Dumb layout question - why don't they go left to right?

[theRagman]

So, I'm new at this, which means I might as well jump in with a really dumb question to get started:

Why aren't layouts customarily drawn from left to right like schematics (input and preamp on the left, progressing to the PI, then the power section, for example)? I'm assuming there's a very good reason for this, but as I start drawing up my first layout, mentally flipping everything over from the schematic feels weird and unnecessary. Obviously, I can draw my own layouts any way I want, but there's gotta be a good reason for the standard convention, and before I do something ridiculous, I'd like to find out what that reason is...

Thanks!

[passaloutre]

Flip the page around

[shooter]

think of schematics like a novel, they are "read"
think of layouts like a map, still read but they show you where you are "in the world", or board or...

[sluckey]

I guess you have not seen a Hoffman layout?

     https://el34world.com/Hoffman/files/Hoffman_5E3.pdf

[theRagman]

I guess you have not seen a Hoffman layout?

     https://el34world.com/Hoffman/files/Hoffman_5E3.pdf

I had not, but I sure am glad to see this one. It makes sense to me! :)

[dogburn]

My guess is that Leo Fender did it that way because that's how he had his employees orient things when they built the amps. And so now it's become the more or less standard way to do them (except for Hoffman of course). He did like to standardize things, even if they didn't always make the most sense (see Tremolo vs. Vibrato terminology).

There may be some other explanation, but I don't recall seeing original layouts for amps by other manufacturers (I'm sure someone here could point some out).

[theRagman]

My guess is that Leo Fender did it that way because that's how he had his employees orient things when they built the amps. And so now it's become the more or less standard way to do them (except for Hoffman of course). He did like to standardize things, even if they didn't always make the most sense (see Tremolo vs. Vibrato terminology).

There may be some other explanation, but I don't recall seeing original layouts for amps by other manufacturers (I'm sure someone here could point some out).

A great deal of amp stuff does seem to boil down to "because that's the way Leo did it..."

[sluckey]

When I first started doing layouts, I thought the same thing. Why is the layout backwards as compared to the schematic? But after doing a few "backward" layouts, I've become quite familiar and comfortable working with them and building projects from the backward layout. These days I want my input on the top right, pots across the top, tubes on bottom. Now a "left to right" layout looks backwards! When I look at Hoffman's layouts for more than a few seconds, I usually rotate the drawing 180°. Now it looks mo better!   

[HotBluePlates]

Why aren't layouts customarily drawn from left to right like schematics (input and preamp on the left, progressing to the PI, then the power section, for example)? ...

My guess is that Leo Fender did it that way because that's how he had his employees orient things when they built the amps. ...

It's much simpler than that:  the layout is arranged exactly like the object in physical space.

   - When you stand in front of the tweed Deluxe and look at the panel, it is laid out left-to-right the way you wanted.

   - To get at the electronics, you have to remove the panel off the back of the amp.

       

   - Now that you're looking at the chassis from the opposite side (back, not front), the circuit runs right-to-left.
   - The layout is oriented exactly like the item you will work with (inputs to the right, power transformer to the left):

       


Now we flash-forward a few years, and Fender has altered their cabinets & chassis, and began making the control-panel front-facing.

   - Looking from the front, we still have our expected left-to-right control layout:

       

   - However, we don't disassemble this model solely by removing a back panel.  We remove an upper back panel, then undo the chassis straps.  The chassis can only come out by sliding out the back of the amp:

       

   - When we look down at the object in our hands at the moment we slide the chassis out the back, the back-apron is closest to us, and the front-panel is furthest away.  The input jacks are over to our right, and the whole circuit runs right-to-left.  And look at that, Fender drew the layout in the exact orientation we see the electronics when pulling the chassis from the amp.  Inputs to the right, and power transformer to the left:

       

[bmccowan]

In the southern Hemisphere, they do it exactly the opposite.
Just kidding of course. Great explanation from HPB. But I am wondering if Ragman was curious as to how the actual amp is laid out - preamp to power amp sections. For that I think it was likely an arbitrary decision with mfgs, including fender, seeking consistency for their workers. In looking at old PA amplifiers there is much less consistency with the circuits being a scrambled point-to-point.

[Loomer]

My guess would be that as you removed the back panel of a combo amp the board would present itself as you see in most layouts, so it made sense to stick to that?

[theRagman]

Why aren't layouts customarily drawn from left to right like schematics (input and preamp on the left, progressing to the PI, then the power section, for example)? ...

My guess is that Leo Fender did it that way because that's how he had his employees orient things when they built the amps. ...

It's much simpler than that:  the layout is arranged exactly like the object in physical space.

   - When you stand in front of the tweed Deluxe and look at the panel, it is laid out left-to-right the way you wanted.

   - To get at the electronics, you have to remove the panel off the back of the amp.

       

   - Now that you're looking at the chassis from the opposite side (back, not front), the circuit runs right-to-left.
   - The layout is oriented exactly like the item you will work with (inputs to the right, power transformer to the left):

       


Now we flash-forward a few years, and Fender has altered their cabinets & chassis, and began making the control-panel front-facing.

   - Looking from the front, we still have our expected left-to-right control layout:

       

   - However, we don't disassemble this model solely by removing a back panel.  We remove an upper back panel, then undo the chassis straps.  The chassis can only come out by sliding out the back of the amp:

       

   - When we look down at the object in our hands at the moment we slide the chassis out the back, the back-apron is closest to us, and the front-panel is furthest away.  The input jacks are over to our right, and the whole circuit runs right-to-left.  And look at that, Fender drew the layout in the exact orientation we see the electronics when pulling the chassis from the amp.  Inputs to the right, and power transformer to the left:

       

Well, that's about as complete an explanation of that as I could have asked for. Thank you!