Fender FR-12 preamp mod : The Hissterectomy

[WKSmith]

Its getting close now

 

[Deadpool_25]

Its getting close now
View attachment 131647

Wtb.

 

[Lysander]

Its getting close now

LDR? Dafuq?

 

[WKSmith]

LDR? Dafuq?

instead of the stock jFet and shunt regulator gimmick that grounds the audio for a turn on delay, I am using the Vactrol to slowly and gracefully fade in the audio after the amps turn on.

 

[Lysander]

instead of the stock jet gimmick that grounds the audio for a turn on delay, I am using the Vactrol to slowly and gracefully fade in the audio after the amps turn on.

Nice!

 

[WKSmith]

it also has a tiny aux pcb for the horn and led connections. The whole thing installs into the stock holes using the stock plugs or sockets.
no soldering. no drilling. and really nice components.

 

[davi_ssilva]

Cool!!! Are you also keeping that idea of a clipping warning LED that lights up behind a transparent volume knob?

 

[Rockuronium]

I received my FR-12 yesterday. Guitar Center wasn't lying about the open box thing--the box it arrived in was completely shredded. Thankfully, the FR12 was unharmed.

The hiss is definitely real. Not loud enough to matter in a band setting, but enough to be irritating at home levels. It's unfortunate Fender released it with this obvious flaw. I'm looking forward to the WKSmith upgrade.

Hiss aside, the FR12 sounds fantastic. I wouldn't say it's 100% the same as playing through a real amp/cab, but it's probably 90% there, which is far closer than anything else I've tried. Lots of inspiring tones to be had, and I found myself playing with different amps I never thought really had utility before in the FM3 (e.g., the Two-Rock model).

 

[WKSmith]

Cool!!! Are you also keeping that idea of a clipping warning LED that lights up behind a transparent volume knob?

absolutely! The led lights up the clear volume knob, but the clip detector circuit is actually fed post EQ.

 

[davi_ssilva]

absolutely! The led lights up the clear volume knob, but the clip detector circuit is actually fed post EQ.

Awesome! This feature is so important that's hard to grasp why Fender left it out!

 

[jellodog]

This feature is so important that's hard to grasp why Fender left it out!

Is it though?

 

[IAmThePepperoniKing]

I'm happy with my LFR112, but I would 100% buy an FR10 or 12 if I could get @WKSmith 's board. This is awesome!!

 

[WKSmith]

Here are the boards mocked up beside the stock pre.

 

[rjones5766]

Add me to the list - was going to pick up a pair of FR10s when they launched but the hiss reports have held me back - would happily mod a couple of units with WKSmith's boards if/when he launches!! Looks like great progress - time to start posting timeline and pricing - how about a waitlist? ;-)

 

[morrissey007]

Add me to the list - was going to pick up a pair of FR10s when they launched but the hiss reports have held me back - would happily mod a couple of units with WKSmith's boards if/when he launches!! Looks like great progress - time to start posting timeline and pricing - how about a waitlist? ;-)

An alternative is to replace two of the TL084 with OPA4227PA chips, 30 minute job; hiss gone.

 

[WKSmith]

- time to start posting timeline and pricing - how about a waitlist? ;-)

to quote a few folks here ...soon

 

[davi_ssilva]

An alternative is to replace two of the TL084 with OPA4227PA chips, 30 minute job; hiss gone.

It's a good alternative, yes. But the WKSmith Mod not only kills the hiss, but also gives us a clipping monitor and a higher quality and more streamlined circuit, which is potentially more reliable, more durable and more easily repaired in the case something goes wrong in the future. And it does not involve soldery, which is a big plus in my book.

 

[WKSmith]

from the unwritten FR manual.. page 1

a) Do not connect the FR XLR out to a mixer with phantom power! There is zero phantom power protection in the FR series, with the exception of the Ground lift switch. The ground lift switch does not affect the XLR input, only the XLR output. The ground lift switch lifts the ground connection when pressed IN and without the ground plane phantom power is not a complete circuit. Phantom power will absolutely toast the FR.

b) The input impedance for the balanced line in of the stock FR is 5K.

 

[Joe Bfstplk]

Phantom power will absolutely toast the FR.

They built it with no protection from ID10T sound dude's accidental application of phantom power and call it a piece of pro gear????

 

[WKSmith]

They built it with no protection from ID10T sound dude's accidental application of phantom power and call it a piece of pro gear????

they most certainly did.
It needs to be in bold print somewhere ..that the XLR out is designed only for driving a second FR.