Recapping Vintage Guitar Amps - When is "Killing the Mojo" OK? (1959 Epiphone Century EA-25T)

In this video we will take an extraordinarily clean, rare, and mostly original 1959 Epiphone EA25T Century guitar amplifier and SHOTGUN all of its magical yellow Astron and Sprague Bumblebee capacitors with Sozo Next Gen and Orange Drop Polyester. We will discuss the pros and cons of doing this and other controversial moves such as modifying the layout and adding shielding. Technically it's a better amp, but does it "kill the mojo"? Let me know in the comments.
ABOUT THE AMP: The EA-25T Century is the Epiphone counterpart of the Gibson GA-20T Ranger, made from 1959-1961. It featured two channels - one based on a 12AY7 triode input stage, and the other based on a 5879 pentode - into a 12AX7 phase inverter and cathode biased 6V6 push-pull output. This line of Epiphones was the first produced by Gibson after taking over the beleaguered and embattled Epiphone brand in 1957. Most, if not all, Epiphone amp designs from that point on had an identical Gibson coutnerpart. The EA25 Century from this era is rarely seen, but the slightly more plentiful (but still rare) Gibson GA20T Ranger is a sought-after tweed era tone machine capable of some serious hard rock tones, dynamic clean tones, and one of the best, most hypnotic tremolo circuits ever, utilizing a 6SQ7 octal tube oscillator.
CAPACITORS USED:
Sozo Next Gen .022 amzn.to/2iVbeZp
Sozo Next Gen .01 amzn.to/2vZ9Ztm
Orange Drop Polyester .005 amzn.to/2x4wFNQ
Orange Drop Polyester .05 amzn.to/2ey5nV2
Orange Drop Polypropylene amzn.to/2wyhkno

[@TheGuitologist]

Someone asked what kind of shielding tape I used. The stuff I used was HFT branded from Habor Frieght, but this stuff or the 3M stuff should all do just as well. 3M will be most expensive. If you don't have shielding on the back door of your amps, they NEED it! amzn.to/2wBKPmM

[@TheGuitologist]

BONUS! This stuff also makes great liner for your favorite hats. ;)

[@5argetech56]

I use regular Heavy duty foil........... I use a glue stick to stick it on the wood... works fantastic!

[@TheGuitologist]

Just make sure if you glue in foil that you use a very good adhesive that wont deteriorate under heat. You don't want it coming loose and shorting anything.

[@haasjeover123]

Also staple it ;) staples trouh the overlaps also ensure better contact.

[@DeepPastry]

I decided to just go with the Amazon brand, Tapes Master, with conductive adhesive. It's cheap and way less questionable then other Chinesium offerings.

[@marcusheawood8560]

I simply cannot believe the idiocy I'm reading here, this amp was built down to a price and made to be played, what Brad has done is put it back to factory fresh using modern more durable components. Leaky caps don't add tone, they make noise. You try and go buy a 1959 Corvette still on its original tyres or original brake linings, some components are consumables and have to be replaced periodically because they age badly. Remember that when you hear classic recordings from the 50's and 60's, the equipment being used was brand new and factory fresh, it wasn't vintage gear back then. The pickups were fresh and their magnets strong, the tubes new, the caps and resistors in spec. and the speakers crisp and clean. For every 'Holy Grail' '59 Les Paul that was made there are a thousand tons of junk guitars that didn't make it through time to us, the reason that LP got here is that it was as well made as a skilled luthier could manage, using the best woods he could select, and even then there were plenty that didn't make it. Time weeds out the weak. These guitars and amps were made well enough to have survived, that's why they're deservedly famous and also why modern mass-produced gear will not survive, especially digital stuff. This vintage tone obsession is retarded, stuff that is in tip-top condition sounds better than old, clapped out crap. I betcha if Brad made a clone of this amp from all the best quality brand new components using that exact same Epiphone circuit diagram it would sound even better than this nice old one does.

[@satchmodog2]

It's the same argument these dipshits make with vintage pickups. Vintage pickups sound like thin assed shit and anyone who has really heard them and wants that sound for anything other than 50s twang music and country is a fool. I swear to all that's holy and unholy, guitarists are the biggest pack of lemmings.

[@yqwgjsg]

You are totally correct. If you were going to put something in a museum so people could look at it and observe how things were built way back then, then yes, it should stay original. However if you are going to play the damned thing, like you said, it’s like not replacing tires and shocks on a 1950’s car. Still pretty but drives like shit. So many damned experts on KZbin who don’t have a channel but know how everything should be done. I was watching a medical procedure yesterday and was floored by the number of people who knew the doctor was doing it wrong.

[@PrinceWesterburg]

I heard a good recording of Fleetwood Mac from their early days when they where a blues band, playing brand new amps and it sounded like you where playing a modern valve amp. Speakers can age nicely, vibration makes wood resonate better so guitars and cabinets can actually get better or at least more 'characterful' however I totally agree on components. If you where'nt right we'd all scour fleabay for 70 year old death caps for our amps! XD

[@isaacg6967]

@@satchmodog2 unless it's N.O.S. maybe

[@timmooney7528]

The comparison to a classic car is spot on. A show car is cool because it's parts are factory installed, however you wouldn't want to take that car around the track or use it as a daily driver with 60 year old dry rotted tires. If a person is asking to get an amp fixed, I assume it's worth more to them operational than it being factory stock.

[@KleyDeJong]

Cool update. I'm on board for updating the caps. It is an amp that should be played, not a museum piece that should be collected.

[@TheGuitologist]

I agree, this one wants to rock out. But I can also see the collectability of it. It's a 1959 Gibson, after all. :D

[@donrutter6550]

I have seen guys take vintage capacitors apart and put newer ones inside of them to look original, so take that into consideration. The part that faces the board is open so you don't see the opening.

[@TheGuitologist]

I think re-stuffing caps is crazy. I don't get it.

[@lroy730]

What about the $115 a pair of Fake Gibson Bumble Bee's sold by Gibson..>Skip to about 1:min.look >kzbin.info/www/bejne/jpa5nJKFgdZ_hck

[@TheGuitologist]

I can understand stuffing electrolytics. That's a different story. In that case, there is a real reason to do it. Single electrolytics are cheaper, for one. Sometimes you cannot find the exact combination of values in modern cans, and stuffing the old cap can means saving space inside the chassis. All valid technical and economic reasons. Not so with re-stuffing vintage caps for appearance sake alone.

[@simonkormendy849]

It's definitely a good idea to replace old caps in a guitar amp with brand-new ones as long as they are adequately rated for the job, there's really no point in having an amp 100% original and with all it's original components in place if some of the original components are faulty, or are in the process of going faulty if they have a negative impact on the functioning of the amp, I'd rather have an amp 80% original and functional than an amp that's 100% original and non-functional, amps are meant to be used, so they need to be fully functional like they were the day they left the factory, so if it means replacing some original components with brand-new ones just to get it functioning properly, so be it.

[@TempoDrift1480]

Simon Kormendy same

[@telecasteroil]

That amp sounds so awesome Great video again .

[@TheGuitologist]

Thanks for watching.

[@LanceisLawson]

Unlike guitars guitar amps don't get better with age. Eventually things get weak out of spec or fail outright and you're left with an unusable amp. So much for Mojo. Mojo is for uptight babyboomer males sitting in their dens. Replacing tubes and caps unless you're a total klutz brings the amp back to what it originally sounded like. Old untouched equipment is great but it's useless for working touring musicians who need reliability. A lot of the guitar heroes onstage with vintage equipment are in effect playing fully reconditioned units that just happen to look old. IMO you do what you have to do to keep it working and reliable. Good call you made.

[@benasanceris4299]

Lance Lawson You're wrong.

[@Ferretsnarf]

How is he wrong? It's a simple fact. An untouched amplifier does NOT sound the same as it did when it was new, or hell, even when it was half the age it is now.

[@donrutter6550]

Correct. I have David Allen Coes old Twin cabinet with a new board and tube sockets, it gives the appearance of vintage but with the same mojo, thanks to nos 50's and 60's tubes. I use Svetlana winged C tubes which are closest to the RCA blackplates on the 6L6 which were always the best. Regular Svetlana 6l6's are just sovteks so get the winged c. Preamp tubes that are nos are still affordable and better than the Chinese tubes available today.

[@benasanceris4299]

Ferretsnarf Amps sound better with age, because of component degradation and other stuff. It makes the sound more natural and dynamic. Original 59 bassman is probably the best sounding amp. Reissues don't even come close, but then again you have to learn to get a good sound from an amp first and only then say how old amps are worse.

[@brushcountrybob5347]

How is Lance wrong?What good is an amp with original leaking failing caps?Which will no doubt further the problems and cost a heap more money to repair in the future.Sounds like the owner wants a playable amp to enjoy for another 50 years,and not a vintage doorstop that's "cool" to look at.

[@djefferson5669]

Every time Brad says "trem-molo" you must take a shot!

[@MikeGervasi]

Nice job. I like how you kept thinking it through and realized how much replacement was reasonable for the future and keeping a balance. I think it sounded killer at the end. Really look forward to your vids.

[@davemassie3726]

Beautiful Brad, Congrats on new home. Amp sounds killer! Great repair & upgrade. Thanks

[@TheGuitologist]

Thanks as always, Dave. Yeah, can't really wait to get into the new digs. I'll do a tour video when we close on it.

[@Chuffin_ell]

Just seeing those old caps gives me goosebumps. I swear I can smell that vintage smell old boards give off...

[@Wildman9]

Once again I'm watching you old stuff that apply today . Great fun.🎸🎸🎸🎸

[@cattleprods911]

Killer amp and playing, I learn so much from watching your videos, thanks! Also, the pentode channel has a Matchless vibe.

[@Ferretsnarf]

I don't understand people who insist on untouched vintage amps, at least when they mean to actually play them. An untouched amplifier is almost not even the same amplifier. You can easily bring it back into spec, with components that are likely to stay in spec for longer, and make it a safer piece of equipment while you're at it.

[@MrJohnnyDistortion]

Safer? It should be more dangerous.

[@LPCustom3]

I have a 1960 Gibson GA20 "Crest", No tremolo, Tweed covering. Great sounding amp. I replaced the electrolytics 7 years ago. and installed a 3-prong AC cable. It's in 9 out of 10 shape.3-12AX7's, 2-6V65's & a 5Y3. all the caps and resistors are on one side of the board Be nice to give it a new home if anyone's looking to buy one! I just don't play it enough as I have around 15 amps

[@michaelcrawley5211]

I don't see how you do what you do. I have watched a ton of your videos and you truly have a talent and it really is fun to watch. I was able to mod my Epiphone Valve Jr not to the extent you did it but is sounds amazing now. Keep posting these videos they are so helpful and is there any word on the string change challenge?

[@CountSpatula666]

This is a great amp to repair. Love watching this show to see some different amps out there. And love seeing the work that goes into troubleshooting the issues. Great job and great Electric Six t-shirt!

[@PhilDavisFilms]

The series of resistors and caps after that pentode is called a shift network, it's working to get the phase tweaked a bit for the tremolo to work more effectively. I learned about this working on my Vox AC30/4 that I built a while back.

[@TheGuitologist]

Thanks for the comment.

[@jegr3398]

Whoa, that's interesting

[@JimijaymesProductions]

Having vintage amps serviced is a must! I grew up playing my dads early 70s VOX AC30, one of the greatest amps, Ive played through. I didnt think there was anything wrong with it except the normal channel was a bit too dark for my tastes. He got it serviced (had changed the tubes himself plenty of times but never a full service) by a tech that knew a lot about VOXs. The amp was great before, it was amazing afterwards, just better in everyway especially the normal channel which sounded like a completely different circuit from before.

[@TheGuitologist]

A lot of times guitar players get so used to setting their controls a certain way to get "their sound", then once the amp is serviced properly, those positions move and you have to find them again.

[@JimijaymesProductions]

Yeah guitarists can be super lazy, I tell you what though in the guitar world everything changes. If you move your amp you'll have to change the control based on room acoustics!

[@brushcountrybob5347]

This amp is a tone monster! Thanks for all you do Brad and sharing these kick ass tubers with us.

[@TheGuitologist]

Thanks to all the people who keep bringing them to me and to those who watch and make it worth my while to do it.

[@merqury5]

Im regarding these vids almost as tutorials and I'm warming up to get into my peaveys that are loosing volume. Watching these vids bring back the urge to repair again.

[@whynotme5926]

I think that is one of the best sounding amps I have ever heard.

[@anthonydallarosa8314]

As someone who's been getting into amp and pedal repairs and mods I have to say your channel is amazing. I really appreciate your methodology and love the shit post fridays.

[@robinaldred3255]

Sounds to me like mojo has been added. Big time!

[@DetroitWrecker666]

This could ONLY be a major improvement! Great videos! New sub

[@TheGuitologist]

Thanks for the sub. Welcome to my nightmare! :D

[@MrUltraworld]

I don't think what you did was controversial at all. With 2 bad caps, you know the others are right behind them. You've taken the amp apart once and now the customer won't have to worry about it anymore. And you put the caps in the right place. I have a pair of '70 Plexi's I bought in '82. A few caps went bad & I had both of them recapped. They sounded as good as ever now. Great work! But what a beautiful amp, in excellent condition too. The Tremolo is lush. I Love the way ch2 breaks up so gracefully, very touch responsive. The character of the guitar shines right through. I buy amps like this one all the time, lots of low watt age fun.

[@DavidMFChapman]

I have no intent ever to work on equipment like this, but I find your videos informative and interesting.

[@phoenixlandingstudio6594]

Great video as usual! To my ears this amp sounds like it's meant for studio recording? It could be the way you have mic'd it or it could be You Tube's compressed sound, but the amp sound super crisp and excellent quality on the signal. Great work!

[@wingracer1614]

Crisp is right. I liked the channel one cleans but was hating channel two until he broke out the Ibanez with the humbuckers. That warmed her up nicely.

[@TheGuitologist]

That Channel 2 really likes humbuckers. Normally in my videos, I have the close up SM57 mic and an overhead room mic on. In this video, I forgot to turn on the room mic, so you are getting everything straight off the SM57.

[@SteverRob]

Nice work. When it comes to those old bumblebees, I usually replace them. They're getting over 50-60 years old now. I've worked on quite a few old tube ham radios, too. They're full of 'em.

[@TheGuitologist]

I don't mind them too much in low voltage areas like tone circuits, but they definitely don't need to see ANY measurable DC.

[@SteverRob]

I don't know why I do this, but I can't get myself to simply throw them away, though. So, if you ever need any... lol

[@millstap]

This is the point that scared me to death when I bought my vintage 1959 Fender Tweed Bandmaster. I wasn't sure I could trust anyone so I had to learn how to repair the amp myself. Now, if I had the Guitologist in my area, I would have taken the amp to him but only under the condition that we only replace absolutely what is necessary. I have no trustworthy amp techs in my area that I know of. I have since bought 1959 and 1960 Tweed Bassmans that I feature on my channel. They were both original and I performed their first electrolytic cap jobs. Almost everything else is original including all of the Astrons. Although, I did learn the hard way what a bad cap can do. I took both Bassman amps to a gig and before we even started playing I notice there was no sound coming from the 1959 and the drummer asked "what is that smell." I broke out into a cold sweat because I had just bought the amp. A friend of mine at Area 51 Audio Design helped me troubleshoot it. It turned out to be a shorted .1uF/400v cap in the phase inverter section and the 5881 grid had 235 VCD on it for a while thus the smell. That amp has been super strong ever since I replaced both the .1 uF's with matching NOS Astron PIO caps I bought from the Netherlands. Short story long, I have experimented with almost every boutique cap out there including the Sozos and every time I cringe because they do not sound as good as the old Astrons. I really need to find a good replacement and all I can think of now is to find some good NOS Astron PIO caps. They are getting rare too. I tried a few in the coveted .02 uF positions and they still didn't sound as good. I guess, from a players point of view, no one in the audience will ever know the difference but when you are trying to preserve the old tones that we heard on the old recordings, it becomes more important. Maybe in the recording studio is where the biggest difference will be noticed. I just don't like the idea of shotgun cap jobs but when you are in the business of repairing amps in a timely manner, it is probably the most practical approach. I've spent years coaxing the tone out of my Tweed and Blackface amps and an amp tech with time constraints just doesn't have that luxury. That is why I think it is good to learn as much as you can about amp repair. Wow. Long comment but this has always been a touchy subject for me. The 1959 Bandmaster is still completely original minus the old electrolytics and it still sounds great. Thanks for reading this.

[@TheLuckymod13]

I really enjoy watching your process. I am a self taught circuit nerd and was kind of excited to see you poking a live circuit with a chopstick. I do the same thing, not realizing it was a "thing" that is done by others. I always wanted a job like this, diagnosing and repairing old tech. Cool video, keep 'em coming mate.

[@TheLuckymod13]

P.S. Holy COW. You can really shred!

[@TheGuitologist]

The chopstick is my oscilloscope. Keeps me from having to dig out my actual oscilloscope.

[@monkeyxx]

When you cranked it up with the humbuckers it was so good. Also learning a lot from your repairs.

[@HC_GUITAR]

Brad your videos are so interesting every time, I love the content you are providing and the expert knowledge you are sharing. Keep em coming. cheers.

[@TheGuitologist]

Thanks, Hugh. Will do.

[@mickgentry8128]

Nice Amp and nice playing, dig your rebuild vids, Cheers From Australia!

[@TheGuitologist]

Thanks for wtaching, Mick.

[@bradleyard4195]

I keep imagining that second channel with a Les Paul or an SG going into it. Very reminiscent of early AC/DC to me. I dig it.

[@MegaTubescreamer]

good work brad, & a fine sounding result, some wicked noodling to showcase it all,, thankyou for posting 😎

[@JohnDoe-pq8yw]

I think I need shielding on my silvertone 1483, for flippin' sure. That thing is wide open. Another excellent video Brad, thanks again for teaching us noobs.

[@TheGuitologist]

Thanks for watching. Yeah, get that thing shielded.

[@FirstNameLastName-mo9li]

The mojo was already long gone. Any original caps that might have still been good surely would have failed in the very near future, resulting in a return visit by the possibly angry customer. Replacing all of the caps was the right thing to do in this case. The mojo is back - that amp now sounds great again!

[@ronsbeerreviewstools4361]

This is a very good video. That Epiphone amp. sounds good. 1959 amps used a lot more cloth and Jensen speakers .Now youve got me thinking of doing a video of my 3 different amps. Suggestion, I noticed two guitars with four pickups, on the wall behind you, you should do a video on them. chers !

[@TheGuitologist]

Thanks for the suggestion. If you do your vid, link me and I'll check it out.

[@ronsbeerreviewstools4361]

Yes I will, thanks. cheers !

[@ProphetForProfit]

This amp is fantastic sounding at the end. Good work.

[@TheGuitologist]

Thanks, man. I agree. Would have been even better had I not forgotten to at least turn on the overhead mic a little to pick up ambient room noise. I prefer that to straight close micing, but eh. It sounded ok still.

[@movinginstereo40]

Gorilla aluminum shielding tape........... Of Course !!!! Man Brad, I was thinking of that opening lick of Fly Me Courageous when you was playing that second channel wide open. It would have been most appropriate through that second channel. It's like hearing your kid say Gas - Gas - Gas !!!!!!!!! Great vid on the Century.

[@markkinney5030]

For a old amp now that you repaired it that thing rocks!

[@Thomasdgolden]

That bullhorn logo I love it. They are donning this logo on some guitars now.

[@theearstohear]

Good fix. Being emotionally attached to old caps because they are "original" might be find for a museum piece, but for a player it's as silly as trying to play a 57 strat with original strings on it. A definite improvement that will allow that little Epi to make music for many years to come.

[@Dan79istheman]

Brad great video again mate! Considering the nuances of using a pentodes in the input stage, if you ever built your amp from scratch, would you use one, or stick with trusty triodes? In your opinion, do they offer a contrast in sound that is that distinguishable to the triode? I have not had much experience with pentodes in the input area. I do have a bunch of EF86's in my stash and have considered them. Just curious for your thoughts. Cheers Bud!

[@TheGuitologist]

Pentodes on the input are worth it. I've built stuff with them before and I've modified triode stuff to pentode before, as I did in another recent video: kzbin.info/www/bejne/moSnqHpqg7Ggb5o If you want the best of both worlds, consider something like a 6GH8A, with a pentode and triode in one envelope. Then you can use a switch or blend knob to switch between them on the input. I have designed an amp that did just that as well: kzbin.info/www/bejne/fWXCn5x_fdh3pLs

[@emmanuelmeyermeyer1083]

Very well done. Very informative to helps us all out fix our vintage gear.

[@jeremypoythress1218]

Mojo revival with a boost. My philosophy on the mojo is Keep what you can and change what's necessary to keep it working. The onboard tremolo effect on my harmony guitar started leaking electrolyte and had a busted battery stuck in it. started working after I cleaned it restored the battery compartment and rewired it without changing much.

[@rebelcat420]

Another great video! Always enjoy them!

[@TheGuitologist]

Thanks for watching, man. Appreciate the comment.

[@bartnettle]

Nice playing! Wow! Good fix! Trem sounds nice! IS that high gain really come the amp?

[@TheGuitologist]

Yes. No pedals. Just straight in and cranked. It would break up even more if I had pulled the V1 tube also.

[@JohnIainMcFarlanewaspfactor]

Fabulous job and No,I don't think you killed the mojo.I have no problem making a great old amp more reliable and easier to work on in the future if it needs it.Bad design in part,improved by relocating key components seems to me to be doing future techs a favour,and the tone is still ALL there.Lovely job Brad.Thank you for sharing.

[@marccarter1350]

I have only ever seen them in photos. We don't see these in the UK, at all, if ever. It's far bigger than I first thought. Love the colours, I think it sounds great. I would love one of those in my life. My Vox AC15 would have issues thou if i arrived home with her :-) Nice work as always. Did Epiphone make amps before Gibson bought them out?

[@scott729]

Another really good video Brad. Cool amp too! I was wondering... probably been discussed before, but where do you like to get your electronic components (caps, resisters etc)?

[@waynegram8907]

Most amplifiers back covers don't use shielding or aluminum shielding tape. I wonder why these input jacks were picking up more noises compared to a fender amp or marshal amp that you had to add aluminum shielding tape on the back cover. The First capacitor of the Sequence is an Astron Capacitor and then Sprague Bumblebee Capacitors for the "tone shaping network". I think they used the Astron Capacitor for frequency response differences, like you mention that ceramic capacitors add an edgier tone. When pulling removing out V1 tube from a fender amp or this epiphone amplifier it increases the gain but also the "loading impedances changes" because V1 pulls down the plate voltage loading it down as well as the loading of the tubes resistance of the plate resistance of the V1 tube.

[@valsteppe7754]

I worked on a National Professional once that had triode strapped 5879's in both preamps. That amp had a sweet overdrive sound when it was cranked

[@TheGuitologist]

50s Gibsons and 50s Nationals are my favorite rock and roll and blues amps. I think it's impossible to truly understand what good tone is without having played a few of each.

[@gregwolking]

27:05 I'm curious, did you ever replace that obviously microphonic tube -- the one you put the silver shield over? That thing was ringing like a bell any time you touched it, and that can't be good. For that matter, did you replace *any* of the tubes? If so, which ones, and why? The amp sounded great once you got it all buttoned up, so I was wondering if you did anything about the tubes or I just missed you mentioning it in the video 'cause I'm old and my mind wanders sometimes. ;)

[@JoseSanchez-br5kk]

the problem is: capacitor shift usualy to lower valueswhen they age so, on the signal path that means less bass... and less bass is good when overdriving the amp (less blocking distortion). So replacing caps to original values may be a very bad choice ! When remouving old caps, always mesure it and write this information down on paper so you can restore same values but with new caps. Filtering caps on power supply: may also change the sound A LOT, but reduce the noise also. It's an art !

[@enorbet2]

Any manner of "mojo" that comes from old components, especially from leakage, can be measured, documented and recreated by adjusting values to get to the same accidental place on purpose if the client so desires. So, no, you most certainly didn't kill the mojo. Amp sounds great and you did due diligence by discussing options pros and cons with the owner. He should be extremely pleased. I certainly am.

[@TheMachinefish]

Moldy Tamales! I want that amp... Ive seen that Epiphone badge on older Casino guitars. Nice guitar work too.

[@TheGuitologist]

Thanks for watching. Yeah, this is the amp to have.

[@stevehogan8829]

Very cool looking old amp. Love the suitcase handle...Tremolo is very nice feature... Man that is a beauty. The demo of the Gibson counterpart was fantastic. Is it possible that the only issue is the tremolo? Sounds very nice... funnny how stuff tells you how it wants to be played. Thanks.

[@Choralone422]

I'd say you restored the mojo to that amp!

[@cpfs936]

Can't believe how warm & "non-icepick" that bridge Tele pup sounds.

[@JasonWaltonDriveAlong]

Taking out the old and putting in new is a bit of a sacrifice and necessary. Ever thought about putting the old components in a baggy attaching it the inside to show what was in it originally. Just a thought.

[@TheGuitologist]

That's commonly what I do.

[@JasonWaltonDriveAlong]

The Guitologist I am glad, keeping the original with the original, even if they're not used anymore.

[@Starcrunch72]

and it keeps your shop space clean of worn out parts...

[@zadvitskyguitarpedalsandam4466]

Great tips on noise source detection. Thanks a lot for your videos. Wow this is very cool sounding amp.

[@rickventura8945]

Hi Brad, I would like to know which value cap did you use to replace the red Astron .25 400v? I think I see an Orange Drop 716P but I can't tell the rest. Any other cap I should consider? Thanks!

[@blkjckgtr3075]

Nice repair Brad and great playing,nice amp!Cheers

[@TheGuitologist]

Thanks for watching.

[@JJ-JOHNSON]

Sweet amp, sounds great, that's some fine picking there Brad, oh by the way I enjoyed the video as usual, keep them coming. JJ

[@TheGuitologist]

Thanks, JJ.

[@davidstaepelaere7230]

Great sounding amp, and nice playing too! A few questions about the caps... Why did you back off on your original plan to change out all the caps? It seems like your original justification about reliability and not having to get under the board again is still solid, even if the Astrons were protecting the bumblebees from the high voltage. Why not swap out the remaining bumblebees hiding under there and just be done with it? Also what's up with the orange drops and the Sozos? Is that for appearance or tone? Or customer preference I guess. I just don't buy into the magic capacitor tone voodoo. I think the red Panasonic polys you mentioned work great and are reliable. Just curious. Anyway, I really enjoy your videos -- keep up the great work.

[@TheGuitologist]

The total cost of these caps is negligible for the ptential return if he ever came to sell it. A buyer would be more likely to think the Sozo and ODs were worth paying top dollar. The reason to leave the 4 BBs was because in low voltage situation like in the tone network after the OD coupler, they should operate ok. I'd already tested the amp before service and the tone wasn't really a problem. I also tested the tremolo afterward and it was fine with those in there as well. This thing should operate with no problems well into the future.

[@WillyMcCoy50]

Fantastic Brad and cool amplifier. The badge is a little suspect. By this time Epiphone was using the "e" logo as seen on the Casino pickguard. I have seen that badge plate on 1940s - 1950s headstocks though. Good luck with the new house and I hope it has good current!

[@TheGuitologist]

It's the original badge. This is REAAAAAAAALY early in the Gibson/Epi amp run. They may have still been using up old parts they got in the Epi deal, or experimenting with cosmetics still.

[@ChurchOfTheHolyMho]

What interesting timing for this. I just recently was wondering if capacitor / component branding made a difference in tone. In the process I read this week that EHX had a limited run on a pedal because of old stock sourcing issues... ...and that Arp hand selected certain transistors in the 2600. No idea if these are true, but very interesting indeed. Thanks for sharing your thoughts on the matter. Always great to watch you work. In the event that I ever start building musical circuits - it'll be your fault... :)

[@TheGuitologist]

I refuse to accept any of the blame! That's my one caveat.

[@bucyruserie1211]

What a cool amplifier! Sounds awesome...the diversity of tones. Looks great too. Brad I was wondering if you took off one lead of any of the bumble bee caps, and checked them whilst you had the board free? I get you figured the astron took the dc hit 1st, but its age right, that takes its toll on those caps? Just curious.. Great repair job, I liked you allocated caps to top.

[@Zelleram55]

Bucyrus Erie12 I was surprised he didn't move bumblebees to the top too just in case there were problems.

[@azzuro195]

I watched this vid as an action movie with happyending :) Thanks Brad.

[@TheGuitologist]

My next blockbuster the body count will be higher.

[@mooseteets]

love your vids, and as for killing the mojo, fk that, you just brought this amp back to life. i reckon if you copied this circuit with brand new parts it would sound just as good as one from the factory back in '59. The quality of the parts is more important than any mojo the old ones have, sure they look nice, but if they are way outta spec then its not gonna chooch right.

[@kenb.1829]

I LIKE Sprague Orange Drops. Reliable, predictable, and cost effective. Fender liked polyester caps, too, in the early 90'S. I used them back then in my audio amps and guitar amps.

[@TheGuitologist]

They hold up well. I usually use the smaller red Panasonic type polys standard, because they are even cheaper and work in even more situations where smaller components make a better fit.

[@audiotechlabs4650]

So in the final analyses, do you find the pentode channel would sound louder and distort easier than channel 1? Channel 1 seemed very clean(like a Fender) and channel 2 sounded more British.. Thankz

[@TheGuitologist]

Yes. Channel One would breakup as well with a 12AX7, but Channel Two has more gain still. Get the most gain out of this amp by pulling the V1 tube out of the amp and running into Channel Two. Crank up with some humbuckers and you're bordering on classic heavy metal.

[@LM5629]

The Guitologist What about jumping both channels together ?

[@zrkn1]

Sounds great ,would like to hear it plugged into a 4x12, i bet it would crank. Good work man.

[@TheGuitologist]

I think paired with that nice, worn in Jensen, it's just buttery good.

[@Mojoman57]

Awesome video as always. Thanks for pointing out the logo. It caused me to look up the roots of "epi" and "phone" and guess that this loosely translates to "superior sound". All these years...

[@TheGuitologist]

Epiphone is named after Epi Stathopoulo, who was the company's founder. He was originally from Greece.

[@Mojoman57]

Oh, I guess those are "facts" you got from the internet, right?

[@teleking36]

Man, what a clean example! These amps are really tough to find. Do you know how the owner came to own this? I just recently snagged one that needed a lot of TLC, but it sounds killer once properly serviced. I also own one of the two tone GA-20T Rangers, and they're identical except for the cabinet design.

[@curtisfranklin6830]

Great Job man. Sounds just simply awesome!!

[@spacemanspiff9780]

that amp is sounding killer.

[@yrussq]

wow that input shielding thing at 26:15 is crazy! learned something

[@scottbrowder4967]

enjoyed the video... almost as much as listening to you jam for the demo. Seriously, nice playing..

[@TheGuitologist]

It's weird. The whole time I was doing the demo I was thinking, man I'm totally sucking here. None of this is going to be usable.

[@fireantsarestrange]

Oh give that dude his amp back... lol. You love that thing way to much.

[@TheGuitologist]

Caught me. :D

[@closetbluegrasser]

Did I miss it? Did you identify the faulty component that caused the tremolo malfunction? Sorry, but its the why part that helps me learn. Also did you test those Astrons to see where they were at spec wise? I am curious. Thanks for the awesome videos!

[@TheGuitologist]

It was a capacitor issue. Replacement of the 3x .05 caps in the trem fixed it.

[@alverduratonejunkiealveram1017]

Hello Guitologist!!!! What are the differences in sound and purpose between the sozos and orange drops?? Thanks man, love your videos

[@TheGuitologist]

The general idea was to stick with what most people accept as good replacements for those caps. Personally, if this was my amp, I would have probably just stuck my red Panasonic knock-offs in there in every position and been done with it. But I like to steer customers toward better resale later down the road. That way they can get top dollar. The Sozos were put mostly in positions where signal passed through them in coupled stages. The orange drops were cheaper, so those were used in non-tone-critical places like the tremolo oscillator, which really only needs to provide oscillation.

[@alverduratonejunkiealveram1017]

Ok I get it. For example if you need to replace a cathode cap would you use sozos or orange drops for that position? Thanks for answers, I appreciate it

[@orange70383]

Those orange drops don't look to have the foil end identified, you have to connect the foil side to the negative or else it's going to be un-shielded and all kinds of noise will get into the circuit from external sources. You can identify and mark the foil lead each cap very quickly and easily with any cheap oscilloscope.

[@rustyaxelrod]

Man, that’s a cool old amp! So many useful tones, sounds very versatile on my iPad playing through a small pair of amplified JBL’s. If I wanted something similar to this what am I looking for? Does it have to be an Epi or did Gibson use the same circuits and components on their Gibson badged amps? What would be the key words or model name(s) to look for?

[@AMStationEngineer]

A very nice end result; those Bumblebees have bitten me in the tail more than once (in radio and TV circles), I've just shotgunned those for the last decade. One thing which I am having difficulty in comprehending, why are so many of the carbon comps complete with "jig - bent strain relief" on one end, and not the other?? I instructed Mil Std 2000 Cat "C" electronics practices for 15 years in an avionics plant, and am viewing the practice from that perspective. Many thanks, Tim.

[@TheGuitologist]

I would guess only one bend would be necessary to compensate for expansion and contraction. It's a bit extreme unless you're taking the amp to the South Pole or Space though.

[@justinbouchard]

My opinion about changing old stuff for nostalgic or whatever else the reason, is that if you had a 19 whatever canvas covered airplane with holes in the canvas would you just fly it like that? Always watching you at some point while repairing if not for information for entertainment. Love from north of Lake Superior.

[@Music10161]

It's so quiet now. The owner better be stoked, that amp sounds amazing.

[@TheGuitologist]

I think this owner will be happy. He's waited a while for it, but I think the outcome is very nice.

[@scottconnors8419]

How much did you score it for? Very Nice piece of furniture...I got a rare early usa merson built u302 I'm trying to part with cause it's 15" and a awesome tone amp...

[@normjacques6853]

People who insist on preserving all of the original components, in an old tube amp of any kind, had better be ready to eventually be the proud owner of an all-original, perfectly-preserved PAPERWEIGHT!! Nothing lasts forever...especially capacitors! No matter how skilled a technician you may be, you are not going to surgically repair a faulty cap...or resistor, etc. I honestly don't know what these 'purists' are thinking. I love old amps but, personally, I prefer an amp that actually works!! Modding one to make it quieter, to me, is a major bonus!

[@michaelneal900]

Hey have you ever seen a Gibson Maestro? A friend of mine had one. Small amp. Totally rocked.

[@roscoefoofoo]

As always, interesting and well done. Thanks!

[@TheGuitologist]

Danke, Roscoe.

[@roscoefoofoo]

You're quite the modern Renaissance Man, dude. Your playing is as impressively soulful as your problem-solving is sharp. You got the muse and the logic both. And as much as I love vintage Fenders, you also do a great job reminding people that amp history is richer and quirkier than just Fenders. That said, I hope you'll post more of your playing on rehabbed vintage Fenders!

[@SqueakerAlpha]

just out of curiosity what does it cost to change all the capacitors on the board ? dont you connect the shield tape to ground ?

[@dmorris2587]

I have a 1965 Deluxe Reverb. It has been recapped and a grounded power cavle added. No regrets. I want it giggable not just to look at. But it is also just cool to look at.

[@CrimFerret]

Keeping it original might have made sense if it wasn't going to be used, but it would have been a shame for it not to be used as good as that sounds. It needed the overhaul. Gibson didn't design the circuit boards to be pretty, they were designing them to to perform the function and used the components they had available at the time. The way I look at it, if they'd had access to the quality of capacitors we have now, they'd probably have used them. You kept the circuit working as close to intended as possible and that's what really matters.

[@TheGuitologist]

Thank you for the comment. We are in agreement.

[@MarkTillotson]

Perhaps adding a high value good cap is series with vintage, possibly leaky, caps would allow the originals to stay in place with the modern cap stopping any leakage (ie you remove the large dc voltage from the old caps, possibly slowing down their deterioration in the process?) - just a thought...

[@michaelkassner5082]

I know this is kinda late, but I've just joined. I love that epi! You are not shotgunning when you change electrolytic caps that are a half century old. Using new (as opposed to nos) is wise also as these caps can dry out just sitting on the shelf. Also, older electrolytic don't have the safety crimp and make a really nasty explosion under some circumstances. BTW, the logo looks like the ugly hunk of plastic the put on the headstock of some of their guitars. Still, you could do a lot worse for the money.

[@danielsperry8114]

Great video Brad , the guitar riffing at the end was the icing on the cake and i could listen to it all day . Brad have you ever done a video on " how to use a variac to get the brown sound " ? I've heard that a variac can damage your amps transformers and tubes ? I'm not an amp tech just a guitar player . Thanks for any info ....

[@TheGuitologist]

A variac? Damage? Nah. If anything, you're running everything much cooler. Your tubes will last LONGER run in this mode. Some people will repeat anything they read, and one of the hysterical things that gets said is running at low voltages will cause "cathode stripping", but this is just BS. But anyway, no, I have not done a video on using a variac in that way. There are so many better ways to get overdrive these days, I would sooner recommend just buying an amp designed to get that sound out of the box, or modding something to get that sound.

[@danielsperry8114]

Thanks for the quick answer Brad !

[@TheGuitologist]

Thanks for watching, Daniel.

[@cantyouhearmeknocking1961]

@@TheGuitologist Now you can buy an EVH 5150iii 15 watt lunchbox amp & get just about every EVH sound. Cool, EXTREMELY high gain amps, but no clean channel to speak of. No variac needed..

[@australier263]

Awesome sounds great after shielding! Good job done! This is a killer Amp! Only thing I would miss is the reverb. But better not, than a sad one!

[@thats2kewl]

Another great video...that amp sounds awesome!!! Love Epiphone stuff...the poor man's (me) Gibson! They still use that emblem on some guitar lines. What a PITA have the caps under the board...what were they smoking when they designed that?!!? Lastly, I was wondering if maybe that orange drop cap by the input was causing the noise..."Mr Carlson's Lab" put out a video on how these do have a preferred direction of installation...have you ever experienced this? Thanks for all the great knowledge you share with us!! :)

[@TheGuitologist]

I'm aware of that video and the concept of outer foils. In this amp, I did observe the foil polarity during installation, but for the most part. a well shielded amplifier won't matter whether your install signal caps backwards. Modern caps are usually smaller than their vintage counterparts anyway, so the surface area is lessened (smaller antenna). And unless the amp is just designed on the very edge of stability or is high gain, like a Trainwreck or Marshall, the polarity will be negligible. Shielding is the real key. That and lead dress.

[@thats2kewl]

The Guitologist Thanx for the reply. I saw that video a few weeks ago and, after beging aghast by what he showed, took a bunch of new caps to the scope... couldn't reproduce his result...it didn't make a difference which way they were placed, same small noise signal from touching them for both directions.