Restoration class H professional power amplifier // Restore huge sound amplifier

[@cleodomarcms]

só um profissional capacitado para realizar esse tipo de serviço. Parabéns!!!

[@johnnyq1233]

In my youth, working at the Audio Room in Peterborough, Ontario, I've rebuilt a lot of power amps and several receivers and not once have I discarded only one power supply capacitor. They all go and any other cap that has a bulge for starters. I was actually surprised that there were no burnt up traces with an amp of that stature. I've done several Brystons, a few Haflers, a Phase Linear D-400 and, my favorite one of all, a Dynaco 410 that pooped its pants BIG TIME!!!! Took several weeks getting parts and fixing her up, but when it was done I took her home to my room and gave her the beans!! Ted Nugent and Cat Scratch Fever was all it took to blow the baskets out of my EPS-100s and it didn't even break a sweat..lol Baskets were replaced under warranty and that amp went on to party hardy for many years. It actually warped my stand because it was so heavy.

[@whynot6795]

You wold be more surprised if you will look at this video backwards (from working amp to trash)

[@sidereziztor]

@@whynot6795 i dont get it

[@hubbsllc]

I just picked up a Hafler P125. I have a more powerful but much lighter Crown XLS1000 but I wanted to have a second 2U amp on hand and these were being sold for cheap - by how they were labeled, it looked like they came out of an office building's ceiling speaker system.

[@robertgregory6678]

I was employed as a commercial audio technician for several years. There are many repair/restoration methods that I would love to help this guy with. Nevertheless, I give my admiration for his effort and willingness to expose himself to the scrutiny of the world of repair technicians. The honest truth: we can ALL learn something from every technician out there! 😊 Keep the comments coming. 👍

[@Rangerthelonewolf]

At the end of the repair if it works/functions as designed. Doesn’t it really matter whose knowledge of repair is better…(?)

[@rillloudmother]

@@Rangerthelonewolf isn't efficiency always a consideration?

[@Rangerthelonewolf]

@@rillloudmother sure. Most for companies. Time is money. But as a hobby. Meh a person can do/learn at their own pace.

[@whynot6795]

@@Rangerthelonewolf At the end is working amp because it's running before ruining.

[@treimers95]

​@@Rangerthelonewolfhe doesn't know if it works as design because he hasn't put a scope and audio Spectrum analyzer and Signal generator on it. He's half done. Good start, but not back to spec

[@johnwest7993]

I'm glad I no longer need to do commercial repair work. I like to take my time and make everything pretty instead of hustling to get the maximum amount of work turned out in a day. Now I just build or repair for myself. So I take my time, thoroughly clean everything, bend all the leads perfectly, and solder everything so it's not just functional, but pretty. Everything looks and sounds the same on the outside, but everything looks really nice, better than new on the inside, and I know it. The electrons don't care, but I do.

[@nevijakuftic8349]

Same man 😅

[@chinmeysway]

that is wonderful. i really am staring to appreciate this skill.... wishing i had it, but not sure where i would start. :) all the old things are made so well too!

[@krzysztofsz9076]

Dzień dobry! Też lubię naprawiać stare audio i poprawiać wygląd wnętrza. Układać równo przewody i poprawiać fabryczne lutowanie. Koledzy mówią że sprzęt ma działać a nie wyglądać, ale to taka moja terapia. Z Bogiem!

[@paulmichaelfreedman8334]

@@chinmeysway Just go to a garage sale, or a junk market and pick up any old equipment that you like and take it apart, and learn. Or maybe you already have some defunct device stored somewhere in the basement and forgotten.

[@DuffyF56]

Actually the electrons DO care. It is called high reliability soldering instead of what I just watched.

[@turboslag]

His dexterity manouvering that honking great soldering gun into tight spaces without melting everything in sight was impressive!! He's obviously done many of these rebuilds so knows what typically fails and measurements to expect. That allows rapid progress without going down false rabbit holes.

[@Kinann]

He was thorough to check for tin whiskers and foil shorts.

[@PlumGurly]

I built a Heathkit AM radio using a Weller soldering iron. I didn't damage too many traces with it. So if something bulky like that is all you have, you learn how to control it.

[@mooserov]

awesome work! my unsolicited advice for future work is never trust an electrolytic capacitor (big black cans) they are known for failing in huge batches and can expire on the shelf. If you change out one, change -em all!

[@hubbsllc]

I just feel like if you’ve removed them, it’s silly to put them back in if they’re more than 10-15 years old.

[@azar3006]

Agreed 100%.

[@PlumGurly]

I say the same for the MOVs. He changed the exploded ones. The other 2 should have been regarded as suspect. You don't know what mild over-voltage situations may have happened for years. So they might not withstand a larger spike.

[@marc49lewis]

I worked at the Peavey Service Center in the Crest Audio division for a number of years in the mid 2000's. The capacitors in the entire CA series were a bloody nightmare, oftimes exploding and literally destroying the transformer and damaging the rest of the amp as well. This fellow was super lucky in that the amp wasn't destroyed. These always would have ALL the caps swapped out as a precaution. The same sort of rubbish would happen on some of the even larger amps, creating absolute havoc. Even back then, those repairs were very costly.

[@freezemayer776]

Самое главное стрелочный тестер купить. И любые ремонты по плечу :)

[@brentcmark]

Those old crest amps sound amazing nice job resurrecting it.

[@vinibhz3100]

Parabéns! Que restauração top! Dá gosto de ver! Excelente AMP.

[@vkka4itor16]

jgf-у-меня-инфа как-открыть-порталчик-портал-с-помощью-сабов-наибольшее-нз-нз-нз-нз-нз-нз-🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗-jwjfj

[@adamcrux6829]

Man I would love to get my hands on a commercial amp like this. My neighborhood would never be the same again. Not to mention I would finally be able to flex these stage speakers I picked up years ago.

[@Crain-l9c]

HI 👋🤠 guys; I have repaired electonic equipment since 1970, And Trust me, The Crest amp WILL give you about 1000

[@izzzzzz6]

what? 1000 points out of 1000?

[@Crain-l9c]

Hi👋🤠; I wanted to convey "the Crest Amplifier" Will give about 1000 Watts RMS😉👍

[@Crain-l9c]

Hi👋🤠(Again) ; That model IS ALSO Stable to at Least 4 OHMS Impedance

[@carlosalbertoosilva8012]

Maravilhoso trabalho do começo ao fim!!!!!!!!!!

[@stas__ananas]

ржавые болты говорят про уровень ремонта. эти платы и так не особо крепкие а бу ключи с разных партий и заводов вовсе перечеркивают все вложения. емкость конденсаторов определили по заряду стрелки ну что тут добавить...

[@videorage]

Great amps for running PA subwoofers.

[@igorbarchan1302]

Глобально и очень обстоятельно!!! Респект!!!

[@recepatasoy9588]

bütün parçalarını nerdeyse değiştirdin ya helal olsun tebrik ederim

[@franciscorafael7975]

EXCELENTE TRABAJO, muchas felicidades. Gracias por compartir tu experiencia. 👍👍👍👍👍👍👍👍❤❤❤❤❤❤❤❤❤❤

[@АлексСкляр-й2з]

Парень, да ты весь усилитель по новой собрал! Молодец!

[@Pitchplus8]

This routine he has is just incredible. I bet he could even fix that amp blindfolded.

[@sonthanh686]

Bạn này ở VN, thấy sài keo 502 với ổ căm LIOA, bạn làm rất chuyên nghiệp ngưỡng mộ bạn

[@bonifacioandreandre3003]

Tenho uma unidade CA 18 o outro canal qd aumenta mt som ele vai no protec oq posso fazer?

[@mdtorikul7976]

🇧🇩🇧🇩 Very nice 👍👍

[@jeffreydookwah7056]

Currently own a Crest 90001. Wish l could have it restored like this. Jolly good job lad👍👍

[@whynot6795]

You really want ruin our own amp? 😲

[@ppdan]

As long as it works there is no need. Those are actually VERY reliable amps.

[@ovalwingnut]

That is the 2nd largest Toroidal Transformer that I have ever seen. I haven't been this impressed since I stepped out of the shower dripping wet Thank you for the video.

[@thurstonnguyen8500]

Great video- CREST product just don't failed from American Made. But for China Made- CREST, they're out of business. The late 1980, CREST- C20 was American Made. They never fail. They cost- arm and leg to owning sets. Daddy Junky Music was the place in late 1980 for local purchased CREST Products. But later year, CREST made in China, not durable, not lasting- disappointed. That was why they out of business- perhaps Peavey Electronics bought CREST in the late 1999. American companies- many of them Made Series Mistake with advance technologies shipped overseas for low cost productions and higher profits, but that destroyed Quality and Reliability.

[@mohammedisaa9952]

"low cost productions and higher profits, but that destroyed Quality and Reliability."..... Isnt that the case nowadays.... everything turned into shit post 2010.... Profits are worth more than reliability and quality.... time is money, so quicker in, quicker out, just bodge the repairs or build, ...... sad way of thinking, also, repair shops that "swap" good parts for broken/faulty parts, so you keep coming back and paying them..... Thats why i learned to do my own repairs..... now i just repair for friends and family, give them a good deal, and most of all..... I AM HONEST..... 🙂❤️✔️

[@marc49lewis]

Man - you sure got that straight. As I mentioned in one of my other comments here, I worked at Peavey in the Crest Audio service department. When the chinese junks started coming in, many of them would literally explode as soon as they were plugged in and turned on. Rubbish.

[@alexs6520]

- "Какие замеры ты делаешь ?" - "Да от балды тестером везде тыкаю в разных режимах .. Зачем мне замеры ..."

[@RigasRadioRupnica]

Слушай, а зачем и чем он платы чистит ?

[@ПавелТкачев-щ7ф]

@@RigasRadioRupnica вэдэшкой, лол

[@olehadro]

​@@RigasRadioRupnicaБензин

[@sergeyosinphotography6862]

русские и тут успели......

[@focka73]

Laber net

[@klauslaus2535]

With the simplest means we repaired a functional device again, all respect for this good work. When I consider the effort that goes into repairing electronic devices here in the country, I'm surprised that you're successful with this complex repair with this amplifier.

[@leosmith848]

I used to work in a company that made stuff like this. The repair departments was simply full of girls who unsoldered every power semiconductor device and any others that looked burnt, and replaced everything. The transistors all went to a transistor tester and any that worked went back into the replacement parts bins. About 5% of the boards still didn't work. A tech on 3 times the girls salary got those. Any boards that werent fixed in ten mnutes were stripped of anything expensive and tossed.

[@ПавелТкачев-щ7ф]

This video is completely fake. From the first to the last frame, with the exception of painting. There is a whole class of fake videos about “restoration” on KZbin, and this shit is persistently pushed onto my home page...

[@ПавелТкачев-щ7ф]

***This video is completely fake. From the first to the last frame, with the exception of painting. There is a whole class of fake videos about “restoration” on KZbin, and this shit is persistently pushed onto my home page...

[@ПавелТкачев-щ7ф]

Of course, this video is completely fake. From the first to the last frame, with the exception of painting. There is a whole class of fake videos about “restoration” on KZbin, and this shit is persistently pushed onto my home page...

[@leosmith848]

@@ПавелТкачев-щ7ф Looks pretty much like repairing any big old class B tranny amp that I have ever repaired. And that would be a lot

[@OtherMike5000]

THIS….. WAS…. *AWESOME!!!*

[@waynebradley2702]

only thing you missed was painting the outside screws, but still great job...inspired me to clean up some of my older equipment to bring them back to life....appreciate the video.

[@rohimasek6312]

Mantap oom

[@pawellok]

Is it a kapton tape between transistors and coolers? Washers should have very low thermal resistance, so kapton tape shouldn't be used here. Those old white/transparent washers were better than kapton. Even mica washers will be better.

[@chinmeysway]

one side seemed dead.... hmm maybe it was that one with the kapton

[@guillermobrandt291]

Espectacular reparación! Felicidades!

[@cecilclarke3308]

this kind of repair can be done with analogy and digital tester,but it all depends on what wrong with the amplifier

[@cecilclarke3308]

this kind of repair can be done with analogy and digital tester,but it all depends on what wrong with the amplifier

[@cecilclarke3308]

this kind of repair can be done with analogy and digital tester,but it all depends on what wrong with the amplifier

[@alessandrothando5396]

Show que perfeiçăo esse deu ttabalho mais uma maquina de guerra a vida ❤❤❤❤❤❤

[@94Fayin]

Congratulations .. very good , excelent you work ..

[@alexperm2049]

Усилитель был рабочий.

[@guzelsanart]

Transistörler eşleştirilmeden paralel takıldığında bir süre sonra Hfe değeri yüksek olan daha çok akım vermeye çalıştığı için bozuluyor. Buradaki tamir esnasında eşleştirilmiş çıkış transistörleri kullanıldı mı anlayamıyoruz. Ben kendi inşa ettiğim bir amplifikatördeki 4x4 mosfet çıkışları eşleştirmek için 40 adet IRFP240-9240 almak zorunda kalmıştım. Güzel video severek izledim. Teşekkürler

[@mrdali67]

Very nice work. God old reliable stuff, even nearly noone uses these old Power amps anymore. New Speakers usually come with build in Class D amps unless it's really big PA Systems, and much of it is junk unless you have the money for the good stuff. Can't imagine breaking my back on carrying Stuff like this around anymore🙃

[@juanernehygonzalezcastro8009]

exelente

[@BoudewijnvanHouten]

What a tiny transformer...;-)

[@user-Fredy295]

Mis respetos hermano por tu inteligencia y pasciencia! Dios te bendiga mucho te mando un abrazo desde Monterrey México departe de Fredy Amézquita!

[@wijayacanel4062]

Hadir nyimak salam santun power nya mantap 👍

[@rickydasic2740]

Saan po ang shop nyo ty

[@MarcoAurelio-xn3cx]

Boa noite a todos fi cou zerada parabéns muito proficional

[@JamesE707]

Kudos to all the engineers who designed this amplifier, this isn't lego!

[@alexandrsherbakov9878]

Не понимаю, что не понравилось хейтерам? Что не замерил емкость фильтрующих электролитов и не подобрал транзисторы по усилению? Не снял осцилограмму? А может ему это не нужно, все равно "маршала" из этого усилителя не сделаешь, а ролик был бы на десяток минут длиннее. Он сделал все по уму, правильная диагностика и лечение, все работает, его устраивает. От меня лайк.

[@youtubevideos4282]

aos 35:34 ...amigo você testou dois NTC diretamente na placa ,eles estão ligados em paralelo ?????? bom trabalho ,eu gostaria de ter seu tempo e sua paciência PARABENS !!!

[@cleitonfelipe2092]

Estão ligados em série

[@godsinbox]

In my country, before international freight was a viable thing, they made 'professional' audio amps locally. I remember hauling that massive lump to a gig and just the anticipation of just when it would drop its guts into the speaker bins. Sometimes it would be the gig straight after the last repair, sometimes it would wait until the pain of the last repair bill wore off. One gig we heard the huge zzzzzzzzpppt, and being at least 60 miles from home we had to find a local band generous enough to loan a PA. Ironically, our professionally 'designed' and 'built' solid state 'maintenance free' 1kw PA was replaced with a 60w all valve sports oval four column PA and it effing rocked harder.

[@willwill5595]

Looks like fun - wish there was explanation about why and what is going on

[@PlumGurly]

Yeah, same here, but I made sense of most of it. * He changed the resistors and diodes at the beginning after the low readings on the meter because they were bad. It looks like dodgy repairs were done in the past since there were resistors wired in tandem. That is what some techs do when the resistors they have on hand can only carry half the necessary current. You double the resistance value and wire 2 in parallel. He put the correct ones back in. The resistors were open or near-open. I didn't pay attention to the diode, but it was either open or shorted. * He cleaned under the capacitors because they can leak chemicals onto the board. That can be conductive and perhaps corrosive. * He only replaced the most obviously faulty of the capacitors. That was not the ideal way to test them, but this was more of a sanity test. Capacitors should read almost shorted and then become less conductive as they charge (yes, the meter charges them). 3 didn't do that right. The one that shed its label didn't deflect the needle. It may have lost its electrolyte, so it did nothing. There are no real ideal capacitor testers. Ones purpose-built for this use a formula that can be misleading. They test in relation to time. They can be leaky (electrically) and take longer to charge than normal, so a capacitor tester may claim they have a higher capacity than they do. It's like measuring how long to fill a bucket with holes in the bottom. You use more water but the bucket isn't holding it. Many would say you should just change them all to be sure. * He unsoldered one leg of each resistor connected to the transistors to prevent them from interfering with measuring the transistors. Many of those were bad too. * He bent the transistors and the first row of resistors to denote which ones were faulty. * Some of the SMD (surface-mount) parts were also faulty like diodes. * He replaced the 2 exploded MOVs. I would have changed them all since there is no way to know how good a MOV is once they've been used for some time.

[@carloscardenas2815]

You Sir are a magician. I admire your work. I'm also a repair technician and this is a hard repair. You got to have good knowledge and skills to do this. Keep the great work, Cheers!

[@delacruzclarissa540]

im watching and like ❤

[@warunakangara6791]

Great recovery ❤

[@dungnguyen-jj2uw]

Bạn làm rất gọn gàng và chính xác cao.

[@victorgutierrrez7787]

Muy buena la reparación quedo como nuevo mis respeto

[@lebaksarkumahpetualang5740]

Saya tertarik sama power power nya..

[@WalterLopez-cz7bk]

QUE MARAVILLA,¡ ES UNA DON¡¡¡¡

[@Daniel-vh9lg]

The good stuff, what you came for starts at 3:15 ☺

[@vanhocpham5245]

Thợ giỏi thế.👍

[@adailsilva4785]

muito bom vc é o cara deus abecoe .

[@АлександрДовгаль-у6р]

Ремонт дороже усилителя. Моё почтение.

[@luke144]

Class H. Nice. Rail tracking in big amps like this is a good idea.

[@JeanTshimona]

Waouh c'est ça j'aime ça

[@limbeauties5903]

If finish it will be unreliable in actual use.look at the solder,remember this a high power amplifier it operates at a high current high voltage even in just half power operation.

[@pitasim3285]

unprofessionally soldered

[@robertoteclasoficial2622]

GÊNIO DA ELETRONICA APLAUSOS DEUS TE ABENÇÕE

[@picobyte]

It certainly looks good.

[@peterdefrankrijker]

That paint job? One of the worst I’ve ever seen.

[@picobyte]

@@peterdefrankrijker #care

[@jufritomelo0210]

Nice broo...

[@arielalejandromelian489]

Muy bueno el tegnico la tiene bien clara a la electrónica si agun dia vienes a la argentina te juro q te voy a visitar ere lo máximo

[@mdshagormirza6698]

Vai tumer video onek Valo lagi

[@100ge]

赞，超级认真、超级有耐心……

[@haroldopaulino779]

Parabéns!

[@RahmawatiAR]

You are the best enginering

[@MarioCruz-ug1xt]

Te felicito por esa buena reparación, saludos cordiales, México.

[@newtechinvention105]

Amazing, so I proud of you.Thank you for your sharing

[@Warg666]

Biggest amp I ever got to mess with with a Hifonic's Colossus VII (Banned Edition) due to 2 Zues boards in it working as 1 amp, was asked to get one side working solo vs as the other side was shot to hell, and did!~

[@sonisaini-ls1qk]

Super 💯

[@Puf_Puf]

Уровень мастерства поражает

[@huytv2202]

Very good repair, you must have some ingenuity to fix it

[@valdivinofrazao8674]

Perfeito ótimo trabalho

[@lecesleces4633]

Us743❤

[@gersonmel]

Parabens, ficou ótimo.

[@rooholahabedinzadeh6233]

کارت خیلی زیبا و قشنگ بود خوشم اومد

[@CrustyRestorations]

Thats some knowledge 👍👍

[@ivonaldogomes4139]

a eletrõnica é muito top.... principalmente o trabalho de quem as pratica .... parabéns

[@Crain-l9c]

HI 👋🤠 ; I have noticed " Comments from almost EVERY COUNTRY in the WORLD 🌎🌍...It would be nice if the Host Server would provide" MULTILINGUAL " TRANSLATIONS. THAT way EVERYONE would understand the different"Ideas" and work TOGETHER 😎👍

[@vkka4itor16]

hf-у-меня-инфа как-открыть-порталчик-портал-с-помощью-сабов-наибольшее-нз-нз-нз-нз-нз-нз-🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗🤗-jwj

[@fredsantos9505]

belíssimo trabalho parabéns ❤❤❤

[@mdssolder]

good job 👍

[@gerardocazares9449]

Así quiero un técnico sercas de mi domicilio felicidades y de dónde es usted? Yo soy de Monterrey NL México . gracias por compartir

[@oqueedeuseoquechamadodeus5346]

bom trabalho

[@Ivanko77]

Awesome!!!

[@vinodgusain2609]

Great work sir.

[@KC-pf4tj]

Nice job

[@megamanguy]

Big badass amp Noice 👌

[@NilanthaBasnaayaka]

super

[@MazHziemOdesa]

Good job👍👍👍🇮🇩

[@Lintangbbt]

the audio is cool

[@kayros5723]

Excellent job!

[@andrzejnowicki1447]

💪👍👍👍👍super

[@Celar_Axel_TV]

Good good

[@李光-e5d]

喜欢你的视频

[@TheAndrew3777]

Super super super ❤❤❤❤❤

[@jubydulhaqmunna2715]

Great work bro

[@lmwlmw4468]

Great work.

[@jardesonrodrigues522]

Gosto muito desses conteúdos sou técnico

[@xocementart1818]

ok quá chuẩn

[@제이슨킴]

awesome!