Schematic and layout of the original Fender amp: ampwares.com/schematics/bassm... For more info, Subscribe to this channel, join us at PsionicAudio, or email us at info@psionicaudio.com.
Ive built a few amps...no way do I pretend to know what you know. That being said I really appreciate this video. I continue to come back to this circuit as my favorite. The amp sounds incredible! Thank you for sharing your work. Much appreciated!
Very useful video, thanks, makes me want to pull open my 6G6-B and see what's in there. Also, I think I've just realised listening to amp repairs is my ASMR (Autonomous Sensory Meridian Response).
One of the sweetest sounding amps I've heard in a long time ,next to your Excalibre ! Wow , I only wish you were closer ,so I could have you put the magic dust on my rig. 🎸🔌
Hey! I use those small trim pots too. I found some 2 watt trimmers on Mouser that are great. They are a great solution for tight spaces or on amps that you don't want to drill holes in. Princeton Reverb's and Tweed/Brown amps are usually what I've used them on. I use twist step bits for chassis holes. They aren't cheap, but they're the right tool for the job. A punch press is great for un-bent chassis, not so much for completed chassis. The step bits leave a great finish too. Lyle is right about grounding. It is so important to an amps sustain and noise reduction. Overall operation really. Oh, and Fender used the yellow Astron and blue Mallory caps in most of the Brown amps. The only one I can think of that didn't really was the Brown Deluxe. Those usually had all blue Mallory caps.
ha! I seen the second video of this amp. it was sounding awesome at the end. this is what I was missing to find out how you got it there. interesting to see your process man, you did right by this one for sure sir.
I love when you critic builds. As a hobbyist I love this. The man ,,,,becoming the guru, the legend!!! I'm trying in comments to introduce you to other amp lovers.
Oh, you didn't do anything wrong. And I very much appreciate your intent. It was just funny to me that within a few minutes of each other one guy calls be a narcissist and you call me a guru. And I'm just kind of a guy trying to do good work.
Well thanks to this video my OCD raged out and I popped open my old bassmans ('62 6G6-B and '66 AB165) that I had done the death cap removal, grounded cord and and polarity switch bypass on many years ago now. Guess who fused neutrals on both and had the ground wire cut shorter than then the other two??? Anyway theyre both fixed now and today Ill be popping open my old '79 2203 as its the only other amp I own thats got a hardwired power cord. Good intel youre putting out there Lyle.
Circuit layout and lead dress is a priority whether you are making a 3 watt SE or a 200 watt high gain amp. The more gain you build in, the more noise policing you will have to do. Thankfully there are many tricks available for builders.
Yes indeed! also those single ended builds can be inherently noisy even on lower gain designs. there's a guy on RU-vid here that builds these big single ended amps. can't remember his name, it's something with a G lol. That's helpful right? Anyway his logo is a G I think. He builds an awesome amp. Kind of unique to go all out with single ended like he does. If I can remember I'll come back and leave it here.
Fascinating as always. WITHOUT ENDORSING any company, would love to hear your thoughts as to which manufacturers are building the highest quality tweeds, blackface, Marshall's etc. I know you haven't seen all of them, but in your experience, who have you seen that is cut from your same cloth? Not kits, but manufactured finished amps. You probably don't want to let that genie out of the bottle! When I get my Excalibre 15, I'll know it's the best it, or any similar amp, can be.
Very nice indeed. Love the sound of the modified bass channel. Did you happen to try the soldano 39k cold clipper value ? I assume that's what's giving it the crunchy , clipping sound in the preamp.
Hey Lyle, i'm really impressed of the sound of this amp, i would like to try the bass side preamp on a 5e3 i don't use , so basically just first stage with cf , then tone stack with 56k slope resistor , and in to v2 a and cathodyne of the 5e3 , do you think it could work? hope you 'll reply , cheers
That's a really nice sounding amp and a fantastic video. Those small orange ceramics - can you share the manufacturer and even supplier of those? I only seem to be able to get crap these days for ceramics (and silver micas). Thanks!
Man, does that sounds nice. Sounds killer on either the Bass or Normal channel and very musically useful. Overdrive, crunch on the Bass channel and some decent headroom for cleans on the Normal channel. You could go from Stray Cats / Rockabilly to classic Blues and Classic Rock. No wonder those original Blond Bassman / 6G6-B amps are coveted by some of my favorite guitar players... Does it clean up nicely when you roll back your guitar volume? Looks like it did.
30 more subscribers since this morning 👍 Edit to add: really interesting review and tweaking of that unusual circuit. I was very familiar with the 5F6-A circuit but that Blonde Bassman is different from everything else. Doesn’t that 10K cathode resistor create a “cold bias” stage? (Similar to a Trainwreck)
so what is the sound difference between the blackface models and the other ones ? and will the strenghten of the power supply give a harder rythem sound ?
Wow! Learning so much from you! Even it I have worked with amps for 25 years (ss amps that is) there is always something new to learn you know..in tube amps that I´m now directed my interest to: .this thing about silver mica caps in higher voltage circuits sm caps are leaky nice to know! is there any more preferred make/version ceramic disc that you prefer?
Thanxl Lyle! got another q about resistors, the seller here in Sweden claims that his 1W carbon film resistors are ok, but the leads are so tiny so I feel there is something wrong here...have you heard about this ?
Man, that amp sounds sweet!!! I love brown/black panel Bassmans. They just don't get enough love. With Fender amps from this era, do you normally ground the bias supply separately like this, or connect it to the same ground node as the PT center tap and reservoir caps?
@@PsionicAudio Thanks! You know, for as many people out there who are making blackpanel Deluxe Reverbs, Princetons, etc I find it interesting that you don't see a lot of people building replica brown/black panel Bassmans. I guess some people just don't want something that lacks reverb and tremolo. Either that or I'm out of the loop on builders who are. I know it took me forever to find a blackpanel bassman chassis for my own custom build. Even then it required a lot of mod work for things to fit correctly.
I love your videos and really appreciate this one and the "secret sauce". Just to clarify for myself, at 25:32 mark of the video you say you replaced with a 1uF cap. I did these mods to my home built amp and used a .1uF. Did I just get confused? Thanks!
@@PsionicAudio Agree and now the channel seems to have lost a little max volume. It was a "beast" in the stock configuration/way louder than the normal channel originally-too much in fact. These mods so far have "tamed" the bass channel significantly. Either I geeked something up or putting the required 1uF cap as directed will help with volume/gain abilities? Thoughts? I do apologize if this is the wrong forum to ask you technical questions. Respectfully, J. P.S. I ordered a 1uF 600v cap and can't wait to complete the mod correctly.
@@PsionicAudio I just received/installed the 1uF cap. WOW-what a great sounding channel that rocks! Thanks again Lyle for sharing your engineering/take on improving this channel. Still got a scratchy treble pot in this channel that is stumping me. Is this normal? because of the gain? I had this scratchy pot before these mods. Cleaning with deoxit D5 has not helped.
Referencing to your comment at 4:50, if a 4 ohm tap is not available as a take-off point for negative feedback, if you double the value of the negative feedback resistor and take the signal from the 8 ohm tap, does that equal the same level of negative feedback that you would get from the 4 ohm tap with the smaller resistor value? I have to also wonder if the feedback signal works differently when you are taking the feedback from an unused tap on the output transformer that would thereby be subject to less impedance variation from the speaker as you are playing through the amplifier....
I could have left the 8 ohm tap connection and doubled the resistor value. But that resistor is buried beneath caps on the board and I had to replace the output jacks anyway, so. In performance it doesn't matter if the NFB is on the "active" tap or not. But the explanation is long and I'm barely into my first cup of coffee.
You would need a 16ohm tap if you wanted to double the feddback resistor value. Voltage wise, the 16 ohm tap outputs twice the voltage of the 4 ohm tap. If using the 8 ohm tap, you'd need a resistor value of 1.414 times what the 4 ohm tap resistor value is.
A spring-loaded "prick-punch" is much more convenient than an ordinary center-punch because it doesn't require a hammer-blow and leaves one hand free to hold the chassis.
@@PsionicAudio I wasn't sure if RU-vid was going to censor it because I used the P word! Anyway, it is a spring loaded punch that you just hold in your hand and push down on, and when you reach the limit of the spring it delivers a recoil shock to the metal you wish to mark, kinda like an impact driver. If you want a deeper divot in the metal, you can just push the punch 2 or 3 times.
I hope your not mad at me. I'm kind of border line Asbergers and can lapse into inappropriate comments that I think are safe. But I appreciate your clearing up grounds in amps. In my studies of amp building that was a challenge for me. I have a rabbit hole question for you. How inportant is keeping heaters in phase?? I know inthe old Fender amps some techs would keep them in phase some would not. Marshall always had different color heater wires and were always wired in phase.
Just curious as to why you don't always use a pointer? As a viewer, I actually find it better...your hands are less in the way. Blondie's sounding nice!
For a guitar, certainly. If I need a 3/8" hole in a 2x4 the regular bit is ok. My point being, never on a chassis or a guitar. And yet people use them.
I really appreciate your vids but did you do something to your mic, it's very sensitive to sibilance, your voice here could have benefited from a POP filter for sure.
I've got a dental issue that makes sibilance tough, even with a de-esser. And still trying to find optimal placement for the Lav mic. Got pops here, but the windscreen thing makes it dark. It's a work in progress unless I get a boom operator...
Sounded fine to me. I'm always surpsised by how well you work on the minute details with a big ole camera in front of your face, blocking the amp. Really like these amp walkthroughs as well as your walkthrough of the work you did on each to improve things. To quote an old Guinness commercial - Brilliant! :)
