How to build a custom 3 watt 6F6 tube guitar practice amplifier from scratch by D-lab

[@NGH99999]

That overdriven tone is SWEET. What a gem of an amp.

[@patprop74]

I knew Terry wouldn't let me down, Just picked up a chassis for a Marconi that has a nice transformer and 6f6G the glass variety, and a 5y4... And now using this as a guild I will have a cool little amp! Thanks Terry As always, you are a Champ

[@audiotechlabs4650]

Great video Terry! No you cannot build this little amp for less than $200. That is truth in advertising. You are honest about it and you did the next best thing, you showed the schematic and explained how to source parts and showed what it looks like up close! Bravo! I only hope those who have been asking will appreciate this video as much as I do! There are no secrets to building your own tube amp. The internet will teach you. You do make it look simple, but that's because you have did it for years and have the knowledge and experience. Thankz

[@d-labelectronics]

Thank you my friend. I felt it was a good time to share building these little guys. Since I am not a millionaire, the best legacy I can leave is some fun and my love for this old stuff. TD

[@RobynTapps]

Uhhh I don't know what youre talking about... The radio he built this from is still only like $150 Canadian... You should absolutely be able to build this for under $200 USD

[@timmooney7528]

Nice Easter egg at the end regarding the Les Paul Jr and the Mountain T-shirt!

[@geemac7267]

Very generous of you to show us this Terry.

[@robertpuckett7412]

I'm a young tech at a music store. I have learned so much from you! Thank you for your work!

[@d-labelectronics]

Cool deal man, welcome to the art. I have been toying with tube stuff since the age of 12. Have you checked into Ham radio? That hobby is a great asset to living the tube life.

[@robertpuckett7412]

+D-lab Electronics I would like to! but I am also a musician, and my time for other hobbies is limited.

[@kengevers8738]

A great "Champ Amp" project for beginners in amp building. For you newbies, after you build the amp, try hooking the amp into different speaker configurations and have some fun. You will be surprised how that thing will sound into a 4x12 cabinet.

[@chrisbarrett5132]

Hi Terry. Just finished one of the here in the UK. Used what I have, a 190-0-190, diode rectification, and a 5K OP tranny. It just sounds so sweet, thanks for publishing the design. The chassis looks so empty with so few components!

[@d-labelectronics]

Excellent, glad it turned out well my friend

[@williamjenkins9423]

Chris barrett - I'm going to build this amp. Did you use the hammond 369EX power transformer?

[@williamjenkins9423]

Would I be better off using a 5k or 8k on the op xmfr?

[@ralphyrocket5770]

Alcohol and electronics!!! Its my favorite hobby!! I just LOVE it..glad I'm not alone! thank you sir!!!

[@fve1352]

why does this guy not have 17m subscribers instead of only 17k... he is a genius!

[@curtiseverett1671]

he is that great sense of humor too!

[@leewarren]

Nice one, Terry. Thanks for sharing tips and secrets!

[@jjn11235]

I built one of these using the PT and 6X4 from an MR-10 per your suggestion. It was easy and inexpensive, and it sounds great through a 12" Fender speaker. I especially like the transition to breakup; I think the pentode preamp is responsible for that. And it's dead quiet: no hum or anything like that. Thank you for sharing a fun project.

[@mike60510]

I see that the D-Labs amp uses a 6x5 rectifier. As you mentioned, a 6x4 rectifier is used in the Regency radio. Did you just substitute the 6x4 for the 6x5 and use the same schematic? Is there an advantage to using the 6x5?

[@activeeq]

A big thank you! Yes, budget is big concern for me and your willingness to share your knowledge is appreciated. I have a table of projects waiting for me to buy a decent soldering station and variac. Everything from a tube office intercom, BH 187 film projector and institutional record players from audiotronics and mewcomb. All of that stuff would be sitting indefinitely without your videos demonstrating the "can do."

[@mosneedly3751]

Thanks man, this one sounds good. I bought a stromberg carlson at an estate sale with these weird old mid 30's 75, 42 tubes in it and wound up here. Appreciate your work.

[@skycarl]

Thank you Terry. That was really nice of you to give us that info. Take care bro.

[@JesusIsLordofMybeing]

Awesome video Terry!!! As usual an A+++ master at his art....Oh and FYI, you can't ever please everyone so don't waste your time trying!!!! You're the man Terry!! tnx

[@d-labelectronics]

Thanks man, Yes at times some of the remarks are a bit unpleasant, however the good highly outweigh the bad.

[@startend7196]

The little amp head sounds great!

[@6A8G]

Please check the pin numbering on the 6SJ7 - I think the supressor & screen grid pins are ass-about-face. Thank you, signed Mr. Smartass.

[@williamjenkins9423]

Pins 3 and 6

[@briand9513]

Great videos.. I just got into tube audio amps so these vids are priceless.Just rebuilt my first amp, a SE maggie with 6bq5's.. And, to reference a previous comment, I'm a ham radio enthusiast (W3ATT.) Thanks again man!

[@d-labelectronics]

Good to meet you Brian. Do you operate CW by chance?

[@briand9513]

Yep! Lots of cw - my favorite mode!

[@egotripband]

really cool sounding little amp . thanks for posting .

[@mendamp1715]

Thanks for the informative video, I'll try building the amp. Seems like the tube complement of an old signal tracer, like the old EICO 147, would work the same way, that might make a nice video for you to make! Use the same chassis and re-spin a cheap signal tracer into an Champ Amp...

[@rciancia]

Well done Terry ! It also be really easy to throw in a basic tone control in there which is what I do when I make these little amp. Excellent job, thank you. Ron

[@d-labelectronics]

Cool deal man. The 6SJ7 is a great tube for these small amps.

[@kxmrock]

intro, that sounded so good... real nice

[@silvermica]

You are a gentleman and a scholar.

[@TheRadioShop]

Great tutorial Terry. So many folks ask me how to do this. I will send them to this video. Be need to put the 330 ohm resistor and a choke on a switch to auto change them. Distortion and with out. Good job as always! Big thumbs up.

[@mike60510]

Which one will cause the distortion? I just got sound with this schematic and used the 5h choke. Does the 330 ohm resistor change the head room?

[@anvil777]

Honestly Terry, some people are weird. You are practically already selling your amps with hardly any profit and there are still some complainers?! I guess they should check the market a little bit more before they make comments like that. I'm still planning on getting the amp from you.

[@d-labelectronics]

Thanks man, I do appreciate your support

[@chewbactimusprime]

There are people who if you tell them the cost is $10 they'll then ask if you can throw in a guitar cable. And some people fail to grasp the concept that more often than not, DIY doesn't mean cheaper. Sometimes. Most of the time, no.

[@jameswallace5967]

Alcohol and high voltage are a great combination!

[@joseislanio8910]

Parts may be cheap (and good ones aren't) but to get all of that knowledge, it takes a lot of time, money and dedication. I build amps, guitars and pedals for myself, but I wouldn't dare to make them for selling. Can't deal with the bs of some costumers.

[@matthewf1979]

That power transformer is a Triad, 831 EIA code. If it had a 5v winding it would be worth a few hundred bucks. Triad transformers were in the tweed Fenders.

[@d-labelectronics]

Cool deal man, Guess I shouldn't have opened my big mouth. 6 MR-10's sold this morning BUY IT NOW on ebay. I wonder why? haha. Have fun all! TD

[@mike60510]

I was one of those six!

[@6JM6tube]

Good idea putting the volume control at 6F6 g1 for this basic amplifier. Little draw mistake in the preamp tube so have changed the g2 and g3. If you made another one and change the volume at the input have a small 3W 6F6 stereo amplifier with delicious cute sound. Your videos are very interesant. Thanks for share. Like

[@williamjenkins9423]

@6JM6tube Does the g2 / g3 issue refer to the 0.047 uf and 22uf capacitors?

[@AndyWragg]

Great little amp there Terry. Us boys in the UK might have to scratch around for those 2nd hand parts though. ATB

[@Chingu-nm6wp]

cool project really cool sound

[@charlesbickenheuser8281]

Super build. Thanks for sharing..

[@prophetsnake]

Thanks Terry. Great project! I enjoy all of your videos and never fail to learn something from each and every one.

[@tiki_trash]

Screen and suppressor grid circuits are switched on your schematic.

[@williamjenkins9423]

Pins 3 and 6 are numbered the wrong way around on the 6SJ7.

[@cbmikey]

I just picked up an MR-10 at a yard sale. It powers on and the tubes still have plenty of glow in them. Not sure if I should restore the radio or cannibalize parts to build something else!

[@nusior]

This is so simple and cool! Thanks for the idea!

[@sajyho1988]

6G6 is also a nice low watt pentode, maybe a 5W 1959 SLP!

[@evananderson8452]

Another great video Terry. How about one about a cheap transistor version or, if you've done it already then point us to the link. Thanks

[@Finom1]

I just went to your website very cool!!!

[@Bloozestringer]

Terry, any concern using the 6X5 since they seem to be a bit notorious for shorting and killing power transformers. Maybe add a small filament transformer for just the 6x5 and leave it ungrounded?

[@moodyga40]

great circuit i going to build this i will use 6AU6 as the input tube

[@d-labelectronics]

Cool deal, let me know how it turns out

[@randytaylor6931]

This is really cool.

[@d-labelectronics]

This Raven amp #1 has sold. I have the 2nd one complete. It will be ready for flight soon

[@johnsimms3957]

That's a nice looking amp!

[@RPMechanics]

That is very nice. Would love to build one.

[@HarpinJScott]

Thanks Terry...both Regency MR 10s that were on eBay sold within an hour after you posted this video! Arrrgh! 😐

[@d-labelectronics]

Try a MR-33, same chassis

[@d-labelectronics]

reverb.com/item/4528852-d-lab-raven-6f6-3-watt-tube-guitar-amp-head-black-wrinkle-cabinet-vintage-tone-boutique-2 Raven, SN2

[@HarpinJScott]

Thanks Terry! You just answered my next question...is that a crystal ball goblet you're sipping from?!

[@vriolo123]

As an absolute amateur i have no idea what the other components in this video were. Would you mind giving me a list of the other components. I would appreciate it very very much. Have a great day.

[@JackstandJohnny]

Could you please make a video on how to build a tube amp using say, a transformer that can be recycled from a microwave oven and other components that can be found in old household items and modern day, easily and cheapily obtainable and mass produced parts? This is fascinating.

[@RussellCatchpole]

Fantastic video thankyou, I will definitely try this one day!

[@dhpbear2]

I assume you'd switch to 'diode' operation AFTER the tubes have warmed up!

[@umajunkcollector]

ain't this somethin! nice utility amp too, WTG D Lab.

[@Finom1]

Thank you, great educational video!!!

[@Bleats_Sinodai]

I would like to see you try building another Raven Amp, but with one of those DC-DC Step-up modules instead of a power transformer, so it could be powered off batteries or a laptop-style power brick. Also, you could run both the transformer version and the module version through your frequency analizer, and we could finally put to rest (or not) the argument I've seen around, that the power supply can affect the frequency response of an amp. That would be interesting to see.

[@Bleats_Sinodai]

Also, just an observation for that pentode preamp: if you connect the capacitor from the screen grid to cathode, instead of ground, you get a little bit more gain.

[@d-labelectronics]

Cool deal man, I will give that a try

[@DennisMurphey]

Awesome I can do that ! But is it possible to up the power a tad. What size speaker should this little run. Were you using an old radio cabinet in the test video at the end? Could this be put on top of a old Fender Solid State? is that in the other videos. Hey, great stuff, I am ready to try. Can we add a spring Reverb tank to this guy??????

[@74dartman13]

Thanks for all the info. and video!

[@drplasmodius]

Thanks for sharing this Terry. They will probably start showing up soon on ebay in large numbers unfortunately.

[@fullstop213]

Very nice Terry!! Thanks for sharing and I would like to get the schematic :)

[@d-labelectronics]

Please send me you e-mail thru d-labamps.com I will get the schematic right out. Td

[@williamjenkins9423]

I managed to get a screen grab directly from the KZbin video

[@stepsofashaman...4283]

great video.... are there other tutorials for bigger amps? or is there a way to rebuild a solid state amp, to tube

[@fredscott7534]

I just built this amp. Best sounding amp I've ever put together. However, Once the the volume hits about 6, I get a high pitched whine or squeal. The volume pot that I'm using is only 750k, not the 1 meg listed in the schematic. I was wondering if I should use a grid stopping resistor in this circuit at the grid of the 6f6. And if so, what value should the resistor be?

[@RobertKohut]

Great video. You didn't put it on your new fangled tester thing and show us the response curve.

[@d-labelectronics]

Hello, I plan to as well as a simple video showing scope connections to various parts on the amp for troubleshooting.

[@matteomancini5891]

Hi Terry, good video , but one thing i cannot get. Your 6x5 rectifier tube has a capacitor limit to 4 uF, why have you placed a 47 uF ? Any drawback due to it ?

[@TheAdjacents-ABQ]

But what if we are type who would burn the house down constructing one of these and would prefer to have it built for us?

[@MrFosamax]

Muy bueno! Hermoso amp! mis respetos!

[@williamjenkins9423]

If I use an output transformer that has a primary impedance of 8K, would I be better off using a 6V6 output valve?

[@kaspargrayson6074]

is there a parts list???

[@dhpbear2]

Wrinkle-finish aluminum? Terry, you really DO bump into a lot of unique items! :)

[@jargero8203]

They make this "valve cover" spray paint and sell it at every local auto parts store....just spray then bake in your oven

[@DollySvengali]

Sure wish there was a way to diy your own transformers out of something super easy to obtain.

[@agustiankneifel7376]

Hi Terry, can you please tell us, how the ground should be installed? Normally, I used star grounding. I see that you don't use it and works fine to the amp. I am going to build one :-) Thanks

[@cheezemanrich]

Why didn't you use the output transformer from the MR-10? Not enough power handling? Limited bandwidth? Wrong speaker impedance? Wrong impedance for the 6F6? I'm very curious.

[@blediffecannell162]

What is the advantage to using valve rectification over solid state diodes? There must be one or you wouldn't have made it switchable and "wasted" a tube on it for a new design.

[@d-labelectronics]

Tube rect's provide a voltage drop (sag) where-as diodes are stiff with little loss. Each provides a different sound for the amp. So, I like to add a switch for mode select. TD

[@chrisw5742]

How about a tube PA power amp?? Possible?

[@whynotme5926]

Thanks-I was thinking about building this, some of the values are too small for me to read.I think I figured it out. There is one resistor, I can't tell if it is 1.5 or 15 coming out of the cathode of the 6sj7.

[@d-labelectronics]

Hello, That is a 1.5K resistor

[@whynotme5926]

Thanks. for the info-Somebody is buying all the regencies, I always miss the deals, guess I'm just too slow!!!!!

[@rimmersbryggeri]

Is it possible changing this for 240v line power?

[@williamjenkins9423]

Use a Hammond 369EX power transformer and a Hammond 1760C output transformer. On the output transformer, cap off the 5K on the primary and the 3.2 on the secondary (you can use a jack socket for both the 8 ohm and 16 ohm).

[@larry6686st]

Very nice! Can I use a 245-0-245 transformer on this circuit? And maybe raise the bias resistor?

[@d-labelectronics]

Yes, that would be fine

[@dazzlenconfused]

If I cant find a 6sj7 what would substitute for one or could a replace with a 12ax7 ?

[@chattanoogaguitarworksguit7956]

Could I use a 10w OT and everything else the same? Cheers!

[@Tileman69]

Hello to everyone following this build. I'm in the process of collecting parts and I am unsure what 5 Henry choke to purchase. Some guidance please.

[@TanM]

If you have access to a LCR meter, you can wind your own choke ! But may take a feew trials before getting the perfect inductance of 5H though. Good Luck!

[@dazzlenconfused]

Hi terry is there anyother OTranny that you could use like a 5K Primary with / 6/8ohm Secondary just yours has 8ohm sec only thanks from new zealand

[@williamjenkins9423]

You could try the hammond 1760C. It has primary of 5k and 8k, and has 3.2, 8 & 16 ohms secondary.

[@shirazs8882]

I can't seem to find a decent MR-10, but I do see other Regency radios like the ACT-R 10. Do you think that would work? Are there any other radios or equipment where this transformer can be sourced?

[@jaycee30865]

Killer. Thanks. Question though: tube rec for a single ended class a amp offers nothing other than a reduction in b+ right? There is no sag at high output due to class a always drawing same current no matter the output volume?

[@CitizenCS]

Your my new best friend!

[@briandouglas41]

Is it possible to build a home audio amplifier form an old guitar tube amplifier

[@raymondheath7668]

Great!

[@jordanch68]

This is a great project! Is there another recommended option for the power transformer? Thanks, Chris

[@d-labelectronics]

Hello, any 400vac, CT tranny with 6V for heaters will work. Try to make sure the HV is at least good for 50-70ma. TD

[@jordanch68]

Thanks for the info! MR10's are going up up and away right now. :)

[@mike60510]

Thanks for the transformer recommendation. I purchased and salvaged a one from a Regency MR-10D Monitoradio. The transformer in your video is model C500-160-3. The one I pulled is a model 500-802. The unit I pulled the transformer from powered seven tubes puts out 384 volts at the secondary side. Is there a test I can do to see if it is able to provide at least 50 mA or would I need to find spec sheet on the transformer? Thanks again, I really enjoy your videos.

[@jordanch68]

I've ordered a couple custom transformers from China. An R-core and a torroidal, it'll be interesting to see how they do.

[@williamjenkins9423]

Could use a Hammond 369EX power transformer.

[@hrjr2283]

good info. will a fender champ output transformer work for this amp?

[@d-labelectronics]

Yes, as long as it is a standard 5K SE Type

[@hrjr2283]

thanks Terry.

[@g.sferrazza10-13]

can it handle effect pedals?

[@xdx2653]

hello nice job i have a problem with my new amp its the evh lbx 15 watt head when i hit the preamp tubes with a wooden stick i hear a big noise.that happened at v3 (low noise),v2 (more noise) and v1 (very high noise).i put new tubes but same problem :( please help me

[@d-labelectronics]

Sounds like cracked solder connections or microphonic tubes

[@xdx2653]

ok ty i will open the amp and i try to fix it :)

[@haroldmitcheltree518]

LOOKING at your schematic, you show 1M & .047u connected to G3 and NOT G2 - G3 should be connected to the cathode: pin 5. Also, pin 1 of the 6SJ7 should be grounded - that's the shell & will help with hum reduction.

[@Tileman69]

Hello Harold, you seem knowledgeable about this circuit. Could you give me help me choosing the right choke? All of the 5 Henry chokes I've found are well under 330ohm. This is my first amp build, any help would be appreciated, Thanks.

[@haroldmitcheltree518]

@@Tileman69 If i were building it, I'd use a Fender 4H 90mA as they are common, inexpensive, with more than adequate ratings for this application.. IF you MUST have the 5H part, then a Hammond 157L (5H 75mA) will also work.

[@haroldmitcheltree518]

@@Tileman69 - go here for schema: www.dropbox.com/sh/hn82tch76aoc8wd/AAAGpSXR5hXC42w3NvdEMCBsa?dl=0

[@Tileman69]

@@haroldmitcheltree518 Thank you.

[@haroldmitcheltree518]

@Bob Olsen Check that link again. Schematic with a single knob TS added.

[@jeebusyaweirdo3733]

Do you ever build custom amps for people?

[@wadehicks9270]

3 watts of tube power would really surprise a person just how much kick its got.

[@PeterDad60]

I cobbled together a 1 watt tube guitar amp and it can be loud. Won't damage your hearing kind of loud, but still loud.

[@chokkan7]

Thanks for another great video, Terry.I just realized that with a buzz cut, you could be another Walter White...hope you're not building these amps in an underground lab somewhere...:)

[@3xgamer688]

Nice

[@YourLastChance]

Hi, Terry. What size of chassis is needed for a guitar tube guitar practice amp head (12AX7, EL84) ?

[@d-labelectronics]

I always size them to the cabinet. Do you have one in mind?

[@YourLastChance]

Yes, in future. Maybe 10" x 1

[@accwarr]

Hello ... i have a cort 15 watt amp ... while playing it suddenly stop and dont work again until i unplug the guitar and touch the caple jack to make it buzz then it may work or need to touch it again ... can you tell me please what is wrong with it ... i know its cheap crap amp but its all i have :D :D

[@d-labelectronics]

Hello, my 1st guess would be cracked solder joints on the PCB. So, you will have to pull the board, inspect under a magnifying glass, touch up connections. Pay close attention to joints on the controls/jacks/power components. TD

[@accwarr]

ok i will give it a try ... another thing please , can it be a tube amp or it is difficult as its parts are cheap ..and do you have a facebook account ? :D :D

[@d-labelectronics]

It could be the pre-amp tube. Yes, I have a FB, just search for d-lab electronics

[@essentialedm937]

I am trying to build my own 12au7 headphone amp but am not having much luck as it doesn't function correctly. I followed a schematic, would you be able to help me?

[@larry6686st]

Hi Terry! Can you ask your guitar player to play the theme song on the TV show Cheaters? 😂

[@jeromegrzelak8236]

SWEEEEEEET

[@YeeThirty]

Id pay $200 for one.. if i didnt know how to solder and read schematics :p R.E. power transformer.. hammond makes one with similar specs. PN: 269EX

[@curtiseverett1671]

you are missing the stem on your wine glass