TubeScreamer+ Project - Part 3

CAPACITOR MOD

Before we get on to the mounting work, I thought I might follow up on one of the mods I referred to in the previous post. The folks at DIY Effects offered a suggestion of changing out one of the capacitors to provide additional low-end on the output signal. I liked the idea (and it's really a very simple mod), but I was concerned about losing the 'original' Tube Screamer sound. So as a compromise, I did both. By soldering the leads of both caps together, and connecting the other two leads to a switch, I could select between the original sound, and the extra low-end. Here's what that looks like (the switch is connected to the red, yellow, and black wires underneath the board).

After the photo was taken, I dropped a small amount of hot glue on the capacitor leads to provide a little stability, and to ensure they never touch.

PREPARING THE ENCLOSURE

I picked up this enclosure from Pedal Parts Plus. They have a good selection of enclosures (all cast aluminum), but more than that, they have made ordering the finish a breeze. You just add the case, and a paint charge to your shopping cart, then add a finish to the shopping cart. They have a few finish pricing models (based upon the complexity/cost of the finish), so you do have to make sure the finish charge you add to your cart is appropriate for the finish type that you add. I ordered this on a Sunday night. Monday morning I received an e-mail saying that the case shipped, and had a tracking number. It arrived on Friday.

Step 1 is to mark the holes. There's nothing too complicated here: just draw the lines, mark your holes, then, using a punch or nail, tap a dent in the center of each hole to keep your drill bit from 'walking' along the surface as you're starting to drill.

WARNINGS

A few items are worth mentioning at this stage. DIY provides a diagram of where the holes should go, including diameters. It's a 1-page PDF file. The first time I printed this out, the dimensions all lined up perfectly on the box. The second time I printed it (on a different printer), the output was slightly smaller than the enclosure surface. To be safe, use the measurements; don't rely on the size of the printed output as an accurate guide. Also when you look at the diagram, the top face appears as you would expect: the controls are at the top, and the foot switch is at the bottom. As you look at the front face, however, it is actually upside down, relative to how the pedal sits. It shows the in/out jacks at the top, when in fact, they should be at the bottom. There is even the word "TOP" printed on what should be the bottom, further inviting you to drill holes in the wrong place. Check, recheck, then check one more time.

Once the holes are marked, it's time to drill some guide holes. I like a 1/8" drill bit for this. It's large enough to force the step drill bit in the right direction, but small enough that if the bit shifts, you can recover with some manual effort. (The cases are cast aluminum, The nature of casting metals is that some areas will be more dense, and some less. As a result, even if you properly tap the holes as described above, the bit can still shift as you are drilling.)

After drilling guide holes, it's time for the actual holes. All of the hole diameters specified in the enclosure prep guide provided by DIY Effects matched up nicely with the sizes of the actual components, but you can't undrill a hole, so be sure to recheck the actual components before you start. If in doubt, since we're using a step drill bit, make the hole a little smaller, and have the components on hand to check the fit. To keep myself from drilling the holes too large, I placed a piece of tape above the final step. This gives a really good visual cue to help you know where to stop. One last tip: if you have access to a drill press, that makes life much easier. You can do it with a regular drill, but the press helps with straightness, and preventing some of the issues with the bit moving above.

Once your holes are drilled, you have a box ready for mounting the board and components. If you go with the DIY Effects plans, you'll notice some changes to the original layout. I added the second switch above the original for the capacitor mod, and I moved the hole for the power indicator LED up a little to give the second switch some extra room.

Mounting the components was pretty simple, though I've left out an important step. It's a good idea, before you get to this stage, to set the board up on a bench and test it out. There are a number of steps at which a mistake could happen:a cold solder joint, a drop of solder touching an unintended contact, a bad component, etc. Troubleshooting the pedal in the case is no fun, and with this design, getting the board in and out means soldering, and desoldering the 9v and ground wires to the power receptacle each time. As it happens, with this one, I discovered that the power receptacle has a short in it. So, my final assembly will have to wait until I get a replacement.

PART 1 ~ PART 2 ~ PART 3 ~ PART 4 ~ PART 5

TubeScreamer+ Project - Part 2

I'm a few hours into the project. Below is the current progress. I discovered that I am short one diode so there will be some delay (no pun intended). Image below shows the components, and the stomp switch.

CLIPPING CIRCUITS

Here, I've highlighted the clipping circuits. Circled in red is the standard clipping circuit found in the original TS-808. It's basically just a set of diodes reversed. One mod to this is for asymmetric clipping, which is achieved by adding a third diode. I opted to keep this circuit the same as the original, so instead of adding the third diode, I just ran a jumper in its place. The section surrounded by blue is an option for clipping using two LEDs. Since the design supports only two clipping mods, I opted out of this one. In green is a third option, using two MOSFET transistors and two diodes.

CAPACITOR MOD

Looking closely on the lower right, there is a spot for a capacitor with nothing in it (C11, upside-down). There is another optional mod that allows for changing out this capacitor with others in order to boost the lower frequencies. DIY Effects offered three possible replacements for the stock capacitor. This will be my second mod, but before I decide which capacitor to put into place, I need to hear them. I can't play through the unit without the second missing diode, so this will have to wait.

Next up will be drilling the case so I can get the pots, jacks, and switches mounted.

PART 1 ~ PART 2 ~ PART 3 ~ PART 4 ~ PART 5

TubeScreamer+ Project - Part 1

PROCUREMENT

As I was jamming with my buddy Simon (Check out his blog for other cool guitar projects), He fired up his Tubescreamer clone from DIY Effects. It was one of those 'THAT'S IT! THAT'S THE SOUND!' moments. So, it's off to the electronics store (and DIY Effects for the circuitboard). So, this is part one of my journey to build my own TS clone. It's modeled after the Ibanez TS808 (the original), but I'm introducing two additional mods (hence the "+" in the name) that will provide additional tone and clipping options without sacrificing the original sound. Everything has arrived, so tonight we start assembly.

The original TS808 was green, so I opted for a green case as a sort of nod to Ibanez. That said, the layout of the enclosure and the mods will make this a very different pedal, while still keeping the sound close to the original.

Update: 5/7/2016

Since I ran into a defective part and had to re-order, I thought it might be useful to add some comments on ordering parts. DIY refers to a "project" available at Mouser where you can just type in the project name, and get a shopping cart filled with everything except the potentiometers, knobs, and case. Unfortunately, that project is a bit dated, and not everything is available any longer. Here are some notes that might help:

• Part numbers for the transistors, IC socket, and LEDs have changed, but replacements are available (I took the replacement diodes from Mouser, and went to DigiKey for the others.) Replacement part numbers from Digikey are:
• Transistors: MPSA18CS-ND
• IC socket: AE9986-ND
• Mouser no longer carries the 1N34A diodes. If you're not doing the diode/transistor clipping mod, this is no big deal (it's the only place they are used). If you do want that clipping mod, you can get the diodes from DigiKey.com (VERY expensive), or Pedal Parts Plus (much more reasonable).
• You can get the footswitch , potentiometers, knobs, etc. from Mammoth Electronics. They have a great site that makes finding exactly the part you need really easy.
• When you start going to multiple sites, you're going to find that you get soaked on shipping. Most places are around $8.00/order for USPS. Make sure you get everything you need from as few places as possible.
• You can also get a lot of the parts from Pedal Parts Plus. Their selection is not quite as good, but the prices are really reasonable, and turnaround is quick. You might have to do some research to cross-reference part numbers.

PART 1 ~ PART 2 ~ PART 3 ~ PART 4 ~ PART 5

1967 Fender Deluxe Reverb Restoration Project - Part 1

History

I received the amp chassis and electronics from my late brother-in-law, Phil, back in the mid-1990's. I have no idea where he got it. All it had was the chassis, faceplate, circuit board with electronics, and knobs. No tubes, cabinet, speaker, etc. At the time, I built a decent cabinet (it's lasted this long), hung a 12" Peavy speaker off of it, plugged in some tubes, and off I went. Unfortunately, as the amp warmed up, there was a low hum, and the gain dropped way down, to the point where it couldn't really be played. It sat under the stairs up until October, when I was discussing with my train buddy, Simon, that I had this amp, and it was not in the best shape. He asked if I knew what the amp was worth, and I said I didn't know. He suggested, behind that sheepish grin, looking up some auctions for the same amp on eBay, and let him know what I found out. He also suggested a cap job. So yeah, looked it up and I know what I've got sitting here, now. Did the cap job back in October, and the difference was amazing. It sounds so beautiful, that I got bit by the bug, and now I have to restore it. So this is just a short page describing the journey from coal to diamond.

Issues identified:

•     cabinet is missing
•     speaker is missing
•     capacitors are not functioning
•     knobs are chewed up
•     faceplate has silver paint overspray
•     footswitch is missing
•     reverb tank is misisng
•     No tubes
•     One resistor is out of spec
•     power cord is missing

Starting Point (~1994)

Ths is what I received. I am pretty sure all of the internal parts are original, possibly with the exception of the bright blue capactor on the right 1/3 of the circuit board. Look close on the left side of the faceplate, and you can see the silver overspray on the plate and on some of the knobs where some previous owner likely tried to spray the gill cloth silver (*sigh*).

Cabinet #1 (~1995)

So here's the cabinet I built in the mid 90s. It's a basic pine box with 3/8" ply front and back, covered with vinyl, and chorome corners. It doesn't look great, but it was better than nothing, and it is really solid - no wobbling, squeaks, or anything after roughly 20 years.

Capacitor Repair (2015)

After opening the cover, it was clear that this thing still had the original capacitors. So, I ordered a kit online (ran about $25 as I recall), and swapped them out. This made a world of difference in the sound, and stability over time. The circuit board is not shown, but I replaced a number of capacitors there, also.

Dating the Amp

One of the objectives of the restoration is to try to get the amp back in its original state (within reason). So before I go further with purchasing replacement parts, it's probably a good time to try to date the amp. The definitive answer is not available, as the original cabinet is missing, and along with it, the label on the inside with the manufacture date. No numbers on the chassis are of any help either. I'm confident it's from the 60s, as it's a blackface, had the cardboard circuitboard, and contains the blue capacitors that were used by Fender before CBS purchased the company. The next attempt was to look at images of similar (and dated) amps on the Internet, which gets me as close as 1965 - 1968. Then, I started looking at actual components. It turns out, many electronic components are stamped with a code that is defined by the EIA, and contains date information. One of the transformers came back with a manufacture date of 1967. Looking at the aging of the parts, it did not seem to be a later replacement, which would put the amp in 1967 or 1968. Since silverfaces emerged in 1968, I'll be going with the 1967 date.

Cabinet #2 (2016)

My awesome wife hooked me up with a Mojotone cabinet that I used to replace the old homebrew cabinet. The folks at Mojotone put a good deal of work into making this right. The tolex is perfect - no bumps, folds, etc., and the head fits into the opening perfectly. It came without straps to mount the chassis, so that's next on the list. I cleaned up the worst of the silver paint on the blackface plate. I used a Magic sponge from Arm & Hammer - it took the spray off without damaging the paint.

Adornments (2016)

In order to cart the amp around and play it, I needed to mount the chassis. You can see the mounting straps on the top. I also decided to pick up a period logo and fix to the grill. Finally, I did some rewiring of the input power to ground the chassis properly.

Other Posts in this series: PART 2 ~ PART 3.

Telecaster Clone Build

History

About 30 years ago, I took an attempt at building my own electric guitar. Before we go any further, (spoiler alert) it was a spectacular failure. The approach I took was to make the entire guitar from scratch - big mistake. About 10 years later, I refinished an Ibanez guitar using spray paint and polyurathane (with a brush). The finish was pretty bad looking, and I learned that a brush is no way to finish a guitar. So, attempt #2 took place in 2003. This time I purchased a kit and set off to work.

Starting Point (2003)

The kit came from Saga (a well-known kit manufacturer). It included the body, neck (the adjustment screw, and fretboard were already attached), and all of the chrome hardware. The neck had a slight twist in it (looking down the fretboard, the entire neck seemed to twist to the left) which was a little concerning, but I had hopes that a little tuning on the adjustment knob in the neck might help. I decided I wanted something in a dark green with gold hardware, so I dumped all of the existing hardware in the trash and went to work on the internet locating gold replacements for everything.

Body

The body is basswood with a poly coating over the top. I planned on having no pick guard - just the painted wood and components. I gave it three coats of primer, followed by 6 coats of color, and 5 coats of clear. The primer and color were auto paint. I've used that in the past on a truck I once owned, and was really impressed with the hardness and durability of the auto paint versus the laquer you buy for general home use. The clear was a durable laquer. After each coat, I sanded it with 1000-grid sandpaper. After the final clear coat, I sanded with 1000-grit, followed by 1500-grit, and finally rubbing compound. The shine wasn't what you would find in the store, but it had a beautiful lustre. Once dry (or so I thought - more on this point later), I soldered all of the components on, and mounted everything to the body.

Neck and Head

The neck is maple with a rosewood fingerboard. The head was unfinished, so I got to add a little of my own design. I finally settled on a recurve design. I took an old CD, and one of my daughter's toys to create the arcs. It ended up looking more like a bird than I thought it would - a point about which I am less than enthusiastic, but it's definitely my own design. I used the same primer/color/clear paint & process on the front of the head. The neck and back of the head received only a few coats of clearcoat (of course, no paint at all on the fretboard). I selected a coat of arms for the logo on the head, another design choice that I didn't really care for once it was done. The sound is beautiful. It has that twang that separates telecasters, is well balanced, and is a real joy to play. It especially sounds amazing through my Deluxe Reverb. The twist in the neck disappeared over time, as well. I'm not really sure if it was the adjustment screw, or just having the tension of strings pulling on it.

2015 Refinish

A few weeks after the original build in 2003, I bought a gig bag for the guitar, and thinking the finish was completely dry, started storing it in the bag. Some months later, I noticed an odd reflection down at the bottom of the body. A closer look revealed that the texture of the gig bag had become impressed in the lacquer clear coat. I also got tired of the coat of arms logo, so it was time for action. I tried buffing it back out with rubbing compound, but the indentations were entirely too deep. So, off to work sanding. I took it down to the color coats, and started to build it back up from there. The body needed a small bit of additional color - fortunately, I had the last of the original can of paint left over. I also stripped the head, decal and all, down to the paint, and built that back up. This time, I settled on something as simple as my signature, using a gold metallic paint pen.

This time, I built some guitar wall hangars, and the tele has been hanging for a couple of months on the wall, rather than in the bag.

Setup

Playing for over 30 years, I have a pretty good grasp of tuning. I never did take the time to learn how to properly set up a guitar, however. I recently found an old video by Mark Arnquist from 1986 explaining the process. After going through that video, I set up the guitar properly, and it plays as well as any guitar I've ever played.