Fender FR-12 preamp mod : The Hissterectomy

I'm willing to bet money the preamp is an in-house design by Fender. The power amp is built and designed much, much better overall.
You could be right. I worked on a blues jr a while back. And the board was just about as cheap as you could possibly build one.

I kinda suspect this is an old Kustom bass/keyboard design pulled out of mothballs. ... the truth is probably somewhere in the middle.


If they have a fix... then we all have a warranty claim. Well not me 😂 mine is an alien autopsy now.
 
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I'm glad the cheap Ba$tards are having to buy BurrBrowns and adapters, plus shipping and reworking the boards. Rework is a pain in the a$$. They should have built it right to start with.

Using your ideas will cost them a lot. Wait till they start smoking BurrBrowns and compression drivers from bad design .
 
I need confirmation; someone in TGF claims to have gotten a brand new FR-12 from Fender which is basically factory-modded 😡

https://thegearforum.com/threads/fender-fr-10-fr-12-noise-reduction-mod.3559/post-157520

View attachment 131821

The EQ opamp ICs were replaced with OPA1664s - a fine choice for this application, with a very low noise floor - but, surprisingly, one i haven't seen suggested elsewhere so far.
Wait, what? They’re sure it wasn‘t a return that someone modded on their own?

-Aaron
 
They claim the amp came straight from the factory, and i have no reason to doubt it so far.

Those SOIC opamp ICs, for example, look very cleanly soldered to the DIP adapters.
Those adapters don't look like the ones available from the usual places either.

That TDA2050 looks like it got smashed pretty hard tho.
 
They claim the amp came straight from the factory, and i have no reason to doubt it so far.

Those SOIC opamp ICs, for example, look very cleanly soldered to their DIP adapters.
Fair point. I watched a bunch of SOIC SMD soldering videos before I did mine and thought “this is cake, I can do that no sweat.” Then 1 1/2 hours of swearing and bleary-eyed hallucinations later I had the equivalent of Homer Simpson’s BBQ Grill steaming in a pile of flux on my bench. o_O

-Aaron
 
Fair point. I watched a bunch of SOIC SMD soldering videos before I did mine and thought “this is cake, I can do that no sweat.” Then 1 1/2 hours of swearing and bleary-eyed hallucinations later I had the equivalent of Homer Simpson’s BBQ Grill steaming in a pile of flux on my bench. o_O

-Aaron
I’m just good at soldering, but I have some colleagues/friends that are excellent. :)
I’m glad Fender is addressing it and I bet there are engineers at Fender that are as well.
 
I'm willing to bet money the preamp is an in-house design by Fender. That Hanser/Kustom power amp section is built and designed much, much better overall.
It makes sense as Fender would have been very concerned about the “voicing” of the circuit. Or at least they should have been. But who knows? Still, I give them major credit for resisting SMD and building something that is easily hot rodded. Kudos to Fender for doing this. As @WKSmith and yourself have discovered, the circuit is straightforward and easily modified. Amps and speakers have been modded to artist’s specs forever and this cab is no exception with respect to its ability to be modified. Try doing the same with any of the other designs out there !
 
Well hell. Fender became alarmed about the noise issue. I’m sure they were well aware when they released the new cabs. Probably had meetings where the pin heads decided to try and save a few bucks and pass it off anyhow noise and all. Then they saw the posts and what you guys were doing. Blew both of you off then basically stole Lysander’s idea. I’ll give you guys credit for making them do something instead of blowing smoke. Great work @WKSmith and @Lysander! I appreciate you guys!
 
Fender’s fix will not impact their bottom line and they will sell a ton of these speakers. At least until Marshall wakes up. :)
 
I have very conflicted feelings on this...

As someone who has zero comfort with modding electronics, I am far more interested in this than purchasing a mod I have to in any way install myself.

At the same time, seems pretty blatantly ripped off which is definitely bad form.

Would be nice to hear some sort of formal comment on this change. Maybe there's still a chance that [EDIT: I didn't follow this closely enough to get the users right, appropriate credit given in next post] will get a shout out?

...probably not.
 
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I have very conflicted feelings on this...

As someone who has zero comfort with modding electronics, I am far more interested in this than purchasing a mod I have to in any way install myself.

At the same time, seems pretty blatantly ripped off which is definitely bad form.

Would be nice to hear some sort of formal comment on this change. Maybe there's still a chance that @WKSmith will get a shout out?

...probably not.
@Lysander gets the shout out for the opamp substitutions. I just dropped in a couple of opa2134s in the first and last two stages. Then rebuilt the eq from the ground up. My preamp isn't as picky about opamps.
 
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