SSS Cut Control?

[bcmatt]

Would there be a major conflict to doing a treble cut control on an SSS with the post PI cathode follower? Could it go after the .1 PI caps before it hits the CF grids?
I built an MHartman SSS, that leans to very bright. I have the control panel knob where I had a Presence, but I have been quite happy with a rocket cut control instead of a presence in my Liverpool, and am thinking I'd love to go the same way in this amp too.
Are there some major problems that would occur in light of that CF being right there?

[martin manning]

You could do that, but I suggest you try a small change to the filter as suggested here: http://ampgarage.com/forum/viewtopic.ph ... 96#p371396 And, if you have an 0.002u cap to ground, increase it to 0.0033. You should get a better balance between treble and bass.

[bcmatt]

You could do that, but I suggest you try a small change to the filter as suggested here: http://ampgarage.com/forum/viewtopic.ph ... 96#p371396 And, if you have an 0.002u cap to ground, increase it to 0.0033. You should get a better balance between treble and bass.

Thanks Martin!
You are totally right! I did have the 0.0022u to ground as well as the version of the leg 7 that is not attached. I switched to your posted schematic of the new improved high filter (.003u, and all the rest), and it made a huge difference. I'm finally getting way more tones out of this amp because now I am not trying to primarily contain the treble. I am actually getting to use the bright switch, all the different high filter positions, and even my added presence control. I haven't played it a whole lot, yet, but from what I have, it is seriously getting addicting... I'm even loving the drive tone I'm getting with my mid boost, bright switch, and PAB all engaged when my volume is cranked. I've had to keep the master down today, but I can't wait to open this thing up!

Sorry to anyone waiting to hear how a cut control works in an SSS. All of a sudden, with the the treble filter working so much better that would be totally redundant.

[martin manning]

Fantastic! I was hoping someone would try out the revised filter. It looked good on paper, but the proof is in the sound.

[Krinkle]

This is great news. I'll be changing my filter, probably this weekend, so I'll be able to report back as well.

[bcmatt]

I haven't changed my bass filter side yet to make it increase bass as I go clockwise. I'm not super motivated since I don't currently hear that filter doing anything. I wonder if I somehow wrecked it when I added my PAB and mid boost switches. I think I will test with my Rhodes today to see if I hear it doing anything.

[martin manning]

Sounds like something wrong there. The bass side should be quite effective.

[Krinkle]

I haven't changed my bass filter side yet to make it increase bass as I go clockwise. I'm not super motivated since I don't currently hear that filter doing anything. I wonder if I somehow wrecked it when I added my PAB and mid boost switches. I think I will test with my Rhodes today to see if I hear it doing anything.

I can definitely hear my bass filter doing something, but mostly between 4 and 1 on my pot. Mine is on a 1M pot but it shouldn't matter. I'm going to change it to a switch just for kicks and set it up so the bass increases when I turn the switch clockwise. I don't have PAB in yet so I'll make sure I remember this when I add it.

[bcmatt]

Ok, my bass filter is working. Playing some lower notes with the Rhodes made it much more obvious. The deep switch is much more drastic as well. It's just that any 2 positions on the filter next to each other are very indistinguishable (even with Rhodes). Then from one extreme end of the filter to the other on the knob was quite subtle when on guitar but also, I think the key was that when playing at lower volumes. Bass becomes a lot more obvious when you open the amp up a bit more... duh!

[Krinkle]

Ok, my bass filter is working. Playing some lower notes with the Rhodes made it much more obvious. The deep switch is much more drastic as well. It's just that any 2 positions on the filter next to each other are very indistinguishable (even with Rhodes). Then from one extreme end of the filter to the other on the knob was quite subtle when on guitar but also, I think the key was that when playing at lower volumes. Bass becomes a lot more obvious when you open the amp up a bit more... duh!

That's good to hear. Okay, I guess I'll rebuild my filter section as per Martin and see if my Deep Switch does anything before I yank it out of there. Right now it does nothing.

[Bombacaototal]

In my opinion there are other mistakes on the filters

I think before them it should be like the attached

[Krinkle]

In my opinion there are other mistakes on the filters

I think before them it should be like the attached

Any particular reason? Just wondering. I'm used to seeing a single decoupling cap so a parallel network threw me off at first.

[Bombacaototal]

In my opinion there are other mistakes on the filters

I think before them it should be like the attached

Any particular reason? Just wondering. I'm used to seeing a single decoupling cap so a parallel network threw me off at first.

That is just how I see it when I look at the gut shots (ie #001)

[Krinkle]

I'm going to lift up that cap and try it.

[Krinkle]

Any chance you have the pic?