Fender Frontman 65R volume mod

[Five Aces]

Hi J M

Interesting but where can you get these pots Fender (uk) don't do them and Fender (us) don't do them and even when they did they were charging approx $7- $8 each plus p&p for something that cost then less than a $1 to buy.
You seem to be the man with the knowledge can you help, it's a Frontman 65r (Type PR 557)
I would have just fitted normal 16mm pots but there is no room, any ideas?
Many thanks
Stephen

Just as they said, there is no need to change the 50K pot at all! Just replace R15 with a 10K resistor and leave the pot as is. It is enough to do the job! I was quite satisfied with the results, It smoothed out the lower range of the volume such that 0-3 was more controlled...

[oc disorder]

Another alternative... master volume inserted in efx loop (send & return before pwr amp).

I jiffy box, 2 jack plugs (with cut down covers), 1 pot, scrap wire and a bit of mucking about !


Hey presto master vol... as long as your not using the loop.

[curryman86]

Most of the pots on this amp are shot, that is why I want to replace them, as stated in my post these are unavailable

[oc disorder]

Dunno how hard you are looking ???
Fender Amp Potentiometers | Parts Is Parts - Guitar Parts, Amplifier Parts, Korg Keyboard Parts

treb c50k 0069524000 DISCONTINUED, NO LONGER AVAILABLE
bass B50K 006268000
norm vol A50k 0037323000
Drive C100K 0037324000
Drive Vol A50k 0037323000
treb C100k 0037324000
mid B50k 006268000
Bass B25k 0049402000
Reverb B50k 006268000

http://darrenriley.com/store/fender-...0r-0069524049/

Fender Control 50K 30C FM65R/210R 0069524049 Fender part# 0069524049 (same as 0069524000)

http://darrenriley.com/store/fender-...0r-0062680000/

Fender Control Snapin 50K B FM65R/210R 0062680049

etc

[curryman86]

Hi oc, I looked very hard, just like you have done and I thank you for it.
Unfortunately the pots you have found I also found but they are the wrong type
Yes I could fit them then change all the knobs but why should I have to, I believe fender should hold these parts in stock.
I believe I have now sourced these pots, I'm waiting for them to arrive, once I have checked them they will be available at half fenders price
Thanks again oc for your efforts
Kind regards

Curryman86

Picture of the correct type pot with knurled shaft ........
.

[oc disorder]

Thanks for filling me in. Would have thought when the part has the amp model number next to it (not all did) it would be the correct part.

So they are still C.T.S. pots ! The 296 series.

http://www.ctscorp.com/wp-content/up...015/11/296.pdf

I'll have to look harder next time !

[g1]

The Darren Riley links were the correct type (knurled shaft).

[curryman86]

Sorry g1 they are not all correct for my amp plus at $9.95 they can stick'em where the sun don't shine, mine are coming in at half that price

[Jazz P Bass]

Sorry g1 they are not all correct for my amp ,mine are coming in at half that price

So where are you getting them from?

Please share the source.

[curryman86]

Jazz P Bass,
"I believe I have now sourced these pots, I'm waiting for them to arrive, once I have checked them they will be available at half fenders price."

[Steve A.]

I skipped most of these posts and didn't look up the schematic but I used an entirely different approach to my very similar Princeton 112+ and 65 amps: I added a master volume pot to the feedback loop of the last IC stage before the FX loop. I wired the MV as a variable resistor which at full volume was maybe 25% higher than the stock value to allow for more volume from the clean channel. (I mounted the added MV on the back panel.) It worked for me...

Steve Ahola

P.S. Okay here are some specifics. I would replace R59 with a 50k linear pot in series with a 12k to 22k fixed resistor, and might tweak the taper and range with a larger resistor (120k?) across the pot terminals. With the added pot on the back panel it is easy to experiment with different values.





Here is FM65R schematic...


fm-65r-schematic.pdf

[Jazz P Bass]

Nice & elegant, Steve.

Thanks for posting that.

[Steve A.]

On the PCB it works better to replace R59 with a large value resistor and wrap the flying leads to the added pot around the legs of the resistor.

The Princeton 112+ had a horrendous POP when turning it off so one reason adding the MV was to make it more stage-friendly. The Princeton 65 wasn't quite as loud and I would hope that Fender finally solved that problem with the Frontman 65.

Steve Ahola

[Fredgold52]

I just came up with a very simple and cheap way to make the volume control easier to deal with and to reduce the HISS. I put a 250k ohm pot in line with the hot wire in the 1/4 inch plug. I put that end in the amp and turned everything on. In the "0" ohm position the amp is normal. Same jumpy volume control and same hiss. As I added resistance with the pot, the volume came down and started to act like a 'normal' amp. I also noticed I was able to use the treble and bass knobs without adding to the much reduced hiss I was hearing.

Feeling very satisfied with myself, I removed the cable/pot from the amp and guitar to see what resistance I had that gave me results I liked. It turns out that 45k ohms is the magic number. So a simple way to deal with this would be to solder a 45k ohm resister in series with the 'tip' lead. How easy can this get???

I'm of course not going to do that. I'm about to assemble a 1/4 inch jack and plug along with a 250 kohm pot into a small black plastic box. The new volume attenuator will live with the amp permanently. I'm doing it this way because I love having knobs to turn. Short commercial here, Blue Star Musick sells a Schattner Black Box for $40.00 that will do the same thing.

That's it from here. Have a great time with your FM 65 R

[fastfolkert]

Just as they said, there is no need to change the 50K pot at all! Just replace R15 with a 10K resistor and leave the pot as is. It is enough to do the job! I was quite satisfied with the results, It smoothed out the lower range of the volume such that 0-3 was more controlled...

BUMP: R15 is in series with C9. Aren't you introducing tone/sound changes when R15 is replaced by 10 kOhms?
(I have a Princeton 112+ and a Champ 25 (hybrid amp), both with this volume-issue)