2:49 Condition of exterior 7:08 Removal of back panel 10:32 Evolution of Bandmaster circuits (w/ schematics) -10:32 Tweed 5E7 -12:03 Blonde 6G7 w/ harmonic tremolo -15:01 Blonde 6G7-A w/ 5 triode harmonic trem -18:55 Blonde/Blackface AA763 dual triode photoresistor 17:27 5881 vs 6L6 vs 6L6GC (Power tube comparison) 22:17 Under the hood 22:46 Transformer oddities 26:51 Removal of dog house 25:50 NOS preamp tubes 28:21 The chassis 31:11 Screen resistors 31:51 Removal of cathode bypass caps 34:18 Amps first power up (testing each channel w/ signal generator; current limiter, and bias probes in place) 38:26 Biasing the tubes (addressing a depleted cathode in a power tube) 39:56 Bias / calculations data for tubes (plate dissipation, 20% tube matching, 70% Plate dissipation vs. 50%-60% dissipation) 47:17 Pilot light (#47 6V bulb) 47:37 Tremolo stops oscillating 47:57 Testing capacitors in a circuit 47:46 Replacing capacitors in a trem circuit 51:45 Audio demonstration
@@UncleDoug This synopsis is the icing on the cake. Your videos have a lot of critical information about these older amplifiers, and I thank you for taking the time to document this kindof stuff. Hope all is well on your end!
@Uncle Doug 1:05:49 Love your tune w/the drone video. It has that indelible 60’s American garage spirit. I’m a subscriber & enjoy learning about amps the way you go through them thoroughly & well explained.
PS: I’ve got a c.‘62 blonde Bandmaster that has a repeating “knock” sound when Vibrato is running. My knowledgeable amp-tech friend couldn’t seem to remedy it. Any ideas? Thanks! 🙏🏼 Dave/Seattle
@@surfercrow This is not an uncommon problem, SC, in fact my own brownface Concert amp had a similar thump. I would recommend a thorough checking of all the voltages in the "vibrato" circuit, as well as the status of the capacitors, particularly those used for coupling of stages.
Watching your vidoes for a little now. Love the way you teach. I'm an auto tech at a dealer and I can appreciate the quality and attention you give. Thank you very much for the knowledge. I've already fixed a couple problems with my dsl40c with that knowledge you passed on.
Videos like this should be permantly installed consecutively to a media unit wired to 60 inch screen tvs in every great museum and music store on earth. Thankyou for another adventure Vid sir!!! Back to watching.....
I briefly possessed a 6G12 Fender Concert that has that same tremolo circuit. Much to my horror it turned out to have been a stolen amp that I purchased on Craigslist. So of course I returned it. It was an amazing sounding amp. I completely fell in love with the sound of it. I've got almost all the parts to build one now.
Man those old Fenders have such a musical vibe. They even seem to balance string output. Thanks so much for all the work you do on these videos. Just the right amount of technical/historical & humorical.
Uncle Doug, you may remember a 5 digit phone number, but I remember as a kid back on the farm in Northeast Missouri we had a 3 digit phone number on a crank phone. Our number was two shorts and a long. And that was with the old party line phone system. This was back in the early to mid 60's. I think it was somewhere around 66 to 68 before rotary dial became available in our area. Still a party line. What a pain that was! What a find this amp is, just makes you drool and wish it was your own amp. Great video as per usual Sir!
@@UncleDoug Yes, I agree Rural areas always seem slower implementing new technology. I was back on the farm in the late 90's to visit my dad before he died and they still had a rotary phone system in that area. At least the party line was gone by then. They had a touchtone phone on the wall but the little switch on the side was set to rotary not tone dialing. I remember having to use a handheld touch tone generator on the mic in the phones headset to be able to access the companies systems that I worked for at the time when trying to access company apps & files etc..
Ha ha! That amp is exactly three years older than me, how cool is that! Speaking of cool, the sound of a harmonic tremolo is much more complex than the standard type. Thanks so much for another awesome and informative video!
Best amp videos on the internet hands down. Finding a new Uncle Doug videos make my day. And what a killer amp. I’m a sucker for blonde piggyback Bassman, Tremolux & Bandmasters. Classiest looking amps imo. Really love the oxblood grill cloth versions from 1962
Fantastic video of this rare '63 Blonde Fender Bandmaster. Only amp ever regret selling in my life was my 1964 Blackface Fender Vibro-Lux. The tremolo and amp had that full vintage analog warmth and tonality...like this '63 Bandmaster beauty.
Another winner of an episode, dear uncle. I am however, flummoxed by the unusual designation numbers on the power transformer. Your supposition of how it possibly wound up being installed is probably correct and logical. This Band Master is as close to mint as humanly possible! I am a huge fan of the 5881 output valves. Here lately, the only U.S. manufacturer using them almost exclusively is Soldano. His high gain amps are wrought with the 5881 power section. Thanks again for a great session; in bringing this mint exterior amp to a mint tone! Although the audio test instruments were well considered, I was dying to hear a strat, or tele through it as well. Nevertheless it sounded as it was in 1963; clean, responsive, and honest. Enjoy your Labor Day weekend, and thank you for the aerial panoramic of that picturesque park. Speak soon...
Thanks for all your erudite comments and observations, Alex. I too am a big fan of vintage 5881 tubes, but they are getting rather scarce. I wish I had stocked up on them back when they were more plentiful. Have a great weekend.
There is something relaxing and enjoyable about watching Uncle Doug’s presentations even though I hardly understand half of the technicalities of the amps.
PS. This is really awesome, I don't want that to get lost with my ramblings- This video especially for me, but these in general are a cataloguing of history and you are truly doing the world a service by documenting these beauties and their inner workings. Especially this era- there is an ever increasing ignorance out there about the brown face era. Sir, you are a gentleman and a scholar.
I almost bought this amp on Reverb. I ended up buying another late 63 bandmaster head. Beautiful amps. Great work going over this amp for the customer man.
I thought that was what was going on. I guess in this case Leo got the vibrato part right. I guess I'll never understand how he got the terminology mixed up.
@@UncleDoug I might add your playing has grown stronger over these years. The riffs your playing lately make these amps shine. Amp's are great but its still in the fingers.
Thank you So Very Much! I am not an amp tech or a luthier. I am a third generation engineer and I do my own work. But that is only background noise. What I wanted to say is this. I have been subscribed and loving it, but the past four or five videos I find that I can read the circuit! AND I LOVE IT! I mean I am looking at the schematic, and then the breadboard and I can tell what I am seeing. Which to you is obvious But the difference is the way that you are teaching it. When the trem went bad I remembered the flyover view of the circuit and could visualize where those suspect caps were. And that felt great.
Congratulations on your acquisition and retention of knowledge, Kenn. It's a cumulative process, so keep up the good work.....and you will be thrilled with the results.
A wonderful video to watch for learning and enjoying! All the joy of the electric guitar comes when you really understand the amp. Thanks uncle Dough! You teach to learn love thy work.
Watching your vids has definitely inspired me to do a modification on my Vox ac15, myself. I added a new jack plate and two female 1/4” jacks to be able to use an attenuator with my Combo amp. I even used one switched female jack so that I wouldn’t need to use a short jumper cable between the two when not using the attenuator. Thanks for sharing your great work
Thank you for highlighting Studio Sound Electronics. I have been looking for parts for my GA-30 RVT INVADER. This site will help immensely. The education and entertainment in your videos is always appreciated.
Doug, what a great amp! I'm very glad is was so pristine! It sounds really good through the shop speaker! Thanks for the P90 and humbucker demos. Reminds me I need to get a P90 guitar close to me again! Jack and Ollie are sounding great as ever! I really do need to get a vintage Fender amp, or at least a proper Fender circuit. Also really enjoyed the drone flight. I live north of DC now, but grew up in Las Vegas. Like 50 years ago. I really miss the desert!
Yeah P-90s are so disregarded and under appreciated. I wonder if some folks lose sleep over routing out vintage Lesters back in the day to make way for a humbucker? I witnessed more than one orig Les Paul have its P90 discarded for p.o.s. Dimarzio back in the mid 70's! The blasphemy, may such wrongful souls rot in Disco Hell!
Great and informative video, thanks again Uncle Doug! I have a '62 Blonde Bandmaster I acquired in 2005 and it's the amp that I've had longer than any other of my amps, and I've literally had dozens. I first got to use one of these in a studio session in 2002 or so and fell in love with the harmonic vibrato effect immediately - as well as with the way the amp breaks up when pushed. After the session I promised myself that I would purchase a similar amp no matter what the cost. A couple of years later I finally ran into one and here we are together after 15 years. It's a remarkable amp and still brings me a lot of joy! Mine is an export model that runs on 230 V mains voltage, the transformer codes (power, output and choke) are J022822, 022848 and 125C1A, respectively. Mine also has the thick "dogbone" handle. A couple of years back I ordered a matching 2x12" cabinet for it since I found a beautiful matching pair of period-correct Jensen C12N speakers from 1963. Here's a little more info and a lot of pictures in case someone is interested: jucciz.com/?section=amps&page=6g7-a All the best from Finland!
@@UncleDoug I can really see that! Even though I'm not an electronics expert, the way you break things down in your videos makes it very easy to follow what's happening - and I've surely learned a lot along the way. Thanks a bunch!
Hi Uncle Doug... Sounds like you have been practicing you're licks!!!!! Another Super Quality Job! That little Cabinet kicks you know what. I prefer the sound of the P 90's Through that amp. As usual Thank You!!!
So look forward to these new arrivals of yours Doug..! Lovely to see these old jewels as you call them. Great vid, repair and service..Learning loads, and I'm sure that customer will be so happy to have had his amp star on your channel..Thanks for sharing your knowledge once again..Ed..U.K.
Thanks, Shaun. I've started asking for letters with the amps so I can see exactly what the owner's are looking for. Just wait until the next video, featuring a 1954 Gibson GA-77.....I really felt like I delivered on the owner's requests.
Hello Uncle Doug, Well, that was almost to easy, you have fixed harder, but, this one sure was in nice condition, beautiful. Always good to see an amp video, they are what your famous for, I'm sure you'll be famous for your fine work on Hot Rods as well. Nice to hear the Cat's play some guitar, Petty at that. Glad your doing well, me too. Nice scenery and music, I take it that's you on guitar? Thank you for all the years of great instructional content and entertainment. Enjoy the last day's of Summer, all the best, Cass.
Gorgeous sounding amp!!! I love how it responds to the P90's in specific. Great rebuild Doug, and cool "reverse engineering" ideas about the odd transformers, etc. What a beauty
Yes it appears to be much more fluid and analog like. Never noticed the slightest tick like opto! But amazingly complicated circuit for what it does and with a potential to generate spurious RF interference too.
I bought an old 6G7-a Bandmaster about 25 years ago. It had been recovered in snakeskin-patterned tolex. I had it rebuilt by Kendrick Amplifiers. When I came to pick it up, Gerald Weber said he was gonna have to give me a Valium before we fired it up, because it sounded so good.
Uncle Doug , I wasn’t familiar with the harmonic tremolo sound until I heard that Bandmaster after Kendrick restored it. That sound is simply gorgeous. I had driven to the Kendrick factory on my lunch break to pick up the Bandmaster, and after hearing it, I had to take the rest of the day off and be alone with it for a while.
Another wonderful video! In the next sound test, I would love to hear one of these beauties turned up to about 5 or so. That way, in addition to the wonderful clean tones, we can experience some of those delicious breakup sounds that the brownies are famous for.
That's one hot blonde! But that harmonic tremolo is just magnificent...probably the most watery and rich I've ever heard. Such a great production from start to finish on this one Doug. 👍
thanks for the effort you put in to bringing us these videos uncle doug, its pure genius, always leaves a big smile on everyones face i`m sure! as captain ahab said to mr starbuck,"let me look into a human eye "
Great videos! , very helpful when I get this old fender's in for repair👍 Glad you mentioned the thing about plate dissipation. I have experienced the same thing that 70% isn't always right when I built a 200 watt bass amp for a couple years ago, using 4x kt88 at 650 volt plate voltage. I biased the amp at 70% plate dissipation.,everything looking good. Then I plugged in a dummy load and a signal generator and suddenly the kt88 starts to redplate at only 140 watts output! Aftar a long time fiddeling with the bias I ended up at 21% plate dissipation before I could run the amp at full power without red plating. The signal was looking beautiful on the scope, no crossover distortion even at 180 watts.. So my conclusion is that plate voltage and transformer impedance is the decisive factors when it comes to plate dissipation. But I am no expert, just learned by doing😊
Excellent. Your videos have been an excellent guide for me while I have been learning about fender circuits. I have an old bassman head in quite a state, and I will be diving in to overhaul it this weekend. I don't think I would know nearly enough to do this safely or to a decent standard if it wasn't for channels like this.
@@UncleDoug just to let you know, an absolute success. Amp is repaired, in safe stable working order and just needs minor tweaks from this point. A complete recap, new heater wiring, new power screen and bias resistors, new plate resistors, some other replacement parts and reversal of poor shoddy previous work. Thanks again for your excellent resources, couldn't have done this myself without you!
Another masterful exposition, Uncle Doug. I love the math and that you use the data to drive your actions. Also, love the geekery inducing that Fender probably ran out of transformers, given the transition of this circuit to another. Rock and roll!
Great job Doug. Amp sounds amazing. I vote p-90s, but I'm a single coil guy on Thursdays, Saturdays, and Mondays. Thank you, sir. Cats are sounding good too. Really like the drone flights and the music.
Wonderful video, such a thorough and detailed, very clear explanation of this remarkable piece of vintage tech... great stuff! Thanks for making this video!
That is one nice amplifier Doug! The owner did very well on his selection! I saw video of the Beach Boys live and they were using a lot of blonde piggyback Fenders. Leo must've been in great delight seeing his amps being played on world wide television! Great Job and say Hello to them katz!!
The 125A6A on the output makes sense. The power transformer (to my eye on the video, I could be completely wrong), looks like it's a re-stamp of a 125P1B (another common Fender Power Transformer), i.e. it looks like the 1 was stamped over to a 7. Beautiful wiring. Amazing amp and video as always.
As an old Fender fan (76) I can say that the bandmaster was one of the amplifiers with the best sound at the time.in conjunction with a 15 "Lansing loudspeaker and aDynacord or Echolette echo device that was an absolute top soundthat I still have in my ear to this day, together with a Stratocaster, of course.
@@UncleDoug I agree! For fixed bias amps I'll often bias them to 50-60% PD for guitar. For blues harmonica you can get away with being biased even colder... I have an amp I built ftom an old 1963 Linear L50 PA amp which now largely follows a 5F6-A schematic. It runs about 540V on the plates of the 6L6GC's but I have it biased around 20mA. For cathode bias I still prefer warmer bias settings.
![Uni-Vibe Vs Harmonic Tremolo [Plus Fuzz & OD Order]- That Pedal Show](http://i.ytimg.com/vi/X3Pzufv7TT8/mqdefault.jpg)
2:49 Condition of exterior
7:08 Removal of back panel
10:32 Evolution of Bandmaster circuits (w/ schematics)
-10:32 Tweed 5E7
-12:03 Blonde 6G7 w/ harmonic tremolo
-15:01 Blonde 6G7-A w/ 5 triode harmonic trem
-18:55 Blonde/Blackface AA763 dual triode photoresistor
17:27 5881 vs 6L6 vs 6L6GC (Power tube comparison)
22:17 Under the hood
22:46 Transformer oddities
26:51 Removal of dog house
25:50 NOS preamp tubes
28:21 The chassis
31:11 Screen resistors
31:51 Removal of cathode bypass caps
34:18 Amps first power up (testing each channel w/ signal generator;
current limiter, and bias probes in place)
38:26 Biasing the tubes (addressing a depleted cathode in a power tube)
39:56 Bias / calculations data for tubes (plate dissipation, 20% tube matching,
70% Plate dissipation vs. 50%-60% dissipation)
47:17 Pilot light (#47 6V bulb)
47:37 Tremolo stops oscillating
47:57 Testing capacitors in a circuit
47:46 Replacing capacitors in a trem circuit
51:45 Audio demonstration
Wonderful synopsis, LR. Thanks again :)
@@UncleDoug This synopsis is the icing on the cake. Your videos have a lot of critical information about these older amplifiers, and I thank you for taking the time to document this kindof stuff. Hope all is well on your end!
@Uncle Doug 1:05:49 Love your tune w/the drone video. It has that indelible 60’s American garage spirit. I’m a subscriber & enjoy learning about amps the way you go through them thoroughly & well explained.
PS: I’ve got a c.‘62 blonde Bandmaster that has a repeating “knock” sound when Vibrato is running. My knowledgeable amp-tech friend couldn’t seem to remedy it. Any ideas? Thanks! 🙏🏼 Dave/Seattle
@@surfercrow This is not an uncommon problem, SC, in fact my own brownface Concert amp had a similar thump. I would recommend a thorough checking of all the voltages in the "vibrato" circuit, as well as the status of the capacitors, particularly those used for coupling of stages.
Watching your vidoes for a little now. Love the way you teach. I'm an auto tech at a dealer and I can appreciate the quality and attention you give. Thank you very much for the knowledge. I've already fixed a couple problems with my dsl40c with that knowledge you passed on.
Thanks, Joe. I'm glad the videos have been helpful :)
I just love seeing and hearing the repairs and upgrades to these circuits. Thanks for bringing us along Uncle Doug!
You bet, GG. We enjoy your company :)
I approve this message... lol🙋♂️
Videos like this should be permantly installed consecutively to a media unit wired to 60 inch screen tvs in every great museum and music store on earth.
Thankyou for another adventure Vid sir!!!
Back to watching.....
Wow.....high praise indeed, Scott. Thanks !!!
I briefly possessed a 6G12 Fender Concert that has that same tremolo circuit. Much to my horror it turned out to have been a stolen amp that I purchased on Craigslist. So of course I returned it. It was an amazing sounding amp. I completely fell in love with the sound of it. I've got almost all the parts to build one now.
I'm glad you were honest, Pete. It's the best policy.
Great sounding amp! Marshall's going to love that amp.
Let's hope so, Mike :)
I mean, he loved him a Bassman, so I see no reason why a Bandmaster should be any different!
Man those old Fenders have such a musical vibe. They even seem to balance string output. Thanks so much for all the work you do on these videos. Just the right amount of technical/historical & humorical.
Thanks, Clarence. Being balanced in today's world is getting to be a real challenge :)
What a pleasure that was checking out in depth that model. Thanks Uncle Doug!
Thanks for joining us, FF :)
Uncle Doug, you may remember a 5 digit phone number, but I remember as a kid back on the farm in Northeast Missouri we had a 3 digit phone number on a crank phone. Our number was two shorts and a long. And that was with the old party line phone system. This was back in the early to mid 60's. I think it was somewhere around 66 to 68 before rotary dial became available in our area. Still a party line. What a pain that was!
What a find this amp is, just makes you drool and wish it was your own amp.
Great video as per usual Sir!
Thanks so much, Duncan. I think the phone system developed a little slower in rural areas.
@@UncleDoug Yes, I agree Rural areas always seem slower implementing new technology. I was back on the farm in the late 90's to visit my dad before he died and they still had a rotary phone system in that area. At least the party line was gone by then. They had a touchtone phone on the wall but the little switch on the side was set to rotary not tone dialing. I remember having to use a handheld touch tone generator on the mic in the phones headset to be able to access the companies systems that I worked for at the time when trying to access company apps & files etc..
Watch another fantastic repair of someone's now finely restored Fender amp. Thanks for sharing your process and progress of doing so Uncle Doug.
Our pleasure, HM :)
Ha ha! That amp is exactly three years older than me, how cool is that! Speaking of cool, the sound of a harmonic tremolo is much more complex than the standard type. Thanks so much for another awesome and informative video!
The pleasure was ours, Wade :)
Best amp videos on the internet hands down. Finding a new Uncle Doug videos make my day. And what a killer amp. I’m a sucker for blonde piggyback Bassman, Tremolux & Bandmasters. Classiest looking amps imo. Really love the oxblood grill cloth versions from 1962
Thanks so much, VK......glad you enjoyed the video.
Fantastic video of this rare '63 Blonde Fender Bandmaster. Only amp ever regret selling in my life was my 1964 Blackface Fender Vibro-Lux. The tremolo and amp had that full vintage analog warmth and tonality...like this '63 Bandmaster beauty.
Thanks, Daniel.
God Bless and Protect you and your wonderful family Uncle Doug. Thank you for sharing your wisdom with us.
Thanks so much, F1. Likewise to you and yours.
And that circuit came out perfect, with P90's you had no noise which is unheard of. Another phenomenal restoration/fix up !!
Thanks so much, Bert.
Another winner of an episode, dear uncle. I am however, flummoxed by the unusual designation numbers on the power transformer. Your supposition of how it possibly wound up being installed is probably correct and logical. This Band Master is as close to mint as humanly possible! I am a huge fan of the 5881 output valves. Here lately, the only U.S. manufacturer using them almost exclusively is Soldano. His high gain amps are wrought with the 5881 power section. Thanks again for a great session; in bringing this mint exterior amp to a mint tone! Although the audio test instruments were well considered, I was dying to hear a strat, or tele through it as well. Nevertheless it sounded as it was in 1963; clean, responsive, and honest. Enjoy your Labor Day weekend, and thank you for the aerial panoramic of that picturesque park. Speak soon...
Thanks for all your erudite comments and observations, Alex. I too am a big fan of vintage 5881 tubes, but they are getting rather scarce. I wish I had stocked up on them back when they were more plentiful. Have a great weekend.
There is something relaxing and enjoyable about watching Uncle Doug’s presentations even though I hardly understand half of the technicalities of the amps.
Thanks, Jeff :)
Another excellent lesson. Thanks...bonus that the amp was made/completed on my 6th birthday.
Wow....lots of people's birthdays coincided with date codes in this amp. It must be magic !!!
PS. This is really awesome, I don't want that to get lost with my ramblings- This video especially for me, but these in general are a cataloguing of history and you are truly doing the world a service by documenting these beauties and their inner workings. Especially this era- there is an ever increasing ignorance out there about the brown face era. Sir, you are a gentleman and a scholar.
Wow, thanks so much, SC. It's a partnership between us and our viewers, who send us these beauties for repair.
Thanks for the great video, Uncle Doug. Thanks to your UA-cam videos I have been able to tune up several Fender tube amps.
You're welcome, Andy. Glad to hear that the videos are helpful.
I don't usually listen to the entire audio test for amps, but this was an exception. What a sweet sounding amp!!
Thanks, Jim :)
Brought back memories of my 1962 'The Twin" ...good times
Doug, you are truly blessed with awesome patrons and viewers.
Indeed we are, Richard, and I am truly fortunate to have them.
That’s got to be one of the best sounding amps you’ve worked on Doug. Excellent work as usual 👍
Thanks so much, Chris :)
It's always a privilege to hear Jack and Ollie play...
Thanks, Eddy. They really appreciate hearing from their fans.
It is amazing how their paw spikes and pink pads never get in the way or deaden notes ...
I almost bought this amp on Reverb. I ended up buying another late 63 bandmaster head. Beautiful amps. Great work going over this amp for the customer man.
Thanks, KK :)
I love watching Uncle Doug! This amp is a real looker! Love it!
Thanks, DP.
Sounds Great!!! That tremolo is dreamy.
Thanks, William. The frequency modulation definitely gives it a special sound.
I thought that was what was going on. I guess in this case Leo got the vibrato part right. I guess I'll never understand how he got the terminology mixed up.
Uncle Doug, I must complement you on your masterful rubato at the end of the first P90 demonstration. I almost tipped over in my chair. Bravo.
Thank heavens someone out there in UA-cam Land recognized our stunning bit of musical artistry, Larry. We thank you.
Another great one. No B.S. just straight to the heart of the matter. Well Done!
Thanks, John. We try not to waste our viewer's time.
By far the best amp videos online. Love your stuff, Uncle Doug!
Thanks, Luke :)
Hi Uncle Doug. You do some of the prettiest work I have ever seen, and I have been around a while in HF amp and radio repair.
Thanks so much, Monty :)
Yeah it's pretty much the holy grail with the speed and the intensity up. That is one of the most luxurious vibrato and tremolo's I have ever heard
Thanks, Joe. I agree :)
@@UncleDoug I might add your playing has grown stronger over these years. The riffs your playing lately make these amps shine. Amp's are great but its still in the fingers.
Thank you So Very Much!
I am not an amp tech or a luthier. I am a third generation engineer and I do my own work. But that is only background noise. What I wanted to say is this. I have been subscribed and loving it, but the past four or five videos I find that I can read the circuit! AND I LOVE IT!
I mean I am looking at the schematic, and then the breadboard and I can tell what I am seeing. Which to you is obvious But the difference is the way that you are teaching it. When the trem went bad I remembered the flyover view of the circuit and could visualize where those suspect caps were. And that felt great.
Congratulations on your acquisition and retention of knowledge, Kenn. It's a cumulative process, so keep up the good work.....and you will be thrilled with the results.
The power transformer in this magnificent amplifier was made the same month I was born. Thanks for sharing all the schematic knowledge.
Our pleasure, James. Regards to that handsome pup in your icon photo.
Uncle Doug, this has been my introductory video to your channel. Wow, to say I'm blown away is such an understatement. Thank you Sir!
You are very welcome, BY. Please watch our other 230+ videos when you get the time :)
Uncle Doug I did notice that I had some catching up to do. Sorry Netflix, you’ll have to wait. 👍
A wonderful video to watch for learning and enjoying! All the joy of the electric guitar comes when you really understand the amp. Thanks uncle Dough! You teach to learn love thy work.
You're quite welcome, Luis. Thanks for your very nice comments.
Watching your vids has definitely inspired me to do a modification on my Vox ac15, myself. I added a new jack plate and two female 1/4” jacks to be able to use an attenuator with my Combo amp. I even used one switched female jack so that I wouldn’t need to use a short jumper cable between the two when not using the attenuator.
Thanks for sharing your great work
You're welcome, WD......glad the videos were helpful.
Man, that Humbucker pickup played through the vibrato channel sounds GLORIOUS. Time to build one of these amps and get me a Humbucker electric guitar.
Thanks, Andy......agreed.
Thanks Uncle Doug! Another great learning experience
That's great to hear, V :)
Thank you for highlighting Studio Sound Electronics. I have been looking for parts for my GA-30 RVT INVADER. This site will help immensely. The education and entertainment in your videos is always appreciated.
You're quite welcome, ReF. Thanks !!!
Doug, what a great amp! I'm very glad is was so pristine! It sounds really good through the shop speaker! Thanks for the P90 and humbucker demos. Reminds me I need to get a P90 guitar close to me again! Jack and Ollie are sounding great as ever!
I really do need to get a vintage Fender amp, or at least a proper Fender circuit.
Also really enjoyed the drone flight. I live north of DC now, but grew up in Las Vegas. Like 50 years ago. I really miss the desert!
Thanks so much, Bill. I think we all need at least one vintage Fender amp ;) The desert really is a special place.
Yeah P-90s are so disregarded and under appreciated. I wonder if some folks lose sleep over routing out vintage Lesters back in the day to make way for a humbucker? I witnessed more than one orig Les Paul have its P90 discarded for p.o.s. Dimarzio back in the mid 70's!
The blasphemy, may such wrongful souls rot in Disco Hell!
Great and informative video, thanks again Uncle Doug! I have a '62 Blonde Bandmaster I acquired in 2005 and it's the amp that I've had longer than any other of my amps, and I've literally had dozens. I first got to use one of these in a studio session in 2002 or so and fell in love with the harmonic vibrato effect immediately - as well as with the way the amp breaks up when pushed. After the session I promised myself that I would purchase a similar amp no matter what the cost. A couple of years later I finally ran into one and here we are together after 15 years. It's a remarkable amp and still brings me a lot of joy! Mine is an export model that runs on 230 V mains voltage, the transformer codes (power, output and choke) are J022822, 022848 and 125C1A, respectively. Mine also has the thick "dogbone" handle. A couple of years back I ordered a matching 2x12" cabinet for it since I found a beautiful matching pair of period-correct Jensen C12N speakers from 1963.
Here's a little more info and a lot of pictures in case someone is interested: jucciz.com/?section=amps&page=6g7-a
All the best from Finland!
Wow, thanks for sharing that wonderful story, Jucciz. You're exactly the type of amp-lover we created this channel for :)
@@UncleDoug I can really see that! Even though I'm not an electronics expert, the way you break things down in your videos makes it very easy to follow what's happening - and I've surely learned a lot along the way. Thanks a bunch!
@@ziccuj You're quite welcome :)
Hi Uncle Doug... Sounds like you have been practicing you're licks!!!!! Another Super Quality Job! That little Cabinet kicks you know what. I prefer the sound of the P 90's Through that amp. As usual Thank You!!!
Thanks for the nice comments, Terry :)
What a beauty of an amp! Thanks for another great video :)
Thanks, Rick.....our pleasure :)
Sir, you do great work!!! You are one of the few I truly respect!!
I appreciate that, Raul. Thanks :)
A nice presentation of the evolution of these wonderful amps awaits inside thanks to Uncle Doug.
Our pleasure, JJ.
I loved the close ups to the controls, showing the actual settings on the amp. Sublime as always Uncle Doug!
Glad you liked it, Fredy.
That presence control is astounding! When you turned it down, my screen went black.
The magic of electronics :)
What a sweet Fender. Sounds fantastic. Another great job Uncle Doug!
Thanks, Carl :)
So look forward to these new arrivals of yours Doug..! Lovely to see these old jewels as you call them. Great vid, repair and service..Learning loads, and I'm sure that customer will be so happy to have had his amp star on your channel..Thanks for sharing your knowledge once again..Ed..U.K.
That's great to hear, Ed. Thanks so much :)
Dang! 5 triode harmonic tremolo, I think is the way to go. Such a luscious and full sound! Thanks for sharing your work.
It was our pleasure, JT.......glad you enjoyed it.
Beautiful amp Doug. You always seem to tailor your methods to the goals of the owner and the condition of the equipment; well done.
Thanks, Shaun. I've started asking for letters with the amps so I can see exactly what the owner's are looking for. Just wait until the next video, featuring a 1954 Gibson GA-77.....I really felt like I delivered on the owner's requests.
Hello Uncle Doug, Well, that was almost to easy, you have fixed harder, but, this one sure was in nice condition, beautiful. Always good to see an amp video, they are what your famous for, I'm sure you'll be famous for your fine work on Hot Rods as well. Nice to hear the Cat's play some guitar, Petty at that. Glad your doing well, me too. Nice scenery and music, I take it that's you on guitar? Thank you for all the years of great instructional content and entertainment. Enjoy the last day's of Summer, all the best, Cass.
Thanks so much for all the nice comments, Cass. If you're referring to the final (drone) tune, yes, it's something I made up years ago.
I love watching your videos Uncle Doug! I find it very relaxing and helps to clear the mind. I have also learned a lot. Sending a hug from Brazil!
That's great to hear, T. Back at you on the hugs :)
Always a good day when I come home and see there is a new Uncle Doug video! Great work as always sir! Amp sound fabulous, should be one happy owner!!
Thanks so much, MP. I certainly hope so :)
Another great video Uncle Doug!!
Glad you enjoyed it, Big Joe. Thanks so much.
Gorgeous sounding amp!!! I love how it responds to the P90's in specific. Great rebuild Doug, and cool "reverse engineering" ideas about the odd transformers, etc. What a beauty
Thanks so much, D :)
@@UncleDoug No, good sir, thank YOU :)
I think the customer is going to be very happy with this! And that vibrato is really nice.
I hope so too, John. Thanks :)
Thanks Uncle Doug. Always appreciate your analysis and in depth history review of these awesome amps.
My pleasure, Kim......so glad you enjoy them.
What a beautiful amp, sounds delicious.
Thanks, Donald.
Oops, meant to say that tremelo sounded great, so smooth and characterfull, worth all the extra components.
Agreed, Rob. Thanks !!!
Yes it appears to be much more fluid and analog like. Never noticed the slightest tick like opto! But amazingly complicated circuit for what it does and with a potential to generate spurious RF interference too.
Another Good one Doug thank you
Thanks for taking us along on this journey, as always very enjoyable and educational.
Thanks for joining us, Kevin.
Great Episode Uncle Doug!!
Thanks, TM :)
I bought an old 6G7-a Bandmaster about 25 years ago. It had been recovered in snakeskin-patterned tolex. I had it rebuilt by Kendrick Amplifiers. When I came to pick it up, Gerald Weber said he was gonna have to give me a Valium before we fired it up, because it sounded so good.
Was he right? How great did it sound?
Uncle Doug , I wasn’t familiar with the harmonic tremolo sound until I heard that Bandmaster after Kendrick restored it. That sound is simply gorgeous. I had driven to the Kendrick factory on my lunch break to pick up the Bandmaster, and after hearing it, I had to take the rest of the day off and be alone with it for a while.
Those gifts are awesome. You reap what you sow. Just awesome.
Yes, they are, RH, as are the wonderful viewers who watch our videos, comment, and send them.
Another wonderful video! In the next sound test, I would love to hear one of these beauties turned up to about 5 or so. That way, in addition to the wonderful clean tones, we can experience some of those delicious breakup sounds that the brownies are famous for.
Thanks, Andrew. I'll keep your suggestion in mind.
Yeah and unkies chops are getting better and better, I think he has been practicing!
Dont be so shy unkie, turn it up loud n pround!
Another great video. I love the sound of Fender harmonic tremolo.
Thanks, Mark. So do I :)
Hello Doug, it's been a while. What a classic beauty. Very hot and dry in the Sierras,
Thanks, John. The same here......generally around 108+
What an absolutely gorgeous Bandmaster..great find! Repairs minimal..original is King to me! Great vid Doug.
Thanks, Lynn :)
Oh, she is a real beauty and has the voice of a choir of angels 🥰
One day I will get something similar to replace my modern PCB amps with
Good description, Peter. I hope you do :)
That's one hot blonde! But that harmonic tremolo is just magnificent...probably the most watery and rich I've ever heard. Such a great production from start to finish on this one Doug. 👍
Wow, thank you, Dan. So glad you enjoyed it.
What a cool circuit! Sounds great! Thanks, Uncle Doug!
You are welcome, Mike. Our pleasure :)
thanks for the effort you put in to bringing us these videos
uncle doug, its pure genius, always leaves a big smile on
everyones face i`m sure! as captain ahab said to mr
starbuck,"let me look into a human eye "
Glad you like them, William. Thanks :)
Thanks uncle Doug, very interesting about bias settings. What a beautiful amp. Great video
Thanks, RJ.
5 UD Vídeos yo catch up to!!! Bring em beers! This fandom won’t let you down ever UD!!! Cheers
Wow.....thanks for your continued support, K.
That trem circuit sounds amazing! Thx for the video, great job.
Thanks, Danny. Glad you liked it :)
You do a super job repairing all these amps.😊
Thanks, User :)
I am subscribed. What a great amp he found Himself. This rebuild was another another learner for sure.
That's good to hear, Mr. CC. Thanks !!!
Those new caps really brought that tremolo circuit to life. Sounds great Doug!
Thanks, Raymond :)
I have a 1965 band master since 1991 and only replaced the 2 houtput Tubes for Mesa boogie and everyting else is original and still working perfect ;)
You're a lucky guy, E.
Great videos! , very helpful when I get this old fender's in for repair👍
Glad you mentioned the thing about plate dissipation. I have experienced the same thing that 70% isn't always right when I built a 200 watt bass amp for a couple years ago, using 4x kt88 at 650 volt plate voltage. I biased the amp at 70% plate dissipation.,everything looking good. Then I plugged in a dummy load and a signal generator and suddenly the kt88 starts to redplate at only 140 watts output! Aftar a long time fiddeling with the bias I ended up at 21% plate dissipation before I could run the amp at full power without red plating. The signal was looking beautiful on the scope, no crossover distortion even at 180 watts.. So my conclusion is that plate voltage and transformer impedance is the decisive factors when it comes to plate dissipation. But I am no expert, just learned by doing😊
Glad you like 'em, Havar.
sweet sounding amp. you make em really the best they can be every time.
Thanks so much, Malcolm. That really is our goal.
Running better then new. Thanks for the looks see, that’s one lucky fellow. You stay safe out there. Almost the weekend time for a gas & oil fix.
Yes, indeed, OG. You too :)
Thanks again Doug, enjoyed every minute.
That's great to hear, Lex :)
Excellent. Your videos have been an excellent guide for me while I have been learning about fender circuits. I have an old bassman head in quite a state, and I will be diving in to overhaul it this weekend. I don't think I would know nearly enough to do this safely or to a decent standard if it wasn't for channels like this.
Thanks, KM. Best of luck with your project.
@@UncleDoug just to let you know, an absolute success. Amp is repaired, in safe stable working order and just needs minor tweaks from this point. A complete recap, new heater wiring, new power screen and bias resistors, new plate resistors, some other replacement parts and reversal of poor shoddy previous work. Thanks again for your excellent resources, couldn't have done this myself without you!
Another masterful exposition, Uncle Doug. I love the math and that you use the data to drive your actions. Also, love the geekery inducing that Fender probably ran out of transformers, given the transition of this circuit to another. Rock and roll!
Thanks, Tim. According to several viewers the suppositions about transitional power transformers seems to be correct.
@@UncleDoug History to that level of detail should be preserved. I thank you, sir!
Another fantastic UD video! And i really like the way that guitar sounds with your speaker on the demo. Bravo sir!
Thanks so much, NYC, and bless you for rescuing those pups.
Great job Doug. Amp sounds amazing. I vote p-90s, but I'm a single coil guy on Thursdays, Saturdays, and Mondays. Thank you, sir. Cats are sounding good too. Really like the drone flights and the music.
Greetings, Jim. Thanks !! I agree the P-90's have a nice clarity. Glad you enjoyed the festivities :)
Wonderful video, such a thorough and detailed, very clear explanation of this remarkable piece of vintage tech... great stuff! Thanks for making this video!
You're quite welcome, Clyde. Glad you enjoyed it.
Hi Uncle Doug..
I have a ’63 Fender Bassman and it has a 125P7B/606309 . Thanks, Uncle Doug
I'll bet my guess was right about them being a transitional part, Fernando. Thanks !!
That is one nice amplifier Doug! The owner did very well on his selection! I saw video of the Beach Boys live and they were using a lot of blonde piggyback Fenders. Leo must've been in great delight seeing his amps being played on world wide television! Great Job and say Hello to them katz!!
Thanks so much, KC. Will do :)
Thank you for all the great videos. Hours of entertainment and great jokes!
You're welcome, Paul......glad you enjoyed them :)
The 125A6A on the output makes sense. The power transformer (to my eye on the video, I could be completely wrong), looks like it's a re-stamp of a 125P1B (another common Fender Power Transformer), i.e. it looks like the 1 was stamped over to a 7. Beautiful wiring. Amazing amp and video as always.
Thanks for your input and nice comments, Bert.
As an old Fender fan (76) I can say that the bandmaster was one of the amplifiers with the best sound at the time.in conjunction with a 15 "Lansing loudspeaker and aDynacord or Echolette echo device that was an absolute top soundthat I still have in my ear to this day, together with a Stratocaster, of course.
I believe you, FS. They are one of Leo's greatest :)
I'm heading out for my morning bike ride but this is number one viewing when I get back...
Have a safe ride, ID. See you later.
Just wonderful stuff Doug, as usual. The harmonic tremelo really is special.
Thanks twice, TP :)
Great video and amp; that's the best vibrato I've ever heard!
Thanks so much, Ed :)
Very nice amp. My 5F1 ended up sounding the best around 55%. Enjoyed the flight.
Thanks, Andrew. I really think that conservative is the way to go with tube bias.
@@UncleDoug I agree! For fixed bias amps I'll often bias them to 50-60% PD for guitar. For blues harmonica you can get away with being biased even colder... I have an amp I built ftom an old 1963 Linear L50 PA amp which now largely follows a 5F6-A schematic. It runs about 540V on the plates of the 6L6GC's but I have it biased around 20mA. For cathode bias I still prefer warmer bias settings.