Early Mark 1

[DC3 Gridlock]

I noticed that it doesn’t have the resistor on the plate of one of the output valves and the wire being wrapped around shielded cable wires.

Regards

Mark

Thanks, PM sent on my conversation with Mesa.

Should I be worried about the missing resistor and take it to my tech?

Thanks again.
Grid

 

[DavidMenke]

Thanks, PM sent on my conversation with Mesa.

Should I be worried about the missing resistor and take it to my tech?

Thanks again.
Grid

Best person to speak to at Mesa is Mike Bendinelli who has been there almost since the beginning. You could also send the amp to them, just the chassis, for cost, and they can go through and restore it to it's original state. The Mark series of amps may even be able to retro fit your amp into a new cabinet. (worth checking out) Or even a solid wood cabinet could be a choice. Those Mark one series are a keeper! Fix it up and play it for the next 50years.

 

[mark1406]

Thanks, PM sent on my conversation with Mesa.

Should I be worried about the missing resistor and take it to my tech?

Thanks again.
Grid

No I wouldn’t worry about it at all. Some amps had it and some amps didn’t.

Regards

Mark

 

[Don]

What does the Boost switch do?

 

[mark1406]

What does the Boost switch do?

The boost lifts the earth off the mid pot or in this case the mid resistor in the tone stack which removes the load presented by the tone stack and changes the tone of the amp.

 

[DC3 Gridlock]

The boost lifts the earth off the mid pot or in this case the mid resistor in the tone stack which removes the load presented by the tone stack and changes the tone of the amp.

I thought that the boost took the amp from 60 watts to 100 watts. I does sound better to my ears with it on.

 

[Don]

The boost lifts the earth off the mid pot or in this case the mid resistor in the tone stack which removes the load presented by the tone stack and changes the tone of the amp.

That's what I assumed, but I couldn't quite follow the wire.

 

[mark1406]

That's what I assumed, but I couldn't quite follow the wire.

Okay, I was talking with reference to my original Mark 1 amp. Given the position of the switch on your amp, I would agree that it is the 60/100 watt switch. This works by open circuiting the cathode to ground connection of two of the output valves.

Regards

Mark

 

[DC3 Gridlock]

I am really liking the amp, I switched power around (matched sets inner and outer) tubes per Mesa’s comments and cleaned the reverb tank connections.

I would think with a band, I would probably only need an OD pedal for leads. Nice edge of break up tones with a little volume.

 

[585960]

2 nearly the same amps from 1977.

 

[585960]

 

[585960]

 

[585960]

 

[mark1406]

I am really liking the amp, I switched power around (matched sets inner and outer) tubes per Mesa’s comments and cleaned the reverb tank connections.

I would think with a band, I would probably only need an OD pedal for leads. Nice edge of break up tones with a little volume.

Santana didn’t use an overdrive pedal with these amps. I don’t know what settings he used, but he could get the amp to feedback on various notes.

Regards

Mark

 

[FedWar]

Santana didn’t use an overdrive pedal with these amps. I don’t know what settings he used, but he could get the amp to feedback on various notes.

Regards

Mark

there are some posts online taken from magazine of that time that state that he and many other were using the magic
" 7 7 7" values,
vol 1 = 7, vol 2 = 7, master = 7.
With this setting not only is the amp LOUD, and with the master this high distortion is also added by power section (old marshall style).

 

[mark1406]

there are some posts online taken from magazine of that time that state that he and many other were using the magic
" 7 7 7" values,
vol 1 = 7, vol 2 = 7, master = 7.
With this setting not only is the amp LOUD, and with the master this high distortion is also added by power section (old marshall style).

I’m not sure what you mean by “power section (old Marshall style).”
Is that a reference to the P.I. stage?

Regards

Mark

 

[edge59AlnicoIV]

I’m not sure what you mean by “power section (old Marshall style).”
Is that a reference to the P.I. stage?

Regards

Mark

The early Mark 1 had the Tweed Bassman/Marshall PI, Santana and others said it was too shrill so Randall changed the PI to Blackface Twin style PI and the Presence control then became the a high cut or treble roll off at the master volume before the PI input seen in the re-issue. The King Snake had a switchable Tweed/Blackface presence control.
As a footnote, Santana's original snakeskin Mark 1 did not have cascaded gain staging according to Randall Smith, it also did not have the PI negative feedback loop resistor, Carlos said "that amp really pops!"
Though it had the PRE AMP BOOST that was a push/pull pot and had a foot switch jack and got a really nice boost, without being so muddy like the later version.

 

[edge59AlnicoIV]

The early Mark 1 had the Tweed Bassman/Marshall PI, Santana and others said it was too shrill so Randall changed the PI to Blackface Twin style PI and the Presence control then became the a high cut or treble roll off at the master volume before the PI input seen in the re-issue. The King Snake had a switchable Tweed/Blackface presence control.
As a footnote, Santana's original snakeskin Mark 1 did not have cascaded gain staging according to Randall Smith, it also did not have the PI negative feedback loop resistor, Carlos said "that amp really pops!"
Though it had the PRE AMP BOOST that was a push/pull pot and had a foot switch jack and got a really nice boost, without being so muddy like the later version.