How to build a Fortin 33 / TC Electronics Integrated Preamp

vultures":zll33t2g said:
hopkinWFG":zll33t2g said:
Just a question for the op here.... appreciate your kind info and sharing here... as this particular has set my interest here.... as i looked thru and try to engage on electronic availability.... i was wonder how do you know C8 is ceramic 50V ratings ? And rest of the non polarized caps rating at 100V ?

I downloaded the schemetics and bills of materials it didnt list down the voltage ratings for non poplarized caps thou....

Ceramic capacitors are the most popular for the low capacitance rating (pF). It's difficult, although not impossible, to find film capacitors at those low ratings. I chose the MLCC 100pF because they're supposed to have better performance than a regular ceramic disk capacitor. The reason they are rated at 50v and 100v? They are the only ones on that website in that specific value, they just happen to be rated for 50v or 100v. They will still function fine.


If you'd really like to plug in all film, insane low tolerance, low voltage (40v) capacitors these might fit the bill. They're much more expensive and finding all the parts on Mouser is extremely tiring. I really wouldn't go any lower on voltage on these specific pedals.

100pF 5% 40v
https://www.mouser.com/ProductDetail/KE ... QHtA%3D%3D

47nF 5% 40v
https://www.mouser.com/ProductDetail/KE ... uOVbSMQ%3D

4.7nF 5% 40v
https://www.mouser.com/ProductDetail/KE ... 1gwq3q0%3D

22nF 5% 40v
https://www.mouser.com/ProductDetail/KE ... D6M4GHk%3D

220nF 5% 40v
https://www.mouser.com/ProductDetail/KE ... kjbA%3D%3D


Thanks vultures i do roger that... just a probe indepth... i do know the schemetic says 25V or higher and 35V or higher ratings for polarized caps.... in anyway will it change tonally if i were to might as well get them at 40V for all polarized caps ?
 
hopkinWFG":3lmxk1ss said:
vultures":3lmxk1ss said:
hopkinWFG":3lmxk1ss said:
Just a question for the op here.... appreciate your kind info and sharing here... as this particular has set my interest here.... as i looked thru and try to engage on electronic availability.... i was wonder how do you know C8 is ceramic 50V ratings ? And rest of the non polarized caps rating at 100V ?

I downloaded the schemetics and bills of materials it didnt list down the voltage ratings for non poplarized caps thou....

Ceramic capacitors are the most popular for the low capacitance rating (pF). It's difficult, although not impossible, to find film capacitors at those low ratings. I chose the MLCC 100pF because they're supposed to have better performance than a regular ceramic disk capacitor. The reason they are rated at 50v and 100v? They are the only ones on that website in that specific value, they just happen to be rated for 50v or 100v. They will still function fine.


If you'd really like to plug in all film, insane low tolerance, low voltage (40v) capacitors these might fit the bill. They're much more expensive and finding all the parts on Mouser is extremely tiring. I really wouldn't go any lower on voltage on these specific pedals.

100pF 5% 40v
https://www.mouser.com/ProductDetail/KE ... QHtA%3D%3D

47nF 5% 40v
https://www.mouser.com/ProductDetail/KE ... uOVbSMQ%3D

4.7nF 5% 40v
https://www.mouser.com/ProductDetail/KE ... 1gwq3q0%3D

22nF 5% 40v
https://www.mouser.com/ProductDetail/KE ... D6M4GHk%3D

220nF 5% 40v
https://www.mouser.com/ProductDetail/KE ... kjbA%3D%3D


Thanks vultures i do roger that... just a probe indepth... i do know the schemetic says 25V or higher and 35V or higher ratings for polarized caps.... in anyway will it change tonally if i were to might as well get them at 40V for all polarized caps ?

You can use larger values for voltages without any issues electronically, but usually the issue becomes if it will physically fit on the PCB. The higher the rating, the larger the capacitor, so you will reach a point where they just don't fit.
 
Interesting... has anyone ever compared this to a Boss FA-1?

I've built clones of those in the past; really cool clean boost,tones of output (+26dB if I'm not mistaken), and by engaging the Low Cut and simultaneously boosting the Bass a bit, you get a really tight and punchy boost.
 
Speeddemon":2o9c2a1h said:
Interesting... has anyone ever compared this to a Boss FA-1?

I've built clones of those in the past; really cool clean boost,tones of output (+26dB if I'm not mistaken), and by engaging the Low Cut and simultaneously boosting the Bass a bit, you get a really tight and punchy boost.

I built one of the byoc fa1 clones (has the same original op amp and fet as the original) and they’re similar in theory - both single op amp boost circuits followed by a baxandall eq, but that is about where the similarities end.

The FA1 distorts a lot easier (tc pre is clean), and the eq is different. Not as much cut or boost range on the FA1, and probably different center frequencies also.

I really like the FA1 on a clean channel to add a bit of grit, especially with single coils. But I didn’t find it anywhere near as useful as the tc preamp on heavy gain tones.
 
mnemonic":bpbn0rly said:
The FA1 distorts a lot easier (tc pre is clean), and the eq is different. Not as much cut or boost range on the FA1, and probably different center frequencies also.

I really like the FA1 on a clean channel to add a bit of grit, especially with single coils. But I didn’t find it anywhere near as useful as the tc preamp on heavy gain tones.
Wouldn't the additional grit of the FA-1 (I find it quite a pleasing sound myself) help with heavy tones as well? I mean, an SD-1 or a TS9 (the usual suspects for boosting mid/highgainers) with gain at 0 isn't totally clean either.

Can you elaborate on what you prefer on the TC?
 
Speeddemon":2kju8j2i said:
mnemonic":2kju8j2i said:
The FA1 distorts a lot easier (tc pre is clean), and the eq is different. Not as much cut or boost range on the FA1, and probably different center frequencies also.

I really like the FA1 on a clean channel to add a bit of grit, especially with single coils. But I didn’t find it anywhere near as useful as the tc preamp on heavy gain tones.
Wouldn't the additional grit of the FA-1 (I find it quite a pleasing sound myself) help with heavy tones as well? I mean, an SD-1 or a TS9 (the usual suspects for boosting mid/highgainers) with gain at 0 isn't totally clean either.

Can you elaborate on what you prefer on the TC?

Not saying it won’t work for high gain tones, I did try it out that way, but I thought it really shined for cleans, or low to mid gain boosting, where a TS or the TC worked better for me for high gain.

The clipping it introduces can be beneficial but it is different from the diode clipping you get from a TS pedal, as this is op amp clipping. It was also kinda noisy, but to be fair that’s probably down to the old out of production hitachi ha1457w op amp it uses. If you build one around a more modern and lower noise op amp like a 4558 or TL072, it will probably be a lot quieter (though the clipping will probably sound different).

This is just off memory as I haven’t used the fa1 clone in a high gain situation in like a year, but compared to the TC, it couldn’t cut as much bass or boost as much treble. I also liked how clean and clear the TC sounded, no clipping at all if you’ve got a high enough voltage power supply.

I remember thinking it was easier to get a ‘thick, sludgy’ tone with the FA1, where ‘tight, clear, punchy’ would be how I’d describe the TC with the usual settings.
 
Good info, thanks!

I did build my clones with the Hitachi opamps and I had to go above and beyond at the time to source these. Hell, I even provided AnalogMike some of my boards and op-amps, so he could build a few as well.
While I started out with a parts-perfect clone (carbonfilm resistors, greenie caps, and that specific tranny...246GR or something...I forgot) I did a few versions with metalfilm resistors as well. It did cut some noise, but to me, the circuit wasn't all that noisy to begin with (when supplied 9V from a properly filtered and isolated PSU).
As you said, it *did* have some almost magical thickening going on, especially in low-gain applications with Strats...but then again, so does a DOD 250, with level 10, Gain 0, and the silicium diodes replaced by 5mm green clearlense LEDs. The FA-1 is way more versatile with its EQ-ing...

I need to build me such a TC preamp too I guess. :rock:
 
Thanks Vultures for all the information. Got all my parts Friday and just finished it a few hours ago. Very cool pedal, running mine with 9vdc PS, charge pump it putting out 18vdc. I got about $25-30 into it. I highly recommend the breakout board, keeps things really clean. Also, the Alpha pots I got from Tayda electronics have a plastic cap on the back of the pot. Helps keep the components on board from shorting out on the back of the pot.

46736834054_1c77906215_c.jpg
 
bwgintegra":3amvo84h said:
Thanks Vultures for all the information. Got all my parts Friday and just finished it a few hours ago. Very cool pedal, running mine with 9vdc PS, charge pump it putting out 18vdc. I got about $25-30 into it. I highly recommend the breakout board, keeps things really clean. Also, the Alpha pots I got from Tayda electronics have a plastic cap on the back of the pot. Helps keep the components on board from shorting out on the back of the pot.

46736834054_1c77906215_c.jpg


Wow ! Nice !! But what did you do to secure da pcb ? And mind to share the size of the enclosure ?
 
hopkinWFG":2f1w5veu said:
bwgintegra":2f1w5veu said:
Thanks Vultures for all the information. Got all my parts Friday and just finished it a few hours ago. Very cool pedal, running mine with 9vdc PS, charge pump it putting out 18vdc. I got about $25-30 into it. I highly recommend the breakout board, keeps things really clean. Also, the Alpha pots I got from Tayda electronics have a plastic cap on the back of the pot. Helps keep the components on board from shorting out on the back of the pot.



Wow ! Nice !! But what did you do to secure da pcb ? And mind to share the size of the enclosure ?

The enclosure is a 125B style from Tayda. The PCB is secured by the solder joints of the three pots, didn't add any additional support.
 
This is awesome. Of course, I can barely make a sandwich...much less a pedal.

BTW - Fortin started shipping these again (and are now out again). A buddy from work just got one last week.
 
PeteLaramee":7ztflf10 said:
This is awesome. Of course, I can barely make a sandwich...much less a pedal.

BTW - Fortin started shipping these again (and are now out again). A buddy from work just got one last week.
I kept mine for a day before I sold it. It's okay, but not worth the $233 IMHO let olone the insane prices they where going for before the rerelease
 
Just finished building the integrated preamp and I’ve got a problem somewhere. I’m getting 9volts at the 9v wife on main PCB. I’ve got zero sound and the led doesn’t light even though I’m measuring power on the anode. I notice that when I begin to plug in the cable from my amp to the output jack on the pedal, the corresponding light on my power supply goes out. I’ve double and triple checked my connections. Can anyone enlighten me with a troubleshooting sequence. I’m lost.
 

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dlazzarini":1n756clo said:
Just finished building the integrated preamp and I’ve got a problem somewhere. I’m getting 9volts at the 9v wife on main PCB. I’ve got zero sound and the led doesn’t light even though I’m measuring power on the anode. I notice that when I begin to plug in the cable from my amp to the output jack on the pedal, the corresponding light on my power supply goes out. I’ve double and triple checked my connections. Can anyone enlighten me with a troubleshooting sequence. I’m lost.

If the light goes out on your power supply, you probably have a power short somewhere. Measure continuity across your power rails (+9v to ground), and see if you got continuity. If you do, you have a short that you need to find.
 
Thanks shask for the advice. I did find the problem. I had the dc jack wired backwards. All is good now. Pedal sounds awesome and suprisingly quiet.
 
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