I just realized I left out an entire section of this repair... I found some old Sovtek MIG knobs in my parts stash from a different MIG I had a while back. I drilled them out and gave this amp a full compliment of original MIG knobs. I filmed that part but forgot about it in editing. Oops. Oh well.
The caps probably weigh more than any other component on the board, so they have the most inertia. If the amp is jostled, they may threaten to break the solder connections on the underside of the board. Those traces are fragile and it's best to do what you can to keep that from happening. Increases long-term reliability. Also, you'll notice I did not de-solder the original leads, but instead clipped them off the old caps and soldered the new caps to those. That kept me from having to disturb the traces on the board also. Too much iron heat and those can just call apart on you.
In russian slang "Sarai" translates to shithole; so the fact that the prefix of the named city is pronounced that way it made that shithole very special!
Aleksey Chernozubkin i loved those amps brother. I sold at least 100 of them. I used to mod them and sell them. They ripped. I wish we could still get them.
I wouldn't doubt it. Sovtek Amps was Electro Harmonix kicking around getting into the amp biz. I figure they have such a big stake in the Reflektor tube plant... why not try.
Yup. It's called micarta. We use it in the tool and die industry as an insulator between high voltage components and ground, or other tools. Usually welding equipment. It's hard, robust, and non conductive. It can also take high clamping force from fasteners without being crushed. They also make micarta washers and hollow rod to insulate screws and bolts from said energized equipment.
On the board too much brown is carbon and does lead to a short circuit. I have found that a sand blaster with glass beads is a good thing to have when repairing equipment, as it allows removal of burn marks on boards so they can be repaired. Also after done cleaning such boards it helps to spray them with glyptal lacquer, and use the clear stuff on circuit boards. That is because it helps make them like new after they have been damaged and this is the only way those boards are easily repaired when a new one is not a possibility.
Why would someone talking about electronics repair need experience as a musician? Are you good at repairing amps? Maybe you shouldn't be playing guitar, then. Your logic.
better than most instructional "how to" videos I've seen in a long time...props on your playing as well. some of us non-book learnin types really pick up quite a bit more info that is usefull by watching a master at his craft rather than sitting in a class listening to some necktie ramble on for hours. very informative and has qued my curiosity wich will promt me to definately watch alot more of your vids..thanks!
Wow, great details in this break down, and repair. I'm sure that was one more happy customer!, and we happy viewers, thank you for the slow rig down with so much details. I learned a lot. And the dive bomb w/o whammy bar was hilarious :D
No L! And you'll never hear me correct about pronouncing again. Because I'm a working man from AL. Dang!! I love your work. The way you talk us through, while showing hands on, is great for me! Thank you brother.
I always establish negative bias supply first.. without it, obviously the power tubes will turn on hard and red plate... Been building hi fidelity tube gear since before you were born, so this is voice of experience. I must say though that you have learned the craft of musical instrument amps damn well and find your vids refreshingly competent, with a nice bit of music tossed in for great fun.
What was the final plate voltage with the -77 grid vdc? The Sovtek 5881's are a 6L6GC internally, they can handle a few more than 19 watts PD. Those Mig 50's are pretty awesome amps. They basically slammed a 2204 and 5F6-A(with circuit revisions even) together, jacked up the juice and sold it for a price anyone could afford. (Wait a minute.....they just modded a 5F6A in reality🎸🤘) Regarding the transformers, I think the manufacturer only had tooling for one style bell for multiple transformers and filled the ends with material that's easy to cut/shape. Remember, we're talking about Russia here. The home of the stamped sheet metal assault rifles and hard liquor made from potatoes. Their shit just works. Another great video! Thanks!
Plate voltage was about 525V. I didn't want to push the 5881 too hard. At this bias, they should last a long, long time in this amp. And it's still loud as piss.
...and you're right about Russian engineering. Their military spec hardware is usually excellent. If it ain't broke, don't fix it. That was their motto. Well, that and "death to capitalist pig dogs". :P
Yes, what they built out of metal usually was rock solid. My dad always tells this joke about Russian engineering: Do you know how Russians build a railroad engine? They take a huge block of metal and just cut away everything that doesn't belong there.
I'm thinking the manufacturer didn't have the equipment to stamp out the cupped metal ends we're used to. Or perhaps that equipment had higher priority jobs. The ends shown there just need one of those metal benders.
I've been a sub for a while I'm just mainly a diy guy. I don't know if you've done like lesson style videos before to teach people like basics for amp repair but I think that would be really awesome I for one would love to learn more. Anyway thanks for the vids keep em comin!
Thanks for the encouragement. I could not do a better job than Uncle Doug. I encourage you to sub his channel for more basic instruction. th-cam.com/users/Stratosaurus1
You do a very good job with this channel. You explain what your are doing and why you are doing it very well, plus you demonstrate the results very well too. I used to be an Electronic Technician in the Navy over 20 years ago and I haven't been involved in electronics in a very long time, but watching your channel has given me the bug to start getting back into it. I play guitar as well, so I might get into amp building. Unfortunately my electronics skills are very rusty, but you have given me the itch to dust them off. Thanks for what you do.
I LOVE comments like this! I do hope you get back into the swing of things and remain interested. Go on Craiglist and find yourself a fixer-upper amp and dig in! A lot of times you can also find stuff in the CL free section for repair. Pick up an old console tube stereo amp or old organ and get your tinker on that way too. When you get up and going, make a TH-cam video and link back here so we can see your progress.
With the nation on lockdown its been such a pleasure watching your vids - one after another! Your content is highly addictive making me fear the impending doom of withdrawal once the pandemic is over. I'd dumpster dive with you any day brother!
Back in the 90's, I always wanted to get one of these. I came so close to getting one, but never ended up pulling the trigger. Despite their fairly poor construction, the circuits are pretty cool and placed in a nice package. it's cool that the Tube Midget was so ahead of it's time, and paved the way for all the little lunch box amps we know today.
Awsome vids,Great info,loved your intro joke,I swear I voted :O on one of those. Have you done in the past or maybe might see in the future a Soldano head? peace.
Nice fix Brad! In Russia, the knobs go to 13 (according to the front panel)! Regarding the transformers, maybe 'folded' sheet metal was a more cost effective solution, than 'stamped' bell covers. As a sidebar, in 1975, I worked for the Canadian distributor of Hiwatt, where CSA required us to rivet metal shrouds onto the Partridge transformers to suit their regulations!
sounds good.... The material you pointed out inside the open transformer ends is a phenolic insulator. They use the same material in High Voltage 3 phase switch gear breakers between the phases.
Very good video. Question concerning tubes and red plating: If your tube is red plating does it always mean there is a fault or could it be just a bad tube? What would it cost to ship a amplifier head to you from Oklahoma? thanks in advance?
Yes, it could be a tube. If it was just one tube, I would have suspected a tube first, but this was both, so I knew it was in the bias circuit. Cost to ship a head...probably around $35-$40. Right now I'm taking a hiatus from outside repairs though. Hit me up around July, I should start taking things in again around that time: bradlinzy at gmail
It's a silicon diode. It was an NOS one I got in some large parts haul a while back. Not sure on the model number. I just checked the voltage rating and knew it would work.
His sidekick Medvedjev is a huge Deep Purple fan, apparently. Wha the Man himself listens to (if indeed he listens to anything at all...), I haven't got the slightest idea.
I have just recently discovered your channel, beginning with the Marshall head found in the trash! I enjoy your repair videos- well done! When you change components out, like pots, caps, etc- do you rewrite the schematic to reflect any value changes?
Cool videos, mate. You don't have any plans to look through a (Sundholm bros. era) Sunn Model-T, do you? Or maybe, a Reval Model-T even? They're made out of Estonia and as far as I can gather, other than how it looks, they're faithful to the original. Cheers, all the best. :)
I really like the tone you got from that guitar/amp/speaker cab combination t ! I'm from Czech Republic and I grew up around these Jolana guitars, since they were the cheapest solidbodies for begginers to get when I started to play guitar (late 90s). I never liked them at the time, but they kinda grew on me. Do you have any mods / tips for this model? I only remember appaling vibrato/bridge system, frets that didn't last even looking at them and horrible open back tuners
I still got a Sovtek MIG 100h. I had some minor issues with it over the years but for the price, it was well worth it. The 1/4" in/out jacks are crap and my bass pot did very little from new. Also had a noise issue that was related to the fact that it was "mishandled" during original transport, that caused the same one 5881 and fuses to blow. The amp tech pointed out the minor damage and was easily fixed. Currently going strong but Its had a bad high input jack for many years that I need to get around fixing. I just don't play it anymore. Good to see that other Sovteks are still kickin'.
Another great video, my question is regarding that whitish substance you are using between the caps you raplaced, what is that and can silicone be used as well?
Fiber glass board is called phenolic,non-conductive etc. Was used by hot rodders back in the day to make carb spacers. Also used in tool and die work at times.
Great video series BTW, i am learning a lot. QQ, for those large capacitors you replaced, did you just cut the old ones out and solder the ends to the old posts or did you completely remove them from the old board? I am currently trying to fix my fender red knob amp and would like learn some best practices... thanks..
I think it's Mica that Sovtek used in their transformers for it's insulating properties. That would be my guess as to what those panels are on the power transformer. See watching them from 5 years ago, every upload watched i have gained some knowledge that i have been able to take away with me. Thanks Brad.
nice work,, its a few years ago i see that , but still good entertaining material, its got to be the most satisfying thing to trace and fix an awesome vintage piece of kit like that then put it through hoops ,sounded damn cool,!
Good video! By the way how does charvel xl 750 compares sound wise to les paul? Is it somehow similar? How do you like that guitar is it as good as people are saying. I have a chance to buy one. Thanks
Those boards on the ends of the transformers were made of a type of bakelite. Iworked in the transformer business in the U.K, around 35 years ago and we used it a lot.
Where did you find that second schematic with all the part numbers included? I've been looking for that forever and all I can ever find is more links to the same original one by Bruce Collins.
We used to have a Sovtek mig100, it was a beast and never had any issues even after years of gigging still running strong! P.S. Love the dumpster vids!
That amp sounds incredible! I´m always amazed at your skills man! i dont know 1/10 of the things you are mentioning but I keep watching (maybe ill learn by watching you haha)
Cool vid again. Love your playing. The fault was a bad connection on the bias diode. When it made contact you got the correct negative bias so the anode currents were correct. When it lost contact then the bias would be 0V dc causing huge anode currents which in turn caused the B+ to drop. Must be a pretty good power transformer because a lesser one would have dropped its voltage much quicker! This amp is a good example of why there should always be a correctly rated slow-blow fuse in the B+, for this amp T500mA.
Great video Brad, as usual. However, I hope you checked the fuse. I had an old amp that i bought a while back, recently checked it because you say it so much and low and behold, not the right amp value...LOL. Thanks man! Bart
I remember an old guitar player mag that talked about these before they were shipped and the article said it was being started by Mike Matthews, who started electro-harmonix.
I’ve been trying to find a demo of this into a new Marshall MX412 240watt. I might just get the new Electro-Harmonix MIG50 “reissue”... Thoughts? I’m new to amp and I don’t know much. I don’t want a straight dirty amp rig since I sometimes play some ambient post-rock stuff and some looping with fuzz. A lot of 70s style spacey prog-rock stuff. I’m playing through an old Peavey 212 Classic that needs some new pots.
I have a Mig100 Sovtek made in Petersberg Russia. I've played it for years gigging in the US. Replaced the original tubes w/ Chinese "Sovtek" tubes purchased in the US. Never had any problems, used also in the studio for recording. This amp is a monster for those who are able to play, it delivers powerful tone and is loud. You must be able to properly set your system, just like any good 100W head, like a Marshall, etc. I love my Mig100 with the original 4x12 cab, I've had this as my main rig since 1998. Sovtek rocks!
When you first changed schematics I saw v1 said 12ax7 but your first schematic said 12ay7. You caught it elsewhere though, those are interchangeable though right( not identical though)? The 12ay7 being less gainy/ less output?
Let's hear some more fat chords from you, through that Stovetek amp. Stove, because it sounds hot! She really sounds much better than the typically fizzy timbre I'm acquainted with from those things. Did you voice it at all?
I bought a Mig 60 new and and Mig 50 at a pawn shop back in the 1990's. They didn't do much for me, but I've learned a lot about tube amps since then. They were a good cheap basic no frills amp. They were in serious need of upgrades as this video points out.
Our "amperage" started to go up. When we talk about amounts of electricity instead of saying "amperage" the correct term for this is "current". Pardon me for making this comment but I think that a good technic like you are should refer to things by their right terms. Best regards and by the way I like the way you work and solutions you have for some problems. Thank you for making your good work public by taking the time to record and edit all this videos. By the way you also play very well.
Old video so I don’t know if you’ll ever see this comment...but anyway, The input power voltage that is switchable from 110 American to 220 European, can a switch like that be installed on most amps? The reason I ask is I have two Redbear MK60’s that are 220V for the European market. I purchased a step up/step down transformer off of eBay to bump the 110volts from my wall outlet to 220volts to power them, but I can only do one at a time plus it’s a pretty clumsy set up and a pain to move around that way. It’d be nice to just be able to switch them to 110V and plug them in.
I really like what you did on this repair! You are really inspiring me to try and build my first amp. I’m a Network Tech building servers, fixing PCs and configuring routers and such. Never really did any electronic stuff. But Mojotone has a few amp kits I’m looking at for my first build. Do you think someone with my background can pull off building a guitar amp from a kit as a first build. I’m looking at the MOJOTONE STUDIO ONE 1 WATT 2-CHANNEL AMPLIFIER KIT. I need a practice amp with low watts so, I thought this amp would be a great kit to start with. What do you think? I would really appreciate your advice...
if it's spelled "Sovtek", why would you pronounce it "both ways"? that makes no effin sense? :P just kidding, awesome videos! i play guitar myself, and love my tube amps, and while i am very technical myself, i would never go upon trying to fix them myself.. i'm glad there are people like you, and even better that you're taking the effort for us to being able to watch you fix this kind of stuff on youtube! thanks!
In Australia the main voltage is nominally 240v but it's often higher than that. Amps with transformers that only handle 220v run hot and break down more often. Combined with the hot weather here the extra heat from running 250v through amps made to handle 220v is often fatal.
Maybe next time you could play a little Scorpions Wind of Change, for the Ruski theme. Nice job figuring out that bad diode push pole board bending business.
I just realized I left out an entire section of this repair... I found some old Sovtek MIG knobs in my parts stash from a different MIG I had a while back. I drilled them out and gave this amp a full compliment of original MIG knobs. I filmed that part but forgot about it in editing. Oops. Oh well.
hahaha....yeah, it's the curse of the observant to be confused by my videos. :P
Just shut up and play your guitar ( through the well repaired amp :) )
You can always upload it again with the left out section included and call it PROOF the RUSSIANS RIGGED this Guitar Rig! - UNREDACTED!!
The caps probably weigh more than any other component on the board, so they have the most inertia. If the amp is jostled, they may threaten to break the solder connections on the underside of the board. Those traces are fragile and it's best to do what you can to keep that from happening. Increases long-term reliability. Also, you'll notice I did not de-solder the original leads, but instead clipped them off the old caps and soldered the new caps to those. That kept me from having to disturb the traces on the board also. Too much iron heat and those can just call apart on you.
Freddy Y, hot melt glue .. ( not silicone) ?
These amps were made in my hometown called Saratov (inscription under input holes says "Made in Russia, Saratov") =)
Very cool. They've made your town famous.
In russian slang "Sarai" translates to shithole; so the fact that the prefix of the named city is pronounced that way it made that shithole very special!
Do you know the translation for the red script word on the Sovtek Mig 60 amps?
Aleksey Chernozubkin i loved those amps brother. I sold at least 100 of them. I used to mod them and sell them. They ripped. I wish we could still get them.
Love the Russian amps, effects and synths. Its also cool to see a tech guy that can play!
In Mother russia, you don't fix amplifier. Amplifier fixes you.
I do not want castrated
@@andrewwagner6851. I do not want Novichoked!! 🤪
"All of the pots are shit", No truer words have ever been spoken.
DeoxIT, comrade. DeoxIT.
Yeah mine are shit on my mig 50, the whole thing needs to be overhauled
@@OutLoudOutLoud deoxit cant save a shitass pot
In mother Russia, Guitar amps plays YOU.
DeadKoby the father land make better amps
DeadKoby some people make clones in America ten times better look up mega tone amp it small amp builder
I wouldn't doubt it. Sovtek Amps was Electro Harmonix kicking around getting into the amp biz. I figure they have such a big stake in the Reflektor tube plant... why not try.
Fender and Marshall copy Rooshki amplifier
KRYPTONITE TUBES !
That brown board is phenolic resin impregnated cloth and they use it for varied purpose's such as a insulator etc.
Also the often sort after and very misunderstood material that was used on the neck pickup of Eddie Van Halens original Frankenstrat.
jon lennon Micarta is what it's commonly called.
Yup. It's called micarta. We use it in the tool and die industry as an insulator between high voltage components and ground, or other tools. Usually welding equipment. It's hard, robust, and non conductive. It can also take high clamping force from fasteners without being crushed. They also make micarta washers and hollow rod to insulate screws and bolts from said energized equipment.
On the board too much brown is carbon and does lead to a short circuit. I have found that a sand blaster with glass beads is a good thing to have when repairing equipment, as it allows removal of burn marks on boards so they can be repaired. Also after done cleaning such boards it helps to spray them with glyptal lacquer, and use the clear stuff on circuit boards. That is because it helps make them like new after they have been damaged and this is the only way those boards are easily repaired when a new one is not a possibility.
We call it Pertinax
Thanks for the comments...I actually have a bunch of phenolic sheets lying around, just wasn't sure what to call them. Thanks.
You don't only know your shit about amps you can play also, very smooth playing
Thanks, Rich.
one would hope those talking on youtube would have experience.
Why would someone talking about electronics repair need experience as a musician? Are you good at repairing amps? Maybe you shouldn't be playing guitar, then. Your logic.
Yeah, man, the way he hit those 5th and 7th frets on every string was badass...
better than most instructional "how to" videos I've seen in a long time...props on your playing as well.
some of us non-book learnin types really pick up quite a bit more info that is usefull by watching a master at his craft rather than sitting in a class listening to some necktie ramble on for hours. very informative and has qued my curiosity wich will promt me to definately watch alot more of your vids..thanks!
Wow, great details in this break down, and repair. I'm sure that was one more happy customer!, and we happy viewers, thank you for the slow rig down with so much details. I learned a lot. And the dive bomb w/o whammy bar was hilarious :D
No L! And you'll never hear me correct about pronouncing again. Because I'm a working man from AL. Dang!! I love your work. The way you talk us through, while showing hands on, is great for me! Thank you brother.
@5:00, that fiberglass material is called Micarta, it is an aviation grade insulator.
Man.... I LOVE those Migs. That amp + anything Mahogany with a P90 in it = Rock and Roll! Great video!
I had an LP Jr. just off camera. Mahogany and P90. Guess I shoulda grabbed it.
Yeah I love that Jr of yours....
Yeah, now go to gulag
It did sound good after the repair I'm impressed
@@beelbug2396 got a link?
I always establish negative bias supply first.. without it, obviously the power tubes will turn on hard and red plate... Been building hi fidelity tube gear since before you were born, so this is voice of experience. I must say though that you have learned the craft of musical instrument amps damn well and find your vids refreshingly competent, with a nice bit of music tossed in for great fun.
What was the final plate voltage with the -77 grid vdc? The Sovtek 5881's are a 6L6GC internally, they can handle a few more than 19 watts PD. Those Mig 50's are pretty awesome amps. They basically slammed a 2204 and 5F6-A(with circuit revisions even) together, jacked up the juice and sold it for a price anyone could afford. (Wait a minute.....they just modded a 5F6A in reality🎸🤘)
Regarding the transformers, I think the manufacturer only had tooling for one style bell for multiple transformers and filled the ends with material that's easy to cut/shape. Remember, we're talking about Russia here. The home of the stamped sheet metal assault rifles and hard liquor made from potatoes. Their shit just works.
Another great video! Thanks!
Plate voltage was about 525V. I didn't want to push the 5881 too hard. At this bias, they should last a long, long time in this amp. And it's still loud as piss.
...and you're right about Russian engineering. Their military spec hardware is usually excellent. If it ain't broke, don't fix it. That was their motto. Well, that and "death to capitalist pig dogs". :P
Yes, what they built out of metal usually was rock solid.
My dad always tells this joke about Russian engineering:
Do you know how Russians build a railroad engine? They take a huge block of metal and just cut away everything that doesn't belong there.
Their shuttle still exists but its rather dusty lol :)
I'm thinking the manufacturer didn't have the equipment to stamp out the cupped metal ends we're used to. Or perhaps that equipment had higher priority jobs. The ends shown there just need one of those metal benders.
I've been a sub for a while I'm just mainly a diy guy. I don't know if you've done like lesson style videos before to teach people like basics for amp repair but I think that would be really awesome I for one would love to learn more. Anyway thanks for the vids keep em comin!
Thanks for the encouragement. I could not do a better job than Uncle Doug. I encourage you to sub his channel for more basic instruction.
th-cam.com/users/Stratosaurus1
thanks i havent heard of his channel but i will check it out thanks again
Thanks to TH-cam, I now have an Uncle Doug, an Uncle Ben and a Guitologist. Thanks for the videos! I'm learning a lot.
You do a very good job with this channel. You explain what your are doing and why you are doing it very well, plus you demonstrate the results very well too. I used to be an Electronic Technician in the Navy over 20 years ago and I haven't been involved in electronics in a very long time, but watching your channel has given me the bug to start getting back into it. I play guitar as well, so I might get into amp building. Unfortunately my electronics skills are very rusty, but you have given me the itch to dust them off. Thanks for what you do.
I LOVE comments like this! I do hope you get back into the swing of things and remain interested. Go on Craiglist and find yourself a fixer-upper amp and dig in! A lot of times you can also find stuff in the CL free section for repair. Pick up an old console tube stereo amp or old organ and get your tinker on that way too. When you get up and going, make a TH-cam video and link back here so we can see your progress.
With the nation on lockdown its been such a pleasure watching your vids - one after another! Your content is highly addictive making me fear the impending doom of withdrawal once the pandemic is over. I'd dumpster dive with you any day brother!
I had a 92 Mig 60 and it was a great sounding amp.
Great video again Brad.
Hahaha what an ending, that harmonic drop was gorgeous. Fine work on the amp as well, thanks for sharing.
Whats your background as a guitar player?Something about those three note fast runs that I can't place the origin
I’ve just got my own mig 50, I’ll take into consideration all theses suggestions. Thanks for uploading very very useful !
Back in the 90's, I always wanted to get one of these. I came so close to getting one, but never ended up pulling the trigger. Despite their fairly poor construction, the circuits are pretty cool and placed in a nice package. it's cool that the Tube Midget was so ahead of it's time, and paved the way for all the little lunch box amps we know today.
Should it be pronounced "Soviet technology or Sovtek in short"
Excellent troubleshoot , refurb & maintenance work!
Thanks, John.
I am a simple man.
I see a Sovtek, I click on it.
me to
Awsome vids,Great info,loved your intro joke,I swear I voted :O on one of those. Have you done in the past or maybe might see in the future a Soldano head? peace.
Never so much as cracked open a Soldano. I've played through one or two before. Maybe one day we'll get to check one out here.
Nice fix Brad!
In Russia, the knobs go to 13 (according to the front panel)!
Regarding the transformers, maybe 'folded' sheet metal was a more cost effective solution, than 'stamped' bell covers.
As a sidebar, in 1975, I worked for the Canadian distributor of Hiwatt, where CSA required us to rivet metal shrouds onto the Partridge transformers to suit their regulations!
i was always curious about these amps in the '90s but never heard or played thru one.
This repair turned out great.
sounds good.... The material you pointed out inside the open transformer ends is a phenolic insulator. They use the same material in High Voltage 3 phase switch gear breakers between the phases.
Very good video. Question concerning tubes and red plating: If your tube is red plating does it always mean there is a fault or could it be just a bad tube? What would it cost to ship a amplifier head to you from Oklahoma? thanks in advance?
Yes, it could be a tube. If it was just one tube, I would have suspected a tube first, but this was both, so I knew it was in the bias circuit. Cost to ship a head...probably around $35-$40. Right now I'm taking a hiatus from outside repairs though. Hit me up around July, I should start taking things in again around that time: bradlinzy at gmail
I love you you drop all this knowledge on tube amps and then play your ass off at the end
bears on unicycles sure make some weird transformers
heheh. Trained by a guy named Stromboli.
Very cool!
What is the type diode you you installed?
Just curious; looks like old stock? Russian made?
It's a silicon diode. It was an NOS one I got in some large parts haul a while back. Not sure on the model number. I just checked the voltage rating and knew it would work.
Putin knows tone .
Trapper John - That should be on a T-shirt.
I'd buy one.
His sidekick Medvedjev is a huge Deep Purple fan, apparently. Wha the Man himself listens to (if indeed he listens to anything at all...), I haven't got the slightest idea.
hey the Putintone amp , you turn it on but the only sounds you hear are screams
putin ? he loves the sounds of bones cracking , gunshots , blood splattering on the wall , screams of pain , the usual commie psycho stuff
I just love your channel..i hope to have a youtube chanell one day..very informative, fun, instructional vdeos. Thank you Brad the guitlogist.
Thanks for watching!
You're a genius man! I've been wanting to get one for a while and you have a perfect video here taking a look at it lol!
Great work Brad! Love your playing too...
Thanks, Dan, as always. Good to hear from you.
I have just recently discovered your channel, beginning with the Marshall head found in the trash! I enjoy your repair videos- well done! When you change components out, like pots, caps, etc- do you rewrite the schematic to reflect any value changes?
Cool videos, mate. You don't have any plans to look through a (Sundholm bros. era) Sunn Model-T, do you? Or maybe, a Reval Model-T even? They're made out of Estonia and as far as I can gather, other than how it looks, they're faithful to the original. Cheers, all the best. :)
No plans, but sounds like something I'd love to get my hands on and check out.
This amp is one with The Schwartz and so are you my friend ... great playing , tone and overall vid \m/
People like you give me hope for the future of guitars.
at 4:50, that material is Formica.
it might be Micarta, also
I really like the tone you got from that guitar/amp/speaker cab combination t ! I'm from Czech Republic and I grew up around these Jolana guitars, since they were the cheapest solidbodies for begginers to get when I started to play guitar (late 90s). I never liked them at the time, but they kinda grew on me. Do you have any mods / tips for this model? I only remember appaling vibrato/bridge system, frets that didn't last even looking at them and horrible open back tuners
So many possible jokes,, so little time. Nice fix Brad.
You're an international man, and a busy one, Carl. I can appreciate your brevity.
I had one of these many years ago, The channel one volume actually impacts channel two as well, if you crank both up it screams.
AHHHHHHH!!!!
I still got a Sovtek MIG 100h. I had some minor issues with it over the years but for the price, it was well worth it. The 1/4" in/out jacks are crap and my bass pot did very little from new. Also had a noise issue that was related to the fact that it was "mishandled" during original transport, that caused the same one 5881 and fuses to blow. The amp tech pointed out the minor damage and was easily fixed. Currently going strong but Its had a bad high input jack for many years that I need to get around fixing. I just don't play it anymore. Good to see that other Sovteks are still kickin'.
I've had my mig50 since 95, and I have not needed to replace anything til just this year. Still love this thing as It takes pedals amazingly.
Can’t even imagine what kind of list I’d show up on trying to get parts for this thing.
A friend of mine used one of these amps in his stoner rock/post hardcore band and it really nailed that tone extremely well.
I read somewhere that metal plates around the transformers act like a shield to reduce hum.
Those boards on the XFMRs are made of Micarta. I used to have a Skateboard made of this.
The fiberglass plates in the transformer you mentioned, are phenolic plates for heat dissipation.
Another great video, my question is regarding that whitish substance you are using between the caps you raplaced, what is that and can silicone be used as well?
Fiber glass board is called phenolic,non-conductive etc. Was used by hot rodders back in the day to make carb spacers. Also used in tool and die work at times.
Great video series BTW, i am learning a lot. QQ, for those large capacitors you replaced, did you just cut the old ones out and solder the ends to the old posts or did you completely remove them from the old board? I am currently trying to fix my fender red knob amp and would like learn some best practices... thanks..
You make really good videos, your well spoken, very knowledgeable and an all around cool guy! Any haters can bite it.
I recall these being highly rated 15 or 20 years ago. Are they still around?
I think it's Mica that Sovtek used in their transformers for it's insulating properties. That would be my guess as to what those panels are on the power transformer. See watching them from 5 years ago, every upload watched i have gained some knowledge that i have been able to take away with me. Thanks Brad.
nice work,, its a few years ago i see that , but still good entertaining
material, its got to be the most satisfying thing to trace and fix an
awesome vintage piece of kit like that then put it through hoops
,sounded damn cool,!
The material on that transformer for caps is either micarta or glastic common electrical insulator from back in the day
Good video! By the way how does charvel xl 750 compares sound wise to les paul? Is it somehow similar? How do you like that guitar is it as good as people are saying. I have a chance to buy one. Thanks
Those boards on the ends of the transformers were made of a type of bakelite. Iworked in the transformer business in the U.K, around 35 years ago and we used it a lot.
Where did you find that second schematic with all the part numbers included? I've been looking for that forever and all I can ever find is more links to the same original one by Bruce Collins.
Nice Jolana, I have one myself, different model same tremolo unit.
I was wondering about the preamp tubes in this - are they really 12AX7 or 6N2P?
As always Brad, Awesome work!!! Thank you so much for your guidance!! You ROCK BRO!!!!!! \m/
I've taken apart a couple of HP tube instruments which had coaxial electrolytics with safety sleeves over them for the same reason.
We used to have a Sovtek mig100, it was a beast and never had any issues even after years of gigging still running strong!
P.S. Love the dumpster vids!
excellent repair and likewise on the shreddin' - Keep safe and keep them videos commin'
That amp sounds incredible! I´m always amazed at your skills man! i dont know 1/10 of the things you are mentioning but I keep watching (maybe ill learn by watching you haha)
Wow you were not kidding about using only 5881's in that amp. Hot damn
Cool vid again. Love your playing. The fault was a bad connection on the bias diode. When it made contact you got the correct negative bias so the anode currents were correct. When it lost contact then the bias would be 0V dc causing huge anode currents which in turn caused the B+ to drop. Must be a pretty good power transformer because a lesser one would have dropped its voltage much quicker! This amp is a good example of why there should always be a correctly rated slow-blow fuse in the B+, for this amp T500mA.
that was a pretty good accent!
How do you know which is the REAL accent? Maybe I am Russian spy!
that too, is distinctly within the realm of possibility - your southern drawl, withstanding. :)
Except for the hard 'v' he did when saying "video".
Pretty sure it'd be "wideo" with a russian accent.
And be sure to add a hard V to a the w's. Great wideo, you're velcome.
Nah, видео (their word for video)
Sounds nearly the exact same as English, but with the и sound (Vee-Dee-oah)
That thing sounds pretty good
i have a sovtek mig 100 and its a beast
Really enjoying your videos man. Love the whole trouble shooting journey. Keep 'em coming !
Great video Brad, as usual. However, I hope you checked the fuse. I had an old amp that i bought a while back, recently checked it because you say it so much and low and behold, not the right amp value...LOL. Thanks man! Bart
Hey thanks for mentioning Australia, we will not send out the killer kangaroo riding redback spiders :-P also love your channel mate!
Совтек, ffs
Cyka blyat..
Ну охуеть теперь. Пиздец.
I remember an old guitar player mag that talked about these before they were shipped and the article said it was being started by Mike Matthews, who started electro-harmonix.
I’ve been trying to find a demo of this into a new Marshall MX412 240watt. I might just get the new Electro-Harmonix MIG50 “reissue”...
Thoughts?
I’m new to amp and I don’t know much. I don’t want a straight dirty amp rig since I sometimes play some ambient post-rock stuff and some looping with fuzz. A lot of 70s style spacey prog-rock stuff.
I’m playing through an old Peavey 212 Classic that needs some new pots.
I have a Mig100 Sovtek made in Petersberg Russia. I've played it for years gigging in the US. Replaced the original tubes w/ Chinese "Sovtek" tubes purchased in the US. Never had any problems, used also in the studio for recording. This amp is a monster for those who are able to play, it delivers powerful tone and is loud. You must be able to properly set your system, just like any good 100W head, like a Marshall, etc. I love my Mig100 with the original 4x12 cab, I've had this as my main rig since 1998. Sovtek rocks!
SOVTEK amps are the shit! I've owned three and still have two. they're loud af regardless of their wattage rating. Nice repair vid dude.
wow thats amazing tone! is that the amp or your magic?
Amazing videos, been telling my buds.. Do you accept questions about amp problems? Thanks a lot for what your doin
You really balanced and blueprinted (and then some) that Sovtek...
Into another clean streetrod ala the Guitologist
When you first changed schematics I saw v1 said 12ax7 but your first schematic said 12ay7. You caught it elsewhere though, those are interchangeable though right( not identical though)? The 12ay7 being less gainy/ less output?
29:30 sound demo
Guitologist, do the Sovtek tubes use the same numbering system as American tubes would use?
Good enough for Sputnik, good enough for Sovtek. Yuri Gagarin approved
And Laika the Dog too!
Let's hear some more fat chords from you, through that Stovetek amp. Stove, because it sounds hot! She really sounds much better than the typically fizzy timbre I'm acquainted with from those things. Did you voice it at all?
Still have my MiG 50 . Great amp for the money I paid. Have had for 20 plus years
I bought a Mig 60 new and and Mig 50 at a pawn shop back in the 1990's. They didn't do much for me, but I've learned a lot about tube amps since then. They were a good cheap basic no frills amp. They were in serious need of upgrades as this video points out.
Our "amperage" started to go up. When we talk about amounts of electricity instead of saying "amperage" the correct term for this is "current". Pardon me for making this comment but I think that a good technic like you are should refer to things by their right terms. Best regards and by the way I like the way you work and solutions you have for some problems. Thank you for making your good work public by taking the time to record and edit all this videos. By the way you also play very well.
Old video so I don’t know if you’ll ever see this comment...but anyway, The input power voltage that is switchable from 110 American to 220 European, can a switch like that be installed on most amps? The reason I ask is I have two Redbear MK60’s that are 220V for the European market. I purchased a step up/step down transformer off of eBay to bump the 110volts from my wall outlet to 220volts to power them, but I can only do one at a time plus it’s a pretty clumsy set up and a pain to move around that way. It’d be nice to just be able to switch them to 110V and plug them in.
I really like what you did on this repair! You are really inspiring me to try and build my first amp. I’m a Network Tech building servers, fixing PCs and configuring routers and such. Never really did any electronic stuff. But Mojotone has a few amp kits I’m looking at for my first build. Do you think someone with my background can pull off building a guitar amp from a kit as a first build. I’m looking at the MOJOTONE STUDIO ONE 1 WATT 2-CHANNEL AMPLIFIER KIT. I need a practice amp with low watts so, I thought this amp would be a great kit to start with. What do you think? I would really appreciate your advice...
I've been gigging with one of these for years. It's an absolute beast!
if it's spelled "Sovtek", why would you pronounce it "both ways"? that makes no effin sense? :P just kidding, awesome videos! i play guitar myself, and love my tube amps, and while i am very technical myself, i would never go upon trying to fix them myself.. i'm glad there are people like you, and even better that you're taking the effort for us to being able to watch you fix this kind of stuff on youtube! thanks!
In Australia the main voltage is nominally 240v but it's often higher than that.
Amps with transformers that only handle 220v run hot and break down more often.
Combined with the hot weather here the extra heat from running 250v through amps made to handle 220v is often fatal.
This is a very good sounding amp. (Played like a pro as well.) I'm impressed. Interesting video all around.
Thanks for watching!
Maybe next time you could play a little Scorpions Wind of Change, for the Ruski theme. Nice job figuring out that bad diode push pole board bending business.
Good call on Scorpions.
Or, " Midnight in Moscow,"