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Messages - El Scorcho

#1
The Newcomer's Forum / Re: Marshall 5010 Needs Help
December 19, 2021, 05:06:48 AM
Hey, sorry I haven't been on the forum in awhile, but thanks so much for taking the time and trouble to trace out that schematic! I really appreciate it! I've had to shelve alot of projects since the Covid sitch.
Lately I had the thought of modding the circuit to be more like a  Guv'nor pedal with an led clipping mod, or even dropping in a jfet jcm 800 preamp pcb, although just putting a pedal in front of it would do pretty much the same thing.
#2
I don't want clean AT ALL on my Marshall, i just want it to sound like a Marshall instead of a cheap practice amp! My old Lead20 sounded great-it just could't be heard over a drummer. It had a sweet sound, wheareas this particular 5010 ( and perhaps the Red McKenzie version in general) sounds like a turd smells. The later versions with the horizontal and single inputs sound really good, and I don't know why mine doesn't- but it really doesn't.
#3
The Newcomer's Forum / Re: Marshall 5010 Needs Help
April 29, 2018, 12:53:22 PM
The IC is an LM1458.
#4
The Newcomer's Forum / Re: Marshall 5010 Needs Help
April 29, 2018, 08:03:22 AM
Ok. Here goes.
#5
The Newcomer's Forum / Re: Marshall 5010 Needs Help
April 24, 2018, 03:03:45 PM
In my amp Tr1 is an N3819, though according to the (inaccurate) 5010 schematic it should be a BC184.
#6
The Newcomer's Forum / Re: Marshall 5010 Needs Help
April 24, 2018, 01:45:07 PM
I tried to post the link to the google image I found of the pcb, but it doesn't seem to work.
https://www.worthpoint.com/worthopedia/marshall-5010-master-lead-combo-pcb-538953534
#7
The Newcomer's Forum / Re: Marshall 5010 Needs Help
April 24, 2018, 01:30:07 PM
I'll go back and find that image, jazz bass. In the meantime, I was on the Marshall forum trying to find out anything I could about the JM69 pcb and not having much luck-until I stumbled across a post about a guy with a similar problem to mine, only with his bass amp. The schematic was for his 5503 30 watt bass amp listed a certain pcb, but his had a JM69 board instead, and the components didn't match. So I ran down that schematic, and found it is much more similar to mine. In fact, the transistor values that seemed out of place on the 5010 schematic match. I think the Red McKenzie version of the 5010  is essentially a bass amp.
#8
The Newcomer's Forum / Re: Marshall 5010 Needs Help
April 24, 2018, 06:33:38 AM
Interesting development.

I found the exact same Red McKenzie version of this amp for sale locally, and contacted the seller to see if he would be willing to let me take a picture of the circuit board to compare it to mine. While I didn't expect him to allow it, he was kind enough to send me number of google links, which I DIDN'T expect, one of which provided some very useful insight.

Apparently the Red Meckenzie version uses a JM69 circuit board, and the only available Marshall schematic for the 5010 is a JMP27A board.

One of the links provided by the gentleman was from an auction site where someone gutted his 5010 to convert it to a tube amp, and was selling the old board - which in this case happened to match mine, a JM69.

Zooming in on the picture confirms Phatt is correct - D1 is a cap, and D2 is vacant, just like mine. Also, I appear to have a number of factory caps (blue in the pic) replaced with Orange Drops; C 1,4,6,8,9,12, and 16.
#9
The Newcomer's Forum / Re: Marshall 5010 Needs Help
April 21, 2018, 02:57:22 AM
Here's what I've got so far....
#10
The Newcomer's Forum / Re: Marshall 5010 Needs Help
April 18, 2018, 03:39:48 PM
Thanks for having a look at my post, I've seen some of your other posts on these Marshalls, and was hoping you'd chime in.  Those Johan Segborn videos on YT inspired me to buy another one. I would LOVE for mine to sound like that. I had Lead 20 years ago that sounded great, but I couldn't hear it very well over a drummer. This particular 5010 has the volume, but an unpleasent sound. What's frustrating is the sound is 'in there', but with a crappy coating that can't be dialed out.
    I've been busy with exams, but I'm ready to open it up again.
#11
The Newcomer's Forum / Re: Marshall 5010 Needs Help
March 30, 2018, 10:52:58 AM
 And, yeah the way C2 is stuck in there doesn't look like a factory job.
#12
The Newcomer's Forum / Re: Marshall 5010 Needs Help
March 30, 2018, 10:48:39 AM
Thanks for having a look at guys, I really appreciate it! I'll order some parts.
  Phil, do you think I should use the 1N914's in the schematic, or could I go with LEDs?
#13
The Newcomer's Forum / Re: Marshall 5010 Needs Help
March 28, 2018, 08:51:04 AM
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#14
The Newcomer's Forum / Re: Marshall 5010 Needs Help
March 28, 2018, 08:50:19 AM
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#15
The Newcomer's Forum / Re: Marshall 5010 Needs Help
March 27, 2018, 02:48:33 PM
  I found a short video of one just like mine, with the same ugly crossover distortion. Funny, the horizontal and single input versions seem to all sound great.

Watch "Marshall Master Lead Combo - Fizzy Distortion" on YouTube
https://youtu.be/y1osT39OSjs