@@amskatebc Thanks, HS. My wife seems to disagree.....based on the amount of nagging I receive on a daily basis. She actually expects me to do household tasks other than amp repair :)
One error noted: At 20:04 I meant to say 820 Ohms, not 680. Please don't let this egregious error discourage you from becoming a Patreon patron or PayPal contributor (see video description for links) :) :)
Uncle Doug I don’t know, that is a truly unforgivable error. It’s a shame you had to mess up those numbers, because I was really considering donating my life savings to you. I might just give it to a crummy library or something, now.
@@spikebebop9070 I'm not sure about the Polish girls, but once you've witnessed the awe and majesty of Anastasia (Russian, by the way), you will realize the appeal.
Uncle Doug , When I was 21 , I started in electronic school. The class went through 5 teachers in a month and a half! I WISH I had a teacher like you! Now at 68 , I have learned more from you than ANY OTHERS!!!. I also wondered where you were. Glad to have you AND the cats back.!
Wow ! Your wife can really paint. I liked both Marshall circuits. They definitely each had their own caracter. Now I will let you get back to making more signs to auction. 😀
Thanks so much for all of your fantastic work. In the tone stack, the 1986 slope resister is a 56k , the 1987 should be a 33k and you’ll find that it makes a difference (more gain). Also the preamp mixing point (2 470k’s ) does have the 500pf bypass for the bright channel on the 1987. Sorry to be so picky but having made many 20 watt versions of this circuit, I can see the scheme in my sleep . Thanks again for sharing.
Check out The Trainwreck Pages by the late Ken Fischer of the legendary Trainwreck amplifiers. His "Super Bass To Super Lead Conversion" is full of not normally found tips and tricks. Regards 🎸
I wish I could like your videos 100 times! You have one of the most informative channels on the whole web. I think that they both sounded great, but as you summarized, the 1987 sounded more appropriate for lead use. Thank you for sharing your knowledge.
Uncle, I've started a DIY tube amp project couple years ago and I had watched many of your classes, I put it aside for lack of money to buy parts, but I'm back to finish the project. I've been re-watching some lessons and learning as much as I can from your repair works. Your voice and calmness are really inspiring and encouraging. Thanks for the best YT channel there is. Cheers from Brazil.
It´s clear that old capacitors makes the amp sound more brighter, meanwhile the new ones sound more midrange and powerfull. Thanks Uncle Doug for being back! CHeers from Argentina!.
The original 1987 configuration is more sparkling and has cleaner overall sound quality. The mustard caps are speaking to me. Great video Doug and killer amp .
I'd almost say the 1986 is a bit "wooly" nearing muddy, being a bit too big in the bottom / low mids (it seems to cause the breakup to occur at the wrong frequency). The '87 has teat boosted/crisp upper mid that works great for guitar. I might say something completely different if Doug was playing a P-Bass, however....
The Lads at That Pedal Show have a re-issue 50 watt 1987x (the "x" indicates an effects loop is installed)'that sounds great though they frequently complain about a bright cap that needs to be changed evidently a common issue with the 1987.
The circuit was changed, particularly in the area of tone, as was pointed out in the video. To suggest it's due to the use of a specific type of component might be a stretch.
Sounds amazing. The 87 mod sounds the best in my opinion, although I very much doubt that it has to do with the mustard caps. I think you could have changed the values and use modern caps and had the same exact results.
First Happy New Year UD! Secondly I prefer the sound of the modern caps, IMHO they sound noticeably cleaner! Lastly kudos on the hotrod love all your upgrades!
Welcome back! And thanks for the great return video. Nice job on the Marshall. I like the sound of the 1987 conversion. The hot rod is going to look sharp with the triple carbs.
I firmly believe that nonsense about caps is completely in folks imagination. I’m not saying to use the cheap, great for radios, yellow Chinese ones, just a good quality Sprague or the newer orange drops or tubular Mallory.
Pete Dazer No... all caps have a slightly different sound. We can even measure the characteristics that cause these slight sonic variations with specialized testers built by Hewlett Packard originally back in the late 1970. It took 2 testers to cover a wide frequency range from a few Hz out to low radio frequency. At slightly over $10,000 each in the 1970s, few were sold outside of large business and standards labs. I now own both the HP units, can make all the measurements for DA, DF, ESR, and other characterizations.
Hi Pete I agree as far as how good our hearing is, as noted by Jennifer the caps are different but can we actually hear it. The mods that Doug did mostly the .1 to .022 is what has changed the sound in this amp.
The type is more important than the brand. Almost all film caps are appropriate for audio. Electrolytics are okay for large bypasses. Ceramics can be somewhat poor if they are high dielectric constant types because the capacitance varies with voltage. An exception to this is if the value is so high that little AC voltage is developed across them.
@@jenniferwhitewolf3784 DA, DF, ESR al have very little effect on sound in a well designed circuit. You can measure it, but you won't hear it. "Cap upgrades" are nothing but snake oil.
It takes time to build someone like uncle Doug ... time efforts and patience ! Priceless RUclips channel that deserves a special award (why are all RUclips awards always orientated on popularity and not on the quality of the tips provided ?) . Doug's the best out there ... period !. Cheers from a humble french tube enthousiast ;)
John Simms Yes the 1986 bass version sounds better then the 1987.It takes pedals better and are punchier.Malcolm Young,Gary Moore and Paul Kossof etc prefered the super bass amps.
You were sorely missed, dear Uncle. This conversion was the exact platform for your triumphant homecoming. Before diving into the particulars, I think it important to pay proper recognition to your conscientious regard to the ever present purists who are unfortunately poised to pounce on any modicum of opine assumptions. It is this type of wholehearted consideration that sets your channel apart from most amplifier technological sort. The audio test(s) were part and parcel of this entire conversion, The tonality on the 1986 circuit is overtly at the bottom of the frequency spectrum. It demonstrates the obvious tailoring for a bass, or baritone guitar. Conversely, the 1987 had rich, high mids, and an airy clarity while strumming the P90 loaded Jr. The presence sounded comfortably familiar. It breathed differently, and without the flubby burp of the 1986. I didn't want to forget mentioning the fantastic packing job for the Mustard caps. Sometimes the most inane materials are harbingers of the highest genius. I enjoyed this new seasons episode of Uncle Doug. Please keep `em coming! Thanks for sharing, and enjoy the weekend.
greetings from across the pond! Jack and Olly's playing is coming on in leaps and bounds! Especially considdering they have to change from a 7 1/4 fret radius to a 12". Good fun video & comensurate art work by your wife. Thanx Doug and all the best with your projects
It really is good to have you back, Doug. I also heard the differences, but I can’t decide whether the difference was due to the caps, or to the changes you did to convert the circuit from the 1986 to the 1987 circuit. But it does sound much better.
Great thanks for you Uncle Doug, and to your friend from the Netherlands for that experiment. Yes there is a big difference, as you explained, and as your friend’s preference of tones or taste of music.
So happy to watch your great videos again after a painfully long while! I just 4 days ago accidentally found and tested 70's NOS 400V mustard capasitors and I was very surprised because they did not leak at all. They were very tightly in tolerances as well so maybe I will test if they bring any mojo to sound. To be honest, I have made comparisons earlier several times and it is almost impossible for a normal person to tell if the cap is polystyrene, polycarbonate, polypropylene or paper if it does not leak and is within tolerance. For some reason I personally like old bright yellow Philips HQ polycarbonate caps. They never have failed and IMO sound great.
Thanks for this Vid Uncle Doug. Glad to see you back. Love your addition of your furry friends. Life, guitars, amps and hot rods are not the same without a friend to share them with.
U.D. You came dangerously close to starting WW3 by demoing the tonal differences in caps. Thankfully, your cap comparison WITH the addition of a circuit mod saved the day. BTW, that's a very nice '30 Ford. Seeing that SBC with the small distributor cap shot me back to the 70's when I would hover a hot engine to set the dwell. Glad you're back!
Hey Doug, you are they type of person that excited me to become and electrical engineer many years ago. Now I am a software engineer, but as I am sure you can understand that's because we all need to pay the bills. Keep going with these videos because you are inspiring a future generation. Make America great again! (even though I am Australian)
Hey Mark 👋 I know this was 4 years ago but may I ask what sort of software it is that you work with? Have you ever done any PLC work by chance? Just curious
Very glad to see you back with another terrific video. There are some subtle variations in Marshall amps and where some of the components are can cause unexpected changes to the sound. That 500pF cap across the 470K resistor I think is actually in both the 1986 and 1987 models and it has what I think is an unwanted effect. In both amps it is connected between the grid of V2a and the wiper of the lower channel (schematic position) Volume control. If you are playing through the upper channel (schematic position) and you alter the lower channel Volume control it acts like a simple treble cut tone control. I realise 500pF is not a large value cap for a treble cut control but it does have an effect. Conversely it boosts the treble of the lower channel by routing the higher frequencies around the 470K resistor, plus the 1987 lower channel has a 0.005uF 'bright' cap across its Volume control. The Bluesbreaker has a 220pF across a 470k and the JTM45 has a 500pF across a 220K. I only found this out about a year ago when repairing the aforementioned amps. I guess if the player is aware of the effect it doesn't matter but I still think to have one channel's Volume control effect the tone, albeit slight, of the other channel is a bit odd. But it's still a Marshall so who am I to criticise. As a teenager back in the sixties those mustard caps were in open trays all laid out on tables in the parts store I frequented. I think I need a TARDIS. All the best for the New Year. Jeff.
Great video Uncle Doug. Good to see you back on the Tube. My Yorkie really perked up her ears when you played the Mustard version 1987 at the end of video.
Hi Doug nice resto job on the amp. Interestingly these valve rectified 50 watt heads were essentially JTM 45 circuit running EL 34 output as opposed to the earlier KT 66 / 6l6 type with the output transformer matched to the EL 34`s. The split cathode circuit came out in `68. The bass circuit is closest to the original layout.
it really is a Happy NewYear now!!!! we were all very worried but very satisfied now that you are back and well ,I honestly in some songs liked the 1986 ,your wife is very talented love the painting ,Very nice work on the Hot Rod!!!
Thanks Uncle Doug!! That was an amazing journey through those two Marshalls(I know it was the same amp).. I understand now why guitar players love the 1986 for guitar.. I actually prefer it as a rhythm player..and the 1987 which I owned at one time for a lead player.. mine was a made in 74’ JMP 50 lead .. thanks again and welcome back!! Also thanks to Jack and Ollie!!
Really good to have you back. was woundring. My two cents I liked the 1986. your graficts spectacular should bring a pretty penny. And your wife's painting very nice. she's a talented lady. Must run in the family. As always thank you for your time.
Wondered where you had been great to have you back, WOW the difference is night and day I really like the model 1987 with the Mustard Caps sound for the guitar, when compared back to back like that you can really tell that the 1986 is a bass amp.
Another great video uncle Doug - really missed your presence so it’s great to have you back. Those cats have obviously been using their time wisely and their playing is getting better and better!!. It’s great to see a REAL animal lover like you - my wife and I both have the view that if someone does not like animals, they are usually not the sort of person we wish to be associated with. Take care and please try to keep the videos coming. Thanks for being so kind in passing on your wealth of knowledge.
The differences are relatively minor, but definitely audible. The 86 had a little more bass end, and the 87 had more focused mids. Maybe it's just placebo, but I preferred the tone of the 87. Sounded more like a Marshall to my ears while the 86 seemed to have had a little bit of Fender sprinkled in there. Odd I know, but thats what I heard. I am so "electronics challenged" that Ive been banned from purchasing a soldering iron, but I always watch your vids through my ignorant bliss. I find them fascinating. Thanks very much for keeping me entertained.
This in my opinion is one of your best videos. Yes I am a Marshall enthusiast and believe the 1987, 1959, 2203 and 2204 are the best amp circuits ever developed. An excellent comparison between shared and split cathode at V1.
Have a sis in Tennessee and other family in Kentucky. Deep off the highways, still lots of cars down there. Going to start dragging them up north, drive them for a bit, then flip ‘em!
Greetings Uncle Doug, I sure am glad you posted another video, I was gettin' kinda worried Even though I am not a musician and so will never need a guitar amp I really enjoy your videos and have learned a lot about tube amplifiers from your videos. If you ever do a series about building a stereo hi fi amp I will build it. I also enjoy your Hot Rod stuff even though I have never owned one and probably never will. Nevertheless I really like looking at fine craftsmanship and who doesn't like a hot rodded engine? As a precision machinist with 40 some years experience the mechanical stuff is quite appealing. Finally, it warms my heart to see the affection and care you show your pets. Rusty sure was special and Jack and Ollie are too. Thanks for posting your videos. Cheers, Eric
Thanks so much for all your very nice comments, Eric. My grandfather was a master machinist at the L.S. Starrett Company for many, many years. I was fortunate to inherit some of his tools and tool cabinet.
@@UncleDoug I too was fortunate to obtain many L.S. Starrett gauges meters jigs and various other layout tools when I was younger.. I often wonder how they ever made any money, as their tools seem to never break! I also have to figure out who I'm going to will them to!!!
What a difference in Sound after the Modifikation. It Sounds much warmer to my ears. This is a good example that capacitors are frequency orientated components of the curicut. Greetings from Germany.
Uncle Doug Marshall is my favorite amplification and I've used it with my bass in the beginning mainly playing Gibson's through it, but now through modern technology able to put anything through it for many many years . I have a 1970 Marshall Major the Good ol 200w yes 4 kt88's the amplifier doesn't get used out no more and I've owned it since 1978 and I started playing bass and 76 this amplifier has never ever let me down and now I have been searching the roads for the JMP 50 thanks for posting this video 💜
@@UncleDoug Marshalls are tricky but I just love watching what you do, I really wish I had some time or maybe you will find some time to come up when I'm looking for in a preamp I got time once again you rock dude you rock 💜
Well, indeed it's been a long while since we last heard from you and were privileged to witness the mastery of your electronic diagnosis/repair component function/quality/history, soldering & cable mngt prowess! Whew! And all for FREE! Cat lover, too! ;-) White paint spots on Tolex or leather often covered, too!
Doug you can use 018 Mullards/Bianchi's much cheaper than the insane price of 022's without any noticeable loss. Shared Cathode on V1 Vs Split cathode can help with gain also. The change in tone stack to lead spec and the .68 on V2 will increase mid gain also. You can go to a 25k pot 4.7k R .68 combo instead of 5k pot 01 combo on the negative F.B. loop for a less bright more mid presence control and reduce problems with a scratchy presence control. Try a 50K instead of a 22k pot on the mid control for more lower mids. Also where you put the negative F.B. lead on the impedance selector can change the gain of the amp in a good way. Marshall made numerous subtle changes over the years and everything that I have mentioned minus the use of 018's can be found in different models over the years and the total combination sounds great in a 50 watt.
@@UncleDoug Well it was unsolicited but life is all about sharing so I thank you for being so cordial. By the way I have a bunch of mustards Radio spares and lemcos if you ever need a source. Health issues forcd me from the repair business a few years back and I am sitting on a pile of parts for fender and marshall. Have a good one.
@@UncleDoug Doug a nice mod for Fender amps with vibrato which is completely reversible is to replace the ra pot on the vibrato with a switched spst type of the same value in order to remove the vibrato from the circuit and gain up the amp by about 25% works great on deluxe reverb amps makes them break up sooner for more grit also makes a twin reverb break up some a lot sooner. Lots of blues players love that mod :)
@@UncleDoug I thought both amps were similar in sound. If both amps were in big tubes. One amp in each tube I would say the first one was recessed a foot in campared to the second amp sitting right at the entrance of it's tube. Other wise I couldn't hear any difference in the tone, high or lows, anything of both the amps.
Thank you Uncle Doug, you really had a lot of work in this video to prepare the Model 1986-Marshall into a 1987-one ! What a great job. Thanks also to Jack and Olli for doing the Audio-Test. For my opinion the 1986-version is favorite, but as always in liking, you hardly can argue. But I do think that the difference comes from circuit, not from NOS-mustards. But all this seems nothing against the sound that will come out of the exhausters of your V8- 350cui-Chevi-Engine ! :))
Thanks for the new video, it's awesome! I agree with most of the other commentors, the 87' version certainly has tighter bottem end and nicer top end, it's hard to pick which one sounds better, they're both great!
Uncle Doug one of the Worlds, the worlds let me rephrase my statement please the world's number one top electrical engineer of any amplifier that ever Sayang to an audience, this is your favorite nephew the one where we couldn't quite fit that Mesa boogie in, nevertheless good to hear Ya Unck, you're still at the top and at the helm God bless take care watching everyone I can.
The difference wasn't really that apparent to me until your cats played Interstate Lovesong. That single note part, the notes really leapt out. Very nice and a very successful conversion and a very informative video for me! Hopefully I'll be being loaned a 100 watt Plexi soon that needs a bit of love apparently it has two EL34s removed and is also 'running hot' sounds like fun! I also don't know if an MV or non MV amp yet I've asked for pics. Hopefully it's not been too buggered around with
I finally finished this saga and bang... Interstate Love Song! I grew up in the grunge era, and not even people my age that followed the grunge bands know this song, at least in my country. Lesson of the day: always keep up with good music.
Agreed. Major difference and it will scream as a lead with a little personal adjustment to the users likes when playing precision lead riffs. What a difference! If his other amp sounds the same as the 86' flavor than he's got the best of both worlds. Great Job and nice to see you again in addition to Cassy supervising your every move. :) She's become a little furball who's taken to domestication well and gotten healthy looking! She's a daddies girl, that's for sure! I really like the new setup on the RatRod. Those carbs on the distributor are going to look sweet! The ports should be cake. They can be done be hand with a cheat block for tapping (for perpendicularity & proper depth), You're only dealing with aluminum (butter). Can't wait for the next installment and welcome back, we missed you!!!
@@UncleDoug The felling is mutual my friend! The RatRod is really coming along nice! Can't wait to see it finish and hear you foot making sure the accelerator is still working properly! ;)
@@ThePreyMantas I finished installing roll-up windows in the doors today.....what a job !! When they chopped the top, they massacred the doors and window channels. I got dark-tinted glass for the "gangster" look :)
Thanks the lord! Uncle Doug is posting a video. This is probably saving my complete week! I'll save that for later that evening, sitting on my couch with my dogs, while my wife is at work, eating a lot of stuff, I shouldn't eat and just relax.👏👏👏
Noticeable difference as expected in the bass range. I have noticed as I get older that I lean more towards the low mid to bass range and shy away from the ear stinging high pitch tones. This amp sounds great either way but me personally I would probably shoot for somewhere in the middle of these two circuits. Great video as always!
Hi Uncle Doug & Kitties, I hope you had a nice break, good to see you again. I noticed a difference between the 1986 & the 1987 Mustard cap circuit. The 1987 was cleaner sounding, brighter. Was that some Stone Temple Pilots I detected?, & some Joe Walsh. I won tickets to see Warren Zevon, Werewolves of London song, and Joe Walsh came in and did a few songs with Warren, this was in Seattle, Wa., '90's. Be a sad day when you finally call it quits. I have learned so much, Thank you for sharing your knowledge and experience, your a great teacher. Good guitar work by the way. You and your wife are both talented. Till next time, all the best, C.
So great to see you back Doug. I listened to the sound clips with my eyes closed and wrote down which one I liked better. To my surprise I liked the 1986 with modern caps in the majority of the clips. The 1987 Mustard had more *sparkle* but to my ears less gain. Good video great job.
I to am very glad to see "Good 'Ol Uncle Doug"! The difference was very apparent between the two circuits. The '86 was more bassy, especially on those flappy low notes. The increased treble and mid were audible but the overall tone was similar. It's a Marshall for Gods sake. It was starting to break up a little early to give the "British Sound". The EL34s sounded like they should. Clapton would be proud! Guitars and cars, what a combination. So many similarities, paint, loud sounds and the most important.....they attract beautiful women! You can beat an egg, you can beat a drum, but you can't beat a Hot Rod! Thanxz
Great video, UD! I believe the Marshall conversion was a complete success. The difference in tone between the two configurations was like night and day. Great playing by your friends, especially song #4 - love me some Funk 49. Nice work on the 350. Pertronics makes some good fully electronic replacements for older distributors. I'm guessing an intake manifold for three deuces is hard to come by or ridiculously expensive - I haven't been looking for one so I don't really know. Nice work all around.
Wow ! This is just what I wanted to see, I had my 1986 converted to a 1987, and by far, it sounds more suitable for my guitar, and now I blend the 2 channels to suit which has been prepatched internally, I noticed this has a tube rectifier in the same year 1968 they did change over to a solid-state rectify. Excellent video UD, I will share this with my tech guy......✌🏻
Great video as usual. I have every confidence that the sound difference was due exclusively to the difference in the circuits and had nothing to do with the NOS caps. Regardless I enjoyed it very much, it's always a pleasure watching you guide us from the schematics to the physical implementation.
Uncle Doug, one of the greatest human beings in the world.
Wow......thanks so much, Joe.
Joe He can adopt me anytime.
Agreed. Just the sound of Uncle Doug's voice reduces my anxiety. So now I just consider this, "Tube amp therapy with Uncle Doug." :)
@@amskatebc Thanks, HS. My wife seems to disagree.....based on the amount of nagging I receive on a daily basis. She actually expects me to do household tasks other than amp repair :)
tardiff?
thanks the gods you are back i was worried after such a long radio silence. now to watch the video.
Thanks. I hope you enjoy it, Mr.G.
You said exactly what I wanted to say! I appreciate that. Thanks.
Long awaited :-)
"Ditto" yesterday I posted a comment on the last video (U.D. Responded) just to, pardon the cop speak, "check welfare"
@@UncleDoug Hey uncle doug, do you ever do custom guitar amp mods? or be willing to try it?
One error noted: At 20:04 I meant to say 820 Ohms, not 680. Please don't let this egregious error discourage you from becoming a Patreon patron or PayPal contributor (see video description for links) :) :)
Uncle Doug I don’t know, that is a truly unforgivable error. It’s a shame you had to mess up those numbers, because I was really considering donating my life savings to you. I might just give it to a crummy library or something, now.
@@8BitBrody Darn, 8 Bit. That's what I get for being honest. At least give your millions to animal rescue.....or a home for aging pole dancers ;)
@@UncleDoug I don't know what the deal is. Why is everyone so concerned about Polish dancers?
@@spikebebop9070 I'm not sure about the Polish girls, but once you've witnessed the awe and majesty of Anastasia (Russian, by the way), you will realize the appeal.
The Marshall 1986 JMP-50 Bass Amp was the preferred model of 'Free' guitarist Paul Kossoff.
Uncle Doug , When I was 21 , I started in electronic school. The class went through 5 teachers in a month and a half! I WISH I had a teacher like you! Now at 68 , I have learned more from you than ANY OTHERS!!!. I also wondered where you were. Glad to have you AND the cats back.!
Thanks so much, Wayne. It's good to be back.
Wow ! Your wife can really paint. I liked both Marshall circuits. They definitely each had their own caracter. Now I will let you get back to making more signs to auction. 😀
Thanks three times, Jason :)
Thanks so much for all of your fantastic work. In the tone stack, the 1986 slope resister is a 56k , the 1987 should be a 33k and you’ll find that it makes a difference (more gain). Also the preamp mixing point (2 470k’s ) does have the 500pf bypass for the bright channel on the 1987. Sorry to be so picky but having made many 20 watt versions of this circuit, I can see the scheme in my sleep .
Thanks again for sharing.
Thanks for your very knowledgeable input, Bill. I checked and you're correct.
Check out The Trainwreck Pages by the late Ken Fischer of the legendary Trainwreck amplifiers.
His "Super Bass To Super Lead Conversion" is full of not normally found tips and tricks.
Regards 🎸
the teach is back! thank gods! (jack and cassie too)
It's good to be back, Rocko :)
You're a great tech AND a great instructor, Unc. Thank you!
Thanks twice, Randy.
I wish I could like your videos 100 times! You have one of the most informative channels on the whole web. I think that they both sounded great, but as you summarized, the 1987 sounded more appropriate for lead use. Thank you for sharing your knowledge.
You're welcome, M16. Thanks for your nice comments.
Uncle Doug... love your content ... thanks for inviting us along ❤
Thanks for joining us, Dave :)
Both versions sound great! Welcome back, have a great 2020!
Thanks, Peter. You too :)
Uncle, I've started a DIY tube amp project couple years ago and I had watched many of your classes, I put it aside for lack of money to buy parts, but I'm back to finish the project. I've been re-watching some lessons and learning as much as I can from your repair works. Your voice and calmness are really inspiring and encouraging. Thanks for the best YT channel there is. Cheers from Brazil.
You're quite welcome, HV. We're glad the videos are helpful and wish you the very best with your project.
Beautiful sounding amp either way. Thanks for posting Doug.
Thanks, K41 :)
It´s clear that old capacitors makes the amp sound more brighter, meanwhile the new ones sound more midrange and powerfull. Thanks Uncle Doug for being back! CHeers from Argentina!.
Thanks for your input, Fernando.
The original 1987 configuration is more sparkling and has cleaner overall sound quality. The mustard caps are speaking to me. Great video Doug and killer amp .
Thanks, Gonzo. I agree with your assessment.
Agreed. The 86 would be good for a rhythm player and the 87 for a lead player.
I'd almost say the 1986 is a bit "wooly" nearing muddy, being a bit too big in the bottom / low mids (it seems to cause the breakup to occur at the wrong frequency). The '87 has teat boosted/crisp upper mid that works great for guitar.
I might say something completely different if Doug was playing a P-Bass, however....
The Lads at That Pedal Show have a re-issue 50 watt 1987x (the "x" indicates an effects loop is installed)'that sounds great though they frequently complain about a bright cap that needs to be changed evidently a common issue with the 1987.
The circuit was changed, particularly in the area of tone, as was pointed out in the video. To suggest it's due to the use of a specific type of component might be a stretch.
The tone ended up sounding chrisp and clear. Nice work
Wow uncle doug is back..we all love you uncle dough.❤
The feeling is mutual, John.
Had been wondering about you. Thanks for keeping the channel going, boss man. Some of the best stuff on the net.
Thanks, MF. We appreciate your concern. Everything is going well.....glad to say.
Definitely cleaner with the mustard caps; "nicely done".
Thanks, John :)
Marshall, we are clean. That's the advertising they had back then? I didn't know.
Just messin'.
@@therugburnz They definitely are clean.....and loud :)
Always love absorbing an Uncle Doug video - your enthusiasm for knowledge & getting results is always inspiring.
Thanks, Spud. You're always welcome :)
Sounds amazing. The 87 mod sounds the best in my opinion, although I very much doubt that it has to do with the mustard caps. I think you could have changed the values and use modern caps and had the same exact results.
Thanks, G & G. Don't tell anyone......but I agree with you ;)
Superb as always, Uncle Doug! Thanks for passing on your knowledge!
Thanks. You're welcome, Bryan.
First Happy New Year UD! Secondly I prefer the sound of the modern caps, IMHO they sound noticeably cleaner! Lastly kudos on the hotrod love all your upgrades!
+1 on the hot rod. the 3x 2 barrel carb (6-pack!!) is such a classic.
Welcome back! And thanks for the great return video. Nice job on the Marshall. I like the sound of the 1987 conversion. The hot rod is going to look sharp with the triple carbs.
Thanks..... It's good to be back.
I firmly believe that nonsense about caps is completely in folks imagination. I’m not saying to use the cheap, great for radios, yellow Chinese ones, just a good quality Sprague or the newer orange drops or tubular Mallory.
Pete Dazer No... all caps have a slightly different sound. We can even measure the characteristics that cause these slight sonic variations with specialized testers built by Hewlett Packard originally back in the late 1970. It took 2 testers to cover a wide frequency range from a few Hz out to low radio frequency. At slightly over $10,000 each in the 1970s, few were sold outside of large business and standards labs. I now own both the HP units, can make all the measurements for DA, DF, ESR, and other characterizations.
Hi Pete I agree as far as how good our hearing is, as noted by Jennifer the caps are different but can we actually hear it. The mods that Doug did mostly the .1 to .022 is what has changed the sound in this amp.
The type is more important than the brand. Almost all film caps are appropriate for audio. Electrolytics are okay for large bypasses. Ceramics can be somewhat poor if they are high dielectric constant types because the capacitance varies with voltage. An exception to this is if the value is so high that little AC voltage is developed across them.
@@jenniferwhitewolf3784 DA, DF, ESR al have very little effect on sound in a well designed circuit. You can measure it, but you won't hear it. "Cap upgrades" are nothing but snake oil.
Mister Hat for the most part I agree. A good quality cap compared to another of equal quality and value will not sound any different.
It takes time to build someone like uncle Doug ... time efforts and patience ! Priceless RUclips channel that deserves a special award (why are all RUclips awards always orientated on popularity and not on the quality of the tips provided ?) . Doug's the best out there ... period !. Cheers from a humble french tube enthousiast ;)
Wow, thanks so much for your very nice comments, Nicolas. We really appreciate them.....and you :)
It sort of sounded like the the 1986 version was a little more punchier.
John Simms Yes the 1986 bass version sounds better then the 1987.It takes pedals better and are punchier.Malcolm Young,Gary Moore and Paul Kossof etc prefered the super bass amps.
Great comparison , and you can really hear the difference. Looks like the Coup is coming along nicely. Good to see you back!
Thanks, James. It's good to be back.
You really had me worried by the long hiatus. Very happy to see you back.
Steve
My old granny used to say, "The only good hiatus is a long hiatus" :) Thanks, Stephen.
Ohhhh, YES! The mustard caps machine!
(Great to know that Jack & KC are weathering this isolation well.)
Thanks, Dave. They are indoor kitties, pampered to the max.
Really glad to see you back. You are still my favorite RUclips videos. Hope to see more. Thanks Uncle Doug!
You're welcome, Robert :)
What a difference in amp and car, great to have you back.
Thanks, Mr. B.
You were sorely missed, dear Uncle. This conversion was the exact platform for your triumphant homecoming. Before diving into the particulars, I think it important to pay proper recognition to your conscientious regard to the ever present purists who are unfortunately poised to pounce on any modicum of opine assumptions. It is this type of wholehearted consideration that sets your channel apart from most amplifier technological sort. The audio test(s) were part and parcel of this entire conversion, The tonality on the 1986 circuit is overtly at the bottom of the frequency spectrum. It demonstrates the obvious tailoring for a bass, or baritone guitar. Conversely, the 1987 had rich, high mids, and an airy clarity while strumming the P90 loaded Jr. The presence sounded comfortably familiar. It breathed differently, and without the flubby burp of the 1986. I didn't want to forget mentioning the fantastic packing job for the Mustard caps. Sometimes the most inane materials are harbingers of the highest genius. I enjoyed this new seasons episode of Uncle Doug. Please keep `em coming! Thanks for sharing, and enjoy the weekend.
Thanks so much, Alex, for your very thoughtful analysis and nice comments.
@@UncleDoug Anytime! I relish the compliment.
greetings from across the pond! Jack and Olly's playing is coming on in leaps and bounds! Especially considdering they have to change from a 7 1/4 fret radius to a 12". Good fun video & comensurate art work by your wife. Thanx Doug and all the best with your projects
Thanks so much, Phil.....from all of us :)
It really is good to have you back, Doug. I also heard the differences, but I can’t decide whether the difference was due to the caps, or to the changes you did to convert the circuit from the 1986 to the 1987 circuit. But it does sound much better.
Thanks, Bill. Probably a combination of both.
Great thanks for you Uncle Doug, and to your friend from the Netherlands for that experiment. Yes there is a big difference, as you explained, and as your friend’s preference of tones or taste of music.
You are quite welcome, Omar.....from all of us.
So happy to watch your great videos again after a painfully long while!
I just 4 days ago accidentally found and tested 70's NOS 400V mustard capasitors and I was very surprised because they did not leak at all. They were very tightly in tolerances as well so maybe I will test if they bring any mojo to sound.
To be honest, I have made comparisons earlier several times and it is almost impossible for a normal person to tell if the cap is polystyrene, polycarbonate, polypropylene or paper if it does not leak and is within tolerance.
For some reason I personally like old bright yellow Philips HQ polycarbonate caps. They never have failed and IMO sound great.
Thanks, J. I agree that different types of capacitors rarely have an audible effect.
Thanks for this Vid Uncle Doug. Glad to see you back. Love your addition of your furry friends. Life, guitars, amps and hot rods are not the same without a friend to share them with.
Amen, Peter, and I would like to think that our international "family" consists of about 75K friends we can share with.
U.D. You came dangerously close to starting WW3 by demoing the tonal differences in caps. Thankfully, your cap comparison WITH the addition of a circuit mod saved the day.
BTW, that's a very nice '30 Ford. Seeing that SBC with the small distributor cap shot me back to the 70's when I would hover a hot engine to set the dwell.
Glad you're back!
Thanks, Randy. Yes, indeed. Fond memories of setting the points with a matchbook cover as a feeler gauge......in the dark.
Hey Doug, you are they type of person that excited me to become and electrical engineer many years ago. Now I am a software engineer, but as I am sure you can understand that's because we all need to pay the bills. Keep going with these videos because you are inspiring a future generation. Make America great again! (even though I am Australian)
Thanks so much, Mark. We're doing our best ;)
Hey Mark 👋 I know this was 4 years ago but may I ask what sort of software it is that you work with? Have you ever done any PLC work by chance? Just curious
@@michaelknight4041 Quite a few languages over the years. Yes, including PLC (TwinCAT). Im a .NET dev now, or should I say Prompt Engineer 😉
Very glad to see you back with another terrific video. There are some subtle variations in Marshall amps and where some of the components are can cause unexpected changes to the sound. That 500pF cap across the 470K resistor I think is actually in both the 1986 and 1987 models and it has what I think is an unwanted effect. In both amps it is connected between the grid of V2a and the wiper of the lower channel (schematic position) Volume control. If you are playing through the upper channel (schematic position) and you alter the lower channel Volume control it acts like a simple treble cut tone control. I realise 500pF is not a large value cap for a treble cut control but it does have an effect. Conversely it boosts the treble of the lower channel by routing the higher frequencies around the 470K resistor, plus the 1987 lower channel has a 0.005uF 'bright' cap across its Volume control. The Bluesbreaker has a 220pF across a 470k and the JTM45 has a 500pF across a 220K. I only found this out about a year ago when repairing the aforementioned amps. I guess if the player is aware of the effect it doesn't matter but I still think to have one channel's Volume control effect the tone, albeit slight, of the other channel is a bit odd. But it's still a Marshall so who am I to criticise. As a teenager back in the sixties those mustard caps were in open trays all laid out on tables in the parts store I frequented. I think I need a TARDIS.
All the best for the New Year. Jeff.
Thanks for your very detailed and knowledgeable input, Jeff.
I'm glad to see new episodes . I missed you and was not the only one as i can see in the comments.. Best wishes for 2020.
Thanks, Ant. Likewise on the good wishes :)
People are very lucky, that you share your knowledge and expert know how, in an easy to understand way.
We're lucky to have appreciative viewers like you, Polly.
Hi Uncle Doug, my vote is for the 1987 mustard cap version. Thanks for all the great videos. You’re an awesome teacher.
Thanks for your input and nice comments, Randy.
Great video Uncle Doug. Good to see you back on the Tube. My Yorkie really perked up her ears when you played the Mustard version 1987 at the end of video.
Yorkies are noted for their discriminating taste, Curtis :)
@@UncleDoug Affirmative,She likes my wife a whole lot more than I.Correctly I might add.
Glad you're back, Uncle Doug! I've been jonesing for another video showcasing your awesome skills.
Thanks so much, GMG. It's good to be back.
Beautiful work, the update sounds much better to me. Very nice cactus flowers painting. The hot rod looks good so far.
Thanks, Andrew :)
Hi Doug nice resto job on the amp. Interestingly these valve rectified 50 watt heads were essentially JTM 45 circuit running EL 34 output as opposed to the earlier KT 66 / 6l6 type with the output transformer matched to the EL 34`s. The split cathode circuit came out in `68. The bass circuit is closest to the original layout.
Thanks so much for this information, Brian. We are learning a great deal about this unusual circuit from our very knowledgeable and helpful viewers.
Uncle Doug you are a RUclips treasure! These videos are amazing!
Wow, thanks, Stephen.
it really is a Happy NewYear now!!!! we were all very worried but very satisfied now that you are back and well ,I honestly in some songs liked the 1986 ,your wife is very talented love the painting ,Very nice work on the Hot Rod!!!
Thanks several times, Joe :)
Thanks Uncle Doug!! That was an amazing journey through those two Marshalls(I know it was the same amp).. I understand now why guitar players love the 1986 for guitar.. I actually prefer it as a rhythm player..and the 1987 which I owned at one time for a lead player.. mine was a made in 74’ JMP 50 lead .. thanks again and welcome back!! Also thanks to Jack and Ollie!!
You're quite welcome, Luth. Thanks so much.
Really good to have you back. was woundring. My two cents I liked the 1986. your graficts spectacular should bring a pretty penny. And your wife's painting very nice. she's a talented lady. Must run in the family. As always thank you for your time.
It was our pleasure, DH. Thanks for your nice comments.
Glad you're back!...and the mustards sound better imho...and I'm anxious to see the 3 carbs in action!
Thanks, Greg. Stay tuned :)
Very happy you are back Uncle Doug. Bless you for sharing your wisdom with us!!!
Thanks, F1.
Wondered where you had been great to have you back, WOW the difference is night and day I really like the model 1987 with the Mustard Caps sound for the guitar, when compared back to back like that you can really tell that the 1986 is a bass amp.
Thanks for your input, CMD.......great screen name :)
Another great video uncle Doug - really missed your presence so it’s great to have you back. Those cats have obviously been using their time wisely and their playing is getting better and better!!. It’s great to see a REAL animal lover like you - my wife and I both have the view that if someone does not like animals, they are usually not the sort of person we wish to be associated with. Take care and please try to keep the videos coming. Thanks for being so kind in passing on your wealth of knowledge.
Thanks for all your very nice comments, Robin.
So glad to see an Uncle Doug video! Pleased that you're okay too. Was getting worried. Thanks for the best content on here. TJ
Thanks, RD :)
Your wife's paintings are exquisitr! Clearly you are not the only one in the family with an excess of talent!
Thanks so much, Frank.......from both of us :)
The differences are relatively minor, but definitely audible.
The 86 had a little more bass end, and the 87 had more focused mids. Maybe it's just placebo, but I preferred the tone of the 87. Sounded more like a Marshall to my ears while the 86 seemed to have had a little bit of Fender sprinkled in there. Odd I know, but thats what I heard.
I am so "electronics challenged" that Ive been banned from purchasing a soldering iron, but I always watch your vids through my ignorant bliss. I find them fascinating. Thanks very much for keeping me entertained.
You're quite welcome, IP. Thanks for your input.
Glad you are back buddy. Congrats and looking forward to some new stuff. Thanks.
Thanks, Eric. It's good to be back.
This in my opinion is one of your best videos. Yes I am a Marshall enthusiast and believe the 1987, 1959, 2203 and 2204 are the best amp circuits ever developed. An excellent comparison between shared and split cathode at V1.
Thanks so much, Sting. We appreciate your comments.
Wow! Night and day uncle Doug. I'd be very happy with either one, but the Mustard Caps did it for me. Thanks for sharing.
You're welcome, CB :)
Such a blessing to have a creative & talented family!! Happy New Year, Unc!!!
Thanks so much, Abe. Likewise to you and yours.
Glad to see a new video from my favorite channel. Hope all is well
Never better, Jay. Thanks !!!
Wooooo glad ur back!! 1987 circuit for sure. Retiring April 1, now I can start playing around with cars again!
Thanks, 6. You're going to LOVE it !!
Have a sis in Tennessee and other family in Kentucky. Deep off the highways, still lots of cars down there. Going to start dragging them up north, drive them for a bit, then flip ‘em!
Greetings Uncle Doug,
I sure am glad you posted another video, I was gettin' kinda worried
Even though I am not a musician and so will never need a guitar amp I really enjoy your videos and have learned a lot about tube amplifiers from your videos. If you ever do a series about building a stereo hi fi amp I will build it.
I also enjoy your Hot Rod stuff even though I have never owned one and probably never will. Nevertheless I really like looking at fine craftsmanship and who doesn't like a hot rodded engine? As a precision machinist with 40 some years experience the mechanical stuff is quite appealing.
Finally, it warms my heart to see the affection and care you show your pets. Rusty sure was special and Jack and Ollie are too. Thanks for posting your videos.
Cheers,
Eric
Thanks so much for all your very nice comments, Eric. My grandfather was a master machinist at the L.S. Starrett Company for many, many years. I was fortunate to inherit some of his tools and tool cabinet.
@@UncleDoug I too was fortunate to obtain many L.S. Starrett gauges meters jigs and various other layout tools when I was younger.. I often wonder how they ever made any money, as their tools seem to never break! I also have to figure out who I'm going to will them to!!!
Yeah man. Again, a great video. I admire your dedication and even more so, your methodical discussion. Old skool is real skool.
Thanks so much, Markus :)
What a difference in Sound after the Modifikation. It Sounds much warmer to my ears. This is a good example
that capacitors are frequency orientated components of the curicut. Greetings from Germany.
Thanks, Roland. I agree :)
I like the 1986 circuit sound a bit more. Thanks for the video Doug!
You bet, Jim.
Uncle Doug Marshall is my favorite amplification and I've used it with my bass in the beginning mainly playing Gibson's through it, but now through modern technology able to put anything through it for many many years . I have a 1970 Marshall Major the Good ol 200w yes 4 kt88's the amplifier doesn't get used out no more and I've owned it since 1978 and I started playing bass and 76 this amplifier has never ever let me down and now I have been searching the roads for the JMP 50 thanks for posting this video 💜
You're welcome, Charles......glad you enjoyed it.
@@UncleDoug Marshalls are tricky but I just love watching what you do, I really wish I had some time or maybe you will find some time to come up when I'm looking for in a preamp I got time once again you rock dude you rock 💜
@@charleslambiase5670 Thanks, Charles :)
YES!!! The man is back in town! Great to hear your soothing tone again :) WB @UncleDoug .
Thanks, LB. It's good to be back.
Well, indeed it's been a long while since we last heard from you and were privileged to witness the mastery of your electronic diagnosis/repair component function/quality/history, soldering & cable mngt prowess! Whew! And all for FREE! Cat lover, too! ;-) White paint spots on Tolex or leather often covered, too!
We hope you enjoyed our recent efforts, Bob. Thanks !!!
Doug you can use 018 Mullards/Bianchi's much cheaper than the insane price of 022's without any noticeable loss. Shared Cathode on V1 Vs Split cathode can help with gain also. The change in tone stack to lead spec and the .68 on V2 will increase mid gain also. You can go to a 25k pot 4.7k R .68 combo instead of 5k pot 01 combo on the negative F.B. loop for a less bright more mid presence control and reduce problems with a scratchy presence control. Try a 50K instead of a 22k pot on the mid control for more lower mids. Also where you put the negative F.B. lead on the impedance selector can change the gain of the amp in a good way. Marshall made numerous subtle changes over the years and everything that I have mentioned minus the use of 018's can be found in different models over the years and the total combination sounds great in a 50 watt.
Thanks so much for your very knowledgeable input, Sam.
@@UncleDoug Well it was unsolicited but life is all about sharing so I thank you for being so cordial. By the way I have a bunch of mustards Radio spares and lemcos if you ever need a source. Health issues forcd me from the repair business a few years back and I am sitting on a pile of parts for fender and marshall. Have a good one.
@@sambekins I work on all sorts of Fender amps, so I may avail myself of your offer, Sam.
@@UncleDoug Doug a nice mod for Fender amps with vibrato which is completely reversible is to replace the ra pot on the vibrato with a switched spst type of the same value in order to remove the vibrato from the circuit and gain up the amp by about 25% works great on deluxe reverb amps makes them break up sooner for more grit also makes a twin reverb break up some a lot sooner. Lots of blues players love that mod :)
Your Okay. Been asking all over about you. Nice amp(s). Nice guitar. Nice car. Glad your back!
Yes, I am. Thanks, JJ.
@@UncleDoug I thought both amps were similar in sound. If both amps were in big tubes. One amp in each tube I would say the first one was recessed a foot in campared to the second amp sitting right at the entrance of it's tube. Other wise I couldn't hear any difference in the tone, high or lows, anything of both the amps.
@@renegade44040 Thanks for your interesting and unusual input, JJ.
You're my favourite amp teacher. God bless Uncle Doug.
Thanks so much C2. Likewise on the blessing :)
Good to see you back! Great video. Cant wait to see the hot rod with the new carbs on it
Thanks, Ron. Stay tuned for Part II.
Good to see you back, hope everything is ok with you and yours
We were never gone, Nic.....but thanks :)
Thank you Uncle Doug, you really had a lot of work in this video to prepare the Model 1986-Marshall into a 1987-one ! What a great job. Thanks also to Jack and Olli for
doing the Audio-Test. For my opinion the 1986-version is favorite, but as always in liking, you hardly can argue. But I do think that the difference comes from circuit, not from NOS-mustards. But all this seems nothing against the sound that will come out of the exhausters of your V8- 350cui-Chevi-Engine ! :))
You're welcome, Klaus. Thanks for sharing your observations with us.
Thanks for the new video, it's awesome! I agree with most of the other commentors, the 87' version certainly has tighter bottem end and nicer top end, it's hard to pick which one sounds better, they're both great!
Thanks, Thomas :)
Uncle Doug one of the Worlds, the worlds let me rephrase my statement please the world's number one top electrical engineer of any amplifier that ever Sayang to an audience, this is your favorite nephew the one where we couldn't quite fit that Mesa boogie in, nevertheless good to hear Ya Unck, you're still at the top and at the helm God bless take care watching everyone I can.
Wow....thanks so much, Mark.
So glad to see you're back! These videos are always the highlight of my week.
Thanks, B55 :)
The difference wasn't really that apparent to me until your cats played Interstate Lovesong. That single note part, the notes really leapt out. Very nice and a very successful conversion and a very informative video for me! Hopefully I'll be being loaned a 100 watt Plexi soon that needs a bit of love apparently it has two EL34s removed and is also 'running hot' sounds like fun! I also don't know if an MV or non MV amp yet I've asked for pics. Hopefully it's not been too buggered around with
Thanks for your input, H.
Great job as usual. I like the mustard! A fuller mid with less thinness on top. tighter too. Glad your back
BigDave
Thanks, Big Dave. It's always good to hear from you.
I finally finished this saga and bang... Interstate Love Song! I grew up in the grunge era, and not even people my age that followed the grunge bands know this song, at least in my country. Lesson of the day: always keep up with good music.
Amen, HV. Glad you enjoyed it :)
You never cease to absolutely blow my mind. Is there anything you can't do?
And such a beautiful painting by your wife. Helo to Jack & Ollie❤
Thanks so much, Syd......from all of us.
Cold turkey over ! Sweet cats , sweet amp , sweet paintings , sweet guitar ‘n’ mean mean car ! Never leave us Uncle D 😀
Thanks so much, Stewart. I will do my best to be here.....forever ;)
Agreed. Major difference and it will scream as a lead with a little personal adjustment to the users likes when playing precision lead riffs. What a difference! If his other amp sounds the same as the 86' flavor than he's got the best of both worlds. Great Job and nice to see you again in addition to Cassy supervising your every move. :) She's become a little furball who's taken to domestication well and gotten healthy looking! She's a daddies girl, that's for sure!
I really like the new setup on the RatRod. Those carbs on the distributor are going to look sweet! The ports should be cake. They can be done be hand with a cheat block for tapping (for perpendicularity & proper depth), You're only dealing with aluminum (butter).
Can't wait for the next installment and welcome back, we missed you!!!
Thanks so much, PM. It's always great to hear from you.
@@UncleDoug The felling is mutual my friend! The RatRod is really coming along nice! Can't wait to see it finish and hear you foot making sure the accelerator is still working properly! ;)
@@ThePreyMantas I finished installing roll-up windows in the doors today.....what a job !! When they chopped the top, they massacred the doors and window channels. I got dark-tinted glass for the "gangster" look :)
@@UncleDoug Sweet! Looking forward to hopefully seeing that!
@@ThePreyMantas I videoed the ride-along yesterday. Things got a little hectic driving one-handed at 80-90 mph, but we survived :)
Thanks the lord!
Uncle Doug is posting a video. This is probably saving my complete week!
I'll save that for later that evening, sitting on my couch with my dogs, while my wife is at work, eating a lot of stuff, I shouldn't eat and just relax.👏👏👏
Save some room on that couch for us, Oliver :)
Noticeable difference as expected in the bass range. I have noticed as I get older that I lean more towards the low mid to bass range and shy away from the ear stinging high pitch tones. This amp sounds great either way but me personally I would probably shoot for somewhere in the middle of these two circuits. Great video as always!
Thanks, PM2. I agree, shrill tones are quite unpleasant IMHO.
Hi Uncle Doug & Kitties, I hope you had a nice break, good to see you again. I noticed a difference between the 1986 & the 1987 Mustard cap circuit. The 1987 was cleaner sounding, brighter. Was that some Stone Temple Pilots I detected?, & some Joe Walsh. I won tickets to see Warren Zevon, Werewolves of London song, and Joe Walsh came in and did a few songs with Warren, this was in Seattle, Wa., '90's. Be a sad day when you finally call it quits. I have learned so much, Thank you for sharing your knowledge and experience, your a great teacher. Good guitar work by the way. You and your wife are both talented. Till next time, all the best, C.
Thanks so much, Cass. It's always great to hear from you.
So great to see you back Doug. I listened to the sound clips with my eyes closed and wrote down which one I liked better. To my surprise I liked the 1986 with modern caps in the majority of the clips. The 1987 Mustard had more *sparkle* but to my ears less gain. Good video great job.
The difference in gain may be a result of the recording process, Carl. Thanks for your input.
Thanks Uncle Doug! I'm in the midst of converting my 100W Super Lead clone to Super Bass with 6550's. This video is a real help!
You're welcome, H. Good luck with the conversion.
To my old rock and roll ears the 1987 circuit has more treble, presence and is much cleaner than the 1986. Good comparison.
Thanks, Joe. I agree with your assessment.
Hello Uncle... Greetings from Brazil! I'm glad you're back. It seems to me that Mustard Caps make the sound much more velvety.
Thanks, V :)
Wtf UD I stopped receiving you channels notification BUT I’m back and I can binge watch all your videos since the Gibson eh-150! Thanks for all UD!
Thank heavens, K. We'd hate to lose you as a loyal viewer :)
Uncle Doug no way!!! Thanks again, you are a joy for RUclipsLand
Great to see you back Uncle Doug. You've been missed!
Thanks, Norman. It's good to be back.
I to am very glad to see "Good 'Ol Uncle Doug"! The difference was very apparent between the two circuits. The '86 was more bassy, especially on those flappy low notes. The increased treble and mid were audible but the overall tone was similar. It's a Marshall for Gods sake. It was starting to break up a little early to give the "British Sound". The EL34s sounded like they should. Clapton would be proud! Guitars and cars, what a combination. So many similarities, paint, loud sounds and the most important.....they attract beautiful women! You can beat an egg, you can beat a drum, but you can't beat a Hot Rod! Thanxz
You're welcome, ATL. Thanks for all the great comments.
Great video, UD! I believe the Marshall conversion was a complete success. The difference in tone between the two configurations was like night and day. Great playing by your friends, especially song #4 - love me some Funk 49.
Nice work on the 350. Pertronics makes some good fully electronic replacements for older distributors.
I'm guessing an intake manifold for three deuces is hard to come by or ridiculously expensive - I haven't been looking for one so I don't really know.
Nice work all around.
Thanks for all your very nice comments, Spike.
Wow ! This is just what I wanted to see,
I had my 1986 converted to a 1987, and by far, it sounds more suitable for my guitar, and now I blend the 2 channels to suit which has been prepatched internally, I noticed this has a tube rectifier in the same year 1968 they did change over to a solid-state rectify.
Excellent video UD, I will share this with my tech guy......✌🏻
Thanks so much for watching and sharing, Mark. We enjoy hearing from you.
Great video as usual. I have every confidence that the sound difference was due exclusively to the difference in the circuits and had nothing to do with the NOS caps. Regardless I enjoyed it very much, it's always a pleasure watching you guide us from the schematics to the physical implementation.
Don't forget that the values of the capacitors were changed, Bill, not just the type. Changing value really does make a difference.
Yeah that’s what I meant by changes to the circuits.