1973 Marshall SLP 100 Ohm settings markings erased

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weldart
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1973 Marshall SLP 100 Ohm settings markings erased

Post by weldart »

Hey,

The ohm settings markings on my 1973 SLP have been erased from the metal backplate of the amp cabinet... can anyone tell or show with a photo which switch position is for what ohm speaker setting?

Thanks!

Artmetal
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ToneMerc
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Re: 1973 Marshall SLP 100 Ohm settings markings erased

Post by ToneMerc »

I don't recall it ever being displayed on the backplate itself. The Z was displayed in the switch plug window, you must be missing the plug?

The best as I can recall is that the OT actual wired switch connections are inverted from the plug window. I would verify how the OT wires are connected to the switch housing. The plug pins timed straight up should be equal to 8 ohms.


4 ohms (blk)
8 ohm (yel)
16 ohms (grn)

TM
Cliff Schecht
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Re: 1973 Marshall SLP 100 Ohm settings markings erased

Post by Cliff Schecht »

Easiest thing to do is to grab a 16 Ohm speaker and plug it in. The loudest position is 16 Ohms and the quietest is 4 Ohms. I don't recommend doing a 4:1 mismatch for long, especially with an older Marshall, but you should be able to quickly tell which selector position is what just by volume.
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selloutrr
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Re: 1973 Marshall SLP 100 Ohm settings markings erased

Post by selloutrr »

ToneMerc wrote:I don't recall it ever being displayed on the backplate itself. The Z was displayed in the switch plug window, you must be missing the plug?

The best as I can recall is that the OT actual wired switch connections are inverted from the plug window. I would verify how the OT wires are connected to the switch housing. The plug pins timed straight up should be equal to 8 ohms.


4 ohms (blk)
8 ohm (yel)
16 ohms (grn)

TM
The above colors are correct for the 100W Marshall
Brown is Common.

The faceplates are not marked with the ohms the socket is labeled and visiable thru the little window of the selector plug.
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Reeltarded
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Re: 1973 Marshall SLP 100 Ohm settings markings erased

Post by Reeltarded »

[img:800:536]http://ianparr.com/marshall/DSC_0044.jpg[/img]

As Googled. It's not just ink.. a picture of your's might tell a story we haven't heard yet. :)[/img]
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
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ToneMerc
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Re: 1973 Marshall SLP 100 Ohm settings markings erased

Post by ToneMerc »

Yep, that's it

plug pins timed at ctr pin & 2 O'clock = 4 ohms.

plug pins timed straight up = 8 ohms.

plug pins timed at ctr pin & 10 O'clock = 16 ohms.

TM
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ToneMerc
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Re: 1973 Marshall SLP 100 Ohm settings markings erased

Post by ToneMerc »

Vintage style switch plug


[/url] http://www.guitarnucleus.com/gnstore/am ... m#marshohm [url]
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