New Marshall comes to the fold......

wixedmords

wixedmords

New member
I picked up a good used SLX 100 watter late last week and have just been able to go through it and test it for reliability.

I have cleaned the chassis, head cabinet inside and out, and fixed a couple of small tolex rips. I have cleaned the pots and jacks, tube sockets, and tightened the knobs. I biased the amp, and have been swapping out preamp tubes. It sounds pretty good so far.

It's not new, but I thought you may enjoy it anyway. :wave: : popworm:

Picture_SLXa1.jpg
 
Re: New Marshall comes to the fold......

Nice. If you don't have a footswitch to go between the 2 master volumes, any single-button footswitch will work. I made my own and discovered that a low voltage signal comes down the line so I added a LED to it.
 
Re: New Marshall comes to the fold......

Hey thanks for the good word and information Erik. It did come with a single-button footswitch.
 
Re: New Marshall comes to the fold......

Congratulations, thats a great amp you have there. My favorite part about the amp is the twin gain knobs. They both give you different kinds of distortions and the combinations are endless. Whenever you get a chance can you try setting the gain sensitivity 10 and see if you any sound is still produced. On my amp when it set to that the amp is muted, Erikh has a older generation jcm900, which this amp's based off of, that still produces sound with the setting on 10. I was wondering if that was just a slx thing or problem with my amp.
 
Re: New Marshall comes to the fold......

Nice score. I saw one of those a couple of weeks ago (along with nearly a dozen JMPs, 800s, and NMVs :drool: )

Does it run 5881/6L6s?
 
Re: New Marshall comes to the fold......

JeffB said:
Nice score. I saw one of those a couple of weeks ago (along with nearly a dozen JMPs, 800s, and NMVs :drool: )
Click to expand...

Don't even start talkin' about that place again. :laughing: :laughing:
I would be in hog heaven in that place.

I can't wait to get my MkIII up and running again. Sometime this year hopefully. Then I'd like to get a 2x12 with some nice "clean" speakers. I like how these amps sound with little speaker breakup. It's just so pure and big sounding. The speakers in my 4x12 are really clean.
 
Re: New Marshall comes to the fold......

that is the 900 series amp i wish i had bought many times... i saw a bunch of them come up for sale and turned them down in the late 90's early 2000's.... I really wish i had bought one.... i saw them up for sale anywhere from $400-$600 at the time.....
 
Re: New Marshall comes to the fold......

wow, I thought this had dropped off the board. Thanks again for checkin' in.

There is the footswitchable last gain stage, and the gain knob does go from 1 to 20. It has EL34's in it currently. I take it Jeff and Erik were somewhere where they saw a slew of Marshall's. I think the SLX may be the best deal in the used Marshall market.

I will check that out for your Greendy. If we can't check those things for each other, why are we here? ;) Any specific settings other than the sensitivity on 10? Just give me an hour or so and I will PM you.
 
Re: New Marshall comes to the fold......

Actually, Jeff told me about the place with the slew of Marshalls. He was very good at making a visual in my head with the descriptions. The dirty rat bastard. :laughing:

The footswitch on the SL-X, and the MkIII, just switches between the two Master Volumes. It doesn't add or take away a gain stage. The Gain Sensitivity (11-20) on yours controls the amount of gain from that additional pre-amp tube (V3 in your case). In mine, that same control adjusts the amount of gain from a diode rectifier.

Post those results with the Gain Sensitivity all the way down here. I'm curious too. IIRC, that is normal behaviour for the SL-X.
 
Last edited:
Re: New Marshall comes to the fold......

wixedmords said:
I will check that out for your Greendy. If we can't check those things for each other, why are we here? ;) Any specific settings other than the sensitivity on 10? Just give me an hour or so and I will PM you.
Click to expand...

I think thats basically it, the amp really simple to use. If want to try any pre-amp tubes out I have found that the chinese 12ax7's really warms up the tone and tung sols give a nice clear, brighter tone, both in the v1 positions. I think both are supposedly good for high gain. I haven't tried if lower gain tubes sound good in it yet, but I think I might get some later to try. Thanks again for checking the stuff out.
 
Re: New Marshall comes to the fold......

ErikH said:
Actuall, Jeff told me about the place with the slew of Marshalls. He was very good at making a visual in my head with the descriptions. The dirty rat bastard. :laughing:

The footswitch on the SL-X, and the MkIII, just switches between the two Master Volumes. It doesn't add or take away a gain stage. The Gain Sensitivity (11-20) on yours controls the amount of gain from that additional pre-amp tube (V3 in your case). In mine, that same control adjusts the amount of gain from a diode rectifier.

Post those results with the Gain Sensitivity all the way down here. I'm curious too. IIRC, that is normal behaviour for the SL-X.
Click to expand...

You got me on the footswitch as I haven't tested exactly what it does, other than keeping it on because of what I thought was added gain. I see now that the each channel is controlled by a different master volume. The funny thing is, that channel B sounds a bit more airy and a bit less middy than channel A. I am thinking that it is due to the footswitch LED.


Results of what Greendy spoke of:

I find the same thing. NO sound when the sensitivity is on 10. Tested it on both channels. That would make one believe it is really more an indication of 0.
 
Re: New Marshall comes to the fold......

It's a single channel amp with two switchable master volumes. There is no second channel. I'll have to take a look at the schematic but that more airy and less mids on MV B isn't due to the footswitch LED. That's not affecting the sound at all. It's just an indicator.
 
Re: New Marshall comes to the fold......

ErikH said:
It's a single channel amp with two switchable master volumes. There is no second channel. I'll have to take a look at the schematic but that more airy and less mids on MV B isn't due to the footswitch LED. That's not affecting the sound at all. It's just an indicator.
Click to expand...


Ah, I understand. The difference is small between the volumes, but noticable.
 
Re: New Marshall comes to the fold......

wixedmords said:
Ah, I understand. The difference is small between the volumes, but noticable.
Click to expand...

Yeah, it is noticeable. You can set them both to the same spot on the dial and B will always be a touch louder. Hence one for rhythm, one for lead.

I'm looking at the schematic for the MkIII and the two MV's have the same components and route from/to the same path. The switching network is hooked up off an IC pin for MV B. That's the only difference I see. It could be a simple component difference that just isn't obvious on the schematic. I plan on opening mine up later this week to take some pictures of the insides and the tranny so I can get a new one for it. Also need to get fuses and tubes while I'm at it.
 
Re: New Marshall comes to the fold......

ErikH said:
Yeah, it is noticeable. You can set them both to the same spot on the dial and B will always be a touch louder. Hence one for rhythm, one for lead.

I'm looking at the schematic for the MkIII and the two MV's have the same components and route from/to the same path. The switching network is hooked up off an IC pin for MV B. That's the only difference I see. It could be a simple component difference that just isn't obvious on the schematic. I plan on opening mine up later this week to take some pictures of the insides and the tranny so I can get a new one for it. Also need to get fuses and tubes while I'm at it.
Click to expand...

I am sorry Erik. I think what I meant got lost in my wording or my usage of terms. I did not mean take you out of your way.

The sound that comes from using volume B is a bit more airy and less middy than volume A. It is somewhat like when you kick on an eq pedal, but only a slight change (say 3-5%). I believe you when you say the volumes are virtually using the same path. I am going to chalk it up to something small, like you said, until something makes a greater change, if it ever seems to change.

I think I made it seem like it was a concern to me, but I actually like it. I may not look upon it so positive in a playing out situation, but the amp doesn't have true separate channels so it won't be a clean/distorted situation, it would more than likely be a lead/distorted or a distortion1/distortion2 situation. I kinda look at Marshall's as being the later 2 rather than the prior. Most Marshall's have a clean channel that is a bit compressed and takes pedals well. So that is how I approach them.
 
Re: New Marshall comes to the fold......

You weren't taking me out of my way. Don't worry about it. :) Just sharing info is all. I've been curious about the inner workings of those two master volumes for some time and finding out the differences. Even though the schematic shows zero differences, other than the switching network, there has to be something else there accounting for that little difference in tone.

There is a chance I may have my MkIII back in working order sooner rather than later. I just need to check and see what else I need besides a new PT, tubes, fuses and a rubber handled screwdriver or two.
 
You must log in or register to reply here.
Back
Top