Results 1 to 4 of 4

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

  1. #1
    Old Timer
    Join Date
    Oct 2011
    Posts
    1,951
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    9

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

    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.

    0 Not allowed! Not allowed!

  2. #2
    Old Timer soundguruman's Avatar
    Join Date
    Jul 2011
    Location
    California
    Posts
    2,522
    Thumbs Up/Down
    Received: 3/0
    Given: 0/0
    Rep Power
    10
    Quote Originally Posted by Alan0354 View Post
    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.

    0 Not allowed! Not allowed!

  3. #3
    Old Timer
    Join Date
    Oct 2011
    Posts
    1,951
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    9
    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.

    0 Not allowed! Not allowed!

  4. #4
    Senior Member
    Join Date
    May 2006
    Location
    Cornelius, Oregon
    Posts
    1,393
    Thumbs Up/Down
    Received: 68/0
    Given: 169/2
    Rep Power
    15
    Quote Originally Posted by Alan0354 View Post
    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

    0 Not allowed! Not allowed!

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Replies: 36
    Last Post: 03-26-2013, 06:18 AM
  2. Question about filter cap in ancient amp.
    By distorto in forum Maintenance, Troubleshooting & Repair
    Replies: 8
    Last Post: 06-23-2010, 03:51 AM
  3. Filter Cap Question
    By Jman in forum 5 E 3
    Replies: 3
    Last Post: 08-16-2009, 08:21 PM
  4. Ampeg V4 cap job using non-original value multi-caps...
    By acorkos in forum Maintenance, Troubleshooting & Repair
    Replies: 2
    Last Post: 05-11-2009, 03:47 PM
  5. Replies: 3
    Last Post: 08-28-2007, 04:47 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •