Tried a bright cap in my Suhr SL-67. Wow. Huge difference!

1956tvmodel

Active Member
Joined
Jan 30, 2009
Messages
140
Reaction score
151
Abut a year and a half ago I was looking around fork a Plexi style amp and cap across the Suhr SL-67. Really nice amp, all hardwired with some cool features that I haven't found on other Plexi style amps. For one It has a power scaling feature where you can run the amp at a full 50 watts and also run the amp at half power 25 watts and get a really cool compression. Its also has a master volume know on the back to bring the volume down to a more manageable level without sacrificing tone. Its a really beautiful amp.

With all that said there was still something missing to the sound. It just didn't have that Marshall type aggressive quality to it, Then I researched and realized that Suhr does not use a bright cap across the Volume pot and the more I researched I realized that is one of the things that gives a Plexi style amp that tone and bite. The amp sounded good but a bit lifeless and dull when compared to my 2203 and 2204 JCM 800s even. Pete Thorn who owns the 100 version of this amp, the SL-68 just put out a video on how he modded his to add a bright cap.

So I ordered a bright cap for like $2.00 and finally got around to checking it out. I read somewhere you can first test it out by hooking up alligator clips to the pot. Wow, to say it sounds a million times better would be a understatement. The chime and that bell like tone that was missing before is all there now. It also has that aggressive bite to the tone. The amp without the cap sounds dull in comparison. I think the cap I used is 100pf. I also ordered some 4700 pf caps to try which I think are even more aggressive. Its amazing the difference in tone for only $2.00. Now its time to solder it in for good!
 

Attachments

  • 8.jpeg
    8.jpeg
    123.5 KB · Views: 17
  • 6.jpeg
    6.jpeg
    123.9 KB · Views: 15
  • 5.jpeg
    5.jpeg
    129.1 KB · Views: 17
  • 4.jpeg
    4.jpeg
    88.2 KB · Views: 18
  • 3.jpeg
    3.jpeg
    110.2 KB · Views: 17
  • 1.jpeg
    1.jpeg
    82.1 KB · Views: 17

Emiel

Member
Joined
Jul 22, 2008
Messages
58
Reaction score
58
Definitely try a 4700pf cap in there.

The 100pf adds a bit of treble but with the 4700pf the amp is absolutely transformed. You won't like it as much with the channel volume below half way, but above it roars. That's why a lot of people opt to make the bright cap switchable with a push/pull pot.
 

1956tvmodel

Active Member
Joined
Jan 30, 2009
Messages
140
Reaction score
151
Definitely try a 4700pf cap in there.

The 100pf adds a bit of treble but with the 4700pf the amp is absolutely transformed. You won't like it as much with the channel volume below half way, but above it roars. That's why a lot of people opt to make the bright cap switchable with a push/pull pI ordered and it came today. I got a ceramic one a film type one. I also ordered a silver mica one but that hasn't arrived yet. Do the different types effect the tone as well or not so much?
Thanks.
 

1956tvmodel

Active Member
Joined
Jan 30, 2009
Messages
140
Reaction score
151
Definitely try a 4700pf cap in there.

The 100pf adds a bit of treble but with the 4700pf the amp is absolutely transformed. You won't like it as much with the channel volume below half way, but above it roars. That's why a lot of people opt to make the bright cap switchable with a push/pull pot.
Yeah I ordered a 4700 pf after watching Pete Thorns video. It came today. Surprised how much bigger these are than the 100 Pf. I ordered a ceramic and a film type. I also have a silver mica type which hasn't arrived yet. Do you know if the different types of caps make a difference on the tone as well?
Thanks
 

Attachments

  • 278566171_10216508081574181_237122380678182339_n.jpeg
    278566171_10216508081574181_237122380678182339_n.jpeg
    44.1 KB · Views: 1

1956tvmodel

Active Member
Joined
Jan 30, 2009
Messages
140
Reaction score
151
Definitely try a 4700pf cap in there.

The 100pf adds a bit of treble but with the 4700pf the amp is absolutely transformed. You won't like it as much with the channel volume below half way, but above it roars. That's why a lot of people opt to make the bright cap switchable with a push/pull pot.
Wow, you weren't kidding, Forget the 100 pf. I pu the 4700 Pf on the clips and im amazed. I thought the 100Pf sounded good but this is a whole other level. My 800s sound great but this amp with the bright cap cranked up with the output tube distortion and using the master volume sounds really great!
 

Attachments

  • 278751422_10216519437858081_1778703581756807613_n.jpeg
    278751422_10216519437858081_1778703581756807613_n.jpeg
    127.1 KB · Views: 5
  • 278735882_10216519438018085_2068642793983723334_n.jpeg
    278735882_10216519438018085_2068642793983723334_n.jpeg
    98.9 KB · Views: 5
Last edited:

Emiel

Member
Joined
Jul 22, 2008
Messages
58
Reaction score
58
Wow, you weren't kidding, Forget the 100 pf. I pu the 4700 Pf on the clips and im amazed. I thought the 100Pf sounded good but this is a whole other level. My 800s sound great but this amp with the bright cap cranked up with the output tube distortion and using the master volume sounds really great!

Pleased to hear that, enjoy! For me, the big bright cap is a must if you're running the channel volumes above 6 or so. The 100pf or no cap at all work better below half way up!
 


Top