ODS build from SF Bassman 70

[guitardude57]

Howdy,

Can anyone point me to the right spot where Normster had posted info on a SF Bassman into ODS conversion? BOM and tweak notes? His site is a little skinny on info/function.

I picked up a late 70's Bassman 70 in good shape for 300 bucks. I think the PS should handle the mod well, and will build the appropriate unit considering power tranny. I have a couple old output trannies for some flex, but the original Fender in there should be fine too.
Money is pretty thin these days, so will re-use as many parts as possible.

Who makes the complete turretboard sets, including relay boards?

I like the jazz guys' tones, a great clean, and a nice singing crunch for the blues, and rock tones.
LP, Strat, and PRS with P100's are the guitars used, so I believe there will be some tweaking to get this build to dial in to these guitars


I ran into Normster's detailed mod info once, and after a hard drive crash and subsequent full reinstall on another drive last nite, can't find it.
I am not buying anymore PC/laptops...............(especially Toshiba
This thing has been nothing but trouble the 7 years I've had it.......)
Must have been the lightning strike that came in on the phone line....LOL.

Comments/suggestions welcome Thanks, Mike

[Structo]

I did a search and didn't really find what you are after.

But, if you want to build a 2 x 6L6 ODS, you can go by the D'lite layout if you don't want all the bells and whistles or you can use the ODS #124 layout if you want all the switches and stuff.

Since your bassman is a 2 x 6L6 amp, I think if you were to use the Tweaked version of the D'lite, that will work out.
The values on this layout get the amp closer to Dumble using 6L6 tubes.

I don't know anybody that is selling the boards but they really aren't hard to make.
There are some board layouts in the file section.
Hoffman carries the G10 Garolite and eyelets.

Ampdoc1 sells the relay and relay PS boards.


Attached is my version of the Tweaked layout, showing the mid cap switch, it allows switching between the .01uF and .05uF mid cap.
This helps with single coils to fatten them up or you can use the .01uF position for humbuckers.

The PI balancing trimmer pot helps to get nice overtones and harmonic bliss when adjusted properly.

Also I included the local feedback loop switch on V1.
I label it RAW and SMOOTH, when the loop is out of the circuit the tone and feel is a bit more raw or loose sounding, when the loop is in, it smooths the tone down a bit.
A subtle effect.

In this version I also change the way the Standby switch is wired.
The first filter caps are powered up when the power switch is thrown, this allows them to charge and not slam the rectifier too hard when the standby switch is flipped.
This also shows a choke being used, I like that as well but you can use a 10 w resistor there with a 300R-500R value instead of the choke.

[Bob-I]

I have the layouts for 2 Bassman D-Clones, I don't know if these are Norm's or someone elses but I pulled them from this site so I'm sure the owner won't mind them being posted again. One is an HRM and one is non-HRM. Neither of these have relays, just switches on the face plate. Easy enough to change to relays, just take a relay supply and boards from another layout and sub in for the switches.

Norm fabricates his own boards as do I. It's easy to do with a drill press, easy to do without as well but more time consuming. If you need help just ask.

[M Fowler]

I did a search and it showed this Bassman D-clone?

[Structo]

Holy cow!
That's pretty cool!

Got the loop and everything.

[guitardude57]

Thanx for the layouts guys, you are the best!
I am planning on doing the relays, and can make the boards.

I had seen someones' turret board sets for 40 bucks or there-abouts, and can't find that anymore either. I find that a reasonable amount, to save some time. I am hoping that there are some good parts to re-use in there, to save some $ too.

I am planning on a move back to Denver in a couple months, so I have enough tools and equipment to do some building, not packed up. No drill press yet though.

Mark, I think that was the one I had looked at before, and couldn't save.......due to computer probs. Which one have you built?

I will not do the reverb, and if I have the space will put the D-lator inside. Will be tight, but sometimes we like tight..............

Thanks again. Mike

[M Fowler]

Mike,

I am in the middle of the 100w BM HRM.

Also a 30w ODS version using some left over DC-30 PT, choke and OT for a 6V6 output section. Fitting components to the boards yesterday. I'm using Brownnote layout. I will be using tube rectifier so that leaves me one octal hole extra, so may add a 6SN7 octal tube for reverb or just leave the reverb out for now.

I like to mix things up and not go with traditional clones.

Mark

[BobW]

Here's yet another layout: I leveraged Bob-I's layout on this one. thanks Bob

https://tubeamparchive.com/viewtopic.ph ... highlight=

[guitardude57]

Hey Mark,

It sounds like your bench is pretty busy these days!
I can't wait to relocate and have a good shop space myself. I have been doing my tech work on the livingroom coffee table the last year........it really sucks.

Bob W.

I really like the Rev D stuff you posted. It should be perfect for my B-70.

Any chance of a BOM for this?

Maybe add FX loop in addition. Would be cool if room allows, D-lator type circuit built in there. I do use a nice FX rack with Bradshaw type switcher. Would be great to incorporate this new build into my set up.

Not concerned with exact clone thing. The circuit and mojo, yes.

I would also like to find some front and rear metal panels to go over the existing chassis. Does anybody silk screen these? That way I would just match the control and switch holes etc, on the chassis and cover up the originals.

Thanx, Mike

[Structo]

Depending how fancy you want to get on the faceplates, you can have custom engraved ones made with your design.
They are at a minimum around $75 each.

Or like what I did is paint the panel gloss black then used my Brother label maker using black tape with white lettering.
Kind of a prototype look if you will, but I just could not cough up $150 for two face plates.

At first I was going to make some waterslide decals and apply clear coat over them.
But when I tried applying a decal, it was too dark to show up against the black panel.

So I went with the labels on this one.
Brother sells many colors of tape and lettering.

What another member does is design a full sized faceplate then has it printed out on adhesive paper, then clear coated the ink so it would be more durable.

I may try that.

I think I would take my design to a print shop and have it printed on a good laser printer because my inkjet printer does not print black that is black enough to look good, sort of like a dark grey.

[BobW]

GD57, I don't have a BOM but the Rev E layout is more current (page 2 link), and in VISIO format.

[Structo]

There is an incomplete BOM around here somewhere.

I found some board layouts.

[Structo]

More

[guitardude57]

Structo,

I think the idea of the print shop is a good one. How about this idea;

Make an appropriate panel set out of some thin aluminum (1/16 inch or so thick) the right length, and a 1/2 inch taller, so that you could bend a lip across the top and bottom 1/4 inch, to wrap over the exposed chassis. Once placed in the cabinet, you would not know it was a separate panel from the chassis. The control pot nuts, input jack nuts, and switch screws would hold it in place. Thin material shouldn't hamper pot shaft length much.

Match up all the holes for controls etc on these panels.

Take these and your Visio or other full size drawing to a print shop and have them make a screen for them.

You may ask how they would mount these panels (as they are Pre-bent by you) on their screen printing rig.....maybe make a holding jig out of a ripped 2X4 for them ...........to make it easier for them to screen and roll the ink.

Hmmmm raised ink.........good. Just let it gas off, and dry well before attaching to chassis.

I'm sure they have different types of inks, find out what would best bond to the acrylic black paint you would put on the panels prior to their handy work. As long as your panel, holes and drawings line up it would look awesome and permanent.

Look around your area, might find someone to do it cheaper than $100

Bob, I don't have Visio, but will look around, to see if I can dig up the program somewhere.

Thanks for the assistance guys. Mike

[Structo]

I do know that making a silk screen is pretty involved and expensive unless you do it yourself.
I know a couple guys that are starting a new line of guitars.
He made a screen to print the logo on the headstock and he told me it was a pain in the ass but since they were going to use it over and over it worked best for them.
He considered the alternatives such as waterslide decals and the like but felt the silk screen was the best for his app.

Now I don't have any experience with screening but to me the trouble would be the lettering and getting all the pot increments (dots around the knob) right.
That being said, a well screen panel does look really good.
The chassis I have was screened over the black powder coat and it looks great.
But for a one off amp it may be a bit expensive.

The best way to do the chassis and faceplate would be to get the faceplate done, regardless if it is an adhesive or thin aluminum panel, then use that as your drilling template.
That way you would be sure to get the pot holes and everything perfectly lined up.

Trying to mark or measure holes that are already drilled into the chassis to a faceplate is a bit challenging but can be done but it is easier to do it the other way around.

As for the material, lots of guys use the thin aluminum panels that are laser engraved like BNP Lasers make.
http://www.bnplasers.com/index.html

Depending on the way the cabinet is I don't think you really need to bend the top and bottom over the chassis because on my amp at least, the face butts up against the cab and it doesn't matter if the top or bottom edge wraps around because it isn't visible.