounded more compressed, with “digititis” leading to listening fatigue. Not so anymore. I have Riverside tubes between one of those little TDA7498 amps (32v 5 amp power supply) driving early 90s Definitive Technology DR7 speakers. One between an ICEpower 125ASX 2SE amp and Dayton Audio MK442t speakers. Even in my work-in-progress endgame (if there is such a thing) system, my sources to a Schiit Saga + and a made in Ohio VTV Hypex NCore 252MP amp, as far up the class D chain as I’ve gone, driving sweet Q-Acoustics 3050i speakers (for me the balance between two channel simplicity and enough bass to preclude a subwoofer). An issue I had was wanting to push the volume higher on certain music when using my current budget streamer, a discontinued NEXUM TuneBox TB20. The Saga has little gain. My heretical solution was to put a tube buffer back in the chain, between the Saga and the amp. Two preamps, but “Ah ... just right.” System synergy. So especially if you’re new to class D, or need a little extra volume (I set the buffers to around 11 o’clock), for not much money I found they worked for me.

I purchased this pair to replace the tubes that came in a Douk ST-101 Pro. The amp will not power on with these tubes installed. When I reinstall the old tubes, it works. 2/26/2026 After reseating these a few times, they are working great. Just as advertised and improved the sound.

I have a Little Bear tube preamp. To be honest, I just wanted the bougie glowing tubes with my turntable set up. ...It was horrible. It was noisy and just flat. Didn't sound good. I did a Google look to see if there were modifications people were making to him to make him sound better. I read one person changed the tubes for a quality set of tubes... Claiming the Chinese manufactured tubes it came with the unit weren't good. So I ordered these and gave them a try.... The difference is stunning. They are quiet, accurate, and balanced. I haven't measured the tube specifications to see if they met the matched claims of less than 3%, but I have no doubt that they do. Awesome matched NOS product at a super reasonable price! They were well packaged and obviously intended to be sold together... 100%. I'll buy from these guys the next time I need tubes!

made my amp sound better

I was really pleased with these tubes. They seemed to produce a much clearer signal. The guitars especially sounded almost like they were in the room. I would definitely recommend these tubes.

As others have done with my Dayton Audio HTA-200 hybrid tube amp, I also decided to swap out the 6K4 tubes for these or "a" pair of 5654W tubes. To test the difference I uploaded a decibel meter to my iPhone. Maintaining a consistent or fixed mid-range volume, I auditioned about 15 seconds each from a particular starting point in four different songs (Low Spark of High-Heeled Boys/Traffic 5:33, Berlin/Fenne Lily, 1:24, You and Your Friend/Dire Straits 3:00, and Hurricane Party/James McMurtry 1:35). The difference was so jaw-droppingly apparent it rendered further comparison absolutely unnecessary. My 50W/ch@8-ohm amp's volume increased like it were now a 75W/ch@8-ohm amp, EASILY half again louder with seemingly unlimited headroom. Gee, I didn't KNOW it was legal to put PLUTONIUM into a pentode vacuum tube -- like catching lightening in a (Tube-Like) bottle! These tubes are worth e-v-e-r-y s-i-n-g-l-e p-e-n-n-y of the proportionately diminutive $24 upgrade. [Two things to note/mention: (1) I found a pair of 5654W tubes for $20 (i.e., $4 less) on Amazon as well, so asked the A1 chat service, Gemini, why it might be worth spending the extra $4 when this tube's description added the words, "fully tested." They related that it was unequivocally much better to get the set marked fully tested for perhaps a half-dozen quality control reasons which completely convinced me this was the wise way to go; and (2) 6K4 tubes are triode tubes noted for warmth and emotion. Conversely, 5654W tubes like this provide a higher gain and better stability for a more clean and detailed sound. That said, maybe don't throw away your 6K4s depending on how you may feel.]

Riverstone tubes are an incredible upgrade to the Ayiama T9 Pro. The stock tubes are decent, but when you get a matched pair that has been thoroughly tested and doesn’t require a burn-in period, you get to see just what that little amp can do. Easy to install, they cost a few bucks but are absolutely worth it. The warmth in tone was a pronounced improvement, and cranking that little guy up I didn’t hear any strain. If you read audiophile forums (as many of us do), you’ve likely heard that these are the best option for this amp. They are. I tried other “matched” tubes and the difference was night and day. Clearly, Riverstone know what they’re doing and have the tools to do it right. Why are you still reading? Just add them to your cart already!