'82 Marshall 2203 | Correcting the Ground Scheme with the Fewest Changes Possible
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- Опубліковано 2 жов 2024
- As close to stock as I could leave it without the BUZZZZZZZZZ.
For more on Marshall ground schemes:
• Ground Schemes | Part ...
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Your channel inspired me to finally get a tube amp a while ago. Then, it really inspired me to start working on pedals for myself. And now I'm finally getting to the point where I want to use my background in physics to try to design a tube amp.
These videos really insipre me, and really give me a list of mistakes to be aware of!
Amazing how much of a difference that made. Personally, I'm slightly anal when it comes to the noise floor of amps I play. A noise-gate should only be needed for really high gain/metal and not to conceal any amp cranked to it's advertised wattage. Hiss is bad enough. Hum is terrible. Many amps can't pass the test in stock form sadly enough.
I have a opportunity to pick up a Lee Jackson amplifier for next to nothing. Thoughts? Anyone?
after correcting the ground scheme...it went full Thin Lizzy
I have a Marshall 1987x and a 1976 1987 original. They are both noisy. Sometimes not as much and sometimes really noisy. I have customized them both and took them out of the boxes and made them rack mountable using a steel plate on each mounted directly to the steel plates. I have had them like this for a while now. The noise isn't bad but lately it has become almost unbearable. It is definitely a grounding problem and I wondered if you would tell me what I can do to make them quiet. Any help greatly appreciated.
Please, where did you get the stainless-steel screws with locking nylon nuts for grounding? Thank you
Would these kinds of changes be effective in a 4210 circuit? That one is giving me loads of issues in terms of noise. Also very very farty on the bass which I think is because there’s background noise clashing with those notes (the lower notes on a G cowboy chord sound awful).
Can you please use some contact plastic to cover that metal shelid ! just worried you'll get evaporated.
I just discovered your channel and I love it. I own a Framus dragon and am very happy with it. After watching your videos I tried to find information on this amp and its repairability, but found nothing aside from a few mods. Do you know anything about these amps?
@psionic audio
EDIT: apostrophe use
I need that fpr my 50 watt. I think I am more than capable.
It bugs me that the heater wires in these amps are done the way they are. The extra length around the socket doesn't help things - the _most_ correct way would have the heater wires go over the socket. That on top of the less than amazing grounding scheme...
Incredible how when you were touching the foil, it picked up some of the noise from your lav mic. That's some serious sensitivity in the Marshall.
Wonderful tips, thank you.
Made me jump dropping the sheet metal into the amp
This and your other video on ground schemes in old Marshalls have been immensely helpful! Do you have any recommendations on where to buy quality hardware for implementing this kind of setup, or do you find these at your local hardware store?
Fabulous work, Lyle. One of these days I’d like to bring in a couple of my Marshalls for you to work on. A have a 30th anniversary which needs new caps and a ‘78 JMP.
@psionicaudio I love your channel and I’m learning a ton. Going to build my own jmp 2204. In order to ground to your drilled star ground should one use insulating washers on the input jacks and tone knobs or are the washers not necessary in your opinion?
You can have Switchcrafts straight to chassis with no separate wires. But if you use traditional Cliff jacks you have to wire the grounds as shown. I show the pot connections in the video.
@@PsionicAudio thank you so much for the reply! I've been following your amp building advice - started with a Tube Screamer, then built a 5F1 and now a 5E3. Next I'm hoping to do a 2204 Marshall style circuit. I heard you on the Headfirst live stream too and that Mod you talked about at the beginning sounds amazing.
I built a 2204 clone for fun. I did some research on how to wire heaters. I found a method where you run wire across the middle of the tube rather than around the outside. The amp is really quiet. I'm not sure it's "better" or not but it works for me. I never run the amp wide open nobody ever would. That noise is normal I've been playing live with vintage marshalls for years. They typically have no more or less noise than other amps.
I also have a 1982 2203 that has a buzzing issue. It also has a lacking-treble issue (it appears to be stock on the inside). But this video could be very useful for fixing the buzzing issue. Thanks!
Lyle, since this isn't a cathode biased amplifier, from whence would you take the voltage to bias up the heater circuit?? Addng another dropping resistor and filter node from the tail end of the power supply, after the preamp-supply node?
Very interesting about those grounds! I had some serious hum in my '76 JPM's preamp stage as well. The first thing I did was start swapping preamp tubes in V1. It had a cheap generic Chinese tube that I couldn't identify. I tired two new JJs, a Mullard reissue and a Tung-Sol that I had. Not much difference.
I finally found a NOS RCA that knocked 99% of it down to just white noise when preamp and master volume are dimed. Now the preamp is MUCH quieter and actually sounds a lot smoother.
But I do wonder about the grounds too... might be worth having my local tech look at it.
So did something cause the problem? It's a grounding issue? Did the amp ship this way?
Probably. I have an 84 and it's pretty noisy, especially if you put any kind of boost or drive box in front