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I had one of those a couple of summers back. I liked the sound a lot but I never got used to the jumbo frets so I sold it off and built a partscaster. The partscaster cost me over twice as much and I think is just marginally better.

Hope you like it!

Duovibe's been on my board for a year. Not sure I can live without the darkness!

Strong veto Kung fu! Love the artwork; my dearly departed grandpa ha a small cattle ranch near Brice. The part of the country is something else, in more ways than one!

5th generation Californian here. Make sure you get inland a little bit too. The Sierra Nevada mountains are nice, but are 4 hours from the coast. I live in Lake Tahoe and it's amazing in September. The stratovolcanoes further north in the Cascades are all breathtaking (Shasta, Jefferson, Hood, Rainer, etc).

All the kool kids got kicked out of San Fransisco by the tech wizards and now live in Oakland, and they're sort of making Oakland into a west coast Brooklyn. Lots of great eats and music there right now (Brick & Mortar and The Independent). I loves me some Doug Fir Lounge in Portland - great stage!

Cool project!

A buzzstop will probably serve you very well. You likely would not need to shim the neck and raise the bridge then. I'm not a huge fan of them because I like that trem, but they do get rid of bridge rattle well.

A lot of guys wrap the bridge posts in electrical tape to minimize the bridge rock. I works pretty well if you don't really use the trem.

I built one a few years back on the OLC pcb. I used shielded wires running from the jacks to the footswitch to squelch oscillation.

Wow - cool guitar! Haven't seen a Mosrite clone before that got the bridge a vibrato correct.

Awesome - can't wait to build it!

The cobbler's children always go barefoot.

lol! 

Wrong, wrong, WRONG!! All but eight of you voted incorrectly. 


You don't know what an Easyvibe is, do you? 

But the more interesting portion is the discussion of scientific method that has come up.

- Burden of proof: If one claims that there IS a difference, then I would really consider the onus to be on them.  Human ears are notoriously unreliable for most people.  Saying "I can hear the difference" is really all the justification one needs to buy guitars and enjoy them, but that is a far cry from any scientific relevance.  I've dealt with a lot of situations where people have heard differences that weren't there and vice verse.

- Control of variables: It is really important to control the variables when making direct comparisons.  Two identical guitars with identical hardware can vary for a variety of reasons, not just the wood.  Known variables are: wood species, weight of the wood, pickup winding, how the nut is cut, how the guitar is setup, mounting position of the bridge, etc.  I totally agree that the same model of guitar with identical hardware can vary greatly, but there is more to it than just the wood.

- Value of experience/expertise: With all respect to Curtis, I wouldn't take somebody's viewpoint at their word simply because they have purchased 700-1000 guitars.  That person may or may not have extensive knowledge of the instruments, but that cannot be assumed.  And it's not a good argument within the context of a scientific debate.  There are plenty of Blues Lawyers that own piles of guitars and know nothing about them.  Curtis isn't one of them, but the point holds.  On the other hand, there are people that are clearly established experts that have become so because they have handled so many instruments over the years.  George Gruhn is a good example.  He's a known expert because he's taken the time to study the minute differences between instruments and knows exactly how things were built.  I've also met other dealers that push a ton of guitars through their stores, but don't really study the instruments; it's just a commodity to them.

I'd add that you actually need a statistically relevant data set. You can't just post audio and graph frequency response of two identical guitars, one with alder and one with ash, and expect an experiment to hold weight. You have to replicate it many time in order to weed out the inconsistencies. And by then, the magic is all gone!

Have you signal tested the circuit? It seems odd that you can get the LEDs to light up without runaway oscillation already occurring. Triple checked resistor values? Maybe a gain resistor is an order of magnitude high in one of the PT op amp stages or something.

Oh, I also have a simple switchable L Pad attenuator that switches between 6 and 12 dB of attenuation. I basically built it for 5E3's. It sounds really good at 6dB, but sounds like crap at 12dB. I find that it's actually a great attenuator for blackface fender circuits - it seems like a lot of times, attenuating 6dB us all you need with those circuits (unless you're the guy playing a twin reverb in a small bar ).

It's pretty money with a deluxe reverb for the bars I typically play. Turn everything to 6 (I like to get 'em cooking), reverb to taste, attenuate 6dB, mic it and point it at my head, BAM - Morgan's in la-la land for the next 4 hours and no one is complaining about the loud guitar player.

Thanks for your advice there, Morgan, sounds like great fun! I should be looking in getting one of those l-Pad attenuators done! Where would I find reliable info / layout for that that you would recommend or have used for yours? Cheers!

Use this: http://www.diyaudioandvideo.com/Calculator/LPad/
Double or triple the power rating of the resistors to be conservative. Use good quality resistors (don't buy the cheap ones on eBay or from Tayda).

The only real issue with this design is typical of all resistive attenuators -  you are using one because you want to drive your amp pretty hard. Driving your amp pretty hard wears down the output tubes and transformers faster than not driving the amp pretty hard. If you look at this particular design, nothing bad can really happen with it. When resistors fail, they typically stop conducting; they don't tend to burn open like a cap sometimes does. So if R1 burns open, the speaker circuit is incomplete and sound stops coming out of it. If R2 burns up, you'll loose attenuation and just have a series CLR in R1 (which will dampen the sound).

Oh, I also have a simple switchable L Pad attenuator that switches between 6 and 12 dB of attenuation. I basically built it for 5E3's. It sounds really good at 6dB, but sounds like crap at 12dB. I find that it's actually a great attenuator for blackface fender circuits - it seems like a lot of times, attenuating 6dB us all you need with those circuits (unless you're the guy playing a twin reverb in a small bar ).

It's pretty money with a deluxe reverb for the bars I typically play. Turn everything to 6 (I like to get 'em cooking), reverb to taste, attenuate 6dB, mic it and point it at my head, BAM - Morgan's in la-la land for the next 4 hours and no one is complaining about the loud guitar player.

I absolutely love power scaling on lower power amps, especially cathode biased amps like 5E3's and 18 waters. They are the cat's pajamas.

But as the circuits get more complicated, so does the scaling.

I've got a 5E7 tweed bandmaster that I incorporated the fixed bias VVR on (quite basically two VVR circuits connected to a dual ganged pot that scales the B+ and bias voltages in tandem). I haven't got it to work yet. First try, the bias voltage wouldn't scale. I pulled it out to find that the bias MOSFET and associated diode had blown. Reinstalled it with new components and immediately blew the B+ MOSFET. I pulled it out again and went over everything with a fine tooth comb. I'm going to try it one more time.

Separately, I've got an amp that it is basically a fender standalone reverb circuit I front if a tweed bassman preamp and phase inverter, with an early 50's era cathode biased 5881 power section (tweed bassman transformers). It's the buggiest amp I've ever built by a mile. Bugs aside, it hates the VVR circuit. I'm scaling the whole amp, which makes the reverb go to mush and oscillate when the voltage gets too low. And taking the reverb out of the circuit, it just doesn't sound right when it is scaled. It sounds like a bad master volume - gets real thin, real quick. I'm this case, I should probably just scale the power section, which is tricky in my experience. You end up with a hot signal coming out of the PI that gets way out if balance with the power section as you scale it down. The trick there is to use a PPIMV to attenuate the PI signal as you scale the power tubes. But then you end up with two controls you have to fiddle with every time you want to back off (infuriating on a dark stage while the sound guy is waiting on your ass).

Anyway, sometimes having an airbrake around is nice in that they are pretty bullet proof and you can move them from amp to amp. And sometimes with larger bottle, fixed bias amps like a JTM 45, it works a bit better to leave the voltages as is and just dump some power on the way to the speakers as needed.

I'm sure scaling can be great in something like that; it just might take a bit of doing!