Devil Magnum

[JIO]

I do all the engineering work in CAD (Qcad, these days). That is, I do all the detail work, fitting all the hardware, making sure the strings are positioned correctly and have the right clearance and adjustment range, locating the pickups and controls, etc. The functional part of the design process.

While doing that, I draw out the perimeter shape and other curved shapes like internal chambers and control cavities, using the Polylines function in CAD. It establishes the curved shapes as a series of points with short straight line segments between them. It's quick and simple, and it makes sure that the curved shape fits correctly with the core stuff. I typically draw them with the points anywhere from 1/4" to an inch apart. Those Polylines get copied into other layers in the drawing, to become patterns and templates.

To make the patterns and templates, I print the Polylines out full size, with the important reference holes to locate them. I usually print them on heavy 28lb paper. I transfer the Polylines and reference hole locations to pieces of 3/4" MDF, sometimes using old-fashioned carbon paper under the paper printout. Other times I cut out the paper template and draw around it with a pencil. What is drawn on the MDF is the Polyline; points and segments.

I saw out the MDF and smooth it all out with spindle sanders and hand files. This is where I convert the Polyline into an actual curved line. I'm careful to meet all the points and make a smooth curved shape between them. The MDF pattern becomes the Master Pattern. It is the actual shape that all the instruments will be cut to. It's a full size physical thing that I can look at and feel with my hands, and verify that the shape is what I want.

In the computer, I leave the perimeter shape as a Polyline. It's not the actual curved line that's on the Master Pattern, but it's an accurate representation of all the critical points. Yeah, I could smooth the Polyline using a Polyline Smoothing function, or paste it into an Illustrator-type program and fit a Bezier curve to it. But that's only if I wanted to make the CAD drawing "pretty" to show to people. Generally not worth the extra time to me.

That's my design process: I use Qcad to establish all the important dimensions and locations. I use Polylines within Qcad to rough out all the curved shapes. Then I transfer the Polylines to hard MDF patterns, and do the final smoothing of the curved shapes with tools, on the MDF.

Thanks for describing your process Bruce - reading it I can see how going though a measured and systematic series of accurate steps filtered through technology eliminates drama from a build!

 

[JIO]

Body bubble-wrapped securely in a box and off to Pat this morning. Usually about 3 weeks to a month it'll be back with a fantastic look that matches the finish he did on the neck.

This is the Ovation Magnum with the look Pat will mimic. Natural gloss with a tobacco halo.

And this is an Ampeg ASB-1 Devil Bass for halo reference. (just not red!) Maybe Bruce has mentioned this before as he is the authority on these basses, but the ASB-1 was designed by a former coffin maker named Mike Roman who was an employee at Danelectro in the late '60s. Here's Bruces page on the Devil Bass with all related info. Johnson's Extremely Strange Musical Instrument Company Home Page

I found this entry from Bruces page interesting:

"At least one Devil Bass was made with an asymmetrical body, where the upper half of the body including the upper horn is shifted about 2" towards the headstock. A photo of this instrument appears in a late '66 Ampeg brochure, so it was probably an early prototype. If anyone has any information about a Devil Bass like this, please tell me!"

@Bruce Johnson Do you have a picture of that brochure page? I would love to see that asym prototype.

 

[Bruce Johnson]

"At least one Devil Bass was made with an asymmetrical body, where the upper half of the body including the upper horn is shifted about 2" towards the headstock. A photo of this instrument appears in a late '66 Ampeg brochure, so it was probably an early prototype. If anyone has any information about a Devil Bass like this, please tell me!"

@Bruce Johnson Do you have a picture of that brochure page? I would love to see that asym prototype.

I did some searching, and I couldn't find that picture. I believe it is in the Ampeg book. We found it in an old brochure while doing the research for the book in 1996 or so. It looked about like a "normal" Devil Bass, but with the upper half of the body shifted about 2" forward. The horns were equal in size and shape, just offset. And the pickguards were about the same, just shifted offset. In 25 years, I haven't heard another peep about that instrument, where it is or what happened to it. I assume that it was a one-off prototype.

For your amusement, here's a bass and guitar pair that Mike Roman built in the years after he left Ampeg; around 1970. We know of a few of these; two or three.

 

[JIO]

I did some searching, and I couldn't find that picture. I believe it is in the Ampeg book. We found it in an old brochure while doing the research for the book in 1996 or so. It looked about like a "normal" Devil Bass, but with the upper half of the body shifted about 2" forward. The horns were equal in size and shape, just offset. And the pickguards were about the same, just shifted offset. In 25 years, I haven't heard another peep about that instrument, where it is or what happened to it. I assume that it was a one-off prototype.

For your amusement, here's a bass and guitar pair that Mike Roman built in the years after he left Ampeg; around 1970. We know of a few of these; two or three.

View attachment 4215948

View attachment 4215949

Excellent! Thanks Bruce! Reminds me a little of one of my favorite bass designs. (and finishes)

Marleaux Pagelli

...and there is the Peavey B-Quad from the mid '90s w/Gildaxe finish

...and my own 'long horn' oriented SuperB designs -

...and Supernova-

... and Super SLX -

...and Supersonic -

 

[Flying B]

This is looking great, looking forward to seeing that paint job.

I'm in the planning stage for my next build which will have identical pickup and wiring, what is your measurement for the pickup placement?

 

[JIO]

This is looking great, looking forward to seeing that paint job.

I'm in the planning stage for my next build which will have identical pickup and wiring, what is your measurement for the pickup placement?

I centered the poles at 13.25" from the 12th fret. DS/BS pu's can be positioned with the poles down or up and although they tend to be positioned poles up, I position them poles down. With one pu it can be positioned either way and look ok but with two it matters more depending on where they are installed. If they were flipped on my Deadlybird IV the bridge pu would invade the bridge.

 

[Flying B]

I centered the poles at 13.25" from the 12th fret.

Great cheers, 34" scale I'm assuming?

 

[JIO]

Great cheers, 34" scale I'm assuming?

Yes, 34" scale. I discovered the position on my 1st Teiscobird. (top) I don't even remember how I determined this, but it works really well there. I've never owned a MM Stingray, but it might be in a similar location. It's also where my right hand hangs out (close to the bridge) so a lot of time I'm right over the poles. I also use a pick and palm-mute right in front of the bridge so it positions my right hand over the pu.

 

[daveman50]

The pickup position is like (same as?) a Rickenbacker bridge pickup.

 

[Bleecker]

Is this inspired from the rare Fender Standard Performer? Love the color on this one!

 

[JIO]

The pickup position is like (same as?) a Rickenbacker bridge pickup.

Interesting...

 

[JIO]

View attachment 4218922

Is this inspired from the rare Fender Standard Performer? Love the color on this one!

Yes - I made my Supersonic w/o ever having played/held an '85 Performer after years of appreciating that model/design. After it was done, I owned a vintage ('85) Performer for a brief time. Really cool bass - if I didn't have my Suprsonic I would have keep it.

The colour (of mine) is Firemist Gold Metallic, used on late '60s GTO's. The '85 was Jade Metallic or something...

 

[daveman50]

Interesting...

check this out - not my post ...
Ultimate Pickup Placement Comparison

 

[Beej]

check this out - not my post ...
Ultimate Pickup Placement Comparison

Dang, I've looked for one so comprehensive before and not found this one. Shame he didn't line them up at the bridge witness line correctly, the chart has been rendered inaccurate.

 

[ardgedee]

Dang, I've looked for one so comprehensive before and not found this one. Shame he didn't line them up at the bridge witness line correctly, the chart has been rendered inaccurate.

Yeah, it's surprisingly tricky to get these right. I made this last year by lining up the 12 fret and G string witness line but make no claims of accuracy -- I know positions are in error but I just don't know which ones are off in which direction.

 

[daveman50]

Adding the Rickenbacker to the mix is further complicated by the slightly different scale length (33.25). But by eyeball, the Rick bridge pickup is slightly further from the bridge than the MM.

P.S., the reason I'm slightly obsessive about this is that I've had a Rick for a very long time (coming up on our 48th anniversary, hard to believe...). That bridge pickup is indeed in a sweet spot.

 

[Beej]

I've made my own comparison chart before, but because of the scale length differences, they have to be made so that the nut, 12th fret, and G string saddle is aligned. He did the 12th fret and E saddle, which is always well past the bridge witness line in any bass setup. You need the nut and 12th fret in the pic to ensure they are all scaled the same size in the pic. They aren't off by much, but enough that there's no point in using it to compare, especially if one needs it close to accurate for one's build.

 

[JIO]

check this out - not my post ...
Ultimate Pickup Placement Comparison

Yeah, it's surprisingly tricky to get these right. I made this last year by lining up the 12 fret and G string witness line but make no claims of accuracy -- I know positions are in error but I just don't know which ones are off in which direction.
View attachment 4220313

This represents checking one against the other of my basses by measuring from the 12th fret to the bridge pu poles. (all 34" scale)

'66 J - 14.5" to center poles (single-coil)
G&L L2000 - 14" to center of pu (hum-bucker; between upper/lower poles)
Silvertone Hornet/Coral Deluxe Bass (Dano's) - 14.5" to center of lipstick tube (single)
my Teiscobirds - 13.25" to center of DS/BS poles
'64 T-bird II - 14.25" to center of pu (hum-bucker; between upper/lower poles)
'66 P-bass - 11.5" centered between upper/lower pu's
'68 Custom Kraft Bone Buzzer (hollow-body) - 12.5" to center of soap-bar (single)
my SuperB 5'r - 12.5" to center of Delano oval (hum-bucker)

 

[daveman50]

This represents checking one against the other of my basses by measuring from the 12th fret to the bridge pu poles. (all 34" scale)

'66 J - 14.5" to center poles (single-coil)
G&L L2000 - 14" to center of pu (hum-bucker; between upper/lower poles)
Silvertone Hornet/Coral Deluxe Bass (Dano's) - 14.5" to center of lipstick tube (single)
my Teiscobirds - 13.25" to center of DS/BS poles
'64 T-bird II - 14.25" to center of pu (hum-bucker; between upper/lower poles)
'66 P-bass - 11.5" centered between upper/lower pu's
'68 Custom Kraft Bone Buzzer (hollow-body) - 12.5" to center of soap-bar (single)
my SuperB 5'r - 12.5" to center of Delano oval (hum-bucker)

Same method on the Rick yields 12-9/16" from top of 12th fret to center of neck pickup pole piece. Adjusting for the different scale length yields 12.85".

 

[JIO]

Same method on the Rick yields 12-9/16" from top of 12th fret to center of neck pickup pole piece. Adjusting for the different scale length yields 12.85".

So my (Teiscobird) sweet-spot is not a Ric then - somewhere between that and a J