Fender FR-12 preamp mod : The Hissterectomy

WKSmith said:
I'm not here to sell preamps 😉👍

🤣😂😅

This is example of them making themselves look stupid. Those jumpers.. there are 30 or so of them
..so they can use a single sided board and save just a few cents. But it has no ground plane on the top side (which faces to the front of the FR and is pointed straight at the guitar pickups) and the chassis is not a complete shielded enclosure, more like an L shape. That's just dumb!

Whoever designed this pre has a bright future building curling irons and coffee pots.

How a legacy brand like big-F put this out and put their name on it (after a year and 3 revisions and a secret IC swap "hiss fix") is beyond belief.

Here's some pro advice for F-corp "engineers"...

1) Buy a Doug Self book on small signal audio, especially the gain staging and filter design chapters, and maybe even power amp design, and read it... Twice

2) Buy a Walt Jung book before buying ICs, and learn how to read a dang data sheet.

3) Fire the accountant that built this pre.
Click to expand...
Maybe Fender knew all along that is cheaper to create bad V1 designs and wait for you to do the fixing for them. Someone here works for Fender

I wonder who the impostor is?


IMG_0289.jpeg
 
LolainNB said:
Maybe Fender knew all along that is cheaper to create bad V1 designs and wait for you to do the fixing for them. Someone here works for Fender

I wonder who the impostor is?


View attachment 135017
Click to expand...

Lol. That’s pretty good. I have no doubt they did some lurking here and on TGP. And I’m assuming plenty of Fender employees play guitar and some of them use FAS modelers. So it’s possible.
 
I have been picking on them pretty hard. All in good fun. But they could save a some money on the preamp and whole lot of back-peddling if they had licensed the V2 design.

I can tease them a little bit, only because the complete V2 re-design is a drastic improvement over the stock pre... which already sounded pretty great.

But they would have to handle themselves much better on the customer relations side before I would ever put my name on their pre.
 
Another nice fix from the V2 circuit!

The stock FR preamp is 180° out of phase from the input signal.

The V2 is in phase.

This matters a lot if you use the FR in stereo or dual mono with another cab like the EV PXM, or in a WDW rig with an amp, or even two FRs with a V2 in just one of them .

One FRFR out of phase with the other will cancel each other out.. especially in the low end.
 
Last edited:
WKSmith said:
Another nice fix from the V2 circuit!

The stock FR preamp is 180° out of phase from the input signal.

The V2 is in phase.

This matters a lot if you use the FR in stereo or dual mono with another cab like the EV PXM, or in a WDW rig with an amp, or even two FRs with a V2 in just one of them .

One FRFR out of phase with the other will cancel each other out.. especially in the low end.
Click to expand...
Wow! Does this mean that I'll have to wait until I get your board before I can use my existing FR-12 V1 with my EV-PXM as a stereo pair?
 
ltarlton said:
Wow! Does this mean that I'll have to wait until I get your board before I can use my existing FR-12 V1 with my EV-PXM as a stereo pair?
Click to expand...
You can use two different outputs on the Fractal ..and flip the phase of one output in the setup audio config menu.

You may also be able to use a block to split the signal and reverse phase of one out. Like the enhancer block (in classic mode), or perhaps the mixer block.

The balanced input in the FR sums the +/- signals so you can't just flip the xlr cable pins on one end.
 
Last edited:
skolacki said:
They seriously did that?! That’s F’d up. Really lame unless there’s a phase switch.
Click to expand...
It's their jacked up eq design.
The first two and last two amp stages are right. The 12 eq amp stages in the middle are just stupid.

It is easy to test. I played a sine wave track into the FR. Ran the xlr out (copy of xlr in) of the FR, and a mic into two tracks in the DAW.

The mic waveform is 180° out from both the source sine wave track and the FR xlr out.

If you do the eq bypass mod with a piece of wire a (few posts up ^ )..The phase should be correct.
.... but I haven't seen anyone bypass the eq yet, Which is exactly what I expected. 🤣
 
Last edited:
@WKSmith - Hi WKSmith of the Archangel Clan :)

Have you decided whether you prefer either the FR-10 or FR-12? I'm ready to place my order but I'm on the fence about which to go for. I like small, portable and lighter of the FR-10, but I play blues, pop, and classic rock and don't want to lose too much heft in the low end. I'm curious if you (or anyone else whose tried both) have any comments about the sonic differences and which you prefer.

Thanks for creating these preamps. It is super cool and exciting!

Best,
Scott
 
For anyone interested, I had zero experience with a solder, let alone electronics but tried to gather what I could and powered through to get this mod done, and I could not be happier.
A massive thank you to Lysander, WKSmith and all everyone else who spent the time, energy and dedication to find a fix for this issue, and helping so many such as myself.

I myself, having zero knowledge or an inkling of where to begin would have loved to have had a video or detailed images walking me through. For this reason I've done my best to attempt a detailed guide of the process, and drafted it up with photos in a google docs.

Unfortunately I am unable to attach the link here, but have done so in another comment on the the gear forum. If anyone has any other suggestions other than a google docs link for attaching it I'm open to hearing it!
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom