Will Vacuum Tubes Change Your Amp?

Many of us have spent a great deal of time & money swapping out vacuum tubes in our amps in a quest for "better tone." Let's apply the scientific method & see if it was actually worth it!
This test was made possible by using the incredible TWO NOTES Captor X: Click & affiliate link & help out the show!
Sweetwater: imp.i114863.net/okWLE
Thomann: www.thomann.de/intl/ca/two_no...
0:00 intro
1:20 "special" tubes???
3:40 Human Perception
4:55 applying the Scientific Method
7:30 Joyo Zombie
10:14 5150
12:43 Power Tube test
13:56 For the Tone Elitists
16:58 Results
18:54 Conclusion
Many thanks to ‪@jacksonwarddrummer‬ ‪@erikarko‬ and John Souki for the incredible performances!
About Spectre Sound Studios:
I'm Glenn Fricker, engineer here at Spectre Sound Studios. I love making records, and after doing it for sixteen years, I want to pass on what I've learned. On my channel you can find tutorials on how to record guitar, bass, real drums and vocals. There's reviews and demos of tube amps, amp sims, drums, mics, preamps, outboard gear, Electric Guitar, Bass Guitar, and plugin effects.
We've covered Moon on the Water, played Bias FX, given you the absolute best in Stupid Musician Texts, ranted & raved about bass guitar, and this channel is where The Eagle has Landed.
Everything you've wanted to learn about recording Hard Rock & Heavy Metal can be found right here on this channel!
I also respond to your comments & questions: The best make it into the SMG Viewer's Comments series of videos. Loads of fun, lots of laughs.
Thanks for checking out my channel & please subscribe!

[@achannel1818]

You'd think that people would be happy about not needing to buy rare, discontinued valves to get vintage tones.

[@reverb508]

Only reason to buy NOS tubes is because they’re generally made better and will last longer. Of course, that all goes all out the window if they cost a ton more than the modern tubes

[@chuckyz2]

Lets hope. More of the goods for us in the know.

[@vintagetone22]

My friend nothing beats an el34 mullards made in the 50s or 60s .please.stopthis digital crap.

[@StallionStudios1234]

@@vintagetone22 hmmm that might good to power my penis when I have erectile dysfunction. Probably makes me last longer?

[@chance2smoke]

But then how will I feel like I'm better than others without building technique?

[@Anvilshock]

But there IS a noticeable difference! When I changed the tubes in my amp, the FEEL of my _wallet_ was so much lighter!

[@chickenboyyyy7860]

🤣🤣🤣

[@Anvilshock]

@Overpaid Producer Gotcha!

[@fantaztikbeatz]

Hell yeah geesh 😆 🤣

[@beavcleav3086]

But was it warmer?

[@yunamadsimackomen881]

Oh man! You really got me to crack up there.

[@Fiddling_while_Rome_burns]

This test is complete bunk, everyone knows changing tubes doesn't work with a red guitar.

[@gogglespaesano2931]

Now that was funny! And probably accurate, too.

[@bradly373]

Hahaha 🤣

[@Wargasm54]

Facts.

[@yunamadsimackomen881]

Good one!

[@randybach4581]

🤣🤣🤣🤣🤣

[@bghammock]

The mic movement changes were crazy eye opening.

[@BlueBarrier782]

Sadly, the things guitarists don't care about does the most for their sound: speakers and mics. You know, the stuff that actually makes the sound waves and records them?

[@ChuckHaney]

The other thing that perpetuates the myth is this: First, tubes can and do go bad. If you've been playing your amp for months or years with bad preamp tubes you may not notice the amps less than stellar sound. You put in new tubes, maybe they aren't the same brand you had before, you turn on the amp with tubes that are actually working correctly and suddenly it sounds good and you figure it must be the new brand you've used. Wow! "Those Jim-Bob tubes are GREAT!!!" Maybe, but really it's just that your shit tubes sounded bad.

[@sski]

Seen it happen.

[@fletcherchambers7175]

I'm sure this scenario s a major force behind tube myths...

[@portlandshomlessproblem1728]

Me and my dad always have bought jj’s because euro tubes is local to us, they sound good to me. We’ve talked with the guy who ran sunn amps who now builds custom tube amps and he uses jj’s. Why? You ask, because euro tubes is local and he gets a good deal on tubes. The only major difference in tone is old worn out tubes vs new tubes

[@ravenslaves]

...A lot of players used to take brand new tubes, mostly power tubes but also preamp, and shake them to get them to break up a little sooner and round off the tone a bit. It works...you've heard it on a lot of classic albums...I wouldn't do it...but it does work.

[@weinderdog1184]

This makes the most sense

[@OlaEnglund]

Camera shifts looking kickass man!!!

[@SpectreSoundStudios]

Thanks for that advice, good sir! It really sped up my editing!

[@ssmstudio1476]

@@SpectreSoundStudios 😂

[@LayMyBurdenDown]

Happy to see people helping each other out! Ola I was asking Glen about his thoughts on the Evertune.. Has he done a Solar guitar review?

[@blakecurtis7809]

@@LayMyBurdenDown I think he has. Look for studio workhorse caption if I remember correct.

[@daleederboy4777]

i wanna keep this comment at 69 likes

[@alexholmes6333]

Thank you for such a thorough and precise test, we need more of this in music. Especially loved the "warm doesn't mean anything" part.

[@sumyupee]

The biggest shock to me was how close the el34s were to 6l6s. That's nuts. It's nice to know how little the power tubes actually matter in regards to tone. Thanks for the scientific approach.

[@mrffoeg]

The difference is mostly in the way they clip. The 6L6s clip harder at a higher threshold

[@googuser3145]

I have a 3ch Recto, and there is definitely a difference in in the overall EQ. I find the lows with 6L6's almost overbearing and the EL34's just right (for a recto). Also find the lows are more focused with EL34's. All JJ for my tests... Either way still sounds like a recto...

[@Red.be89]

I wonder if the el34s or 6L6s were actually being pushed hard enough to start clipping. I wouldn't expect much difference if they aren't being pushed hard. Also curious to know if biasing each set 'properly' would change their response. I doubt you're going to hear a different EQ response, but I would expect different output level and clipping point. MAYBE even hearing clipping at different frequencies first.

[@popkorn256]

In the end, I'm not so surprised by the results but more by for how many years I heard that tube swap tone bullshit

[@calebkey2050]

EL34 grids are approximately twice as sensitive as a 6L6, and will put out a bit more power in an otherwise identical circuit. Most amps that run one type will run the other, so you can experiment with both to get the response that you want out of your volume knob. It’s a lot like adjusting the gain of the power amp itself

[@johnmorrison5502]

But what type of paint was on the amp? That’s a huge difference in sound only the most experienced would notice.

[@sski]

Don't forget the 'tone wood' amp head cabinet construction! It matters!.... lol, I can't believe I just typed that.

[@allanallan4791]

Tome paint adds 20% more tone to the amp aha

[@sski]

@@allanallan4791 LOL

... well actually there is a study about "influences of color on the loudness judgement". Hearing is a psychoacoustic phenomenon. So while there will not be a measureable difference, people will tend to think your amp is up to 15% percent louder only because the amp is red, according to this study of the tum. This is how stupid we humans are. Google that study, that is ultra interesting

[@sski]

@ Makes absolute sense.

[@crottedepingouin]

i've always seen the tube change as a way to cutomize your amp, a way to fix the little things you want to improve about your amp. today, glenn made me question everything, i was already ready to come up with criticism but this video answers all questions and doubts about the matter. this is the best spectre sound video so far (and i've been subscribed for a while). great job glenn, and thank you. changing people's mind on the internet is not an easy thing!

[@SpectreSoundStudios]

Thanks, man! I finally had the chance to put some time in on a video & this was the result...

[@crottedepingouin]

@@SpectreSoundStudios the fact that you put time into this really shows, what really works for me is how you anticipated all the responses and questions you might have gotten (i was ready for the vintage/clean amp one!)

[@BassRacerx]

yeah I think build quality and life cycle are probably the things to look for in tubes. especially if your gigging with a tube amp.

[@yaniv-nos-tubes]

it's easy when they are idiots

[@Jake4059]

An incredible eye-opener. As of now, on this day, i solemnly swear to never smell another cork again. Thanks for showing me the light. Furthermore, the mic placement example really deserved it's own mini video demonstration because it's a very valuable piece of recording knowledge that has a much more dramatic effect than id ever thought. This is a great video. Just Excellent. Loved the null comparisons as well. That told me everything.

[@transistorradiorecords3661]

I think the JJ sounded special, kind of magical unicorn dust sound. Warmer yet blissful. Of course I have special Tube speakers.

[@LuisVasquezMusic]

I was expecting these results but it still amazed me how there's basically NO FRIKING DIFFERENCE. At least not a very noticeable one, specially in a mix. If you want to be picky go ahead and use different tubes but in reality no one in a audience will notice.

[@BrianGay57]

No one in the audience will notice much of anything. They sure won’t be able to tell you’re running your NOS Mullards and just tweaked the bias hotter! 😜

[@gilbertspader7974]

I once stacked a wall of cabinets to block wind at a gig . Didn't hook them to anything and most people said the new speakers sounded great .

[@HALman1973]

But...but...they feeeel different man. ;-)

[@russellzauner]

when I ask for tubes, I ask for *quality* tubes rather than some other aspect from some manufacturer or tube sortin company because I want tubes that work to spec not fucking magic beans. your #1 defense against bullshit is not just watching teardowns and tests but actually understanding a little of the thing being torn down and tested.

[@LuisVasquezMusic]

I mean, it's used as a justification because it's true. Apply it to tubes, gear, ability, etc. They just care about being entertained and we as musicians should concentrate on that. Entertain people, make the best music we can and stop caring about the things that will not accomplish those things.

[@edcook7150]

Bottom line, Glenn might take heat for this test, but he is just trying to save us some money. Thumbs up.

[@maulalex08]

I feel like you just made an unintentional pun

[@themicrotonalguitarist]

lol

[@realtruenorth]

Its funny because I changed my tubes because I suspected they were kinda weak. Sure enough a fresh set sounded great. More of everything. Tubes can get old and weak and still work and might drive you crazy while you're trying to figure out if something sounds different. Tube testers us what we should buy.

[@rocketsalad]

I think the only thing Glenn took for this test was a handful of Adderall before he started recording

[@Christopherjazzcat]

Nice test. Good to see someone actually use the scientific method. The responsiveness where a tube starts to move from clean to distorted is what many players mean by feel. Your test seems in line with this. It's certainly what I'm looking for when I'm dealing in an amp. "Feel" also gets used to refer to "time feel" as in how a player moves around their timing expressively. This seems to be more pronounced in certain genres.

[@jimmoss9584]

The bias is setup in the local feedback resistors, called self biasing, in small signal tubes like the one we are talking about. The frequency response is also a function of the tube resistors and caps. None of this will change if the circuit was properly designed. The idea in good design is to make the resistor bias and frequency performance dependent on the the local circuit itself and therefore be immune to variations in tube construction. The OPEN LOOP circuit which has none of these protections. Those will depend on the tube for the circuit's performance. (That is what a college education in electronic engineering will get you. I am an EE, Musician, Studio Owner, Equipment Designer.) So how swamped (technical term) the circuit is will determine the performance as outlined above. Changing a 12AX7 with another 12AX7 of another brand, in a properly designed circuit, will make no difference at all. The proper designed circuit depends very little on the actual tube other than for gain. You might be thinking of POWER output tubes with their ability to have a pot for the bias setting. There are a family of 9 pin tubes in the 12 - - 7 tubes. These are optimized for either Voltage Grain or Power Drive capability. The 12AX7 is one of the worst in the family. These were made for cheap 5 tube AM radios. These can cut back on the number of tubes that are needed in the AM radio. This is called Economics. The 12AX7 driving a high Z load will still have a lot of distortion, but lots of gain. If you replace that 12AX7 with a lower gain tube with a lot of drive capability like the 12AU7 then since this tube can drive more power into it's load without distortion, but with less gain, this will make the quality will go up and the loudness go down. Loudness and Tone is all about the circuit around the tube. This can be tested with an Analog Signal Analyzer. So the range of tube designs were meant to address these different requirements. You might want to examane the Decoupling circuits of each amp section. I updated mixing consoles by adding bigger Decoupling Caps. I checked the console with a Kick Drum Sample. This was causing the input of one channel to drive all the channels into saturation. These were cheap performance mixers.

[@Hellseeker1]

Glenn's like Santa with this one, saving everyone money for Holiday's. Make sure to re-bias, double check that shiz.

[@portlandshomlessproblem1728]

Cathode bias for the win, just throw a new set in and check that is within proper range. No rebiasing necessary unless your amp or tubes are bad

[@DaveWestGuitar]

I hate paying for the tech to do the bias, but it is crucial.

[@Yupppi]

Especially if your amp is made on a different continent or country. The amp builder has no idea what the actual reading in the wall voltage is in your country versus what the official rating is. They just try to get close to the official rating and perhaps adjust a bit for the variance they've been reported with, and if an american builder sells an amp to europe, every country is different even if they're generally in the same range so you just get an average guess. By correctly biasing an amp you ensure that it sounds like the builder intended it to sound like. Funnily enough, a change of tubes might actually get the bias closer.

[@123lowp]

Guys, just turn the amp upside down and play riffs. Turn the bias knob until it sounds how you want. Then check the voltage and current and make sure it is within the acceptable range so you don't blow your tubes up.

[@h1de]

I can already tell you there's gonna be more "wah wah wah!" about this video than a Metallica solo. 🤣 Great video Glenn.

[@michaelsnydermusic]

Thank you Glenn! I can’t imagine how long this took! The funny thing is how much a slight mic placement can change tone yet people would rather go on and on about tubes.

[@TheDynamicsDepartment]

Thanks for making this! I'm super glad I found this before going down the rabbit hole! You saved me much time and money!

[@iantaylor4115]

I thought it was Fairy tears, Unicorn Farts, and Dragon's breath? Do you mean psychoacoustics and moods change the human's perception? Thanks for doing this, I've been looking forward to this video!

[@bmcash3411]

Finally, someone who actually did a proper scientific study on tubes; only variable was the tubes and everything remained constant. Bravo, sir.

[@fransvanhelvoort1083]

Absolute great to do the null tests! It makes the statement very clear. Just great

[@miyannaable]

Wow - just WOW!! I know it's been a year since you put this out, but I just learned a lot!! I've been using GE tubes from the 60's and 70's for years in my preamps (ART and Bellari single-tube ones, and Laney and Mesa-Boogie with 2 tubes each). I became very curious after I couldn't get the Laney IRT Pulse safely apart (as I can with the others) in order to switch out the tubes. Then I shrugged and plugged it in, and it sounds AMAZING. Hence the search that led me here. Thank you so much!!

[@vaibhavahujate]

Yesss. I've been waiting for this video since the Klark Technik Review. It amazes how people (even smart ones) want to validate their purchases without considerable evidance. I hope you'll release the tracks to those so I can show this at school to all my classmates and teachers as well who might say something about KZbin not being enough due to its compression algorithm.

[@guitar19971]

I was surprised by these results. I was expecting that changing the valves would make a very small difference but I wasn’t expecting how little difference it actually made. Great video Glenn!

[@sk8ter409]

love how easy it is too tell apart the people who wasted money & the people you saved money from this test 😂 😂

[@shanebuzzell1889]

Exactly! I learned this when I realized my blackstar had el34 Vs 6l6. I've had alot of different amps over the last 20 years. I think it's the circuit,pickups and speaker personally

[@nathancloud6344]

What a great way to display tonal difference in a complete band mix. Stunning!!!

[@TheWheezinHeathen]

Everything else aside, that snare sound during the first power tube comparison is probably the best I've ever heard, nicely done sir ^_^

[@flowryan5829]

Exactly my thoughts

[@thesilentu]

Not a fan with too much reverb on the snare...but it sounds gorgeous

[@mikescotch8894]

Awesome snare!!!👍😂

[@alexander_noren]

reminded me the snare sound on Metallica "Black Album"

[@deadsky13]

This is THE most thorough application of the scientific method outside of a formal scientific or academic setting. I'm sending this to my brother who's an educator. This needs to be shown to kids in middle school!

[@drkslider1182]

Glenn you just pissed off every forum amp gurus. I love how honest you are! I’m starting to think my old tubes were shot.

[@chasesrc]

Great comparison video, that totally shed some light for me. Thank you!

[@davidfuller581]

So, I've mentioned it to you before: the differences I've noticed, doing the same tests as you, found no more than +/-2dB of difference. It's present, but it's not super game changing the way changing the speaker would be.

[@dionr1168]

In before the "Glenn, you cheated by using a reamp box and an impulse response!" Those comments should be automatically nominated for "Butthurt of the Week".

[@denverrandy7143]

Man,those guys are some stellar players...I'd love to get my hands on a copy of those songs.🤘👍Great content as usual Glenn!!!

[@TheSennaj]

First video I've seen of you in a while, I'm blown away by your shape man, nice work!

[@ericrhill]

This was incredibly informative Glenn. I blindly believed the tube logic for years because that's what I was taught. But armed with this new information backed by reputable testing I see how wrong I was. If nothing else I now know if the tubes in my amp start to fail then the stock chinese ones I pulled out of it will make perfectly acceptable replacements. Thanks for saving me money that I can put towards something more beneficial!

[@BrianGay57]

Yeah, I’m glad I never went totally off the deep end chasing tone. Speakers and pedals were my main thing, but I’m set there now.

[@bradmiddleton412]

I have a Joyo Zombie and been considering changing the valve in it to see how it would effect how it sounds. This video has been a help!

[@nOT_sURE08]

I too have been playing on a JOYO Zombie for a few months now. After about two months of taking the thing through its paces, it started to sound weak. I replaced the tube and that seemed to perk it right up. I dunno if my particular unit simply had a faulty tube or if I just overused the heck out of it. It's been good ever since though.

[@willcresson8776]

@@nOT_sURE08 its more so that the tubes they come with just... suck. Ive got a Joyo Firebrand (fireball?) and swapping out the no name tube for a basic Tung Sol made a huge difference in performance. Swapping between the tungsol and a JJ I had laying around, however, did not make a significant difference.

[@MuttleyGameTube]

Thanks Glenn, professional as usual, the Synergy example explains everything. I could hear some small changes but honestly, moving an EQ or mic will do much more difference than swapping tubes, but of course "Tubes fanatic" will always have something to say!!!

[@SpectreSoundStudios]

Glad you made it to the synergy part. Most didn’t before freaking out.

[@joshuaandtheruins8580]

Thank you so, so much for this. You had me at "scientific method," and I really appreciate your thoroughness and openness with the results. I am not a metal guy much anymore (though I still follow your channel), and now I play a Danelectro guitar clean through an AC-15. Earlier this year, I switched out some stock, microphonic tubes for JJs and thought I noticed a difference: mostly in it getting a little hotter relative to the same volume levels, and breaking up a little sooner, and dirtier. But I couldn't really tell what was going on, and I certainly didn't notice some drastic change in tone or clarity like everyone said I would. I had also already thrown away the microphonic ones, which I lamented because I wanted to do a reamp experiment exactly like this. Your results were consistent with my experience with the switch to JJs, and overall the amp sounds pretty much the same as it did before--just a touch louder, and now the whole thing doesn't rattle when I play a low Eb. I thoroughly appreciate this scientific experiment. Thank you again.

[@SpectreSoundStudios]

I’m glad at least ONE guitar player appreciates science!

[@pipelineaudio]

In before the lynching

[@romannavarro620]

“I changed my tubes and I can hear a difference!” - Patrick Star

[@bradwengranowski4995]

Glen, own a Mesa road king ll and I agree, when switching the progressive linkage on the back of the amp between EL34 and 6L6. The change in sound is so subtle its own it’s not even worth arguing about. In a full metal mix, you’d never be able to tell. Just finishing up my final touches on my oldies but baddies entry. Can’t wait to get it finished. Cheers from Surrey BC.

[@DavidAndrewsPEC]

I get a warm glow when Glenn does science. When a recording engineer can grasp the scientific method and get what the results mean, nobody has an excuse to ignore it. This does indeed bust the whole tube myth. Right up the arse. With a dry cactus! Nice one, Glenn!

[@michaelstevenfriedlander4583]

He's absolutely wrong, and there is no myth.

[@DavidAndrewsPEC]

@@michaelstevenfriedlander4583 🤣🤣🤣 Yes, there is a myth. And it is still being maintained by willing believers.

[@GCKelloch]

Don't you hear the differences in the null clips? Surprisingly different results when he compared different tubes.

[@DavidAndrewsPEC]

​@@GCKelloch 🤦🤦🤦🤦🤦 Not an objective measure. What bit of scientific observation is to complex for you to understand?!

[@gordontubbs]

NOS tubes, otherwise known as "New Old Stock," do in fact have a slight difference in the gain structure regarding one's EGO and upper harmonic content of their amp snobbery.

[@XlouietheflyX]

BUT BRO YOU NEED TO GET THE JAN PHILLIPS NOS 5751, THE JJ 5751 IS REALLY BRITTLE BY COMPARISON

[@BassRacerx]

I see what you did there, but one time I changed my tubes and it sounded like Jesus was whispering in my ears. That was back in nineteen ninety eight when the undertaker threw mankind off hеll in a cell, and plummeted sixteen feet through an announcer's table.

[@yaniv-nos-tubes]

@@XlouietheflyX jj can't compare to any nos it's without treble

[@yaniv-nos-tubes]

try to hear one

[@-Kal-]

I think we can settle the debate. We recruit someone with synesthesia and ask them if the letters RCA sound better than the letters JJ.

[@horse_dog]

I’ve been waiting for this!

[@fernandonichols7168]

Snap!

[@TheGhostfaceKLR]

Thanks for doing a fairly scientific comparison like this. I've been playing guitar for about 40 years. I've also been a scientist and electrical engineer for a bit over 25 years. For every proper test like this, there are 10,000 internet posts reinforcing all the guitar amp myths that have evolved, and it's hard to not be influenced by them. The comparison between EL34 and 6L6 once again reminded me that it's amp design, not tube choice that really dictates how an amp sounds. I have however noted a change in a particular amp of mine when I went from EL34 to KT88. But that's a rather significant change. I found I had trouble with the amp reproducing too much low-end with the KT88s.

[@XChristianNoirX]

I experienced this in a JCM800.

[@Superunknown2014]

Same here with KT88s and a JCM800.

[@francismcfadden3305]

The phase flip part of the test was some science right there man.

[@RSully2010]

Excellent work Glenn, thanks for the work you put into this. I'd like to see you have your own Mythbusters for musicians series. Love your channel

[@SpectreSoundStudios]

That's a great idea!

[@thebasementfilmgroup]

Biggest myth of all "Don't worry guys - we can fix it in the mix!!" BULLSHIT!!!!

[@metalhead83192]

i DO play with feeling. "pissed off/angsty rage" is a feeling. oh, also, changing your tubes will have about as much effect as changing which outlet your bass player is putting the butter knife in...again. wanna change your tone? try the dials on the front of the amp.

[@sski]

buh-BLAM! Great comment. Especially the last line.

[@pyroman6000]

Wait- you mean I'm supposed to USE those???

[@ffxiiangel]

Nah, man. You change your tone when you move the Metal Zone from the front of your amp to the Effects Loop!

[@cordero6960]

bass player are dumb but Tone Expert are even more dumb

[@thesollylama130]

As a bass player I always thought it was a fork I was supposed to put in the outlet. Jeez, no wonder my tone has been terrible.

[@AviRochester]

So so much talk about vacuum tubes but I have not seen anyone explain what speakers are needed for them. Speakers also play an important role, but we are not talking about specific models for this. Thanks for the invested and beautiful video.

[@jasonstewart9752]

Thank you for this vid! The null tests were convincing. You saved me some $$$. Appreciate it!

[@uselessminionz8860]

Can we just all agree that the snare sound in these clips was the real hero. It's so good

[@GeeMorno]

That was a pretty Kraken snare thought hey....

[@seantierson2633]

Next step: collab with CSGuitars. He can talk about what the actual differences between different tubes and why it doesn't matter 😂

[@driesvanoosten4417]

I have to say that I'm not that impressed by CSG's technical expertise.

[@mikestckl6939]

better collab with brad the guitologist , he can REALLY tell you how and why it doesnt matter

[@frosty6845]

@@mikestckl6939 you mean before it after he subjects you to ramblings about how he thinks climate change is real

[@johndogwater]

This is reassuring, when the Mullards in my little vintage amps go I wont bother hunting for more. Thanks for putting the work in. Great video.

[@somethingredbird]

Well done Glenn! Thanks for taking the effort to do this right.

[@tsunamijin]

This is quite a brilliant test. I would love to see more of these. On topic, imagine if musicians focused more time and money on Songcraft and skill development instead of a small adjustable in their gear. Just imagine the records that could be made. One can dream.

[@eddiesigerexperience9803]

Haha so true, Yet I’m still here

[@JaggerSan]

I like the null test results, I have tube swapped to modify the tone of my amp admittedly a Mesa dual rec sounds and reacts much the same, biggest difference was the poweramp threshold between el34s vs 6l6s I preferred the bass response on the 6l6 in that amp. Interesting video though 👍🏻

[@salemthekidmusic]

Wasn't expecting to hear much of a pronounced difference, but it's definitely there. The mullards and electro harmonix seemed to have less high end, and volume when compared to the JJ's and stock joyos. Eye's closed listening on neumann kh120's. I switched to my macbook pro speakers and still heard the difference. Interesting stuff Glen! Thanks!

[@td7426]

I'm glad that my ears are still good enough to hear the tonal differences of all of my preamp and Poweramp tubes. The feel factor is also a very big thing.

[@lordvermintide4441]

Finally someone did this test the way I've always wanted to. Glenn has been rather unscientific in some of his previous "scientific method" videos but this one did everything I can think of right. Good show. Conclusion: There IS a difference, but it's mostly level, not tone. Nowhere near the world-changing difference forums make it out to be, but it's not TOTALLY untrue- it's just not what these cork sniffers say it is.

[@DM-rc4yu]

@@lurch789 So in reality, tubes don't make a difference. Gotcha.

[@tomscioscia9869]

The null tests sound like a lot of the difference is in the highs, which is admittedly what I'm usually trying to change.

[@nikumeru]

I bet you tubes made 1 week apart at the same factory will have such small variances.

[@SpectreSoundStudios]

It’s right in the crunch.

[@Souchirouu]

The point is that it's not worth the investment and you're better off investing in other parts of your signal chain to get the result you want. - Get different strings for your guitar. - Get different pick-ups for your guitar. - Use a different pick. - Buy or upgrade a cab with speakers aimed at the kinda sound you want. - Invest time into practice instead of playing the lottery.

[@tomscioscia9869]

@@nikumeru, most certainly from the Shuguang factory. I generally like their tubes but I have a bunch of them that do sound different.

[@tomscioscia9869]

@@SpectreSoundStudios, yeah, I mostly play dirty and sometimes the difference I'm looking for is sparkle vs no sparkle. In an amp that doesn't have a presence control that difference can be nice. I tend to find that the New Sensor EHX-branded tubes tend to lack any sparkle at all while the other New Sensor tubes (Sovtek, Mullard, Tung-Sol, Svetlana) tend to be better with that. But, basically, your null tests pretty much confirmed what I thought about the differences being small but still there and that the JJ tubes are simply louder (since they're the closest to the actual published 12AX7 spec). The big difference is that some companies throw a bunch of components inside a glass tube and slap a label on it while that label may not mean what they think it means.

[@Likely_Alucard]

Interesting…. I am not a musician or anything of that sort. I have known many. But I saw this video while researching tubes. I am looking to pickup a class AB hybrid amp just for fun, and I have definitely seen the discussion of changing tubes changes sound…. Informative video, and very useful!

[@claytongouin5605]

You really out did yourself, Glenn. This was a terrific video, and I am glad you pointed out the 'tone' changes are merely volume differences. Also, I am glad you mentioned changing speakers or mics or mic positions. These are all overlooked aspects of tone, and if guitarists spent half as much time worrying about guitars, amps, pickups, or pedals, and more time considering the less sexy speaker and cabinet combo they used, we'd probably have better information on the forums!

[@cigilovic]

Glenn, you are a legend man!!! We guitarists should start comparing things by just saying "it's slightly different!" instead of acting like we have found the secret component to our guitar tones! From my experience, guitarists are the number 1 myth creators in the universe. You have responded to them in the best possible way :) Excellent stuff!!! PS: If I had to go for a myth creation session, I would preach SHUGUANG! Because it's difficult to pronounce :) Cheers Osman

[@matttaylor1449]

It's simply pronounced "shoe hwung" two words not one.

[@cigilovic]

@@matttaylor1449 You messed up my mojo myth

[@blakecurtis7809]

We need a cork sniffers shirt Glenn. "Beware of the cork sniffers" or something along those lines.

[@ciddax754]

Thanks a lot for this test. I found it very interesting, that I perceived the louder tubes in the Joyo banTamP as having more highs. Good to know that my ears do trick me in perceiving this. And that convinces me even more, to compare always with the same level. In my opionon is the 'big' difference, the different gain structures of the preamp tubes. It's not huge but it's there, as we could hear with the fender.

[@rhmm96]

This was really interesting! Kudos Glenn!

[@mojoemurphy]

I was shocked how different the different tubes sounded in the Joyo. Then Glenn mentioned it was a level difference and my mind was blown. I listened to it again and it seems when the volume dropped down I associated more of the bass tone with the guitars. Kind of blended them together. Wild

[@GCKelloch]

If it was only output, the null clips could be adjusted so there would be absolute silence.

[@pauliusmscichauskas558]

Next step in this "Does it make a difference" guitarist myth journey: Cab speaker break-in. Null test that stuff!

[@SpectreSoundStudios]

Yes!!! Definitely doing that!!

[@mkenny17]

@@SpectreSoundStudios please do that glenn :D that would be a very interesting video and information.

[@TheOziBattler]

Add studio monitor breakin test to that...my feeling is that all you are breaking in is your ears.

[@XlouietheflyX]

I would agree with the stories about a difference, but only with V30s. I didn't notice a difference at all really with H75 Creambacks. I suspect it is due to the way that the frequency profile of the V30 is impacted by the stiffness of the cone due to the stiff doping used on the speaker, and when it breaks down a bit that changes. I didn't notice a change with the H75s but their frequency response is different. I hated the V30s until I broke them in

[@Pauligrinder]

That'd be really cool to null test. But I'm pretty damned sure my V30's sound better after breaking in, don't know about other speaker types though.

[@ivyhallquist3159]

Glenn, you sure do have an amazing bunch of musicians that you get to play on these demo tracks!

[@pennabis]

great work! I do appreciate the scientific method applied here. this is going to help save a lot of time and energy.

[@felidae1994]

Since good recording = good mix, do you use reference tracks for recording too? Also what about fearless review for somekinda drum samples software?

[@BlueBarrier782]

The null test was such an excellent idea. This should be applied FAR more often in other comparison videos for gear.

[@DM-rc4yu]

@@lurch789 Either that, or it's bullshit.

[@MichaelMoore-od4jz]

Great test love all the great info

[@mimmo2977]

simply, an excellent video - subscribed ! thank you

[@SpectreSoundStudios]

Glad you enjoyed it!

[@BeanDogStudios]

So you got the same result as I did. A bit of a difference in gain. Cool.

[@JoeontheInside]

I mean, the null tests didn't completely null out the sounds on some tests, there was still some noise there, that means it *is* objectively changing the tone, but I would agree that it's not very much at all.

[@ameer_saban]

Are the null sounds a result of volume difference? Because the actual tones sounded exactly the same.

[@terminalvelocity4858]

@@ameer_saban necro response, but no, as Glenn said in the video the ONLY change was the tubes!

[@mvwoon]

I could hear pretty big differences!

[@ChrisCGuitars]

Fantastic video, really informative... I need a retube because my power tubes are failing. Glad to know I don't need to break the bank to get it done

[@jasoncrump1886]

Appreciate this video. Great job and great info. 👍

[@DragonboltBlastter]

Great video Glenn! By the way, does this evidence (portrayed in the video) also apply for audio interface preamps? (stuff like Focusrite, Steinberg/Yamaha D-pre, Presonus XMASS etc.). Where the volume & distortion cause the differene and not the frequency signature? Cause i always hear from fellow recording engineers that the preamps ''sound different'' (talking about the audio interface preamps that DON'T emulate some kind of ''coloured'' hardware stuff like Focusrite, Steinberg/Yamaha D-pre etc. etc.)

[@josearaujo8616]

Applies to mics and pickups also.. principle is the same. Think of them like an old TV antena. The better the antena is the more faithfull the image on your tv will be up to a point, if you start moving the antena or use crap antenas, what you see on TV is not what is being transmitted. You can always degrade the signal, but you can't ever recover lost information and frequencies. Faithfull amps (tubes or solid) or antenas for sound are not that expensive...

[@nickontiveros1016]

This is exactly my experience with tube swapping. I swapped out a Shuguang 12AX7 for several variants of 12AX7 and heard nothing, but percieved a gain/breakup difference when I substituted a lower-gain Sovtek 5751. Still sounds like the same amp.

[@thesollylama130]

Hey I did the exact same test myself with an Orange Micro Terror. I swapped the stock 12ax7 for a JJ 5751 and there was a drop in raw gain, but probably within the range of what the gain knob could produce anyway. Then I swapped in a Tung Sol 12ax7 and it was a bit louder than the stock at the same volume knob setting, but tone was basically identical. Certainly no huge change in sound like a lot of 'experts' would have you believe. Cheers!

[@Danu625]

Same. I went from a Tung Sol 12AX7 to a JJ 5751 in the PI and it dipped the gain just enough so that I could push the whole pre a bit harder for the same output, resulting in a more pleasing sound. You can't just dismiss level changes as irrelevant to tone. The whole point of some of these options is how they function in the gain staging of the preamp and headroom and output factor are fundamental elements in that.

[@themightymcb7310]

I've never noticed tonal differences between tube sets that I've used, but I have noticed subtle changes in the gain structure. I swapped the stock tubes in my 6505MH with the JJ low gain set, and honestly all that it changed is that I could actually use the clean channel. The gain channel sounded identical, except that I could turn the knob a bit higher before bottoming out the gain levels.

[@applesawz4u]

you sir do all of us a great service. salute.

[@AndrienQ]

As a somewhat reformed tone chaser, I can say that the shifts are only very subtle but still noticeable. Not something to be pined after or revered. I miss my Tweaker 88, but the sound I get with my Headrush Gigboard is probably better and with a much smaller setup

[@vyx019mhknot6]

Thank you so much for doing this video! I had a feeling it hardly had any real effect on tone, but so many articles kept suggesting otherwise and I needed something substantial to go by. Though now I'm curious to ask whether or not pricier tubes are worth their price as far as shelf life is concerned.

[@riffwizzard]

Great video. There's so much WOO with tube purists. I never really noticed a massive difference in preamp tubes in any of my amps. BUT for a couple, power tubes were a very big factor, and really use case-specific. I've got a 200-watt Matamp style head, which can handle anything from EL84s up to KT100s. I play loud and I like my tone just one the edge of breakup before hitting the front-end with fuzz. For this, there's a huge change between EL34 and KT88 tubes, and it's not just perceived volume; response and low-end when you get into power tube distortion is night and day. But my case is soooo the exception and not the rule. My advice: get moderately-priced preamp tubes that are available in quantity and rated as reliable, and treat the power tubes the same way, with the exception of a bias from a competent tech. You'll have the best tone and reliability you're gonna get out of your amp.

[@squidcaps4308]

I'm so glad to see null testing finally making it into Glenn's arsenal. Level matching of course will affect the whole thing.. The proper way to do it is to adjust the levels in post to produce as small residual as possible. That is the actual change in tone. edit: overall, i found more changes than i expected, of course, they were roughly in the magnitudes i expected. My background is in EE and i should be able to design a 5150 from the scratch (should be in theory.. practice might be different... ) and the difference really is in the circuit design, its topology, where it has filters (accidental or deliberate), what compromises had to be made and so on. Transducers are still the biggest variable and the worst piece of kit in the chain. Mics and speakers are.. lightyears behind electronics, specially solid state electronics. If you can get the sound from a solid state, even if it is minutely off, you will have that sound forever and can reproduce it much easier. Tubes are great but they are not the only way to get that sound.. Blind testing, null testing etc are very good tools to remove our own pre-dispositions from the equation. You might be really surprised for the results.. and may be able to do it in the future with minimal investing and without any equipment lottery where you buy new things trying to find something you don't know what it is yet. It is like playing darts in the dark. Other things that don't matter: tonewood, power conditioners (unless you actually have actual issues), cables, converter preamps, samplerate above 44.1k, dynamic range above 16bit in playback, above 20bits in capture, noise floor below 80dB in most cases, THD below 0.5% (human perception is around 3-5%), component burn-in time, system synergy where everything affects everything else etc etc etc.

[@Aaezil]

I mean cheap guitar cables 100% make a sonic difference compared to higher end ones. Easy and obvious to test (they even have directionality). For like balanced cables they do not make a difference at all though as long as put together correctly.

[@Pauligrinder]

@@Aaezil I disagree about the cables - yeah, the signal can be weakened by the resistance of the cable if it's really long and thin (and I don't even know what the ratio is where you'd start to notice it), but otherwise I'd say any difference will be caused by external interference or placebo.

[@jaycer71]

One guy in the back of the room is standing with his arms crossed saying, "Yeah, I hear the difference."

[@zandig666]

Thanks bud !! I've been investigating a lower gain tube for my marshall but I saw your vid pop up !!!!!!!!

[@thommyers3080]

Thanks so providing true tests and information. I ,more than likely, need to change the tubes in my amp because I forgot to turn it off for a few days a couple times. It definitely doesn't sound like UT used to after that

[@firstclasspassenger]

The title had me like “Nooo, he’s about to unravel my whole reasoning behind Blackstar’s ‘TrueValvePower’ feature set”.. but as a AES Audio Specialist, I have both doubts & suspicions about voltage sag and SolidState\Tube hybrid tech

[@CyberChrist]

WTF is even ‘TrueValvePower’ ? :P

[@zaldinor9]

@@CyberChrist Its a patented technology which helps emulate tubes within the solid state domain. It does this by altering the frequency response depending onthe dynamic range not just altering the frequency and dynamic response separately.

[@haydenkayne]

@@zaldinor9 I have a id30tvp, that knob is pretty effective in changing the tone for sure. the boss nextone does something similar. the blackstar is a great little amp for the money.

[@CyberChrist]

@@zaldinor9 Thx. Peavey's TransTube did emulate tubes quite well aeons ago ^^

[@evilgremlin]

​@@zaldinor9 I've read an article on perfect emulation of tube overdrive using a concept of "virtual scalable diode", but with any opamps and no tuning required whatsoever (unlike with plain JFETs). Difference from original was the same as in any two units, due to 5% component tolerances

[@lastboxofsparklers]

Dude, that's not what a "fixed bias amp" means. It still needs to be biased correctly for the tubes you use.

[@driesvanoosten4417]

Although it is not going to be as big of a deal as people claim, or put differently: power tubes usually aren't biased properly by the amp manifacturer anyway.

[@lastboxofsparklers]

@@driesvanoosten4417 if you've ever had a power tube over heat I'm sure you know it sort of does matter?

[@jordynorm8212]

Excellent video Gelnn! bravo on the methodology, the null tests were perfect for this and clearly show tubes do almost shit in changing the tone. We've all been lied to! On another note, it's interesting because as humans we seem to have programmed this "Tone Change" into many amp modelling softwares too, on my Axe FX II the tone drastically changes by only changing the virtual "power tubes" in an amp. I guess it's been programmed for our expectations rather than reality! Same with GT-1000 by the way.

[@chrishastings]

Great Vid Glenn!..... love the scientific method! :)

[@tomscioscia9869]

I'm actually shocked that there was ANY difference at all between the "no label" and Shuguang tubes in the 5150 since the "no label" tubes are Shuguangs these days.

[@kainagami]

Gearslutz has ads on KZbin now...

[@montychristo86]

Let them all catch HIV and die of their own arrogance. I couldn’t care less.

[@kainagami]

@@montychristo86 indeed

[@antonwilding9744]

Wow thats interesting , i thought the impact of other tubes would be bigger . Thanks alot Glenn for busting this myth \m/ .

[@randybach4581]

Just last week I re-tubed both my 59 Bassman re-issue and my 69 Fender Super Reverb with JJ’s… I asked the tech if I should get “better” tubes and he said “expensive or cheap, the tubes make no difference in tone at all”… thankfully I listened to him and saved a bunch of $$$… I feel better now after watching this 😊

[@thekramer1097]

18:40 That's the never ending battle. Wise words