Secrets of the Vox AC50 - BUSTED BEATLES AMP Repair!
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- čas přidán 27. 06. 2024
- This is a 1965 Large Box Vox AC-50 (Mark 3 OS/072). It was sent to me for repair. (No sound.) These AC-50 amps were used by a host of bands, mainly from the British Invasion, including The Beatles, the Rolling Stones, The Kinks, The Animals, Herman's Hermits, etc. We'll open this one up and examine it thoroughly, change the original electrolytic caps, change the output tubes and bias. And finally, we'll demo it with a Telecaster. Sources: voxac50.org.uk/
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Thanks to Zak for his follow-up video when he got the amp back! Check it out! czcams.com/video/LhH3aDpIUwg/video.html
The Guitologist I used to love playing a freinds who had a little shop down on Madison , “mikes music “up from strings and things at the time if your farmiliar with Memphis but ,the ac50 has the most incredible brown sag even slower than the 30 , I have one a freind builtand probly closer to 35 Watts with a dual tube rec that sounds quite close and am proud to own and play and know the builder , the pawn shops won’t lend money on them ( Robt Henson built amp w no name ) and this has enabled me to keep them through the years.
Man that AC50 sounds pretty raunchy but it's cool....definitely hear the Beatles tones in it. They must have used them a lot even for recording from the sounds of this amp. I know they used AC30's too but I think they used them briefly then moved to these. Not sure.
@@HiHello-ku1fl I believe they started using these around the time of a hard days night? Same amp the kinks & yardbirds used.
The AC50 is the best-sounding VOX amp, in my opinion, followed by the single 12" early AC15. We used to have eight of them at a store I worked at - and no one wanted them. Soon, everyone realized the Beatles used them on that first American tour - you hear them in the amazing Ed Sullivan and Washington concerts. Their best guitar tone ever!
So nice to hear something other than a Fender or Marshall. Nothing else has that Vox sound. Best sounding amp for "rock" music IMO. Highs aren't harsh, bass isn't saggy, balanced mids, just perfect.
I can't believe how much gain this amp has! Marshall didn't catch up to this amount of gain until about the mid to late 1970's! It's nice and smooth gain too. I bet this is a very loud amp too. And the component placement and lead dress look sweet. I WANT ONE!!!
I got my Vox AC50 in Lexington KY in 1981 and used it for as my main amp for 35 years. Still has the original tubes. I recapped it 20 years ago and now it is time to recap it again. Thanks for the video. So much good info compared to 40 years ago.
This man really knows his stuff. Very informative background history on the various components examined. I wish I had this sort of knowledge...
A legend of an amp! The tone controls on vox work in mysterious ways.
Having played virtually EVERY model of VOX - and many of each model, I can say that I think the AC50 is the gem of the bunch. They are rare now, but used to be unwanted and always for sale cheaply. The AC50 cabinet is also the best-sounding guitar cabinet I've ever found. Incredible combination - and now so rare. The Beatles on Ed Sullivan (and Washington DC concert) is all AC50 amps for guitars.
I have a later AC50 and love it. But too HEAVY for standard club gigging. If I ever do major tours, it would be in, but it's too easy to wreck them, and the tolex is like old lady skin, what a terrible choice that was. But it's great.
Daytripper sounded very authentic, good choice for the first demo.
I don't usually do covers in the demos, but figured that one was necessary. Had to stick some "Walk Don't Run" in there too.
@@TheGuitologist As well as a Stones lick or two.
Indeed, great!
@@TheGuitologist "Walk Don't Run" was recorded using a Jazzmaster through a Fender Twin.
Same mods that I would have done to that amp. I'm on Louisville too (active musician) and have to do repairs/mods on my amps. Been in electronic field since 1976. Love bringing this stuff back to life!
At one time if you looked at the interior of ANY electronic product, you'd have seen fuses. Everything was tubed. And Great. I had a tube amp in the 70's and performed the very same test. The amp down a flight of stairs in my house. It's my opinion that Playing, not violence caused the amps to fault out, not the tubes, although the tubes blow in the process of playing.
Now that’s a cool amp! Quite a few over here, UK. On an AC50 the first two reservoir caps are both 32μF. Also for interest, those dual caps have a higher current capacity on the red and lower on the yellow. If used as the first HT reservoir, then red is always the first used in line and has its ripple current marked on the case. Great playing as always.
I’ve watched this a few times. Mine was sold to me as working, but….. it’s a Mkii which has a GZ34 rectifier and no kathode resistors. In its past it had power supply failure. Power tx replaced with the correct Haddon, the GZ socket had scraped clean carbon tracks and other poorly replaced wires and components. My house voltage is 122VAC which put about 570vdc on the 550 volt caps. I built up a couple of 700 volt caps. Good to go. The amp is sounding great. I have NOS EI EL34 and all euro 12A_7 tubes. I expect my repairs will outlast me. It scared me when I saw the condition when I first opened it up. I’m glad this is a hobby, it’s taken me over 40 hours to make it reliable.
Brad..I appreciate the work you do. You're an inspiration! From an old 65 year old enthusiast guitar player and inadequate repair guy.
I grew up in OKC. When I was about 12 or so, our next door neighbor, who was USAF(I think, could be wrong), he was always playing a Vox guitar through a Vox amp.(AC 30 maybe. Didn't keep up with amps guitars etc back then. I got a TG&Y guitar for my 7th birthday (put Mom in the hole $5). But I do remember how clean that guitar sounded. He played a lot of Johnny Cash, etc. BTW I had to play C&W if I wanted to practice in the house.(Dad's orders!). Speaking of which I've played 50 yrs & think you're an outstanding guitarist.(I don't pass around compliments btw). Love your videos.
That might be the best sounding amp I've heard on this channel!
Cool man, glad you enjoyed it!
Hell, it could be the best sounding amp I've heard on ANY channel!
I've heard lots of AC-30s and AC-15s, but hardly any AC-50s. I like the way this amp sounds very much. Ya done it good!
Just got back from shoulder surgery so no playing guitar for me. But I am feeling no pain and what better time to watch you and uncle Doug and digging on those happening tones! Aah yes,life is good! Great video.
Hoping you have a speedy recovery, Philip.
Awesome job (as we've come to expect), Brad. It was a real treat to look inside a working amp of this type: hope you had as much fun doing the actual work.
Back in the '90s, I had to spend several months working on assignment in the Czech Republic; it was not long after the Velvet Revolution. I knew no Czech, but I kept asking those who knew a bit of English about Tesla. Finally, one day, they piled me into a Skoda (wish I could have brought one home) and we drove off into the country, and I was treated to a very limited tour of what I was told was the Tesla tube factory. I wasn't allowed to take any pictures, but at the end, they let me buy all the tubes I could carry (for about $2 a pop), and I still have a pretty good stash of lead crystal EL34s at home...should last until I croak...
Awesome story! I'd love to go on that tour.
Really enjoyed the tour of one of my favorite amps and until now, I never saw the insides. Great Video. Thanks so much!
I never owned a Vox but I was always very impressed with their construction. Solid.
It was made to be serviced and used. Vox is not a museum. They sound so good.
thanks for making these videos! it is stunning to see how differently these amps been designed and assembled. this one looks like a neat one!
I need that amp now. Sounds awesome. Great playing and repairing as always.
Thanks for your enthusiasm - my (mid1960s) Vox AC50 was originally equipped with a pair of columns (each containing x4 10" JMI speakers) - a mid-60s PA head not an instrument amp head.
The only Vox guitar amp combo I had was an AC60 mounted on its speaker cabinet.
Happy to share.
Man, that is one sweet sounding amp....! Wow...! None of the Vox's I ever tried sounded as good as this one...
Hey, Brad !
I've been watching your YT channel for the last year, and everytime I turn on my PC, one of the first things that I check is to see if you posted a new video ! I just want to say that I've been watching since I've came back to messing around with tube amps, and you've helped me a lot and made interesting for me to come back to it. I've worked at a local workshop in my country for three years straight, building only Fender tweed-era replicas, and I've stopped because I was diagnosed with two herniated discs on my neck and I've switched my main working area. I'm better now, and I'm back to building amps part-time and your channel has been as interesting as ever !
Best wishes, Rafael.
Oh my! Finally the VOX amp! Love the video
Those Vox amps are great sounding I like that one.
So intriguing to see how this amp was put together versus something American or Canadian... very cool indeed. Thanks man..
You're absolutely brilliant at everything! Thanks for the video!
I always thought the Beatles use ac30, I didn't even know there was a 50 watt. This channel rocks and should be on TV.
Just watched a vid from Rhett Shull where he played in London at an event using an AC30 cranked up to 10 almost. He was pretty impressed by it, from what I saw.
The first tube amp I built from scratch in 2003 was a Vox Cambridge Reverb (US Thomas Organ era design) clone and I researched the Internet for 9 months before I built it. One of the things I discovered about Vox tube amplifiers is that their tone stacks are widely known to be interactive and players learn to exploit that characteristic deliberately. I really appreciate your CZcams channel and want to thank you for this particular video featuring a Vox design.
Thanks Thomas. Did you video your exploits? I'd like to see that.
The Guitologist Sorry, no I didn't. I did document with photos and drawings but it was my first time and I've learned a lot more since then.
The Guitologist I should mention that it all worked the first time I fired it up including the reverb and tremolo.
One of the best amps I have heard on your bench. I love that sound. That amp is a keeper
Cool, mang. Glad you enjoyed it!
Thanks for another great video,takes me back to my first decent amp an early sixties AC 30. I played a strat through a WEM copycat(tape echo) into the vox for that Shadows sound,I wish I'd kept that amp!
This is an oldie but I've got almost the same amp on the bench here and your video was very helpful. I know we don't agree on much but the images were exactly what I needed as a confidence check.
I had the same one...! Exchanged it for an 100w 'Acoustic' combo, in 1999 (the wooden model, 164 (?). Stil have it and is my favorite amp ever.
That amp and you playing the Beatles on it.It sounded just like them. Your a good player (The Guitologist)
Fascinating ... I completely understood the guitar playing bit at the end. The rest was an interesting blur of mostly the removal of 'Made in UK' components...
Matt Allen That have worked for more than half a century!
2:50
That's the magic smoke effect switch, great for every stage show ;)
By the way, Great job on Day Tripper. I’m the guy who use to play with Jerry Reed that is buying Proto.#1 from Tony Dorris of Volition Amps.
Nice historic photographs views of AC50s in action plus great views of the amp plus good repair job! Between your playing and the owner's playing in the follow up video , a good listen to the AC50. The best hint I got from the repair was the new flexible output leads , and the setting of the variable grid bias pre-set resistors was interesting.
More Vox please. Vox Groovy! Thank you! You know... I mean, keep an eye out for opportunities, if you can. I realize you get what comes in...
Wow... in my opinion, this amp was engineered very very well. I’m so happy to see inside this thing.
Thank you!
I fixed one very similar in the late 90's it broke my heart giving it back to the owner. Had same cap and worn anode resistors. Great toneful amps.
Oh yes! Walk don't run on a tele through a VOX, very cool, now with a little (a lot!) of reverb. Fantastic sounding amp and amazing guitar work! Thanks.
i like the idea of an advertisement at the beginning rather than sending products for review.. even though i know you are to be trusted with this.. still can't shake off the feeling, that if you get something for free.. you are biased, at least i would be.
I really like these videos where you fix an old amp
It's snowing in my end of Canada... enjoying the same coffee beverage and watching Brad.. great way to start the day
Glad to have my Canuck friends along. Either y'all are real badasses up there, or you just have really warm women to cozy up to.
the latter... if not, I would have been dead in a snowbank years ago Brad!
That sounds surprisingly good!
Love the way it breaks up on the hi channel. I mean, wow.
I have a "newish" Vox AC15 amp (my guess is 5 yrs old max) and I absolutely LOVE it. I pulled the back off and was delighted to find that there is NOTHING inside of it that can't be fixed/replaced with a soldering iron. All the circuit board components are throughhole mounted. I don't know if all the major tube amp manufacturers still make them this way, but I think it's bloody fantastic. At least there is one thing being made today that isnt disposable junk.
I was just thinking recently about how I don't think I've seen any Vox amps on your channel. Good to see one!
Thanks for watching, Cody.
I fell in love with vox amps i just got myself a VOX AC30VR and god it sounds really great! Till now its the best hybrid amp i've ever heard. Great video as always!
I was never big on Vox until I went over to a friends place. He was a Marshal guy, had a huge ass collection of Marshal heads, combos and cabs but he had just picked up an AC30 for a steal from somewhere and was putting it through its paces. My god that thing sounded amazing in person.
wingracer 16 same with me, the only reason i bought the vox is because i wanted a new amp and then suddenly I saw it for 185 euro's and instantly fell in love. I was gonna go with a jet city 50 watt full tube and a 2 x12 cab but that was way more expensive probably would have gotton me closer to a stoner rock sound but this vox is pretty versatile to!
Great video. You’re very good with these amps. What a fantastic amp that. Very interesting all round. Thanks!
i love those old vox amps and time period, i have a picture of Paul Revere and the raiders standing on top of there vox stacks in concert
That’s a great sounding amp! Nice work
Brad, Your videos need to have a "Mojo" alert. This has it in spades. If only those original tubes could talk! Awesome stuff. :)
I still shudder when I hear the phrase “Hammond organ that I disassembled”
nice to see a classic VOX on your channel!
Brad, I love your channel and your playing. Your demo of the Telectro reel to reel mod has tons of tone, which speaks both to your playing and your tech skills 👍👍🤟🤟
Thanks Brian.
Im up at 3am watching your vids again ! Im an addict ! Thanks for such compulsive viewing.....
Hi Brad. Fantastic video. Thank you! 💚🎸
That sounds FANTASTIC!
Loved the playing at the end. I have a Butterscotch Blonde G&L ASAT, that I put a black pearl, 3 ply guard on, just like yours. I also loved RCA the banner hanging behind you, I worked at the RCA picture tube plant in Marion IN. for 16 years, until it closed and moved to Mexico (screw NAFTA).
Thanks a lot for this video Brad, first time I’ve seen the insides of a VOX and it’s really a cool amplifier. Also seems like it’s build really well too. Your explanations also were really informative. I love it when I learn stuff during your videos. The diode board was interesting to see and it was also interesting to see your oddball capacitor values. I’m glad you set and figured out the bias where everyone could see it, that was really great. Damn, it sounded amazing too! You totally rock.
Thanks for watching, as always, Buddy. Good to see you.
@@TheGuitologist Brad! Anyway you could do a tutorial on how to switch the ohm selector on one of these babies?
As a huge Beatles fan its cool to see these old amps. I had an old solid state Vox supreme head 25 years ago, it wasnt in the best condition electronically although it looked in pretty good shape from the outside. That amp was noisy (hiss) as hell due to some problem that i couldnt find out at the time since i didnt have the knowledge then, it still sounded good for bass which i used it for in spite of that and i used it for a few years and later sold it. I think i remember seeing The Beatles using the supremes as well in pictures or videos.
Great work... Sounds amazing.
That death cap was cracked pretty bad, that's kind of scary. Nice Amp that is one powefull Vox and it sounds great. Nice video Brad.
As a Vox fan boy, loving this soooo much!
great vid! My friend is an ace amp designer (Alanis Morrissette's guitarist uses one of his amps) and does a killer mod for new Vox's that'll make them sound just the ones from the 60's. His name: Kurt Calder. BTW thanx for the Ventures....now I feel justified...you play it like I learned it...from the "Golden Greats" LP.
Two versions. The one on Golden Greats is the '64 version.
Cool bro, I'm just getting back into this stuff, after a hiatus of about 15 odd years, and though the 'surrounds' (I'm in New Zealand and tend to have to build from scratch) the outlook tends to be similar... appreciating your sharing Dude!
as always, your attack and vibrato add to the overall sense of the amp's sound ;-)
Thanks, Tony!
Love your playing man
Thanks, Terry.
You aren't kidding about this being a Beatle amp, Day tripper sounded like a guitar studio track. Great repair video, you know your stuff.
At the Washington Coliseum show, Paul was playing through an AC100.
IIRC ... Paul was the first to get a 100, as his transistor T60 was blowing ...
That's a very neat way to put the components
Great video, mate. Love the channel - keep it coming!
really like the way you did that advertisement. having it short and in the beginning means I'll actually watch it. I'm happy to click "skip" on those long winded ads at the end of other channels.
but one of my favorite things about your channel is the honesty. seen you tear into shoddy craftsmanship and trust your judgement. make sure you're not ruining your reputation by being a spokesperson for bullshit!
Thanks dude. That comment really means a lot. I am trying really hard to balance being professional and yet loose, and yet having the channel help me make ends meet all at the same time. I don't always get it right, but I've never been accused of being perfect.
I'm happy you went with that socket "fix" (spacers, other side of the chassis).
Another nice vid, Brad. Loved The Ventures bit at the end.
Great video! Sounds great to me!
Wow another great amp...the Vox! I must've been 3 when they came out
Please, when swapping out Double Cans do not replace them with tie-wrapped Nichicons... that’s russion style.
F&T makes really reliable double cans which fit and look nice in such a precious Amp!
I was thinking about that when he did that. I don't know anything about electronics but I do HVAC. We use dual capacitors, that's what we call them, & some guys will install 2 single caps if they don't have the dual cap they need. Also I was wondering if replacing those 2 8 mfd caps with 10 mfd caps would change the sound.
Maybe the customer was in a hurry?Like maybe a gig the same night as the vid? Anything more is just second guessin.
@@charlieb.8441 I think that's right on target. Each customer will have a different set of priorities/requirements. The vast majority of my work is done for people who want the amp (or guitar) to work again and be reliable, and that's the extent of it. They don't care what's inside. Only a small minority care about restoration above and beyond functional repair. Can I do that work? You bet. But it's extra time and extra $$.
another beutiful job Brad! that would be cool to own one. but there are so many as you pointed out here on our side of the pond. Bravo!
I had one . sold it 3 years back . sorry day . but its still being played in Ireland . with a Goodman's speaker cab. . nice work bud
When I was a kid maybe about 1968 or 1969, I came home from school one day and my older brother had hauled a Vox Buckingham amp and a steel tube rolling frame up to our second floor bedroom! It was huge looking because I was like 8 or 9 years old! That thing was loud! It belonged to a friend of his, I remember my folks couldn't wait for that thing to leave the house because it was so loud! I wonder what it would be worth today! PORK RINDS! A bag of Doritos was spotted in my last video! Haha, I love BB-Q Pork Rinds!
Pork rinds, buddy! You know party's on when the BBQ rinds show up!
Thanks for the video on this, id like to learn a bit more on repairing some of the older Vox amps. I occasionally mod the newer AC15's and 30's a bit, but my knowledge of repairing the vintage models is zilch. So i appreciate videos like this. :-)
Nice Tesla tubes that were in that amp
Thank You!! ..again.. for an useful and informative video. ..from Norway..
Great video Brad and the Day Tripper riff was dead on.
3:10 - When I first saw that, I couldn't help but exclaim: "Whoa!!" Holy capacitors, Batman! It looks like a well-stocked bookshelf!
Great video, again. Your playing is great!
The AC-50 is a kickass amp. Had one. oh i forgot that I had the combo head and yea it did shock me a few times and it also did sorta have that same problem on brilliant channel.
i had one of these. Got it for a song. Great overdriven sound. Ended up selling it on to a guy in the USN.
Another great vid. Cheers Brad!
From Liverpool UK.
Thanks, Andy. Cheers up north!
great job, good work, and good playing, as usual, hello from connecticut !
You had to have been there with these amps, to understand them. They were still new to us (in the US), you rarely saw a British amp here. By the time the US got Vox, it was the transistorized "Thomas Organ Vox", mass produced on the West Coast!
I've had a couple of British AC 100s, but I was a lot closer to L.A., where the tours would save money, by selling them here, rather than pay to have them shipped back home.
I've owned a Thomas Organ model Super Beatle before.
So you KNOW how clean they were! I'm 66, and have toured and recorded since the '60's! Now I too live in a small town in Colorado (pop. less than 1,000) so shops and stores are a hard thing to find!
A company called "Thomas Organ Company" out of California had an exclusive licensing agreement with Vox Ltd UK to manufacture, market and sell Vox amps in the USA. They were mostly all solid state after 1965. It wasn't just the Beatles using Vox amps back then, almost all British Invasion bands used them, including the Rolling Stones, The Animals, Dave Clark Five, Herman's Hermits, etc. And just so everyone knows, ALLOT of newly interested guitarist wanted to sound like the Beatles back then. Unfortunately, I am old enough to remember that time period very well. Most 1960s era Vox amps that turn up in the USA are these solid state Thomas Organ manufactured models.
Great editing dude. Loved the intro. Also congrats on finding companies to advertise for your show!
Thank you! I'm glad to be working with these guys. They reached out to me after seeing my video on the subject.
I played through one of these for a few years... and MY GOD was it loud for a 50 watt... and didn't want to overdrive much on its own... likely that's why Paul played bass out of them first, and also the Vox organ used one... Paul had a custom AC100 built and that one was legendary for its rumble! I couldn't seem to get past the glassy quality on the bright channel using original Celestion 30s as a pair... it was almost hifi, with almost no rolloff up to at least 8k... and the normal channel was too bland... so I got my 1968 ac30 top boost with the rare Silverback celestion 15w ceramic speakers. And honestly, that was about the perfect amp! the 15 watt bulldogs were great, but very mild on the bottom end. there ceramic 15's offered that 60hz RES FREQ with a lot of huff... so that grill cloth was always blurry in photos... because it was loose nearly always on original ac30's... and flapping like crazy! if you ever see a JMI AC30 with the silver frame 15 ceramics, or any good efficient 15w like that, it makes a huge difference. the chunk of early Marshall's in full effect.
Watch it if those caps blow, it looks like they had a pillow fight inside! The rarity you're seeing , may have been the result of one of the Vox/JMI technicians that they used to have travel with some of the bigger(more famous) bands, to assure their product functioned the best for their company. I agree that the bigger cab is an odd one, my AC100s both had smaller ones.
Also, remember that the norm of the day, was a clean sound, no overdrive! The clean sound of an AC50, would blow you out of the room!
I've read that those smaller cabs led to serious overheating issues in the AC-100s. Never owned one, though, so can't confirm or deny.
You Rock. Thanks for posting and Greetings from England.