Best Clean Fender AIAB

ac30irons said:
Thanks dude, I’m just not looking at going that deep with it. I’m basically looking to do my own version of the Crazy Tubes HiPower.
Click to expand...
If that’s the case you want a power booster and hiwatt style circuit. The Aion Fx ST-2 is supposedly Cornish take on the powerbooster. It’s a lot cleaner than other PB circuits I’ve tried.

IMG_5923.jpeg
 
Passinwind said:
Cool, just riffing on my usual workflow. For clean stuiff I typically would start by modeling the actual original tube circuit in LTspice, then look at impedance scaling to an opamp circuit as appropriate. The only guitar AIAB tangent I've really worked so far outside of many Fender bassed ones was Dumble oriented, and all three I've built so far are radically different from each other. That's not necessarily such a bad thing though!

For my wants and needs Hiwatts have gotten my attention more as a bass thing, and in my case using a DR103 output transformer clone with 4 x EL-34 worked out really well for me.
Click to expand...
Thanks for your input
 
The Aion take on the Lab Series, the Lab Series Preamp Clean Channel is a Black panel inspired preamp. Bonus Robert Moog compressor. It's a tad spendy for parts but I think it's right up your alley and totally nails what Moog (Gibson back then) intended to be a Twin killer. You can use this beast to drive a power amp as well should you decided to use it as the front end of a rig.
 
ac30irons said:
Thanks dude - I think we have established that you are far more talented than I !!!
Click to expand...
Nah, not my intent at all. But in any case, I'm definitely interested in expanding my tone stack horizons and Hiwatt looks well worth some investigation. I have my model for a stock DR103 up and working now, and will do a proper build thread once I decide on whether to go with tubes or opamps.
 
Last edited:
Passinwind said:
Nah, not my intent at all. But in any case, I'm definitely interested in expanding my tone stack horizons and Hiwatt looks well worth some investigation. I have my model for a stock DR103 up and working now, and will do a proper build thread once I decide on whether to go with tubes or opamps.
Click to expand...
If you go with opamps that can be adapted to pedal format easily.
 
FYI, I've been working on an all-in-one fender clean amp that fits in a 125B. I haven't shared it yet but it is very close to finished and is being tested by a couple other folks. It has The following independent modules on one PCB:
  • jfet fender style preamp and it is EQ matched to a real fender preamp.
  • AMT series II cabsim.
  • Clean amplifying stage to come up to line level to drive a TPA3118 piggy-backed onto the PCB.
  • Balanced line driver for send to a PA.
It also has some options for power supply. If using a TPA3118, then it's powered by 20 to 24VDC, 2 or 3A that is stepped down to 15V for the jfet preamp. If not using a TPA3118, then can use direct 15V power or can install a voltage doubler to power with 9V.

The PCB is finished and have built a few examples and have a few PCBs. Eventually, the plan is to share the PCB at PCBway. But, I don't yet have a build document.

Here's an early rev of the PCB populated but not with a TPA3118 power amp. It's not a beginner project... Uses small 1/6W resistors and alpha 9mm pots. Each module on the PCB is separate so you decide what to wire up. If anyone is interested in building, PM me. One other builder and I are building now and creating build documentation. P1020623.JPG
P1020485.JPG

Here's one with a TPA3118 and send/return jacks.
Screenshot 2025-03-28 164043.png
 
Paul.Ruby said:
FYI, I've been working on an all-in-one fender clean amp that fits in a 125B. I haven't shared it yet but it is very close to finished and is being tested by a couple other folks. It has The following independent modules on one PCB:
  • jfet fender style preamp and it is EQ matched to a real fender preamp.
  • AMT series II cabsim.
  • Clean amplifying stage to come up to line level to drive a TPA3118 piggy-backed onto the PCB.
  • Balanced line driver for send to a PA.
It also has some options for power supply. If using a TPA3118, then it's powered by 20 to 24VDC, 2 or 3A that is stepped down to 15V for the jfet preamp. If not using a TPA3118, then can use direct 15V power or can install a voltage doubler to power with 9V.

The PCB is finished and have built a few examples and have a few PCBs. Eventually, the plan is to share the PCB at PCBway. But, I don't yet have a build document.

Here's an early rev of the PCB populated but not with a TPA3118 power amp. It's not a beginner project... Uses small 1/6W resistors and alpha 9mm pots. Each module on the PCB is separate so you decide what to wire up. If anyone is interested in building, PM me. One other builder and I are building now and creating build documentation.View attachment 124947
View attachment 124948

Here's one with a TPA3118 and send/return jacks.
View attachment 124952
Click to expand...
Looks awesome dude and sounds even more ! Are releasing the pcb and schematic - I would be super interested in recreating the pre-amp section.
 
ac30irons said:
Looks awesome dude and sounds even more ! Are releasing the pcb and schematic - I would be super interested in recreating the pre-amp section.
Click to expand...

This is the fender pre-amp final build but it has options. Components marked "LINK" are jumper wires. "XXX" means nothing installed.

R7 and R8 are option jumpers to the power supply circuitry. This pre-amp likes to have 12V but will work fine from 9V to 18V.

There is a gain pot but also have the option for hard-wired setting of gain with R12 and R30. This schematic shows my chosen values for R12/R30 and no gain pot installed. These values are chosen to avoid clipping in the two following gain stages. Clipping there does not sound good. Feel free to use a gain pot instead with this warning... The voltage divider of R5 and R20 is also used to ensure the following amplifier stage is not over driven when using low voltage for the whole pedal.

I tried many different jfets to get the right gain and bias without needing to fiddle. J113 from Mouser were very consistent and just right.

@temol ... This started from the AMT F1 and ended up here after 4 iterations and ended up much more closely matching the Particle Accelerator pre-amp from sushi box. I even included C1 100pf to match the 12ax7 grid capacitance of the tube pre-amp to get an exact EQ match to the real fender pre-amp.
1790180581927.png

This is (roughly) the preamp section of the PCB. The modules are not each perfect rectangles. For example, the voltage doubler (if used) is U4 (or U5).
1790181458617.png
 
You must log in or register to reply here.
Back
Top