Great test Johan! 👍 They all sound good and close. If I have to pick one, I'd say the RCA had a presence that the others lacked in comparison. Cheers Jonas
Those GECs are the bee's knees. Honestly the new tubes have nothing to be ashamed of, and the brightness of the beam tetrode 6L6GC helped it hang in there. I've never had GECs before, but still have RCAs, Sylvanias and GEs. Thanks again Johan.
Merry Christmas Johan!!!! from Sunny Sanpedro California! Your the best Tone Master! and you always make it easy for us Guitar Nerds to get the best sound we need without your help it would be difficult Rock on brother! !!
Hi Johan, once again, another great video, and thanks for all the time and effort you put into making these videos for all of us rock n' roll enthusiasts. The RCA sounded the best, it has a bit more bite which i like to hear, all the others sounded very similar at least IMO. Brilliant work my friend and keep on rocking!
Johann!You don´t even need electricity any more to make anything sound good!You´re a Legend!Thx for the cool videos!Keep on rocking!Greetings from Austria!
Interesting. The only difference that I heard was the low end response between the tubes with the el34 being a little "softer" and the 6L6s being a little stronger. Well done!
It may just be my speakers, but I had a hard time telling the first three apart at all. The last one sounded a bit brighter, but not a whole lot. Thanks Johan.
I won't bother saying what I thought would happen, because what happened wasn't anywhere near as extreme as I thought it would be. A person could easily use any of those tubes and just vary speakers. In the meantime, I received my new Fender Elite Tele today, but still can't open it for another couple of hours because it was pretty cold over night so I'm letting the box come get to room-temp to be safe.....one would think getting older would make being patient easier....but not when it comes to new toys! Thanks for the video Johan!
Subtle but definite differences between all of them. I like to low end of the KT66, and the RCA has a slightly different color tone as well. I think my least fav was the Marshall tube, but it certainly gives the Marshall type overdrive tone. Another good video!
They all sounded very similar to me. I wonder if this is because the amp had just one power tube. If another amp with a different configuration of tubes was used for this test then perhaps there may have been more variation in sound between the tubes.
best sounding was and most distinctive was the RCA 6L6. Second best was the EL34, but it was really close to the other tubes in sound quallity. I used to run a mixed quartet of 6L6"s (metal envelope Mil spec) and EL34"s. Best of both worlds.
Cool video, I think I like the KT66 the best. Johan do you take requests? Is there any way you can get your hand on a Bogner Ecstasy 101B? It is supposed to have a really cool "Plexi" mode, would love to hear it through same cab as some real plexi's.
+Tommy Köllner (Sonofamustangford) Tackar Tommy! Ja jag tror att det allmänt finns en övertro på att bra ljud beror på enskilda viktiga faktorer, medan det egentligen är många små utbytbara bidrag.
i liked the RCAs, the KT66s were a close second. the RCAs sounded nice and clear, with extended highs and lows, i liked the midrange character they had too. makes me want to track down a pair and build a JCM 800 2204 ish clone. nice video buddy.
wow, perfect timing for me.....I found a 1965 Silvertone 1484 at a garage sale, with 2 original RCA 6L6 GC's and 4 amperex 12ax7's.... testing the new JJ's and others. The only one I could hear a difference in your test was the RCA, slightly softer/warmer......maybe the GEC too.....same in the Silvertone compared to JJ....though new JJ' made the Silvertone clear and louder......new versus old. thanks as always.
KT66 - Put out a little more volume than the rest, had a little more bottom end. Lots of top end (as bright as the RCA), a little cleaner sounding than the others. EL34 - Least amount of bottom, smoother top. More centered around the mids. Less definition and clarity than the other tubes. All of my favorite amps use EL34s, yet this was my least favorite tube of the bunch here. JJ 6L6 - Balanced sound. Less low end than the KT66, had more top end clarity than the EL34, but was darker than the other 2. The response seemed to be shifted a little lower, overall, than the RCA. RCA 6L6 - More top than the JJ. Maybe less bottom end, but it's brighter, so the top end seemed to take over more. More clarity without really being any harsher, but I think I preferred the JJ's darker and lower tone. That's how I hear it. Great comparison as always, thanks for sharing!
i understand autobias. but i wonder if it also automatically adjusts primary impedance on the output transformer. from 6L6 to KT66 is quite a stretch using the same impedance. might not show the capabilities of each tube really. but still good comparison and i dont like to admit that the differences are not very big at all. i love rolling tubes :D
black plate rca had a bit more bite and a bit less mids, and also more open than the JJ. Definitely my favorite, but that was my opinion coming before I watched the video. I think we love our hate what ever we want to notice, and that influences or playing style. Excellent video.
I love this kind of demo, especially the long try at the end ! :) Now my 2 cents : RCA : Very balanced and vintage/soft 6L6. I really would own a pair of it ! JJ : Modern, high fidelity, maybe too much for my taste, too brigth/harsh. EL34 : Typical of marshall sound, i dislike their cutoff low ends but i like their limitation in the highs (it's avoid the sharpness of the 6L6) and their agressiv/percussiv mids. KT66 : Better than the JJ 6L6, works in the same category. I don't find them really musical or well balanced. Natures vids on the right are also great : beautifull trees, mountain of rocks, nice reflect of the nature life, all things i love IRL. Cheers man !
The RCA was more open with more mids . Kt66 was close to RCA with a flatter response .The EL34 was the most compressed with early brake up. JJ 6L6 had flat response less output than KT66 & RCA6L6 . Great Video !!\m/!!
Hey Johan, I just came accros a Marshall 2201 30w Bass combo from 1977, do you know this amp ? it looks like really rare (and uggly xD ) but might sound right, just like a Lead 12 louder and in a 2x12 format. On top, a lot of them were hand-signed by Jim ! Any thoughts ?
No, unluckily... It is at 700 kms... But it is sold for 50€, which is more than a deal with 2 70's greenbacks in and Jim's signature ^^ Damn, I was hoping that you would know this model but no problem, if I manage to get it, i'll give you a review, comparing it to a lead 12 and a 18w plexi clone. Thanks anyway, cheers !
It is hard to believe that there is no dramatic difference. I once replaced JJ 6L6GC with nos russian 6p3s-e in JMP 2204 clone and difference was night and day. I couldnt put my guitar down. But I havent recorded that tube swap, I wish I did. I recorded my strat with my handmade bridge pickup and replaced it with also my handmade singlecoil sized P90. Playing live difference was huge, but recorded sound was almost the same. Just a little more low end. I guess recording somehow makes big differences hard to notice. Maybe my micing technique is bad. Johan, playing that guitar live you heard same differences as in youtube video ?
+kumpiz Yeah, it sounded like that in the room too. Often when we change one thing with an amp we unknowingly end up changing several things making the difference bigger. My experience is that tubes are one of many small contributors to good sound. Cheers Johan
Ameer I'm giving you my thoughts and these can be used for many posts here. The American sound and the British sound is not only on the tubes. It is on the speakers as well and other factors. But the EL34s used in the same amp have more high mids and highs while the 6L6 types have more low mids and rounder highs. The Jensen speakers that contribute to the American sound have more highs than Celestions and not too many high mids. Celestions usually have more aggressive mids. I love using my Marshalls and Hiwatt through Jensen speakers too for more clear and bluesier sounds.
And there is a difference even small. The recorded sound loose some feeling compared to what you really hear and when the amp is not cranked these diffrences may be more clear.
I do understand - but there are numerous ads/videos I've seen that promote their amps by saying things like "and they've got a set of EL34's to give you that famous British tone".
The GEC KT66 and the RCA 6L6 'black-plate' have a nicer sonic appeal. Of those two I prefer the KT66 power tube as they sound thick and juicy. Which was one of the reasons I bought a Marshall #2466 'VintageModern' head to add to the 'herd'. I also upgraded the transformers to Mercury Magnetics 'Axiom' line of iron for that amp along with NOS pre-amp tubes as well. That particular head driven with a 'good' dirt pedal, J Rockett Audio '10 ton Hammer', in the low dynamic range pushing an EVH 4X12 cabinet is pure sonic nirvana. And only gets better with a half dozen or so Belgium beers! Cheers.
Kind of surprised with the results since I've done a similar test at home with a Jet City Picovalve. I couldn't hear a discernible difference in your tubes. The exception was the 1960s RCA which seemed to be breaking up slightly less. My test at home, I could hear a pretty big difference between the KT66, EL34, and 6L6. Perhaps it has more to do with how the power section of the amp is driving the tube.
it configuration. if class b configuration the tube are likely to not brake up. they only make current of signal bigger. also how it interacts with power transformer. tube have capacitance and transformers have inductance. this two properties interact with each other in class b configuration it the power transformer that distorts.
Johan, I'm curious. For last couple videos,, you put landscape video alongside your guitar playing. Is there any particular reason for this ?? For the tube itself, I can hear subtle different. But, it isn't enough to prefer one tube over another.
RCA Blackplate 6L6 all the way, but I knew it would win. Got a pair in my '64 Pro 1X15. Beats every other tube I've tried by far. Good NOS matched pairs are fetching outrageous prices on ebay these days so the secret is definitely out.
Surprisingly the GEC KT66 and the RCA 6L6 sounded the best. Somehow the JJ 6L6 sounded a lot like the EL34 at least to my ears. I'm sure in different amps these would all sound different due to different biasing and voltage. But there is something about some of the older tubes that is not reproduced with the new ones. Different anode material perhaps?
+Andrew Shepherd Yeah that would be interesting to investigate. Back then tubes was a central component, today it's a peripheral enthusiast component. Cheers Johan
wow...... Ok the KT66, 6L6 rule in my opinion. I knew it allready since I tried them. But that blackplate is smokin'. I love them due to the lower mids fullness. Any comments about the amp?????????????
hahaha. Thanks Johan. i'm glad you like it. It really fits and gives such a sound for bedroom levels. It also does the semi cranked bluesy thing great. Thanks.
the GEC has something that goes missing with the EL34..The 6L6 kinda brings a little bit of it back along with something it only has....The RCA like goes all raggid and sags a lot. So I liked the GEC and the 6L6 best in this amp. Just more material there in the sound. Good job Johan!
Hey I wanted to add that when you started muting the guitar and running through all the tubes is where I could hear all the differences best. You give it low and highs at there loudest in a way like that which sends all those frequency through tubes pushing them so you can hear how the respond.
The 2 more recent ones sound more trebly - not well balanced. You can tell right away from the first riff! The vintage ones sound similar, the GE has a little bit more lows. Excellent video as always
I prefer the RCA, it's fuller and more dynamic than the others. KT66 sounds also good, while the Marshall EL34 sounds thin and fizzy (maybe that's why most modern Marshall amps sound thin and fizzy too?)
KT66... very full range... RCA very warm to my ears while EL34 and JJ 6L6 sound pretty similar, again, to my ear... i should try some on my Egnater Tweaker 15 that is cathode biased and works with every pair of eight pin tubes... (a very great sounding amp with JJ 6V6, while stock uses a pair of Electro Harmonix Egnater branded..)
Totally agree. KT66 has the "edgiest" charakter, non compressing and full rangy. The SVT EL34 and JJ 6L6 are close to each other, can't really tell the difference there. The RCA however blew my mind - full body with very high detail. Tubes are great, aren't they?
Personally I was totally digging that RCA tube. Although very subtle the difference was between them all (except the KT which I thought was the most different sounding). The RCA had some gnarly harmonics going on in the mid range and still had a little thump in the bottom. The JJ wasn't bad. Surprised how similar the EL and the 6L6 sounded here. Since the same circuit is running the different tubes instead of comparing two totally different amps the difference is subtle.
Before any comparison using old valves, they all need to be tested on something like a Amplitrex AT-1000, to see if they are all still strong gain wise, and close to factory rated new spec., otherwise its a more dubious outcome. Weak testing valves, means less bass response, more compression. But... for the sake of the fact Johan went to a lot of trouble to satisfy his fellow tone chasers like myself..... RCA 6L6 more open, least compressed, clearer, more even in the mids. More headroom. Great for a blues sound. GEC KT66 also slightly open, slightly more extended frequencies in the low end, thicker low mids, slightly louder. Marshall EL34 (AKA Svetlana Winged C at a guess) breaks up a bit earlier, slightly congested/brash in the upper mids. Great for Rock. Sounded slightly quieter/ compressed, less bass. Does it still test strong after 6 years of use? JJ 6L6 breaks up later, slightly wider/ more frequency response to EL34, slightly more open to EL34. Good quality NOS old valves are almost impossible to find and expensive these days, so sticking to using JJ power Valves. JJ EL34 are good enough for AC/DC live, so good enough for me.
Marshall and Les Paul, what could be better? Nothing! Unless it were my Marshall and...what ever humbucker you want to plug in. You got skills JS, play it loud and play it proud.
Most gain on the EL34. On the higher register KT66 and the EL34 sound almost identical. The 6L6 has the 2nd most warmth but falls between KT66 and 6L6 GC on gain. The 6L6 GC has the most warmth and the least gain.
GEC sounded best, but all were cool. I heard from a lot of players, and some guys that have vintage amp and guitar places, that no real good tubes are made anywhere anymore. That there are still some working originals and some original never used ones here and there for sale. They all said all the tubes made now are not near as good as the ones from the 50's- 70's. Is that really true, or are there some decent ones made like the real ones?
I prefer the KT66. Since I use this one my songwriting and overall guitar skills have increased dramatically ; )) ...even my singing. Just joking, nice video! But as I "said": There are faaar more important things that contribute to the sound.
ive been tone searching so much i can hear a huge difference with my cell phone speaker. suggestions for dsl40 please. and does the amp have to be biased?
This affirms my distaste for jjs . I retubed my 22 watt with jjs. They were out before the night was over and replaced with cheap Chinese tubs that sounded way better. I sense started useing tung soul and love them.
Less differences than I'd thought. But I like the KT66 best. My son plays a JVM 210H with 6L6s 'cause the tech didn't have any EL34. The difference may increase if you got two biased pairs....
Definitaly, the KT66 beats them all. The most different one was the EL34, waaay more agressive and gainy, with the 6L6 it seems like you have to effort to get the sound. The harmonic richness on the KT is what tells it apart, IMHO.
I did a similar comparison a few years ago on the metroamp forum. Power tubes don't change the overall character of the amp, just certain qualities. The other big difference is in the feel of the amp when you dig in, which is hard to perceive on a recording. Here's a link to the one I did, you'll note it's tough to hear the differences until you know what to listen for: forum.metropoulos.net/viewtopic.php?f=13&t=44130
Not a lot of difference in this example. I've got a Metroamp JTM-45 and the GEC KT-66 are unbeatable. I've tried all kinds of tubes (eg Gold Lion - cold), no comparison in the body and richness of the tone. However I did find, and others have said the same, the old Valve Arts, around 7 or 8 years ago, sound splendid. They get close, but have an interesting "dryness" that gives a lot of character to the dynamics in your playing!
Rca had something the others didn't NOS wins, but for the cost. This is why I use an rca nos 7025 and a sylvania 7025 in holes 1&2 in my Soldano. Then some JJ's. NOS is just too costly and getting harder to find for power amp tubes.
Subtle sound differences as they may stick out more the better the quality of the source of the sound is, power tubes in my opinion are the last thing to take care of in the whole electric guitar chain. Good quality cables improve sound in a more noticeable way same as preamp tubes, speakers, components of the ampifier, specially transformers, then pickups, strings, good quality pedals... so when the cake is finally out of the oven then the covering of it might be chosen picking the kind of power tubes which really hit the spot in that particular sound and that particular guitar player's taste. Doing it the other way around is a waste of money cus those Gold Lion KT66 for example are around 500$ a pair for not being able to enjoy them fully.
RCA! the EL34 is probably my least favorite... but to be honest i expected the differences to be more obvious overall. so i guess they would all be fine for me ;) maybe it is more about the feel?
Thanks, I am looking for a portable low watt replacement for my JCM2000 DSL with an fx loop , “real” distortion and volume-roll clean, to adopt to my more modern rock sound, you’ve tried so many amps, could you give some advice? (OR15 sounds kinda good too imo)