Fatpants as a buffer? Also can it handle super hot pickups?

[thebigkevdogg]

Hey everybody, please forgive my ignorance as I'm new to a lot of this. I'm thinking about building a fatpants as an always on kind of pedal at the start of my board - basically a buffer with some coloration, and i might twist the volume knob a bit when I'm about to take a solo. A few questions:

• Does it have a pretty good (high) input impedance and low output impedance?
• Can it handle really hot pickups? I mostly play pedal steel guitar and my output is hot - for example I had to really play with the internal trims on my 2 knob keeley compressor to get it not to clip
• Finally, how easy would it be to wire in a switch that would bypass the boost circuitry and turn it into just a simple buffer? What section of the circuit would I bypass?

Thanks so much!
Kevin

[9Lives]

I etched a fatpants from the old layout and it worked great with my duncan blackouts. A bit of a different type of "hot" but my pickups clip almost every circuit with/o major tweaking. The charge pump helps and if I'm not mistakin it even has an out put topower another pedal at 18v if you wanted. I recommend it. It's definitely a good beginer project with great results. My guess.. Yes it would work with your pickups. It's not really the same as a buffer though, but I get what your saying. Just put your compressor infront of it. Then fatpants.

[thebigkevdogg]

Thanks for the response, especially the pickup info. I guess the buffer questions come from this in the PDF:

The 2012 version adds a JFET input buffer, a new Body switch for high-gain/full spectrum boost and a re-tooled output section.

I'm wondering if it's possible to somehow enable a mode where it just uses the input and output buffers but skips the boost circuitry?

[9Lives]

I'm not familiar with the new layout. I'll definitely check it out, that sound like somthing I'd like.i am familiar with switching between sections. You wouldn't need both buffers. You could simply switch between the input buffer and the whole circuit with a DPDT. I'm going off the top of my head w/o the layout b/c I'm on my phone but I'm guessing you would tie I separate wire off the source of the fet. Look at the amz (muzique.com) lab note book and look at the tubescreamer buffered bypass wiring. It's all of 2 extra parts and actually makes the whole process way easier. I do this ALL the time, or any time my circuit utilizes an input buffer . Your idea is good. Do me a favor and check out the article. I'll look at the pdf and help you convert it from transistor to jfet (if you need me to) the article uses the transistor input buffer. Your jfet will work better. It maybe tom or later when I can look at it.

[jkokura]

Thanks for the response, especially the pickup info. I guess the buffer questions come from this in the PDF:

The 2012 version adds a JFET input buffer, a new Body switch for high-gain/full spectrum boost and a re-tooled output section.

I'm wondering if it's possible to somehow enable a mode where it just uses the input and output buffers but skips the boost circuitry?

Without looking into if it's possible, you wouldn't really want to do that I don't think. If you do want to do something like that, just buy a Boss pedal of some sort. The buffer in that does about the same thing. If you have ANY buffer on your board it'll do the same thing.

In this case, the input jFet buffer is simply a simple gain stage. It's not really doing anything except presenting the "fatpants" circuit with a clean, clear and strong signal.

I'll go back to the orignal questions:

1. Yes, high input impedance, low output impedance.

2. Yes it can handle hot pickups.

3. Instead of wiring a switch that would bypass the circuitry, I'd wire in a switch that replaced the volume knob with a second volume knob. That way you could have 'boosted' and buffered. Rather than setup with a bypass switch, just have one switch that toggled between the two knobs.

I'm not sure what you're expecting out of a buffer, but methinks you don't quite understand the purpose of a buffer or how one uses one.

Jacob

[thebigkevdogg]

9Lives, thanks for the info - I will check the amz site out.

jkokura - it is definitely possible that I am misunderstanding things. Here are my observations - my amp has 2 patches, one before and one after the EQ section of the preamp. I have found that my steel sounds better/more alive running straight into the amp and then with all of my pedals in the pre eq section of the amp than it does going guitar => pedals => amp. The first pedal in my chain is a boss TU-2 that is always on in the bypass mode, so my signal is hitting a buffer already. I just figured that the difference that I hear may be due to a cheap and/or bad buffer in the TU-2. Am I mistaken? FYI the amp is a Peavey Nashville 112 (it's a pedal steel amp).

Thanks!

[thebigkevdogg]

I guess I'm thinking about something similar to the Durham Buff Master Pre - i thought the fatpants would be a good base as many people seem to be using it as an "always on" effect.

http://www.durhamelectronics.com/products.html

[Effectsiation]

There are quite a few buffers out nowadays.  A while ago they used to be terribly taboo what with the True-Bypass craze.  As someone who has a FatPants, I mostly use it for Coloring.  It makes an OK boost I guess, but I pretty much leave it on for a song, if I feel the coloring would benefit the song.

Anyway, I think what Jacob was saying is that the "buffer" in the FatPants isn't really providing everything you ideally want or could have from other buffers.

Here are some resources for other buffer-specific projects:

GGG IC-based fabbed PCB:
http://www.generalguitargadgets.com/projects/15/74-simple-ic-buffer

Cornish Transistor-based VERO:
http://tagboardeffects.blogspot.com/2012/02/cornish-buffer.html

Klon Buffer VERO:
http://tagboardeffects.blogspot.com/2011/04/klon-buffer.html