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I don't know about comparisons but my general advice is you get what you pay for with Tayda. I have seen numerous builds gone wrong that came down to bad Tayda components (although many of those were bad charge pumps). You'd probably have to get down and dirty with a scope or measure noise levels with a wave form feed to get a real accurate idea (and across multiple devices).

One suggestion I've heard is that Tayda sources some off-spec components which is why they are so cheap. Have no idea if it's true or not. But, I don't buy any active devices from them. Pots, sure. And tons of IC sockets and LEDs.

It's likely a grounding or power issue. Are you sure you wired your jacks and DC properly?

Ha ha, I fooled you guys. I totally bought one!

Anyway, I haven't fired it up yet but here are a couple of assembly tips:

- Follow the diagrams on the pdf I posted. They are pretty accurate.
- The diagrams list the screw lengths so follow those. It's easy to get the 10mm and 12mm confused so keep a ruler handy.
- Don't over-tighten the wheel attachments. The PVC offset spacers will crack if you do it too tight. Moderate turns...not cranked down.
- Before you screw the aluminum extrusions together, put 4 of the t-nuts in the back (two for the acrylic stands and two for the control panel) and two in front (for the front stands). Otherwise you will have to disassemble the frame to put them in (this is not on the assembly instructions).
- The belt guide that attaches to the steppers has two insert screws to tighten...not one!
- The button for my controller board has a round hole. The switch has a larger rectanguler protrusion. Maybe I am a moron but I don't know how that is supposed to work. I used an old game controller button with a spring instead.
- Strain relief on the cables is probably a good idea.

Glad I didn't buy one of these because it would have taken me almost 4 hours to put together including re-doing some work.

They will all work about the same. In the charge pump design one electro supplies the pump with a constant voltage and the other decouples the output from ground to supply the circuit. The difference is using 10uF, 22uF or 47uF should not have much impact on the voltage output (I typically use 10uF and the Klon even uses 1uF). Using the suggested low-ESR type probably has more influence on the output that the particular value chosen for the two caps.

Many op-amps are designed for bi-polar supply (+/- DC) but are limited in how much a voltage output can "swing to the rails" during operation. A rail to rail op-amp is designed to run off a single supply (here 9v) and the output can get very close to the positive rail while maintaining a high dynamic range.

Yeah, I don't see any reason for a TL074 not to work. I'm sure the TLE2074 was chosen in keeping with the idea of highest headroom / fidelity as possible. An alternative would be a different rail to rail like the TLC2264 which should be about half the price.

Ahh, case sensitive. I will fix that link.

http://www.madbeanpedals.com/projects/8Ball/8Ball_DRILL.zip

This should help with assembly. Actually on their website as one giant pic which I broke down into pages that can be printed.

Yup that'll be fine.

http://www.madbeanpedals.com/projects/ARCHIVE/FilterMod/PorkBarrel.zip

I think this is probably not terribly legal. Honestly, I don't know. But, oh lord, it looks like fun.

Progress has been made on the Tractor Beam (phaser) and is on schedule for release probably in 7-10 days. I got the audio board populated after waiting on a couple parts from Mouser. The Tractor Beam was originally called the Enterprise and is built on the same board. There are a few value tweaks from the Enterprise so the pot values here are not all accurate.

This will be a difficult build, but if you have done one of the VFE already it shouldn't be too bad. There is on electro that has to be soldered in parallel with a Zener (top right). There are three resistor networks (two 10k and one 22k). It also requires four matched 2n5952 FETs. I actually had a set I previously matched for a different project and was no longer using. The doc will have instructions on how to match FETs (I think I may have already covered this in the Phase 90 doc). The "B10k" is actually 1k now, and only having 2k on-hand I soldered in another 2k resistor in parallel with it.

Also, I have a FET matching board I may just put up on OSH Park. It was supposed to be part of a small batch of utility boards I was going to offer for sale but I never got around to it.

Anyway, to do: build the switching board and test it out. My prototypes for the re-designs of the VFE switching board will be here in a few days so I think I will wait and test one of those out with this build.

Yeah, I saved all that stuff.

http://www.madbeanpedals.com/misc/SKECO.zip

AFAIK it was never completely traced. Maybe 75% of the way. Couple unusual things about it: it uses two 2n7000 diodes for soft clipping in the second inverted op-amp of the PT2399 and it used inductors for two different LP filters at the PT2399 output. For the modulation, it uses an EA trem style LFO. From what I gathered, the LFO uses optical to modulate an LDR in parallel with a depth pot which is in series with the delay pot...but I'm not positive that's correct.