2006 - Lincoln Chord Organ

Taking a break from guitars, I bring you the Lincoln Chord organ.

Many years ago I became obsessed with the sound of a Harmonium. Unfortunately, they're not exactly easy to come upon, nor cheap when you manage to find one. The next best thing, I discovered was an electric motor powered wind organ.

It's a pretty simple setup, a switch a 12v motor with a fan attached, and some little metal strips (tines) tuned to a certain pitch (Like a tuning fork). The air flows over the tines and produces a metallic reed type sound.
The problem with the chord organ that I have is that it was too noisy. I've rebuilt it a few times, but the fan was always very loud, so there was no way to dampen it without getting into the electrics. Frankly that was something that terrified me. Mains power is scary, when you have no idea on what you're doing.

I got sick of it at some point and loaned it to a friend, who evidently had a similar issue, since it never saw a lot of use. When he gave it back, he told me that the power socket was a bit iffy. When I got it home and plugged it in, I discovered that he wasn't kidding. As soon as the power was switched on, there was aloud bang, sparks and the cable had flown across the kitchen.

Upon further investigation, it was clear that the old power socket on the back of the unit had become very fragile. The metal prongs had somehow managed to touch, which resulted in the shower of sparks. I figured that this would be a good time to sort out the motor control once and for all. So I took a trip to my local electronics dealer and picked up a controller for a light dimmer. I was still deeply paranoid, so it sat in a box for another 3 years, until I decided to give it a go.

Installation of the controller, was a fairly simple affair. Just a matter of identifying what was meant to go where. About a 10 minute job if you don't count the time it took to get my tools together.

The fan controller worked as I thought it would. It gives control to slow the fan down enough, to still produce sound when the keys are pressed, but also quieter than before, to the point where you hardly hear the motor.


Unfortunately, something has happened to a couple of the tines, so they don't produce sound, and a couple of the old felt stoppers were worn, so that the keys didn't close some holes. I made my way to one of the local discount goods shops and picked up a packet of felt for $2 and went to work on the organ.


Under the chord keys, the felt wouldn't stick with craft glue, so I ended up using double sided tape (glue was fine under the regular keys). It took a while to sort out the holes with a scalpel, but it seemed to function much better than before.Still not perfect as a few tines seem to be prevented from vibrating by some unknown hindrance, probably a bit of fluff from the felt. But it works for now, just got to tweak it a little more to get it 100% working.

Chord organs are decent sounding instruments if you can get your hands on one nice and cheap, they add a certain old timey charm or an eerie drone to a song. Don't overlook them as junk shop items.

Epiphone Les Paul: a Mod Story

My Les Paul hasn't seen much action since I bought it. A cheap guitar that I never had professionally setup.
Playing it was like fighting it. The action was all wrong, the intonation was impossible and the neck was bowed.
I hadn't had the confidence to have a crack at it myself as getting information from the net isn't always reliable.
A couple of months ago I bought a book on setting up guitars. It explained clearly and with pictures what needed to be done. Also a few tools that were recommended that I hadn't considered.
One of them being an 18" straight edge. I'd looked around online and they weren't cheap.
I wasn't about to spend $40 on what is essentially an 18" ruler.

From one of my other projects, I had some leftover U shaped aluminium rail, which was a little longer than needed. After testing how straight it was against a known surface, I trimmed the excess and set to work on the Les Paul.

I loosened it off before tightening, using the DIY straight edge to ensure that I was on track.
Gradually tightening the truss rod and checking with the straight edge, I could see that the bow of the neck was becoming less pronounced. At each adjustment I'd play each string along the neck and double checking the trouble spots that I'd known about from before.

Pretty quickly it was obvious that the playability was improving. I'd adjusted the bridge for a fairly low action, so when I hit the strings hard there's a bit of buzz on the neck, but it's not audible through the pickups. I need the low action on this guitar as the neck is quite fat and I have fairly small hands.

The next thing that needed attention was the intonation. I'd had a lot of trouble with intonation on this guitar, to the point where the saddles would not travel far enough in either direction to compensate. Some of this was no doubt due to the action and lack of setup, but it was also a common problem with the cheap bridge used on a lot of Epiphone guitars. I'd added a Bigsby recently and figured that having a roller bridge wouldn't hurt any, so I picked up a Wilkinson clone for around $20 online, which turned out to be the best thing I could have done.
The design of the bridge is such that there is a lot of room backward and forward to adjust, as well as being able to flip its saddles without much effort. Intonation was breeze and the guitar was setup in maybe half an hour.

When I installed the Bigsby, I used a Vibramate to mount it in the existing post holes. The posts came out with little effort (I only needed to use my fingers), which I thought might be a problem later on. during the setup, one side of the Vibramate had lifted out of the body. I wedged it back in, but this doesn't seem like its going to be the end of that issue. I left it overnight, so it's holding for the time being.

The Bigsby design has two design flaws in my opinion. One, the way that the strings are mounted and the other is the limited movement of the vibrato bar. It doesn't allow the bar to move over the strings and sits just next to the high E. This means an adjustment of technique, by either grabbing it with my pinky, or pausing on a chord to move the bar. On my other guitars I usually have the bar centered over the strings and Hold it with three fingers while playing. I'm probably going to grind the stopper off the Bigsby to retain that freedom of movement.

You might recall that I scored some pickups from my friend's Gretsch. One of these I modified to fit in the neck position of the Les Paul. The biggest delay in putting this guitar back together was that I had not been lucky with trying to make a pickup ring to suit. It's not a standard sized mini humbucker, so there aren't any off the shelf solutions going around. What I ended up doing was modifying a standard humbucker ring to hold it on place. Now I have the same problem with this pickup as I do with the Filtertron on my Surfcaster. The string width is different. On Gretsch guitars the spacing is a little wider than Gibson spacing (which the Les Paul and Surfcaster use). This is no big deal on the center strings, but the E strings fall inside of the pole pieces and not directly over the op of them as intended.

I never thought it would make much of a difference. But it does. It makes a huge difference. The inner strings have great clarity and impact, where the outer strings are dull and lackluster. The pole pieces can be adjusted, but it only makes the string louder without the characteristic tone of the pickup.

One way of compensating for this is to put the pickup on an angle, so that the string almost sits in middle of the pair of poles. At this point I haven't managed to get quite enough of an angle and will need to extract the pickup and trim some more metal off the pickup casing.

The Gretsch pickup has a nice piano like tone, which really changes the character of the guitar. Coupled with the Semour Duncan P-Rail and the active EQ, I really do have a lot of tone options available on this guitar.
It's not quite finished, but I'm happy with the sound and feel, so it will likely be some time before I attend to the remaining issues.


So many guitars. So little time!

Hiccups. Computers, Dust. Damp. Crackle and Pop.

My current home is a dank, dark, damp inner city cave.
No good for electrical contacts of any sort.
I can't have my gear up against one wall of the building if I don't want to constantly be cleaning pots, jacks and tube sockets. It's a pretty tedious game.

Anyway I thought I had all of the mechanical stuff licked and went to do some demos.
My first project was going to be a combination of reverb shootout between a Digiverb and my Princeton, which would also be testing my isolation cabinet and the line out of the Weber Z-Matcher.

Everything sounded great through the headphones.
I was getting a nice clear signal. No crackles etc...

Played for hours.

Thinking I'd do some editing I booted up my compute and started listening to the tracks.
What I met with, was the horror of my PC not keeping up with recording 5 tracks of audio and one plugin.
The audio was stuttering and jumbled and generally horrible.

It seems that my gutsy old PC is suffering a little from background fatigue.
Meaning, there's so much crap coming on at boot up that the quad core just isn't coping.
Also it may be an indication that one of my hard drives is on its way out.

The session has been scrapped, so my demos are going to be delayed somewhat.
Hopefully the weekend frees up some time to make noise.

As always. I'll keep you posted.

2011 - Weber Z-Matcher

Weber Z-Matcher 50W version

I've had this red box for a few months now, and have used it exclusively with my Fender Princeton Reverb RI and Epiphone 12" cab, which resided in my isolation cab.

The Princeton is engineered for a nominal load of 8 Ohms, but the Epiphone cab is 16 ohms. Everything I've read about the subject is that the amp down't handle the higher load very well, and that it would be better to run two 8 om speakers in parralell(gets you 4 ohms), rather than an 8 and 16. It's all to do with math and ratio's and running mismatched loads is a no no. Sure it's going to get you a load of 6 ohms or so, but since one speaker has less resistance, most of the power will go through there and will naturally be louder than the other as a matter of course. Also this doesn't fit the ratio that the amp requires.
First I tried using a resistive dummy load to match everything up, but since a speaker doesn't have a fixed resistance (due to the combination of frequency and inductance of the voice coil), the results weren't exactly pleasing.

I'd read all about inductive loads being the way to go, and pretty much the only one that I could find with any reviews, was the one from Weber. The manufacturers of fine speakers for guitar amps.
After a lot of deliberation and indecision, I decided that having a variable inductive load would be the way to go. so I bought the 50w Z-Matcher.

The purchasing process is a little odd, it's all via email and can take some time to get your quote back, but the staff were helpful when arranging the postage. But the transaction itself was done via Paypal and they were happy to send it Via USPS when asked. Weber build all of their stuff to order, so there's a bit of a waiting period, but being in Australia, I've gotten used to waiting for my stuff to arrive. Hey, if I can't get what I want locally (or locally at a competitive rate), then I have to go offshore for the products I want/need.

They estimated up to six weeks for assembly, but it was at my door in less than a month (not bad in my opinion). Anyway, back to the box. It came in a simple postage container wrapped in paper and bubble wrap. It's quite a heavy unit, so I delayed taking it home for a few days.
There's no manual to speak of, but there's no need if you're familiar with the basics of speaker matching (all us amplified guitars and bassists should be!).

Front Panel:
amp in
amp impedance (2-16 ohms)
speaker impedance (2-16 ohms
speaker out

Rear Panel
Line Volume
Line out - Balance
Line out - unbalanced
Parallel Speaker out

It was put to work matching the Epiphone Cab in the isolation box.
The first test I ran it through was the line out. Honestly I wasn't really impressed. Clean guitar was fine, but overdriven just sounded fizzy (pretty much like any amp with line out ever).
But hey, I wasn't exactly expecting a miracle there.

The next test I did was mic (Shure SM57) up the speaker and A/B that with the line out. Guess what? The mic even carelessly placed, sounded a lot nicer than the line out. I left it like this for a few months, and just playing with it when I had a couple of spare hours. After a while I noticed a bit of a weird distortion when using reverb on the Princeton. Especially if I was driving the reverb hard. I figured it was either a dodgy cable or maybe a quirk of the speaker cab inside a fairly small volume of air (there's a lot going on in an iso cab with a large speaker. Standing waves and other funky things can send voltage back to the transformer of the amp if you're unlucky). Also my headphones are a little rattly in some frequencies.

Upon further investigation, it turned out not to be a problem with anything mentioned above, and I haven't got definitive proof yet, but I have a hypothesis which makes sense (need to find an engineer wiling to experiment).

I decided to test the whole rig outside of the cabinet and directly with my ears, reducing the variables where interference could occur(cab, mic, lead, mixer, earphones). First up, I tested the amp by itself on a rubber mat to damp vibrations into the floor. Aside from making the house rattle when it was barely past two on the dial, the amp sounded as it should with the reverb cranked).

The next thing I did was to put the Z-Matcher between the amp and it's stock 10" speaker and set for 8 ohms per side. The distortion came back. Next I plugged in the 16 ohm cab. Again, fine on straight guitar signal, weird distortion with reverb. Last up I placed the speakers in parallel. The 16 ohm cab directly into the amp, and the 8 ohm stock speaker via the Z-Matcher (the amp side of the Z-Matcher was set to 16 ohms in order to present and 8 ohm overall load to the amp). As I'd already had a suspicion that the distortion was happening inside the Z-Matcher, it was no surprise to find that I had the distortion coming through the 10" speaker and not the 12".

The Z-Matcher works flawlessly with any signal presented to it as long as there is no reverb in the mix.
What I think is happening is that there are weird things happening inside the inductors of the Z-Matcher, due to the complex reflections generated by the reverb.

Reverb adds to those complexities and since the coils of the Z-Matcher aren't on the move as they would be with a speaker/magnet combination, there is a bit of a inductive choke effect going on and the result is the distortion that I'm hearing. It's subtle and I don't think that it would matter much in a band setting. The sound does stand out for me now as I'm aware of it. But I don't think it's a deal breaker on the Z-Matcher. It's just a quirk of electromagnetism and I can live with it as the unit serves it's purpose.

Reader input

Ok, so I do the update thing whenever I get a new bit of gear or am reminiscing about the good old days, lamenting being a dunderhead or whatever.


But tell me dear reader, what would you like to see on these pages?
Sound files
Videos
More photo's
Tutorials

I've recently passed the 11,000 view mark, but I've only received a handful of comments.
So it seems that I'm either doing something right, or doing something wrong.

Come on kids.
Let me have it!

Repairs: Ibanez FL9 Flanger - Not quite!

Oh man. I went to play with it last night.
The LFO problem is back.

Oddly though, the ability to do a parked flange is pretty nifty.
Kinda like parking your wah, but with a time based effect instead!

Repairs: Ibanez FL9 Flanger

Since I don't get much time to play guitar these days and when I do, it's generally just guitar and amp. My FX don't get used too often, and the least often used of my FX would have to be my Ibanez FL9 Flanger. Generally I don't havemuch use for flanging effects. It's fun and all, but I prefer to use it sparingly. If I'm going to use a modulated effect, it's more likely that I'll use a phaser. Just personal preference.

Because of this, my FL9 sat in a drawer for the best part of a year. It's an old pedal (over 25 years) and the last time I went to use it, it just passed a clean tone. The pedal wasn't toally broken, the delay chip was still working as there as a bit of a flange sound when twiddling the controls. Upon opening it up, some of the jooints looked cold. So I proceeded to re-solder everything on the board. No go. It took a  while to track down the schematic (didn't end up using it), but I'd read a snippet from one forum about replacing old electrolytic caps, so i figured that i'd give it a try. I went over the board and documented everything electrolytic.

There were two caps near the middle of the board which weren't coloured blue like the rest (they were orange), so I decided to replace them first and give it a test (I'd seen a similar arrangement on a synth I'd built). My hunch was right, they were there to control the LFO rate. The LFO was working again, but the effect was very subtle. Not at all like I remembered.

Fortunately the board has three trim pots for adjusting various biases. Ignore the middle one, it's there to bias a transistor and the factory setting is just right to avoid unwanted and unpleasant clipping. The trim pot closes to the middle controls feedback and the one further away controls depth. With these two trim pots you can get the pedal to self oscillate. Particularly with the first one. It's not a sound I'd want all the time, so I've set it up to kick in at about 70% maximum on the front panel feedback knob. The mod is safe and easy to do. You won't even need to take the board out to do it. While increasing the feedback makes the flanger more prominent, it still falls short of being a true "jet" flanger. Still it is nice to have in the tool kit.

FL9 Service Manual Page 1

FL9 Service Manual Page 2 (Schematic)

FL9 Service Manual Page 3 (Trouble Shooting)

FL9 Service Manual Page 4 (PCB Layout) - LFO Caps Highlighted w/red box.

Re-Repair & sound sample.