SERVICE DENIED! The Weirdest Guitar Amp I've Ever Seen and Refuse to Fix
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- Опубликовано: 27 авг 2017
- Here's one that I have refused service on due to some very BONKERS building techniques. This thing has more boards than a surfing convention, more connections and plugs than a middle age dating party, parts from virtually every era, and on top of everything, there is NO SCHEMATIC. This won't stop us from opening it up, gawking at the freak show, and having a little fun at our own expense.
If the builder sees this video, I hope he doesn't think I'm being mean, because I am not. To be perfectly fair to him, it is likely this was a build designed to consume some spare parts and be creative with what was on hand. This appears to be a frugal build, which I admire. This build is simply outside my ability as a repair person to service without spending so much time tracing out the circuit as to render any attempt at repair uneconomical.
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I'm the builder, but in your position, I'd refuse to work on it, too! There were many reasons for the build turning out the way it did. Too many to list in a youtube comment. It's basically a Fender front end, and a Gibson power output section. Many of the choices were due to the availability of components back in the 1960's. And, no, I don't have a schematic after all these years.
frettedfun never know when someone is kidding, but if this is indeed your build, no offense intended.
No offense taken. Your analysis was very entertaining. When I built that amp, I was learning as I went!
So was I right...did you disassemble a 66-67 Gibson amp and steal the output and tremolo circuit ideas from that?
No, I did not disassemble any amps. I had a paperback book that had a few schematics in it, and used those to build my own. Keep in mind, this was before the internet, and schematics of commercial guitar amps were really hard for the hobbyist to lay hands on. Also, about the only parts stocked by the electronics supply houses were those used by TV repairmen. (Yeah, they really did repair TV's back then! LOL) Are the output tubes still the original 5881's? There are two separate chassis because I couldn't find one that was the right dimensions. The tremelo circuit was added after the amp was completed and had been in service for a while. It looks cobbled on because it was! It was like trying to put five gallons of stuff in a two gallon bucket!
Building one's own amp these days, with schematics, kits and how-to videos overwhelmingly available, is challenging enough. I cannot imagine doing so in the 1960's, while even Leo Fender was still perfecting his designs as fast as James Marshall could copy them. The fact that your hand-built amp is still around fifty years later deserves a round of applause, and a performance of "Eruption." In this future world of 2017, a little knowledge is a dangerous thing indeed when anyone can read Wikipedia and watch a few RUclips videos and proclaim themselves "tech."
I built this back in the 1960's in my basement. Pleased don't be too harsh, I had little money, not many tools, and needed an amp. I gigged with it around the Dayton, Ohio area for years. It worked pretty well, but it sounds like a lot of the components have failed after laying around for fifty years!
I thought you were joking when I first saw your comment. It's good to make contact with the builder, John. If you watch the whole video, you'll see you did get props from me for being resourceful and frugal in your build. It's an admirable quality. Have you built any other amps or electronics gadgets since?
No more amps, strictly acoustic instruments now. You could say I learned my lesson on that first amp! LOL Got a few RUclips videos up under the Frettedfun user name.
That's really cool, John! Any of your guitars in the videos?
frettedfun it’s a shame that «the guitologist» spent so much time moaning and so little time doing basic fixing, so I can only conclude that unlike you, he doesn’t have the nuggets to do any real work
@@Ideal1980 yes true, 1980 was an ideal time to .....buy parts.......have access to more schematics......and live a simpler life allowing more time to spend on this thing. Please fix your way back machine, go back and remove the massive chip off your shoulder.
This video was awesome, mainly for the fact that the original builder came forward in the comments and explained it's origin. That's why RUclips is so great. It has informative interesting videos AND solves little mysteries
RUclips is great and I actually wanna find the owner since he is in my area and just have a talk he seems nice. But the thing I don't like about RUclips is everyone who hasn't done shit in this line of work who thinks they can do better than the video maker
Drop some LSD and it will make sense.
If I did that, I'd get lost inside this amp and never come back. Maybe I'd find John in there too.
That's one way to get 'into' an amp "...one pill makes you small." Ask Alice.
hahaha
Perhaps LSD could stand for Loose Solder Demonstration?
Best comment on this video. Aside from the guy who actually made it.
I'm going to respond to a lot of similar comments here in a sticky... I see the "I'm a better tech than you" brigade is out in full force on this one. My guess is it made its way onto one of the forums where the pot shots are flying fast and furious from the peanut gallery. There are several reasons not to get into this amp...
First one was mentioned extensively in the video - the build quality and layout are an issue. Even if I trace out the signal starting at the input and working my way through, virtually every solder joint in this thing needs a retouch. I uploaded this in 1080p, so even from the lofty heights of Mt. Know It All, it should be at least somewhat evident that the soldering on all those split terminals is slapdash, so even if I do manage to get it going on the bench by finding the immediate problem, the chances of it coming right back to me in a week after its first bumpy car ride are fair.
Second reason not to touch this thing with an insecure troll's 18-inch butt plug was not mentioned in the video, but is very real - liability. In fact, this is so important, it should have been the first reason. If I work on this thing and send it home with the owner and it burns his house to the ground or electrocutes his toddler the first time she sticks her hand in the rear end, I'm fucked. I know it's hard to fathom such things as liability issues from the comfort of your mother's basement, but it's very real. If I sign off on this thing, In the eyes of the law in some states, I OWN it at that point. Granted, not all future issues belong to me, but anything I miss that is a danger, i.e. 75% of the build in this case, including the floating PI and tremolo boards, could potentially come back on ME. The fun is over at that point. No more repairs, no more "Guitologist", no more videos.
The third reason for me not to touch this with your grandmother's purple vein dildo is, it's possible, maybe even likely, this thing has already been serviced or modified by someone else in the past, especially if it's as old as I initially suspected. The power caps and some of the other caps appear to have possibly been replaced. If that's the case, I'd be at least the THIRD crazy person to have worked on this thing.
Fourth reason not to touch this with your dad's red rubber gag ball is there is no schematic. Being a one off, custom job, and with the boards stacked and parts of the circuit totally obscured, troubleshooting could be complicated by the fact I have no idea what to look for, other than generalized guesses of what I think SHOULD be there, as in something you'd commonly see in a Fender, Marshall, Vox, Gibson, whatever. If this guy was pulling out all the stops and getting creative with this circuit, I would not know it until probably half way in and by then I would have already wasted time on it. Those of you saying "you don't need a schematic, pussy" are technically correct, I could trace this out and draw a rudimentary schematic as I went and eventually find the problem, but that still doesn't get rid of reasons 1, 2, or 3.
Fifth reason not to touch it with your sisters favorite zucchini...regardless who built it, unless it was Howard Dumble, Ken Fischer, or Jim Marshall himself, I do not believe I could accomplish a complete and thorough service on this - one I would feel good about - without costing the customer a significant percentage of the amp's actual market value, i.e. it's an uneconomical repair for me to attempt. He would be better off from a monetary standpoint to sell it as is to a hobbyist.
On another note... At about 20 minutes into the video, I mention that I think the builder probably disassembled a Gibson amp from the 60s. The reason I said that is, there are some caps included one would find in a 65-67 Gibson, and the OA2 tube was used in some Gibson designs of this era in, you guessed it, the tremolo circuit. In fact, the Gibson amps that used such a circuit were also the kinds of builds that left one scratching his head. The GA-35RVT Lancer is one that springs to mind. I've owned a couple of them in the past. That amp included not only an OA2 tube in the tremolo, orange Sprague caps, and split terminals on the board, but it also had 7591 output tubes.
My first thought was that some of it looked like my RVT! In motorcycle parlance I'd say "looks seriously hot, but that ain't for the street, you can't take that to the dealer for service!" As to the comments, well, that's youtube! LOL! Good job on vid and comment!
The Guitologist I couldn't agree more. There's two things indeed, the efforts and risks concerning yourself on the one hand, and your responsibility to others on the other hand.
Ok, I'm one of the people who called you out Brad, I didn't get directed here from a forum or anything like that, I really do just watch your videos for some amusement.
You seem awfully butthurt over some criticism? Piece of advice, which I'm sure you'll ignore, but it's usually best to ignore negative comments than to inflame the situation and "feed the trolls". The choice is yours whether you take the criticism on board, or ignore it. Trying to justify yourself in the comments or a following video just comes across as narcissistic.
I am fine with criticism when it's respectful and considerate, which the vast majority of criticism is on my channel. I love a good discussion and debate. Some of the criticism gets nasty for the sake of being nasty, or for the sake of dick-measuring and ego-tripping. This is the part I find amusing. I don't mind feeding trolls because trolls bring heat, and heat increases hits. So at some point one must ask who is trolling whom?
I dont know why i'm suprised that there are just as many dicks in the niche world you're in as any other. I'm a naive optimist? Never been one of those before- that said, you should refrain from complementing those dicks by implying that they're admirably sexually adventurous.
welcome to old ham radio tech. called ugly construction, and consolidation technique. try contacting the ham radio club in your town, and look for the oldest geiser there. It will make perfect sense to him. Trust me.
I can agree with this. The sad part is, after restoring a lot of very old broadcast radios and ham rigs, I think I am becoming one of those geezers. During this video, I felt myself understanding what and why the builder did what he did. >.
I get it perfectly. It was built for the purpose of experimentation and for the use of the builder, using the parts on hand.
Watched this with my neighbor I grew up next to. Recently retired engineer with GE's jet engine division, he's big in ham radios and a great guitar player with every piece of equipment he's owned since he was a kid. We're watching and he's explaining the how-and-why's to me. Great time!
Those old school radio amateurs built their equipment just like that. Tubes and all. Find one and ask for help. Why not? You really don't want to spend a lot of time, here. Maybe a radio guy wants to make it a repair project.
Boards mounted on top of one another, you say? Maybe the guy did recent design work for Mesa or Marshall? 🙃
Check out the onboard effects modules for the late 60's Vox guitars, my fav is the Ultrasonic.
All bullshit aside. For a guy to take it in to have it repaired, it must have sounded amazing.
In the 60s the RCA tube manual had modular designs for circuits such as power amps , preamps , tremelo.
The amp equivalent of the Winchester house.
EXACTLY! Avoiding going up some stairway dreamed up by a madwoman to fool ghosts was the idea here. You nailed it with this comment.
Jody Parsons nice
John Holbrook seems to have a impressive
resume "John Holbrook began his recording engineering career in the 1960s at IBC studios, where he worked on masters for The Who’s “Tommy” and Jimi Hendrix’ “Electric Ladyland,” among many others. He has also worked for analog synth manufacturer EMS, designed several well-regarded recording rooms in New York, and maintains an active freelance engineering schedule.
Holbrook’s work has earned him five Grammy Awards and innumerable gold and platinum albums for work with such acts as Natalie Merchant, Elton John, The Brian Setzer Orchestra, B.B. King, and The Isley Brothers"
Interesting stuff.
"citation needed"; that part about the recorder.
duncan rmi It looks like we found a fellow Wikipedian!
Buddy Clem I don't know about the recorder portion but the part I posted was from an article in a studio engineering trade journal Holbrook was on a 3 person panel discussing studio monitors and that was an excerpt from his bio. As I was quoting from another's quote with no footnotes a citation seemed pointless it was only intended as a possible point of reference or origin
Sorry guys, that was a different John Holbrook. My background includes appliance repair, welder, electrician, shop foreman, estimator, musician, and cemetery maintenance. Now retired and loving it.
This video was absolute gold. All of the video references were great, and tying 'Centerfield' in to your 'left on the bench' line was genius! And then "Dear future repair man, first of all, sorry!" Thanks for the laughs this afternoon.
The inside of that amp is like a Tool video.
Swiss Army Knight HAHA yesss
So, it's nonsense
🤣
This was a gem of a post. First time in a very long time that I read deep into the comments section. It revealed a great story with plenty of character and characters.
This is one of my favorite vids on your channel. Knowing that John built this as a kid is amazing. I would be proud if I had done it, and would love it As part of my collection. I’d be careful as hell using, but love it just the same.
I might be weird but I’d be super excited to get my hands on a unique one of a kind amp like that. Bringing that thing back to life would be rewarding as hell!!
I've got a 1940 radio I'm gonna patch my guitar into its all point to point 😂😂
This wouldn't have passed the sniff test by Rusty of Uncle Doug fame. He most likely would have lifted a leg up and urinated on it. Rusty had his shit together.
Then Jack the cat would have defecated on it.
movinginstereo40 Had?
That's good news I miss uncle Doug and the gang
Ditto
W/O a schematic, glad that you let it go......I miss Unkee Doug and the gang also !
Hello. Well, it looks like a lot of thought went into it anyways :^) Those "Black Beauties" with the red printing are "DIFLIM" capacitors, and usually are fine (very low leakage). The "Black Beauties" with yellow printing *are full paper,* and need to be tossed.
Thanks for the comment. I enjoy your channel. I've had several instances in memory where a red labeled Sprague .2 or something was faulty in a tremolo circuit. Soured my taste for them generally, and I've grown to consider all old Spragues suspect, but you may be right, they probably fare better than the orange ones, and Bumblebees, which are never good for leakage above certain voltages.
id be taking the reverb and tremelo circuits out for starters.then get to work on the basic audio amp
got a suggestion; buy it from the current owner. then fix it properly with the help of mister wizard paul carlson, clean it, make it look nice and send it back to original creator in a gift wrap. at the age of 77 that would probably be the only surprising and best gift for him. also -no offence- you would learn some on the way since you are not the best tech around. creator/owner would be happy, watchers/us would be happy, you would gain respect and experience win win win.
Hey! Mr Carlson's here and the original builder posted too. What a great video.
Sounds like a cool Mr Carlson's lab rebuild..
Half looks like the guy was prototyping for a modular preamp design. Interesting
Very possible. He's a misunderstood genius.
as i'm I
Aren't we all ? :D
I agree with you. The guy builds Marshall clones, which this isn't. Very interesting bit of video. I'd have been more excited by it I think.
@@GavinMorris1 Same, I'm sort of impressed by all the shielding, discrete preamp, twisted pair wiring, thoughtful placement and orientation of components trying to minimize inductive coupling. Clear that it was made in the 60's with off the shelf parts, partially recapped already in the 90's, and refined along the way probably by multiple different techs, likely as their own personal amp; the whole thing seems like a labor of love.
I bet it would sound pretty great after just reflowing everything, new caps and maybe some new resistors and tubes, probably wouldn't even need to think about how it actually works if you don't want to. But then I imagine some guy probably asking "it's gonna cost HOW much???" and then I totally get where he's coming from.
Now for a real nightmare that I wouldn't want to work on even if somebody wanted to pay for it - Tektronix 475. I got one cheap, was going to recap it. Took the case off, took one look, sprayed deoxit all over it, and put the case back on, never to be opened ever again. Looks like somebody put all the parts into a bucket and shook it until a scope came out. Apparently some people think those things are beautiful works of engineering; to each their own I guess.
John Holbrook is a recording engineer. I thinks he's won a few Grammy. He's recorded some big names. And he's still active and listed in LinkedIn. States that he's in Albany NY. Ping him and see if that rig is his.
www.prosoundweb.com/topics/studio/noted_engineer_john_holbrook_selects_klein_hummel_o_300d_monitors_for_his_p/#
macgyver77777 .... same guy. www.linkedin.com/in/john-holbrook-39a26032
He engineered a lot of 1970s Todd Rundgren and Utopia records and Roger Powell's "Air Pocket" who was the keyboard player in Utopia and I think played guitar on Roger's record on a few tracks.
Brad, did the new owner of this thing try contacting this John Holbrook again? Did you? I would use that LinkedIn page to see if he remembers this thing. I think it would be worth the time and effort, if it did turn out to be his. You might be sitting on something really innovative there, musical history too.
WhoWouldWantThisName .... He's picking at it hard, but this is what the inventing process looks like. I used to hang with a mad scientist type. All of our stuff looked like this. We'd get a working model and start looking for capital.
I've cobbled together a few frankensteins in my day and I always worry about future service guys being able to deal with it. I always stick a schematic in the chassis but some that have come back my way had their schematics missing, I know I put one in there but there's no accounting for some peoples carelessness.
That's possible too.
Nearly lost me there at 8m30s but then the comedy clips reeled me back in.
"...I've got a big ass..." ha ha ha...
It's a RAT ROD amplifier.
+ned ROFL, yes, and even the rats have moved out.
ned after watching all of it I think your right.
absolutely if I see a Cap rigged and hanging and shittt...that is rat rod lol
See if you can make it through airport security with that ?
John Holbrook was a British sound engineer who did live sound for Paul Butterfield and Todd Rundgren's Utopia concerts. He was also with the Bearsville Studio where he engineered sessions for Peter Tosh among others. At some stage he worked in London for EMS, a synthesiser manufacturer. He also played in an obscure band called Baba Sholae with Frenchman Jean-Yves Labat.
Don't think this is the same John Holbrook.
Why is that Paul?
The comments from the man who says how he mase the amp, do not seem to match with the history of the sound engineer who had Bearsville Studio. @@bradleyjorgensen3541
The funky 3 and 2 pin plugs are known as Jones connectors. Very popular in the 40s and 50s.
they reminded me of the heathkit amp build from radio shack in the 70's
I swear it looks like he breadboarded each circuit and then figured out how to cram 'em into a box.
Why he didn't just PTP this, I have no idea. Had he just done that, I would have worked on it.
Looks like a self-dare...
" The Guitologist
The Guitologist
4 days ago
Why he didn't just PTP this, I have no idea. Had he just done that, I would have worked on it. "
I'm glad to read that comment, I might retract my other comments as my beloved Cornford is a point to point and now Cornford are out of business my worry is getting someone to repair it in the future (although several years of gigging and rehearsal all I've had to do is replace the power valves, and tighten some sockets and switch nuts).
Looks like the "remote" 8-Track amp in the back of a 1974 Gremlin!
I'm glad that I saw this video. Now I feel much better about the "custom" job I did on my buddy's Bogen CHB 50. Anyway, your channel is great and is a real service to the amp repair/DIY enthusiast. Keep up the good work!
as soon as I saw the opening image .....I instantly gave you a thumbs up !!! lol .......and then after seeing the
real creator show up and take responsibility .......coolest ever video !!! Kudos to FrettedFun !!
I once saw a piece of lab equipment where the manual actually said "Be very careful when the capacitors are charged. It can kill several people at once." This gives me the same feeling, kind of.
Very cool video. It reminded me so much of my electronics class in high school in the early 70's. A lot of equipment looked like that albeit not as crazy but close to it! Great vid, TYFP!
I lost count of how many times I said "what the hell" watching this video. What's really scary is you managed to keep me glued to the screen for a half hour watching this!
I recommend denatured alcohol for that adhesive. :D
You call yourself a professional and don't know what that is ! John Holbrook is renowned for inventing the first valve powered food processor in 1908 ! The input is to feed ( thin ) vegetables into, not for a guitar ! I would never bring any of my kitchen appliances to you for repair
hahaha. It's just as well, the only kitchen appliances I fix any more are these: ruclips.net/video/mMMQPTd0DHE/видео.html
Lol.
Ha Ha just for fun: Clicked the link. For a minute I thought you might have meant to post a link to the "#@@%&^" that caused all the carnage in Dallas 1963. P.S. Like your stuff.
mike fear : All in good fun here goes. Guitologist calls himself a professional and could ALMOST CARE COMPLETELY LESS about what it is. Ever experience an unexpected 400V or so shock from something like this? How about EXPLODING ROTTEN ELECTROLYTIC CAPACITORS? Ever had one go off IN YOUR FACE? I could go on. Dare me. Again, all in good fun. Be sure to put the lid on tightly and observe polarity on your vintage processor.....
Lol
I would have been scared to plug it in and turn it on. Let alone hook a guitar up to it and wiggle stuff in the back! You have way more guts then I do!
Guts = code for male stupidity
Glad you changed your mind to check it out, it was informative. You, your knowledge and willingness to.share is all the production value I need, I almost baled before you got into it. Thanks for the vids!
Thanks for letting us look inside, man that thing is crazy looking
The Frankenamp with more buzz and hum than an angry wasps nest, looks like a black beauty but kicks like a mule. That is a junkyard amp, love it.
Looks like something I might have built 40 years ago and then now open it up and can’t figure out how I built it.
But you know you really want to try make it work again just to see ( and hear )
And on this exciting episode of Scrap Heap Challenge... 😜
Well, I’ve watched a few of your videos and... you’re pretty cool, and very good at this stuff. Ok, I’m a Subscriber. Isn’t it a trip the builder saw this? What a cool conversation.
Must have been surreal seeing this thing resurface on RUclips
If you want to really see a freak show I've got one for you. My father in law and I bought some Navy Surplus shipboard Oscilloscopes for $15. Cheap enough, right? But they ran of 480 cycle power so they would run off of houshould AC. He built a power supply for me that looks like a birds nest, with parts left over from the 40's on up to present day electronics. Although he had it running on his bench, I'm afraid to plug the thing in. I would rewire it if I had a schematic, but he didn't take the time. He was an electrical engineer and did work on the Gemini program for NASA and helped the Navy develop surface contact radar to hunts Nazi subs during WWII, but there was no rhyme or reason to anything in this power supply.
Genius marches to the best of its own drummer.
Have you read John Elder Robison's book "Look Me In The Eye"? He spent years maintaining and re-inventing all kinds of weird equipment that belonged to Pink Floyd production company. Also he innovated and invented much of Kiss's crazy stage effects. Fascinating book.
Haha you're sound effects and clips had me thrown enough to not realize I was watching a commercial for like 30 seconds🤣
I absolutely love this story ! Even my wife who know nothing about electronics loved it from a human interest POV . Thank you Mr Holbrook. : )
I like how it's screwed, bolted AND welded together. This build must have preceded the widespread use of hot glue.
Richard Hunter it'd survive a nuclear blast... The cockroaches could jam with it
That's like a trailer hitch electrical connection. Good times
THAT"S IT! I was racking my brain trying to remember where I'd seen that very connector, and you're right, it's a trailer hitch electrical connector for the tail lights.
The Guitologist
I just hope you checked to make sure the brake lights and turn signals worked after plugging it back in. 😎😎
Lee Jacobson that's right! Wow, that's just... Yeah
Robert Hathaway don't spoil the fun. We were gonna hook it to a camper
Molex has standards for connectors that are used in automotive, computer and industrial systems
Question. In a previous vid of yours I watched, you said the Sprague Black Beauties were usually pretty good compared to the bumblebees (it was the dual Gibson amp video), yet in this vid you stand something to the affect that the Spragues were usually not too good in old amps. Which is it? I usually leave mine in, but now I'm wondering. I always replace those old Fender blue or brown caps though, they seem terrible after a few decades.
Interesting video, wouldn't even know where to start on this one, plus the liability and likelihood of bring backs is insane.
What is the name of the song at the end of the video though!? Going to drive me nuts till I figure that out.
I think this is an interesting piece. John Holbrook has an extensive career in audio. I guess I would have at least checked the tubes and re-capped it and see "watt" happens. It could be a very good design. Diamond in the rough?
I think your missing a flux capacitor to make it work.
Just stuff a little class D amplifier module in there somewhere and hook the filaments only up for nostalgia. Stick a fork in it, call it a day.... drink a beer.
You know what they say about people that cuss a lot... theyre telling the truth & aren't fake. I'm in. Subscribed. Your videos are first class bro. Good shit
Offer the owner a fair low price and keep it to work on at your leisure. Would be a satisfying challenge to get it working again. Especially if it turns out to be a piece of rock history. I would definitely contact Holbrook to see if it was his creation.
The rock history thing is probably overblown, but I think you're right that it might be neat to work on as a hobby project, i.e. not a paid gig. I could more easily justify delving deeper if that were the case.
Is it possible that someone had worked on it before you? Those new caps, along with the VERY old ones make me wonder if someone more brave/stupid than you tried to diagnose and fix things before you got a hold of the amp? If that happens to be the case; you'd at least have a couple quick points you could test for current. I think a lot of us want to see you prevail against this riddle wrapped in a mystery.
VoxPathfinder15R ... Now thats fuckin funny. Funny because its so true, plus im past 40. So...probably even worse.
VoxPathfinder15R ...yea...but when you get those young ones with daddy issues or whatever reason they hook up with older guys,it gets even spookier. As in, I may not even be the first species in here,let alone the first or second.....guy. 😂 ha ha.
You know, I like the consistency of your comments. Not necessarily the content, but moreso the delivery. Very entertaining.
My thought exactly... Either somebody figured out how this build works and changed a few caps or an amateur simply changed a few caps in the hope that it would fix that thing. I voting for the second option because why would anybody who know what he/she is doing leave decades old caps alongside with brand new ones... It doesn't make any sense. I seriously doubt that this thing ever work... If it did, it probably didn't sound very good.
Sweet video! I love seeing others do this type of work.
Brad good morning sir I have a question regarding building a tube amp, what circuit is the easiest for a beginner to complete successfully?
That's the Fred Sanford Amp. haha
I'd throw in for crowd-funding on this thing. It's going to kill me... I have to know...
maybe put in a link to a kickstarter?
otherwise... great video. I've watched all of them and this is the first time I've just *had* to comment. keep it coming!
Awesome idea!
I'm with Brad in this one. I wouldn't have tried to repair it either. I could scratch-build an amp with a serviceable layout in less time. But, thanks for opening it up. What a trip!
Best morning show EVER!!! Thanks for the first thing in the morning laughs!!!!
I eat your videos like candy. You almost have it working. Keep going, have fun playing it while it burns to the ground. Most importantly keep the video equipment charged and filming it. I really think this is a test.
It's a test all right...a test to see how risk averse I am.
what - no effects loop
Those plug connections remind me of old pinball and arcade machines
I know from my own experience in repairing and restoring old radios and other vintage electronics, that you made the right call. The modularity idea is fine, if executed properly, which it is not in this case. Of all the things that should have had a connector and socket to the chassis, that control panel on the front should have had one, but it was hard wired in so you would have to remove it to get the chassis out. By the way, the funky plug with the flat blades arranged perpendicular to each other is called a "Jones" plug, and I think you are right, Webster Chicago used them on some of their equipment such as wire recorders.
You mentioned in the video that the fellow that owns this bought it from a man with an English accent, if that's the case, and the man was the one who built it, then that explains a great deal. Many British radios had terminal boards under the chassis, much like this amp has, sometimes with components attached to both sides, but at least in those you can find the paperwork, and they used proper terminals, not silly loops of wire on a piece of perf board. Why didn't they just use point to point wiring with terminal strips. That power amp chassis even has extra holes that must have contained tube sockets at one time
I used to go to auctions held by the local Ham radio club and pick up a lot of home brew equipment like this, I ended up parting most of it out because it was so crudely constructed, built out of used parts from multiple eras, or beat up, and of course with no schematics or paperwork. In my opinion that's what should happen to this thing, the only way to get any of it to make sense is to gut it and start over, which is totally out of the question at shop rates. A home brew amp is still going to be a home brew amp, with minimal resale value, even when it's built properly, so a wiring nightmare like this is really only of value as an organ donor.
Probably a build from a organ. In 20+ years of tube collecting have never seen 7591A's with a exhaust tip. Those are super RARE..
Fendernirvana I've seen them before, but you're right, not often.
I've seen those connectors in vintage equipment such as console stereos... Amp tech since 1965...
Most of these trolls miss the point that you do this for money. I doubt your customer would want to pay $1200 labor plus a shit-load of parts to restore a $100 amp head. All the "you should have" and "why didn't you just" crowd obviously have plenty of time to dick around but I imagine not much money because of it. Replace one thing and it would turn into an avalanche of parts and fixes on a cobbled together amp like that one, I wouldn't have messed with it either and I have 40 years experience.
Hello there!! Have seen a few of your "S-P Fridays" in the past, and so recognized your channel when I stumbled across this vid while searching 'bass amp repair'-- (not a lot of them, so PooTube threw in those that just matched 'amp repair'!!) -- At any rate, I had a question regarding the possibility of 'shoehorning' together a bass amp, when *lo & behold*!! You test out the Holbrook Hellspawn on the *exact* 4x12 Fender cab I plan to use for my build!! So, with that as the start, I'd like your opinion on my thoughts as to the viability of my plans for a homebuilt GMO bass rig ['GMO'= Get More Ooomph'!!] -- After loading the cab with subs such as are used in 'booming' car audio, rated at *least* 500~800w, could I use a car audio subwoofer amp to drive them (voltage supplied by a repurposed 450w PC pwr supply for the 12v DC)? Front-end duties would most likely be handled by either a floor-based preamp/effector such as a BP-355 or a half-height rackmount Rane or GK or Peavey instrument pre that would be fitted into the cab itself, either rear-facing or top-mounted with knobs looking up...... And, I assume that such a setup would allow me (thru the threshold & output controls on the 'brick' amplifier) to dial *down* to have a 75~100w rig for small spaces *or* "wink, grin, turn it up to 10!" for a 500w+ rib crusher for outdoor venues, etc. (??) Any insights you might have would be *greatly* appreciated!! Blessed Be, & Peace!!
You forgot to mention your Aunt Agatha's lacey strap-on ;-)
Anyway, that perf-board construction is bizarre. That's the kind of thing ETs do when they're building a prototype - definitely not for a final production unit. Looks like this guy knew just enough to be dangerous, literally.
The best part of the amp is the "Custom built by" label.
"Dear future repairman, .....sorry. Here's the schematic..." This killed me! Very interesting video! I thinks it's brilliant to put together an amp like this out of old spare parts!
Ok I watched the whole video and it was very interesting to say the least. I nailed the homemade part of it Knobs were a dead give away .
I come from electronic family and I used to own a 2 way repair and retail shop for almost 12 years......
When you first took the chassis out and showed the underside of it I thought it was made by an old family friend of ours In Abbeville, La. He used to build guitars and amps on Concord St. He rented a upstairs room above a lawyers office. Very good electronics tech. The old fashioned kind like I grew up with.
Watch out for those caps They can kill you in a heartbeat ~!~!
Plus Tard from Cajun Country ~!~!
Thanks for the comment.
I also subbed you I love these types of Videos ~!~!
I built an amp for my bass that looked a bit like this, was the best amp I ever used till it got stolen. Beware appearances
You’ve got to be joe king
WOW! Holy Hell!! Must have been built by a mad scientist! Or some one who was just plain mad!
Again, I stress this highly, no offense to John, but he was clearly off his meds the day he built this one. This is Dr. Frankenstein meets Dr. Jekyll.
LOL! Joking aside, it's a shame you could get a schematic for it. Would be an adventure!
Thin line between Genius and Madness :)
I believe the only schematic for it was written on a dining room floor with human feces but I can not confirm that.
It's made by a junior engineer. Everything about trying and minimal planning.
The Molex plug is from an old record changer. They used them in nearly every VM turntable as power for the motor.
Great job and good decision to stay away for all the reasons you stated esp the safety issues.
It reminds me of when i was a teenager in the late 60's and with no dough we made the best of what we could with what we had. I wasn't technical enough then to actually build something like that amp and know i would have been damn proud of it had I.
I think your respectful treatment of the builder throughout the video shows a lot of character on your part. Very nice that the builder actually watched the video and lent his input.
I think it wound have been really cool if the present owner just sent it back to him. I know I'd love to have some of the stuff i built back.
Bizarre! I parted out an old wrecked gramophone that had lots of unusual interconnects recently. Great to see noddy at the end... runaway! Always loved Mysterious Mr Jones from that period (not going to attempt the typical slade spelling). Hope you're well mate.
You should have entitle this video " Alien Amp Autopsy". I have no clue about amp electronics but I couldn't stop watching!! Thanks for the vid.
I'm going to tap you to title my vids from now on.
I think you call that amp a shitshow. Probably a Princeton Reverb or something like that.
A 7591 Princeton...sounds about right. :D
Would certainly be par for the course.
Awesome video Brad... If its a long lost Hendrix amp, I advise you to keep it just in case... a lot of weird stuff could be done to that rip-off mixture of everything...
It's cool that you found the builder and that the amp survived so long. Hopefully its inbthe hands of someone who has the time to sort it out. Wouldn't be me , but someone would be up for the challenge, i bet !
A cool amp video for the ages !
Wasnt expecting all the cuts around 9 mimutes. Enjoyed it very much
Hendrix’s long lost amp!
Coward. I'd love to take a shot at it. You haven't even mentioned the tube compliment, or tested them. That hum indicates a bad electrolytic in the power section.
And I thought my prototyping system was crazy, holy moly!!! Very odd build indeed
Sometimes it pays to just walk away. The rabbit hole is unending. Thx for the clip.
Without a schematic it will be tough to trace anything and it looks like a rats nest. It probably isn't worth putting the time into it.
generations of rockers will tell the story about the time that Brad let the holy grail amp slip through his fingers. :) naw.. good call!
I just KNOW somewhere there is a piece of this story I'm missing and it will somehow come back and bite me on the ass.
Maybe it's a Prototype Hendrix Amp! Well maybe it's not….
Watchman4u I was actually thinking it was some sort of prototype. I have worked in electronics for 30 years myself and sometimes when prototypes are created you just take what you have and its just the outside of the box and the function or even that it seems to work that matter, whats inside can look like hell but you have something that works for showing the idea/function to a customer. I agree that it looked very wierd though and dangerous.
Stefan: In my limited experience, I would expect to see some sort of documentation that follows a prototyping session. A schematic would be the most pertinent record for duplication/modification/simplification on any further iteration(s) of said prototype. I think the dude just said "I'll have a go at this then, Mate". I do believe it was mentioned in the video that John was a Brit. :-)
Stefan Sjöberg You're totally right.
Love your channel, man!
Any of us that worked in the aerospace industry in the timeframe this amp was built would be comfortable with the layout and execution of it. Simple to figure out, absolutely not! But it is well put together as a prototype. It is in fact, a thing of beauty. It may well have held untold secrets.
I have seen a lot of amps built like this in my high school days in the 60's we could not afford new store built amps,the high school science teacher would try to help out (weird science).
That is called a "Jones Plug"
Thanks for this. Learned something new. Looks like both of those black connectors are types of "Jones Plugs". Good to know.
Do tubes lose power over time?
I have 1965 Harmony h400 and it sounds very weak. It sounds like a 5 watt solid state amp. Is this normal? The tubes are original harmony tubes.
The editing around 9:00 is amazing. Thanks.
I'm glad you had a look at it anyway, show must go on! ;)
Whoa . If you cannot except this one , then maybe Shango can do it . Hand writting analysis ? Maybe it is the famous name ?He might have been the unlucky ones who took the brown acid ! Please do not be offended , but I laughed at your add ons of Floyd`s song money etc .
Shango is just about crazy enough to look at it probably.
The Guitologist Shango66 might but Only Mr Carlson can figure this shit out. He starts with creating your own schmatic (he does for 30s,40,50,)
What's the big deal? It's a cobbled together, fast prototype amp. AvE does it all the time, though not with amps. You see the powersection, from there you have the 2 prong cord for 6.3v glow power. The 3 prong was for B+, gnd and signal. The boards make it easy to switch components and fine tune the thing. You gota experiment when you don't know math.
It isn't service friendly because it never was ment to be serviced. The builder figured he'd keep it forever, or just junk it if he lost all interest in it. Now he managed to sell it, score for him. Bust for the guy who bought it.
I would try looking under the hood a bit deeper. Maybe it's just a copy of another well known amp.
You could always try bypassing the tremolo and reverb. Trying to trouble-shoot another way. Cmon it's simple, not like that mesa with the muting curcuit. Give it a go! It's all lego!
This fix would be much more interesting to see than some mass produced model. Let's see what this guy was trying to do!
I agree with that, i want to see more of this.
Brad was just being a whiny little bitch about this, any tech worth their salt doesn't need a bloody schematic anyway. Sure, the haphazard construction would make it a bit of a challenge, but would also make it a lot more interesting.
I only come here to lol at how crap a tech Brad is anyway, he really doesn't have a clue. Oh well.
well, I kind of got the same impression of "The Guitologist" when he called a Mesa Roadster a Amp Techs worst nightmare... I mean you can even get schematics for those and if you have them, it is quite easy to find the problem.
For THIS thing you do not need a schematic since there is not really a lot in there - you simply need to trace the SIGNAL and find the problem. I'd say half an hour of work when the problem is a "no sound" problem and not a "does not work during full moon when my cat catched a mouse and I farted" problem.
If this is the weirdest shit he has seen, he has seen nothing.
+BavarianMonkey A scope, a signal generator, and lets be generous and say an hour rather than just half to allow for maneuvering that multi-chassis construction around so it's connected but you can actually probe what you need to, and you shouldn't have any problems.
I also found it amusing that at first he was convinced it was 70's construction, but then immediately changed his mind when he saw new components and decided it must have been "new" build from junk parts, immediately lambasting the builder for using old parts like they were the idiot. Like it was not possible that another tech had been in there and replaced the electro's? Pretty obvious even on video that that was the case. He should have been lambasting the previous tech for not replacing the paper in oil/wax caps, that would have been fair.
It's not cobbled together, that thing is a labor of love and passion by some one who probably read some guitar magazines and heathkit and integrated what they could. The parts look like they were installed new if they were used the leads would be shorter. Yes, some of those parts were used in the 50s-70s but they didn't always know back then which caps were bad from the start. But yeah, I was taken in by you trolling us, the audience, on so many levels.
I don't know anything about the inside of an amp, but still found this very interesting. Have to give you a thumbs-up!
Thanks for watching. Much appreciated.
This could be something built by Brian Briggs who worked at EMS Synth, IBC (hence the vague Hendrix connection) and later Bearsville from 1974-1980. Brigg's real name is John Holbrook and he is indeed an electrical engineer. That very well could be some Bearsville/Rundgren/Utopia era frankenstein studio experiment.
Yep, it's looking more and more like that.
If this can be verified, that's pretty incredible.
I really appreciate all these comments about this history and origins of this thing. I already had a level of respect for it as a frugally built monstrosity, but the fact that it came from a 5X Grammy winner is extraordinary. I still don't think it's an economical repair, unfortunately, and there are liabilities involved for me because of the open high voltage and questionable, hurried soldering. I'd have to practically rebuilt it in order to give it the OK.
Could have been as simple as a bad tube... just sayin'.
I always start with the most simple and obvious things like tubes... it's a tube amp after all.
Aw, hell. Just replace all the caps and tubes. Then, see how it sounds. :D
It would be funny if that amp is the best sounding amp ever, after repairs.
You should make him an offer on it, and repair it in your spare time.
Document the process and the result. Could make a great video.
i knew u couldnt resist at least taking a look at it! lol