Jack Orman's Pickup Simulator / Anti-Buffer...

bifurcation

Well-known member
Anyone ever build/use one of these circuits?
pickup1.gif
I use a lot of different fuzzes in different configurations with a pedal switcher/looper (which has a built-in buffer) and I've been thinking about building a few of these to go in front of fuzzes. I wonder if stacking them will be a problem and/or if they undo some of the clarity that comes with buffers.

I also wonder if I could just build some buffers and tack this on the end of the circuit? Why doesn't everyone do that? (well, maybe because of the stacking issues?)

I also wonder if a certain PCB producer might make a little PCB module of this? (hint hint hint) ;)
 
Yes. After finding Jack Orman's "Guitar Pickup Simulator" post, I had to try one of each. They both do precisely as the article cites.

I can place one of these after my buffered wah pedal, just before my germanium Fuzz Face, and I get that good clean-up control back with my guitar's volume knob. It seems to work only one-pedal-deep in a pedal chain tho. When I moved the FF and FuzzBucker further into the chain, I lost the clean-up control with my guitar's volume knob. I just used stripboard builds.

I have to admit, I forgot it is a purely passive circuit and when I placed it into my chain, I automatically reached for a spare DC plug from the power brick - only to have a good chuckle at myself.

Going forward, I plan to incorporate these into the front-end of all my Ge dirt pedals. I don't think the pots are needed as fixed resistors will work well. But hey, more controls!

FuzzBuckers_Done.jpg FuzzBucker_Vero_1-Knob2.jpg FuzzBucker_1-Knob_Schem.png
 
Yes. After finding Jack Orman's "Guitar Pickup Simulator" post, I had to try one of each. They both do precisely as the article cites.

I can place one of these after my buffered wah pedal, just before my germanium Fuzz Face, and I get that good clean-up control back with my guitar's volume knob. It seems to work only one-pedal-deep in a pedal chain tho. When I moved the FF and FuzzBucker further into the chain, I lost the clean-up control with my guitar's volume knob. I just used stripboard builds.

I have to admit, I forgot it is a purely passive circuit and when I placed it into my chain, I automatically reached for a spare DC plug from the power brick - only to have a good chuckle at myself.

Going forward, I plan to incorporate these into the front-end of all my Ge dirt pedals. I don't think the pots are needed as fixed resistors will work well. But hey, more controls!

View attachment 5780View attachment 5781View attachment 5782
Hey man, it looks like you’re the closest to finding a Vero layout on the internet for an AMZ pickup simulator (congrats? 🏆)

I was wondering if you could spare a moment to draw one up for me. Happy to flick you some money for your time. If you have any closer photos of this Vero to help me understand that’d be grateful otherwise.

I know the schematic is right there but I hesitate to dip my toes into drawing up my first layout that has something like a transistor in it.

I need to add one at the start of my fuzz loop as I use wireless and the search to solve this problem has finally let me right here, to you 😅
 
Hey man, it looks like you’re the closest to finding a Vero layout on the internet for an AMZ pickup simulator (congrats? 🏆)

I was wondering if you could spare a moment to draw one up for me. Happy to flick you some money for your time. If you have any closer photos of this Vero to help me understand that’d be grateful otherwise.

I know the schematic is right there but I hesitate to dip my toes into drawing up my first layout that has something like a transistor in it.

I need to add one at the start of my fuzz loop as I use wireless and the search to solve this problem has finally let me right here, to you 😅
While I've never drawn up the Vero diagram, here is a shot of the solder side of the Vero build . . . . .

FuzzBucker_Vero_1-Knob3.jpg

So along with the top-side shot of the Vero build, you should be able to see how it is assembled and where the cuts are.
 
Yes. After finding Jack Orman's "Guitar Pickup Simulator" post, I had to try one of each. They both do precisely as the article cites.

I can place one of these after my buffered wah pedal, just before my germanium Fuzz Face, and I get that good clean-up control back with my guitar's volume knob. It seems to work only one-pedal-deep in a pedal chain tho. When I moved the FF and FuzzBucker further into the chain, I lost the clean-up control with my guitar's volume knob. I just used stripboard builds.

I have to admit, I forgot it is a purely passive circuit and when I placed it into my chain, I automatically reached for a spare DC plug from the power brick - only to have a good chuckle at myself.

Going forward, I plan to incorporate these into the front-end of all my Ge dirt pedals. I don't think the pots are needed as fixed resistors will work well. But hey, more controls!

View attachment 5780View attachment 5781View attachment 5782
@Cybercow Wow thank you for providing this schematic! I looked up the transformer and found a Xicon 42TM019-RC (data sheet attached) on Mouser is this the one you used? I haven’t found a frequency response curve yet, but the spec is +/- 3dB from 300Hz-3.4kHz, less worried about the high end, but it seems like the low end response might suffer. Can you speak to this?
 

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@Cybercow Wow thank you for providing this schematic! I looked up the transformer and found a Xicon 42TM019-RC (data sheet attached) on Mouser is this the one you used? I haven’t found a frequency response curve yet, but the spec is +/- 3dB from 300Hz-3.4kHz, less worried about the high end, but it seems like the low end response might suffer. Can you speak to this?
Yes, that very 42TM019-RC x-former is the one I used. And I did not notice the low end suffering.
 
@Cybercow Wow thank you for providing this schematic! I looked up the transformer and found a Xicon 42TM019-RC (data sheet attached) on Mouser is this the one you used? I haven’t found a frequency response curve yet, but the spec is +/- 3dB from 300Hz-3.4kHz, less worried about the high end, but it seems like the low end response might suffer. Can you speak to this?
I've used the 42TL019 as part of a pickup simulation sub-circuit in a couple of builds (Spaceman Sputnik II and Spaceman Gemini IV) and have had no issues with a lack of low end on either build.
 
Nit running it near it's max or even ideal current. Which is where it's tested .
If you're really worried, find a high quality Jensen, carnhill or the like with similar specs otherwise.
I'd start with DI transformers. But they're not cheap. 20x the xicons. So I'd start there and see what you find.
 
I bought that transformer, but I still didn't built the pickup simulator.
I have to say I afraid about the frequency range, too. And, because another kind of project, I'm finding other transformers, just a bit more expensive with wider frequency range, like: 60Hz - 25kHz or 20Hz - 20kHz.

Do you think it is a thing we can talk about?
 
FWIW, here are a couple of x-former charts I've collected over the years . . . .

42TLxxx_X-Former_Chart.png 42TMxxx_X-Former_Chart.png 42TUxxx_X-Former_Chart.png

The 42TLxxx series are the smallest at 0.591" deep, 0.591" wide and 0.5" tall.
The 42TMxxx series are a bit larger at 0.591" deep, 0.866" wide and 0.669" tall.
The 42TUxxx series are even larger at 0.72" deep, 0.98" wide and 0.74" tall - but are DISCONTINUED and available only as NOS where they can be found.
 
How much inductance is required? The article doesn't say. Tayda sells little inductors that look like resistors and/or capacitors, and I wonder if those would be suitable instead of a transformer coil. They're certainly way cheaper.
 
If I remember well, the inductance of the part that looks like resistors and capacitors are too small.
I know just this kind of transformer have the characteristic that can "emulate" pickup.

I include this, too. It can help to go close to the pickups specific.
Generically, the inductance is a bit lower in the single coil pickup, around 3H, and bigger in the humbucker pickup (4-5H).
Some higher output go over, until 12H. 21.7 I think is overkill, but I still didn't test anything like that, so I can't say what it really changes.

TM018-Inductance.png

What about the range of frequency of the transformer?
 
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I bought that transformer, but I still didn't built the pickup simulator.
I have to say I afraid about the frequency range, too. And, because another kind of project, I'm finding other transformers, just a bit more expensive with wider frequency range, like: 60Hz - 25kHz or 20Hz - 20kHz.

Do you think it is a thing we can talk about?
Triad Magnetics' TY-250P is good from 20Hz to 20kHz.

While TM's TY-250P is not as cheap as Xicon offerings, it has a much better frequency range and I think it is still very good value-for-money when compared to Cinemag etc

BASS!
 
I bought that transformer, but I still didn't built the pickup simulator.
I have to say I afraid about the frequency range, too. And, because another kind of project, I'm finding other transformers, just a bit more expensive with wider frequency range, like: 60Hz - 25kHz or 20Hz - 20kHz.

Do you think it is a thing we can talk about?
Triad Magnetics' TY-250P is good from 20Hz to 20kHz.

While TM's TY-250P is not as cheap as Xicon offerings, it has a much better frequency range and I think it is still very good value-for-money when compared to Cinemag etc

BASS!
It’s worth noting that the frequency range specs don’t matter -at all- in this application. We’re just using one side of a transformer as a cheap inductor in a pickup simulator. Effective frequency ranges of transformers only apply to the ‘transformation’ that they’re performing. For a project where you’re actually using a transformer as a transformer, by all means go for the Triad or Cinemag offerings, but it’d be a waste to use a nice transformer like that merely as an inductor
 
It’s worth noting that the frequency range specs don’t matter -at all- in this application. We’re just using one side of a transformer as a cheap inductor in a pickup simulator. Effective frequency ranges of transformers only apply to the ‘transformation’ that they’re performing. For a project where you’re actually using a transformer as a transformer, by all means go for the Triad or Cinemag offerings, but it’d be a waste to use a nice transformer like that merely as an inductor
I hear what you're saying, but I don't have a grasp on the science of this yet.

I've not much a grasp on anything — I'm still trying to make headway on input impedance, splitting the mids to hi-mid/low-mid on my Fig New-Tone, biasing my mu-amp project (reading EAE's MuBlaster description of the circuitry math made my brain hurt and kept me up all last night).
 
In concur. The frequency response on the transfor in this use is the frequency response of the enameled copper wire.
 
Hello.
Without open a new thread I want to ask here something about this Jack Orman project.
I built a version with the updated schematic, the one with Volume and Tone control, with no issue, and my built include even the early version. This:

fuzzbucker_1-knob_schem-png.5782

I testing it, without any other pedal. But switch and pot seem do nothing: no changing in the sound.
 
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