It's still there, but not as loud.
Fender FR-10/FR-12 noise reduction mod
- Thread starter Lysander
- Start date
What would be the result if they weren't installed correctly? No sound at all?
Lysander
Shredder
- Messages
- 2,236
Basically.
Any sonic differences after changing EQ opamps in the FR-10/12 should be negligible - if not downright inaudible. Specially for frequency response, which is determined by other components on the board.
Hmm, I feel like it's gotten bassy and muffled. I'll have to swap the original parts back in to make sure I'm not going insane.
aflynt
Roadie
- Messages
- 167
Might just want to reflow the solder joints and make sure none of the connection wires have frayed. I thought I heard a difference between the TL084 and OP4227 in the first 14 pin position, but it wasn’t “bassy and muffled” either way. Are all the controls working properly? IE: cut is cutting highs, treble control adding/ removing highs, etc…
-Aaron
fretworn
Rock Star
- Messages
- 4,158
See the U-shaped divots?
OK, so away from the pots is correct.
aflynt
Roadie
- Messages
- 167
The orientation in your picture is correct. The 14 pin ICs are placed the opposite way from the 8 pin ICs on this PCB. For this package type, the big U shaped indentation as mentioned above marks the side where pin 1 is.
-Aaron
Yzman
Newbie
- Messages
- 2
@Lysander thank you so much for all your hard work! Installed 3 OPA4227PA chips last night and the difference in hiss is night and day. This is the best powered speaker I’ve tried to date now that the hiss is virtually gone.
Couple small tips for anyone attempting this who is a novice like myself.
To get the chassis out, start with the 8 black screws then, the 2 silver screws on top. Next lightly push down on the chassis from the top with increasing pressure until it breaks free, seems to be stuck on.
The 3 three wires with white connectors on the main board will need to be separated by cutting the small zip tie. Two will disconnect from the amp board and one will disconnect from the main board. These wires only disconnect at one end, the other end is fixed to the board.
The rest is straight forward.
Couple small tips for anyone attempting this who is a novice like myself.
To get the chassis out, start with the 8 black screws then, the 2 silver screws on top. Next lightly push down on the chassis from the top with increasing pressure until it breaks free, seems to be stuck on.
The 3 three wires with white connectors on the main board will need to be separated by cutting the small zip tie. Two will disconnect from the amp board and one will disconnect from the main board. These wires only disconnect at one end, the other end is fixed to the board.
The rest is straight forward.
Lysander
Shredder
- Messages
- 2,236
Thanks you for the confirmation!morrissey007
Newbie
- Messages
- 12
Three OPA4227PAs arrived today, I put turned pin sockets in, I also the front end RC4885 (XLR balanced Input IC) with an OPA 1234 and the hiss has reduced dramatically. However, I now have a problem with it going to max volume if I push sideways on the volume control or press on the input socket, so I fear I may have damaged something when replacing the chips, its almost like there's now a loose connection somewhere near the input. further investigation; when I put the top two silver screws in I can reproduce the popping, seem like if I flex the chassis slightly I can reproduce it every time now, so I suspect a dry joint (but I have 50 years of soldering under my belt!) or a slight crack in a track. Back to the bench to remake every joint and inspect under a high powered magnifier. I wonder if a spare board is easy to obtain!
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lolainnb
Roadie
- Messages
- 114
Well that does it for me. No way I’ll attempt it
Lysander
Shredder
- Messages
- 2,236
That sounds like a cracked solder joint on the pots; they squeeze in very tightly when getting the preamp board out - or in. Re-fluxing the joints should be enough, IMHO.
The input socket is physically disconnected from the board though, so
Stratzrus
Roadie
- Messages
- 802
I think the mod is great and by all accounts it provides major improvements. But while my father, an electrical engineer, taught me how to solder when I was 6, my skills are rusty at best and I'm really concerned that I could mess it up.
morrissey007
Newbie
- Messages
- 12
It’s relatively easy to do, however, I strongly advise a change in the dismantling process; remove the small board that holds the XLR sockets BEFORE removing the preamp board. Doing this extra (very easy) step avoids the need to bend the pots as the preamp board can now just slide out. I think what happened to mine is that when bending the volume pot to remove the board it has separated the solder pad from the pcb track. I’m Investigating more this morning.
morrissey007
Newbie
- Messages
- 12
Yu[p, tried reflowing the joints but didnt make any difference, I think a Pad has separated from a track. As I said above, remove the XLR board also, its only 4 screws and this extra step could save a lot of troubles. I'll report back later today!That sounds like a cracked solder joint on the pots; they squeeze in very tightly when getting the preamp board out - or in. Re-fluxing the joints should be enough, IMHO.
The input socket is physically disconnected from the board though, so
