Just How Loud Is A 100 Watt Marshall When Turned All The Way Up? 

Just a side note, some of these dB measuring phone apps are limited by what the phones own microphone can pickup. If 112dB is it's limit, then that all it will ever show.

The threshold of discomfort is approximately 110 db, actual pain happens closer to 130 db. Nit picking for sure but a cranked Marshall is definitely loud but not painful. A 747 at takeoff can be extremely loud at levels approaching 140 db, obviously the volume is based on distance and which engine the plane is equipped with.

That was really great

The fundamental reason it sounds loud is because of the hard surface walls. A little getto blaster in a sports hall will fill it.it's bouncing everywhere

Block walls are very soundproof, it’s the roof that lets the sound escape. Our band practiced in a block garage for years. Once we properly insulated the roof, you could barely hear anything outside. No matter how loud we played.

The detection limit of your phone is probably 112 dB.

Well an arena full of em will kill your hearing. ACDC in 82’ was a monster! It actually made me nervous. Cliffs bass was pounding through my chest, i had to actually hit myself to make sure my heart Rythym was beating on its own beat & not his. Motorhead, 80’s Megadeth some seriously loud chit live

I love the "shock and awe" in modern videos of cranked Marshall stacks when this was part of a standard rig for any successful local UK rock band back when I started playing in the mid '70s! If you didn't already have a rig like this (or, better still, a proper stack with 2 cabs), it was something you aimed to get before long. Fresh out of high school, I was lucky enough to practise for my first gig at the rehearsal space of one of the main local bands here on the Isle of Wight - a barn packed with a wall of Marshall stacks! No earplugs of course (we didn't even consider using them back then...), but it was a wonderful way to start! Nothing I've played in recent years has ever really compared. 😉

Iiiiiiii like it!!!!!!! Yep. Even at 70 years old I Liiiiiiiiike it. I remember as a kid, 20, I had an Ampeg V4 100W that I would turn it up all the way in a small room and just blast away for hours. Of course I wear hearing aids now. You’re going to have a great studio soon Ole Buddy ❤️

I heard that all Marshall amps have a secret mode to turn up to 11, includes a free smoke effect too.

I still have mine! Rarely use it. It's so damn loud, heavy and bulky. It's a statement of how rock n roll used to be.

This is what my parents say my guitar sounds like at 0.1% volume

I tell you, that's not the room I'd want to be in with that level of volume. Concrete and cinder block??! Yikes! Then again, these were built for venues like Madison Square Garden so, yeah, it's loud, lol.

Keep in mind that this is not for home use. NO HOME USE. This is a beast for war and we all can see that it is able to do!!!

It is so unbelievably loud I couldn’t bear to jam with a guy who has one and insisted on playing at full volume in his house. He was talented but that amount of pain to use that amp was insane.

It's too loud and yes, I'm too old. Having said that, when I was young it was still TOO LOUD!

I’m shocked at how good Bill Burr is on guitar! 😂

Amps don't necessarily get louder the more you turn them up. They have a thing I know as headroom, where after a point they just won't get louder. CSG Guitars has a great video on how this works. Its the reason I think (short of the phone not being able to go above 112) the meter is peaking.

I'm a total Marshall fan but my old mesa boogie triple rectifier would shatter the concrete blocks i mean that amp was louder than any other I have came in contact with. 🎸

You guys ought to do this for other classic British amps also. Like for example, one of the few shows I ever wore ear protection to see was Saxon who I think were running all Laney amps at the time. That show was so loud I was more feeling the music through my entire skeleton than actually “hearing” it 😂 (Those guys were very cool after the show, too, they took a lot of time to meet the fans, shake hands & sign autographs and all)

I have a JCM2000 DSL 50 the sweet spot for the volume knob on Ultra Gain 1 is at around 6 that's where it opens up to full but before it starts to 'flub'. I play metal so have the Gain at around 6-7. Modern reactive attenuators are the best thing for guitar in the past 20 years.

Marshall sounds absolutely awesome 😎 🤘🏻

I recently picked up a Stereo EL 34 100/100. Ran the power amp at 100 percent & JMP-1 at 5 or 7 into 2 quads, and walked outside my house with a wireless system just to hear what the neighbours were listening to. It was at this point I realised I will need to practice more or get better lessons. My poor neighbours. 🤣🤣 The ground was shaking & so were the cats! (Don't worry I had them locked in the front room at the other end of the house.)

I figure the phone call went something like this “Hey Paul, the walls and roof are done, you need to come over, I have to show you something!” - “I don’t have time rn, I’m recording” - “I bought a 100W Marshall, wanna try it?” - “I’m on my way” …

I've had one of these amps for the last 22 years. I don't know what I was thinking...too loud and powerful for my needs. It's been sitting in my basement forever with little use so it still looks almost brand new. I use mostly combo amps these days. I've been thinking about selling it for years but never seem to go through with it...I think I just like to look at it when I'm down there...like an art piece or something lol.

I think is this DSL100 have a problems. Because normal DSL 100, put in1960AV, with new tubes, have 124-126 dB measuring in 1m.

Do this with a 2204 or 4010 50 watt, the ones I’ve had, the master from 7 to 10 literally doubled in volume, like a rabid dog. This amp sounds really good, is it an early UK made DSL? Also, would you know which speakers are in the cabinet(65,70,75’s?)

I have an '80s Marshall JCM 800 100 watt half-stack. It's so loud, it ridiculous!

It should put out 123 dB with two cabs. 112 doesn't seem right, unless the amp is faulty. I noticed some hum.

Can't tell you how many gigs I've played in tiny bars and Cat's still haul this setup in then can barely turn it up . I get it, own one myself but for gigs my Fender Reverb Deluxe is more than enough . And I'm all about the "One Trip" motto. I want to haul ALL my gear in just one trip from the car to the venue. To each their own though , these are classics for a reason . It's great feeling to stand in front of one and feel it thump right through your chest

That was fun to watch. When I worked at Sam Ash (USA music store chain) I got to play through 3 Marshall full stacks - barely had the volume cracked open - and it was deafening, no doubt, but MAN what a FEELING! Chugging on the E string and just feeling it pound my chest was amazing. Hahaha. Absolutely completely impractical for any musical situation ever. But it was awesome to experience! Also I'm really impressed with the tone you got here. I saw Tele (bright) + Marshall (also bright) and prepared for icepick tone, but I was very pleasantly surprised. Well done!

It's interesting. I would never own one again these days. The last 100 watt Marshall I had was about 20 years. There's just no need for me to have one these days. But that really goes for a 100 watt of any amp. The volume is just way more than you really need in playing out these days and there not what I would practice with. Even with a load box, as it's just using up tubes when I don't need to. As I sit here watching videos while practicing into my Fractal FM3 into a ISP active guitar wedge. Even the Mesa Mark V 25 I have sitting next to it, I never max out.

The loudest Marshall is a 70s jmp100 with a drake transformer with kt88s. A matamp 200 watt "green" is the loudest I ever heard.

That's a nice call on the JCM-2000 DSL--one of the better Marshalls _ever_: The designer of the JCM-2000, Santiago Alvarez, is a genius. Also, replacing the fiberboard back-panel of a Marshall cabinet with a panel made of high-quality birch plywood really improves the overall frequency response of the cabinet. Years ago (1990s?), Marshall started installing the sawdust-and-Elmer's-glue back-panel as a cost-saving measure; the original Marshall cabinets included birch plywood back panels. :) If one happens to be handy with a saw and a soldering iron, replacing the back panel of a Marshall cabinet with a high-quality birch plywood back-panel is both inexpensive and easy to do. You simply pull off the old Tolex and re-use it on the new panel, with the help of rubber cement. My 6100-LM (EL34 model) roars through a 1960 Classic (with Green-backs).

I think these amps sound noticeably louder to modern guitarists simply because we are used to smaller more controllable amps, not many of us have the space nor the kind of shows that would need a stack bringing the volume, winding up a stack is brilliant fun though and I recommend it if you haven't had the chance, almost every local show I have played has the usual deluxe reverbs and ac30s but even then they have a ton of volume behind them, if I could transport a stack and use it to its full potential I absolutely would though.

Omg you said you were gonna do this on Wednesday night & you have

Just think….EVH used to have his Marshalls cranked every time in the early days in small clubs and the backyard parties. No earplugs in those days. What does it take to blow a Celestion speaker? What a score on this amp and cab James.

Nothing beats a marshall!

It would have been interesting to hear the clean channel cranked and how long it stayed clean for to compare... with the ultra gain channel it just sounded like you were piling on more clipping and compression.

That is terrifying, i'm only wearing headphones and i can just tell that thing is ungodly loud

Dude your meter says maximum of 112.2 dB that’s why it’s not going up.

I can only get mine at 1/3 volume for a few minutes in my house before my ears start hurting. That hard surface room has got to be insanely loud.

FFS, chaps, use a proper dB meter! An iPhone mic will max out at around 112dB, so it's likely to be far louder. Even a cheap uncalibrated one from Amazon will do a much better job. This is why you stopped getting any dB increase once the volume was turned up. Assuming the speakers had a typical sensitivity of 97dB for one watt (it may well be a bit more), 112dB at a metre away is a 15dB increase. 15dB increase over one watt indicates around 34 watts. If the speakers had a sensitivity of 100dB for 1W (say vintage 30s), then that's a 12dB increase and around 16W. (Having multiple speakers sharing the load makes measurement more difficult but the principle is the same). 100W of power from the amp should generate 20dB more than the 1W figure, so 117dB to 120dB at 1m depending on speaker efficiency. And as power amp watts are normally measured at the 1%THD point (when the sound is still very clean), you will get a lot more watts out of a valve amp as it gets turned up and distorts before it reaches its maximum . Solid state amps clip and reach their maximum output shortly after the 1%THD point is reached, but valve amps keep on going for a lot longer (one reason valve amps are 'louder' for a given wattage). I remember reading an International Musician and Recording World test of a Marshall 100W amp back in the 70s where they measured around 182W when flat out. 182W would give 22.6dB more than the 1W figure, so between 119.6dB and 122.6dB. Note that there are adjustments from straight theory when using multiple speakers, as the close proximity of them in a 4x12" gives an increased bass response and a modified sound dispersion pattern, so you may get 1-2dB more than from a 1x12" cab. And always use the meter at the same spot the same distance from the amp. There's an inverse square law for sound (though this is modified by being in a smallish enclosed space). Moving the mic even a short distance can change the value significantly. 1 meter from the sound source is the normal measurement distance for this sort of thing. And when measuring the external noise level, (or rather the amount of dB attenuation), you need to know what the background noise level is first (no guitar) , then measure the noise level with guitar, and then work backwards to work out the level of sound getting through (Google adding two decibel values if you are unsure). You can't just take one value from the other, especially if the two external dB noise levels are reasonably close.

Hi guys, I downloaded your Studio Rats ‘80’s patch off Tone Cloud today and it sounds great! Started playing EVH with that patch and it sounded killer. Weirdly, started playing a couple Cars songs and even THEY sounded great. It does what it says!

This is a great way to have debilitating tinnitus and hyperacusis later in life. Your hearing is permanently damaged even if your ears seem to "recover" in a day or two. Hearing loss is a leading cause of dementia. Imagine how attractive you will be to women when you have them repeat everything twice. Imagine how well rested you will be after sleepless nights with loud ringing, clanking and hissing in your ears. If you want all that, be my guest.

How accurate is that phone app?

By far the loudest concert I've ever been to was in February 1994 on the Black Sabbath "Cross Purposes" tour at the State Theater in Detroit, MI. Their line-up at the time was Tony Iommi-lead guitar, Geezer Butler-Bass, Tony Martin-Vocals, Bobby Rondinelli-Drums, Geoff Nichols-Keyboards, with opening bands Morbid Angel & Motorhead. I'm not an Amp expert so I don't know the wattage, specifications, etc.. about what they were using. But basically Iommi had on his side of the stage, four double-stacked Laney amplifiers for his Lead guitar, on Geezers side he had four double-stacked Marshall amps for his Bass. And the keyboard player (who also did backing vocals, and on a few songs played a 2nd guitar) had some kind of Peavey amp. The thing was, this theater was such a small place, it made it that much louder. I couldnt hear hardly anything for 3 days afterward, and you could feel the floor rumbling underneath you a lot of the time it was so loud. *BUT- in 2007 I went to see Black Sabbath (or "Heaven & Hell") as they called the band at this point, since Ronnie James Dio was back singing in Black Sabbath again for the 3rd time at this point). In London, Ontario Canada at the John Labatte Arena. Their Line-up at this time was: Tony Iommi-lead guitar, Geezer Butler-Bass, Ronnie James Dio-vocals, and Vinnie Appice-Drums; and opening bands were: Down & Megadeth. The problem at their concert this time, was that it was in such a huge arena this time, the sound wasn't even close to being as loud as when I saw them at the extremely small State Theater concert hall in Detroit in 1994. They used the exact same kind and number of amplifiers as they did at the Detroit concert, Four stacks of Laneys on Iommi's side, and four stacks of Marshalls on Geezers side. But being in such a huge arena this time, I think they should have added some extra amplifiers. Granted, I was on the complete opposite end of the arena from the stage this time, While at their "Cross Purposes" tour in Detroit I was only about 25 feet from the stage.

Yep. Too loud! Used to sell these years ago, too loud then too 😅 always loved the plexi though. Get an attenuator!

As it should be heard and recorded. The 1970’s proved this.

Every Marshall demo (post JCM 800) I have seen basically ruins the Marshall name for me. The tone I hear in the demo's are horrendous. This "experiment" if we can call it that, earned my Like, Comment, AND Subscription to this channel. And somehow...I want a Marshall now...

That's a beefy tone right there! Just the amp itself!

Do the same test with a Hiwatt DR103! I'd love to see how they compare in volume.

The sound of the 70s n 80s...we loved playing that loud...I used two!!

I want to see those tubes GLOW!! I had a 120w all-tube Bugera combo amp that I sold before I ever got to experiment with it like these guys are doing.

I had JCM 900 that sounded amazing, had to sell it because it only did at high volumes, which I can't do home. New Katana II can be dialed pretty close to this (I know, it will never be like real tubes) but my wife hasn't kicked me out of the house so, that'll do

Back in the late 90s I borrowed a dB-measuring device (what ever it is called by professionals ;-)), turned up my JCM900 100W half stack and reached 126 dB at max. Loud enough to kill a candle.

Bet the neighbors were “all in” during the filming of this video!

Why not get a decent calibrated device to measure the Db level?? Using a phone is really pointless.

I had a JMP 50W head going through a 2 x 12" cab when I was young and I would run it at 0.5 for a comfortable level to play with the band. After a while, I switched to setting it at 2 and turning the guitar volume knob down. These Marshalls are insanely loud.

My guess is that most of the sound outside is through your wood ceiling.

I had one of those. The green channel was excellent dimed in crunch mode with a boost in front. The Ultra channel was just okay to me. Too fizzy and had some strange EQ sound I could never EQ out to my liking. This experiment would be fun with a healthy Super Lead.

Remember those facts when you raise the dB by: 3 dB - is a doubling of power 6 dB - is a doubling of voltage or sound pressure level (SPL) 10 dB - is considered to be, to humans with a non linear sense of amplitude, a doubling of apparent loudness.

Half-way must be 5.5....because it MUST go to 11.

Excellent progress on the build, dwarfs the old place! 😲 Very early gig of mine, many, many years ago - Dick Dale - 2x 2203 JCM800 heads pegged w' a 1960A cab for each. Cabs at the back of the stage, turned to point at the wall in a 400-500 capacity room. Knock the wind out of you & then some......

Good news gents, as it seems you need to do the test again, because setting the meter for A-weighting is really only part of the story. Try C (complete) and especially at the end, you'll find far more!

I think the app only registered up to a max of 112dB so the amp could’ve been louder than reported.

You need a real SPL meter. Phone SPL apps are garbage. That amp with a 4x12 cab should do about 124 dB at one meter from the speaker baffle.

I have this amp and I love it! but I think you can get a couple more decibels out actually with the clean switch because the Distortion is clipping.

Crank it!!! Then use an attenuator to drag it down to reasonable levels...

I randomly bought this amp before I knew what amp models even were. I am grateful for my beginner's luck.

that's why i sold my diezel,and play a 20 w silver jubilee now,.....and i am a very happy man.......

Your meter had 112Max in the bottom right, was that the maximum measured, or the meters maximum? If the latter, a real DB meter would be a better choice, and so far just about every studio I have been to had one, as well as every sound guy at a venue because of volume threshold laws.

747 takeoff..120db...Motorhead show...130db....The stage volume of some of the old school guys...AC/DC, Iron Maiden would kill most people

I like how he kinda stood back and reached to turn it up, like he was afraid to get close to it.

It muds out massively at full volume. If you want to "hear" the power tubes, turn up the volume, dial back the gain. If you want saturation, turn up the gain, keep the volume where it sounds best, and add an OD if you need even more "push."

Well....I would say with two cabinet stack Marshall 100 Amp is pretty dam loud...🤣 turn down the dang tone.....it's because of the tone volume...

Awesome. That tele sounds so FRIGGIN SWEEET through the Marshall. WOW. What effects did ya use?

I’m still able to take 2 100w Marshall jubilees out to shows and can usually have em on 6/7 vol - outdoor shows - truly blessed I’m not in a band that I have to be wired direct to PA

I remember first and last concert of Yngwie Malmsteem in Poland. in well proof, small concrrt hall in Katowice (now it is Miasto Ogrodów). Hall was prepared for orchestral playing or theater... But there was a lot of YJM Marshalls Everywhere. It was monster sound. Tons of Decibels. i did not hear for 1 hour. after.

102db inside...74db outside. My calculator show 28db attenuation.

To think I used to gig regularly for DECADES with EVH5150 and cab.... no earplugs... I now struggle at times with some of the high mid frequencies in one ear when mixing 😢

But what if you could turn it up to 11? "You know, it's one louder, isnt it?"

Out of interest the 50w PLEXI 1987x Was tested and was Louder than the EVH 5150 100w..

I have a 100-watt master lead (Super lead with master volume) and it is so loud it scares me to turn it up. Before you reach half volume, it is Bizarrely Loud. therefore, I never play it. I have a dsl 40 combo and that's plenty loud for me.

Always proper fun diming a Marshall. Might want to have the checked over by a tech. A healthy 100 watter puts out more than 112 😊 my 76’ superlead running 2 el34’s through an open back cab with 97 db speaker peaks at 119 and my 100 watt 6100 peaks at 121. Looking forward to seeing how the new place turns out 👍🏼

for those that are interested it other marshall levels, i have a plexi 100w slp. a 1959 cicuit. through 2 12" speaker ( a quarter stack) on a proper db meter it reads 123 db 6 feet away. i put it through a rivera rockcrusher attenuator most of the time. let me say you need a good attenuator to pull 120 db down to 90 db and withstand the heat load.

This is a freaking beast of an amp!!!

People watching this have no idea how loud it is. With hot guitar mic and distortion pedal its loud at 3.

Me to my neighbors at 11:00 at night

Why are all these videos always about 109 watt Marshall’s? What about a 100 watt, all tube, by any other brand? Blackstar, Randall, H&K, EVH, Peavy… etc, etc!?!?!?

You think that’s loud. Try a ‘71 1959SLP Now that’s a loud circuit.

Great amp. But if you think a cranked 100 watt Marshall is painfully loud (which it is), you owe it to yourself to try the same experiment with a HIWATT DR103. Unbelievably loud amps.

Owned and gigged with a Marshall JCM 900 100 watt combo amp in the early 90s. Played in a german metal band aka KMFDM style music. Three channels: clean/crunch/death ray. Third channel live cut heads in the crowd..ha ha now older and slightly deft. But yes, those amps 'open up' when you bring out the gain and master past 1 o'clock. But in today's world, you can't play small clubs with that kind of volume. Overpower the band...

Well isn't it obvious? It's 100 watt... Before someone sparks up, it's a joke....

A Marshall 100watt Head sitting on top a Marshall Quad cabinet, cranked, has never sounded 'Weedy'. Not ever.

Not sure but I think this qualifies as half stack. A full stack would be two cabs with one head.

I have gotten close to 120 dB with 30 watt amplifiers with one speaker. A Vox AC15 can comfortably get 112 dB loud

Tube amps need to be driven to sound good and a 100w head with a 4x12 cab in a small room is ear bleedingly loud when it gets loud enough that it starts to sound good. A 100w+ head needs an attenuator unless you are in a large or outside area. Probably need one with a 50w head. My 1x12 30w can get uncomfortably loud... Also, some phones can't register high DB's well, so it may not be a good test. I'd bet you were hitting 120-125db maybe more. The actual speakers, room dynamics, etc can all effect it. Next time try and find a real DB meter which can measure to at least 125-130db. If you can peg that you're doing something! Take measurements at 2m in front of the cab if you can. Also, remember that great ear protection is in the 30db reduction range. If you're pegging a 130db meter then you're experiencing 100db of sound which you should not listen to for more than 15 minutes. 85-90 db is the limit for long term listening and really you should be below 80db if you can. 80db is a loud alarm clock BTW. 85-90 is a chainsaw.

interesting video. glad you did the outside measurement . looking forward to seeing the final result. I'm a retired audio tech and I've fixed and measured a few Marshall amps. my audio power meter tops out at 100 watts and all Marshalls were able to take it past full scale (so let's say 105 W or so) no F amps ever made it close . 85W being the best. but of course the dB difference is insignificant. i did a video measuring the boss katana in here somewhere. it talks about dB a bit. good to see you are now getting lots of views and likes.

I'm surprised that you didn't get uncontrollable feedback at those volumes because you are standing so close to the cabinet.