New D-lab series Basic Training Tube amp repair How to really fix a dirty pot Not what you think

You asked, I deliver. Going back to basics, focus on the real cause of the tube amp fault. This new series will address many common malfunctions, help you to quickly resolve the issue, no BS, instant solutions. I have shown many full repairs in the past, many questions have surfaced, now I will address them and give you to easy resolve. I am doing my best to guide you thru the process. I dont want to leave this world without leaving this legacy! We will start with Class A circuits, then advance from there. Hey guys, D-lab is full time now, my mind is at 110%, and need to make this work. Otherwise I will be spinning a cardboard sign. Let me know what you want. Help support d-lab, see d-labelectronics.com

[@DavidBrown-ez5jc]

Absolutely a legend teacher to all us audio wannabe amp techs

[@joepulltab6355]

Awesome!! As someone new to electronics and building amplifiers, this series will be very helpful. Thanks Terry!

[@tomasjones3755]

Appreciate this series; looking forward, to more!

[@haroldsparkman6008]

Thanks Terry. Looking forward to learning from an excellent Technician!

[@jerryjohnson3801]

thank you, I've been looking for a truly beginners video series on how to troubleshoot power amplifiers

[@johnsalaman503]

I personally enjoy every one of d labs videos..great job terry

[@stevedanby8042]

Now this is a great idea and doing it in this manner will be invaluable to so many people who just want to learn and have an interest in this. Forums are great but seeing and watching makes all the difference. I'll be tuning in

[@d-labelectronics]

Thank you Steve, I am trying to up the game

[@simonspeaker]

yes!

[@zundfolge1432]

wow! MY LAPTOPS speakers wouldnt play the rumble but when I hooked up a mega boom to it, I heard the rumble.

[@chowmein6219]

Thanks Terry. Looking forward to more in this series.

[@josephmagedanz4070]

Looking forward to seeing this new series...I'm sure I will learn a lot. Thanks!

[@joeteejoetee]

I love the look of "Orange-Drop" Capacitors!

[@kmackiss]

Thank you Terry , for this new series of video's . The testing with is what I am always looking for . Please keep releasing your great video's .

[@iangray7410]

Any idea what wine he likes ?

[@zulumax1]

I think what you are doing is a great idea! Reminds me of what Marlin Perkins did with Mutual of Omaha's Wild Kingdom show back in the 60's through the 80's. There was a disclaimer at the beginning of the show that all events may be staged, but depict actual animal behavior in the wild. A great learning tool that recreates events which would be hard to come across by chance in the wild and catch on film.

[@schmaler68]

I think I should urgently replace my capacitors on the Orange OR120. That's probably where my problems are. Many thanks, and best regards from Germany, Kay

[@Germinalx]

Lots of guys on line. I like Terry.

[@skycarl]

What a great idea to put out there Terry. Gonna help a lot of people.

[@billhart4710]

Thanks! Well spoken, concise - just what I needed to know. 👍👍 ...

[@simonspeaker]

WOW! Could be awesome if you could start explain from the very basics and schematics 😮

[@Uuuuuuurrgggggghhhhh]

Very good, Terry. I like this new series!

[@MrAlFuture]

In really looking forward to this series. Great idea! Thanks, Terry!

[@jonathanhorne6503]

Topic suggestion. Troubleshoot a conductive board.

[@briancassidy6678]

Keep 'em coming! Great time and money saving tips are always appreciated.

[@LitesLAB]

Great video Terry, the troubleshooting was presented very well and easy to follow. You rock!

[@jackleg266]

terry, wonderful! anxiously awaiting next clip.... thanks

[@mrd5376]

Terry,Awesome video as always wish you were closer to my home town! Thanks Dan Penticton BC

[@zulumax1]

When I heard the sound I knew what it was, DC across the pot. Once you have heard that sound you know. Then you need to track down the source of the DC and how it is getting there. I had a stepped type treble and bass controls on a Magnavox console that would pop with every step change due to leaking caps. Replaced the coupling electrolytic caps in the preamp and amp and no more pops.

[@davehunt5706]

Fantastic news Terry You are the wizard

[@74cannelle]

Very good approach, Terry 👍

[@BCEpedals]

This is wonderful to know! This going to be a great series! Excited for more!

[@iangray7410]

I know he likes red wine, but which one ?

[@d-labelectronics]

Robert Mondavi Cab

[@stephenfabiszak6039]

I really enjoyed the video. When you verbally reference the schematic diagram, could you show us on the actual schematic if you have one on hand?

[@bobr8565]

Keep ‘em coming Terry!

[@jimhibert]

Nice video, Terry. Please keep ‘em coming.

[@cameronstolhand7149]

Great idea! I'm down to watch the entire series.

[@simonaguilera1688]

Enjoy it very much. More tutorials please. Best regards

[@John-te3zd]

Great video Terry, love the new series

[@denniscrofoot9238]

Great job Terry, I could even understand it.😁

[@patprop74]

Looking forward to all of this series! Excellent Terry

[@michaelgregg187]

Quite helpful, Terry! Keep em coming please

[@vitoleo7197]

very nice Terry. 73 from ON6VL in Belgium

[@markcunningham6086]

Yep....Im with ya Terry. More please.....

[@jdmccorful]

Good deal! Looking forward to this series. Thanks!

[@michaeltuckey7]

Great video! Looking forward to the next video in the series!

[@WillemvanLonden]

Keep 'm coming, Terry!

[@rickcarter6591]

Excellent Video. Short and to the point.

[@colinsvid]

Good video terry, I’m looking forward to seeing the next one

[@zbaby82]

Excellent! Please more videos like this.

[@ckdesign]

nice idea for the series Terry - thanks for all the great content. you mention the problem here being a leaky "tone cap" rather than identifying it as a leaky "coupling cap" feeding the tone stack. thought it might be helpful to point that out since "tone cap" is the standard term referring to a cap between a tone pot and ground responsible for altering tone and using that term to describe these frequency tuned DC-filtering couple caps could be a little confusing for some audience members. cheers.

[@freddycookjr.2164]

GREAT WORK THANK FOR ALL YOU DO / YOU ALREADY HAVE HELPED SO MUCH LOKKING FORWARD TO SERIES

[@CC-te5zf]

Howdy D-Lab! This was a great lesson!

[@PhoenixGuitars]

Thank you! Really looking forward to this insight and knowledge. Please continue!

[@jmormino5465]

Love this Format as a series. Thanks.

[@bugzeye]

I really like this idea, thanks for all your knowledge and problem solving videos.

[@user-ud2eh9ry4m]

just started fixing amps love this and i have seen the resistor thing years ago when i first got into tube amps as a young teen tried to help him but told him you have messed with this thing to much

[@bkbinj6320]

Thanks for sharing your knowledge Terry.

[@richardbrobeck2384]

Terry Nice video when I was in high school our Electronics teacher had us built this RCA AA5 chassis but he did not tell us he included either wrong value parts or defect parts !

[@umajunkcollector]

WTG Terry, thanks again for sharing your valuable knoeledge. Those dang leaky caps strikes again! Knowing which stage or section of the amplifier to troubleshoot comes from understsnding the circuits of each staage, power supply, preamp, amp, or speaker. The preamp cam be devided into sections, tone, fx, or controls and their tubes. I've learned from you a lot aboit tubes and their purposes or multipurposes, how to break down each stage by their tubes, PS, preamp, and PA. One thing that I do first is troubleshoot for bad connections, then old caps. Way back, we tested tubes first at the Rad Shak becsuse the caps and pots were not old yet. Then maybe a blown speaker from abuse? Sometimes we got lucky, and bought a ""Lifetime"" tube or cheapo speaker from Radidio Shak!

[@umajunkcollector]

PS: btw, way back, I had a Rad Shak MIJ guitar amplifier that had two twelves as I recall. It had four tubes, I guess, since it had reverb and tremolo. It was either a 6aq5oir 6bq5 amp. Lafayette sold a simular guitar amp that was supposedly a rebadged Univox. It serms that you favor "made in the usa" amps. The MIJ copy cat amps were built cheap, and at best were good for home practice. I'd like to see you do a vid about an old cheapo made in Japan copy cat amp, to see a diagnostic 50+ years later. . Rad Shak amps are quite rare, but you might find a tubie Univox for funage.

[@richard66754]

This is awesome! Thank you for sharing your knowledge with us!

[@gigitoby5359]

Greit Terry manny thanks to show how repair old amps Tube . very greit series I appreciate you and yours fantastic videos , bay from ITALY

[@kenwhelan3003]

A great new series... thumbs up here in WNY..

[@entangledwebmanagement5842]

Absolutely helpful. Thanks, Terry.

[@edwardmonsariste4050]

It’s always such a joy to work on old hand wired boards and chassis mounted sockets and pots. Today’s typical tube amps are ugly multiple double sided circuit boards with surface mount components and a rats nests of ribbon cables. You’ve got to have an electron tunneling microscope to see what you’re doing. You literally have to rebuild an amp just to change a blown hissing resistor. Good look on your new full time work. Always enjoy your videos!

[@openup007]

Two knobs up… Good job Terry!!!

[@larrpeninger]

I love this! This is information you don't ever get from a repair center.

[@vuch9208]

I really didn't hear the rumble before or after the changes. I did enjoy the video!

[@kimmassey6596]

Great job. Please keep ‘‘em coming

[@theoloutlaw]

I would not have thought .3 or .8 of a volt would cause that much of an issue on the other side of the Cap. Thanks Terry for the 'awakening' of such things.

[@werner.x]

Thank you. Great idea! And really needed. Please continue.

[@jeffberwick]

Very clear demonstration! Thanks

[@justgary4342]

Very helpful tip. Thanks Terry!

[@czgunner]

Awesome video. Looking forward to more!

[@jefflangton6033]

Thanks Terry Good Stuff...Jolten Jay Aka Jeff 👍

[@archiepaton9263]

Looking forward to this. Great idea.

[@chattanoogaguitarworksguit7956]

Great presentation. Well explained and clear tests/ results! Looking forward to the next episode. You could charge for this stuff

[@pauldow1648]

Short.sweet.and to the point. Helps me to learn how circuitry is supposed to work...

[@DiegoGonzalez-jo2tw]

Thank you for this knowledge Terry! We appreciate you!

[@ScottyBrockway]

There can be leakage on the board itself too, and changing the caps is just a temp fix and they aren't really leaky. Should desolder one end first and check if there is any voltage to confirm suspicions. If there is none, start measuring the board, they attract crap from smokers and moisture, also that wax that CBS started adding later can become conductive and it needs to be removed in some cases.

[@eugenepohjola258]

Howdy. Great. I had a persistent problem with my DIY amp. The driver stage of one channel sounded awful and the DC levels were nuts. I disconnected the input cap. No change in levels. Then disconnected the stage neg. feedback cap. Still no change. Finally I disconnected the global neg. feedback cap. Voila ! Unmounted the cap showed a resistance of about 800 ohm. Brand new cap and faulty ! After replacing and reconnecting everything the stage worked fine. Since then I have encountered another leaky cap in the bag of 50 items I bought. Lesson. Sacrifice the time to resistance check caps before soldering them in. Will save one a lot of headache in the long run. Regards.

[@SStudiopro]

Love this Terry. Looking forward to to get into tube amp repair as there ain’t many in my area. Thanks

[@MrSonicAlchemy]

Excellent video. Concise and informative. Thank you!

[@dhpbear2]

Congrats on the new series, Terry! xraytonyb is doing a similar series on his channel. Building an integrated stereo tube amp kit and walking though EVERY aspect of it. Tony even tossed the circus board in favor of point-to-point wiring! The circuit is SO simple, it's comical seeing it laid out on a PC board!

[@zulumax1]

David Perkins, I love Terry and Tony, both great teachers of how to do point to point wiring, and do it right. It is an art, and takes that old school knowledge which is becoming a lost art. I tip my hat to a couple of great teachers here on the tube.

[@OIE82]

Great idea Terry. I always look forward to your videos. I don't know if you would want to give away your parts supplier information, but if you do, showing where and how to find good parts would be a good video too. Of course, that may overload and deplete those vendors' supplies!

[@donaldfilbert4832]

Excellent series !! I was surprised that a small leakage DC voltage (under 1 volt) could cause that kind of problem !! Thanks for the series !!

[@edcataldo7019]

Thanks Terry for giving us access to the D-Lab Team!

[@jakeblues3676]

Terry you’re amazing and we so much appreciate the help given HAM Radio

[@kylecosentino2271]

Loved the format

[@christyler9026]

Great content!

[@dumpedcabledumpedcable116]

Great idea for a series!!!

[@ronmorey3475]

Excellent series! Thanks!

[@robertcox5228]

Hi Love all your videos. Maybe my hearing is not so good, but I could not hear the rumble. I think a seperate mic for the amps speaker would help. Dub in the audio track. Various sounds amps make when sick are important for diagnostics. Looking forward for more Dlab videos. Bob

[@asahemenway2926]

This is awesome! Thanks a lot Terry!!!

[@JuanMotta]

Thanks for the class!!!

[@blues61]

Love this new series. Please continue.

[@all_invite_0hm]

Great idea for a new series!

[@mchavez56]

great. short and sweet! good info.

[@fuzzprobe]

Great video, thanks D Lab!

[@tonymowbray3041]

Good Stuff Terry - love it

[@christophersambuco9414]

I'm always glad to see a new DLab video on my KZbin feed

[@analogblues9606]

I love it! Thanks Terry!

[@davemclaughlin2305]

Well done, keep up the good work!

[@danieljohnson6817]

Great video! Thanks and keep’s coming!