Amp Question - What's Up With Knob Placement?

[ChrisN]

Beyond aesthetics or style considerations, is there a reason some amps have their controls on top while others have theirs on the face?

I play facing my amp while it sits angled in a floor rack, as that gives me the best sound. I have amps with top mounted controls (at the back of the top panel) and amps with the knobs on the front panel. As I'm sitting in my chair leaning forward to make adjustments, guess which approach I prefer.

Now, if I was sitting next to the amp as it faced out to an audience, the top mounted controls certainly make sense there, but given that amps serve the same general purpose (playing to an audience and/or practicing), why do the makers place their controls differently?

[Bob Womack]

It all has to do with chassis orientation. If the chassis is oriented with the transformers protruding towards the front and the tubes hanging off the bottom (ie. Fender tweed), the controls will be on top. If the chassis is oriented with the tubes and transformers hanging from the bottom (ie. Fender blackface), the controls will be at the top and either front or back. If the chassis is oriented with tubes and transformers on top (ie. Marshall), the controls will be at the bottom at the front of back. Why the difference? Mainly design philosophy and style. The earliest amps were designed to sit in front of the player so the controls were on the back.

Bob

[ChrisN]

Originally Posted by Bob Womack

It all has to do with chassis orientation. If the chassis is oriented with the transformers protruding towards the front and the tubes hanging off the bottom (ie. Fender tweed), the controls will be on top. If the chassis is oriented with the tubes and transformers hanging from the bottom (ie. Fender blackface), the controls will be at the top and either front or back. If the chassis is oriented with tubes and transformers on top (ie. Marshall), the controls will be at the bottom at the front of back. Why the difference? Mainly design philosophy and style. The earliest amps were designed to sit in front of the player so the controls were on the back.

Bob

That's helpful. And by "designed to sit in front of the player" I'm assuming you mean the speaker is pointed out toward an audience, and not what I'm doing by having it the speaker aimed back at me.

Thanks Bob

[muscmp]

some of the earliest amps had the chassis in the bottom of the cabinet. just think how hard that would be to tweak from sitting in a chair, or anywhere for that matter.

play music!

[Bob Womack]

Originally Posted by ChrisN

That's helpful. And by "designed to sit in front of the player" I'm assuming you mean the speaker is pointed out toward an audience, and not what I'm doing by having it the speaker aimed back at me.

Thanks Bob

Yep. Early Epiphone Electar Amps were designed to look like a big band music stands.




Bob

[clintj]

Fifties and earlier Fender amps were normally placed in front of the musician, which made sense early on. Leo Fender's first guitars were lap steels and were sold in pairs with an amp, so having an amp easy to adjust while sitting at your instrument was functional. Around 61 or 62, Fender shifted to front mounted controls on the blonde tolexed amps. You'll also notice around this time that the amps moved to the back of the stage to make room for the musician to be out in front - there was no way Chuck Berry was going to sit in a chair!

When Marshall started, they copied (okay, flat out cloned) the late fifties Fender Bassman but with the chassis rotated so the tubes were on top and controls in front. If you orient the two amps the same way, the control panels are identical in layout including the jacks being to the right. That way you could put the head cab on top of the speakers and have your controls right at your fingertips. There's technical reasons for the tubes to be normally vertical, but I'll not get into that.

[ChrisN]

Originally Posted by Bob Womack

Yep. Early Epiphone Electar Amps were designed to look like a big band music stands.

Bob

So that top panel orientation makes sense - player can look down and easily see what's up, reach down to tweak. My S/S Vox 15R with the top panel controls (at the rear of the top) has them flipped, so that if I had it by my side and looked down, everything'd be upside down, relative to the one you provided. The Vox apparently is designed to have you adjust from the front of the amp, but the controls are placed at the back of the top, making them all but inaccessible if it's leaned back on a floor stand. Worst of both worlds, it seems.

My peavey's got a nice fender-type front panel, and my mustang's got a top-mount oriented like the Vox's but at the front of the top, rather than at the rear. Learning every day.