Comparing sound of the amp with original filter cap value vs double each cap.

[Alan0354]

I just received my F T caps for my Pro Reverb, I put it in, but I want to do a comparison of the sound by comparing the sound with the original value to the sound when I double every single cap value.

I play the clean sound first with one speaker and replace the other one with a 10 ohm resistor to lower the volume. I have volume at 3.5, treble and bass at 5, bright switch off. Then I use my THD attenuator at -4dB ( reduce the output power a little over half) and cranked the volume to 6 to get the breakup. The sound did deteriorate a little with the attenuator but that's the only way I can keep the mic from breaking up.

1) With the new F T caps, two 80uF cap in series for the reservoir cap( original Fender is two 70uF). All the other caps are 22uF ( original Fender are 20uF). First clean, then second part is cranked with attenuator.

2) I switch in the caps from the original Fender, the reservoir cap is 40uF( two 80uF in series) plus 35uF ( two Fender caps in series)=75uF. All the other caps are 22uF +20uF=42uF.

Filter cap compare - YouTube

Tell me whether you can hear the difference.

[soundguruman]

I just received my F T caps for my Pro Reverb, I put it in, but I want to do a comparison of the sound by comparing the sound with the original value to the sound when I double every single cap value.

I play the clean sound first with one speaker and replace the other one with a 10 ohm resistor to lower the volume. I have volume at 3.5, treble and bass at 5, bright switch off. Then I use my THD attenuator at -4dB ( reduce the output power a little over half) and cranked the volume to 6 to get the breakup. The sound did deteriorate a little with the attenuator but that's the only way I can keep the mic from breaking up.

1) With the new F T caps, two 80uF cap in series for the reservoir cap( original Fender is two 70uF). All the other caps are 22uF ( original Fender are 20uF). First clean, then second part is cranked with attenuator.

2) I switch in the caps from the original Fender, the reservoir cap is 40uF( two 80uF in series) plus 35uF ( two Fender caps in series)=75uF. All the other caps are 22uF +20uF=42uF.

Filter cap compare - YouTube

Tell me whether you can hear the difference.

I can for sure tell the difference between "Illinois Capacitor" and F&T in Fender Amps.
The F&T sounds much better to me.
But not everybody has a musical ear, and not everybody will appreciate the improvements.

[Alan0354]

I don't know whether there is any difference between IC and F T. I don't have IC to compare. But I did hear slight difference between original value and double value. Maybe is just psychosomatic, the original value sounded a little smoother, maybe, the +B sag a little more. Maybe that's exactly the reason I like tube rectifier better as SS sounded too stiff to me.

[soundmasterg]

I don't know whether there is any difference between IC and F T. I don't have IC to compare. But I did hear slight difference between original value and double value. Maybe is just psychosomatic, the original value sounded a little smoother, maybe, the +B sag a little more. Maybe that's exactly the reason I like tube rectifier better as SS sounded too stiff to me.

Another thing you have to consider is what is the value currently of the original caps. They were probably +20% - 50% tolerance originally or something like that and over the years are likely to have drifted so they could have been something entirely different from what was printed on the outside. Their ESR is much higher than when new also most likely...a lot of things change in electrolytic caps over time and use.

Greg