Amp Build: Ceriatone Kraken 50

[FourT6and2]

I was thinking of installing a little trim pot on the board for the slope. But I'm not positive. A switch would be cool, too.

A trim pot on board would be neat.

I've done a slope pot on the front panel before, and drove myself crazy with the "fine tweekability", haha. I like the choices, but not that many, plus I prefer the exact indexing the switch provides.

Agreed. I tend to get analysis paralysis. Too many choices means I'm sitting there tweaking knobs to no end. I think either a 2 or 3 position switch would be good. Most tone stack switches I see switch out the cap and the resistor. But I think if I did it, I would keep the cap constant and just switch the resistor between 47K, 39K, and 33K. But I have a feeling I'd keep it in one position all the time.

 

[SpiderWars]

Agreed. I tend to get analysis paralysis. Too many choices means I'm sitting there tweaking knobs to no end. I think either a 2 or 3 position switch would be good. Most tone stack switches I see switch out the cap and the resistor. But I think if I did it, I would keep the cap constant and just switch the resistor between 47K, 39K, and 33K. But I have a feeling I'd keep it in one position all the time.

I've done it in a couple of amps and once I decided on my favorite setting it never changed after that. A trimmer inside doesn't hurt and ime it's easier to dial in if you add a 33k tail to a 25k pot. Then you know '0' is actually right at 33k.

Don't know if you have it or have messed with it much but the NFB resistor is a big contributor to the overall feel/tone. I made my Depth control a pull-pot so I can choose two different values. But ime the NFB resistor will have a more dramatic effect than the slope. I know they are two completely different things, just sayin' there's a lot of tonal tweaking value in NFB.

 

[idnotbe]

Though I am hearing through a cheap earphone... (i am in Thailand for my vacation)
It seems there is smoothness in ur last vids, especially with big slope value.
At least when comparing your Ceriatone clip.

It seems similar to Carol Ann tone to me.
Not exactly but similar...
Rounded mid~low to my ear.

 

[scottosan]

Agreed. I tend to get analysis paralysis. Too many choices means I'm sitting there tweaking knobs to no end. I think either a 2 or 3 position switch would be good. Most tone stack switches I see switch out the cap and the resistor. But I think if I did it, I would keep the cap constant and just switch the resistor between 47K, 39K, and 33K. But I have a feeling I'd keep it in one position all the time.

I've done it in a couple of amps and once I decided on my favorite setting it never changed after that. A trimmer inside doesn't hurt and ime it's easier to dial in if you add a 33k tail to a 25k pot. Then you know '0' is actually right at 33k.

Don't know if you have it or have messed with it much but the NFB resistor is a big contributor to the overall feel/tone. I made my Depth control a pull-pot so I can choose two different values. But ime the NFB resistor will have a more dramatic effect than the slope. I know they are two completely different things, just sayin' there's a lot of tonal tweaking value in NFB.

I agree on the NFB loop, although i don't like to use pots. Especially a 1M on the depth with an .0022 or .0047 is pretty much unusable all of the way up. I will take a pot and pick 3 spots I lie, measure them and put resistors on a 3 way switch.

 

[FourT6and2]

Agreed. I tend to get analysis paralysis. Too many choices means I'm sitting there tweaking knobs to no end. I think either a 2 or 3 position switch would be good. Most tone stack switches I see switch out the cap and the resistor. But I think if I did it, I would keep the cap constant and just switch the resistor between 47K, 39K, and 33K. But I have a feeling I'd keep it in one position all the time.

I've done it in a couple of amps and once I decided on my favorite setting it never changed after that. A trimmer inside doesn't hurt and ime it's easier to dial in if you add a 33k tail to a 25k pot. Then you know '0' is actually right at 33k.

Don't know if you have it or have messed with it much but the NFB resistor is a big contributor to the overall feel/tone. I made my Depth control a pull-pot so I can choose two different values. But ime the NFB resistor will have a more dramatic effect than the slope. I know they are two completely different things, just sayin' there's a lot of tonal tweaking value in NFB.

Yup, I used to have an amp with variable NFB. It was cool at first, but it got to be too much. I could never decide on a position. I'm pretty happy keeping the NFB where it is in this amp, which seems to be the typical hot-rodded Marshall value of 39K/8ohm tap.

 

[FourT6and2]

Though I am hearing through a cheap earphone... (i am in Thailand for my vacation)
It seems there is smoothness in ur last vids, especially with big slope value.
At least when comparing your Ceriatone clip.

It seems similar to Carol Ann tone to me.
Not exactly but similar...
Rounded mid~low to my ear.

Yup... the higher the value, the more focused and scooped the sound. Not really scooped... but it shifts the entire EQ curve down as a whole. So it's not like it's scooping out the mids alone. The stock Chupa/Yeti value is 47K, which is what Soldano uses I think. Stock Marshall is 33K in some amps. I think they used 39K at some point? I don't remember.

Seems like a three-way switch is a good option—Lo/Mid/Hi. I'll look into how to implement it.

 

[CrazyNutz]

you can put a 47k on board, then use a on-off-on toggle to parallel a 120k in left position to give you 33.77k, and 220k in the right position to give you 38.73k, the middle position would disconnect both the 120k and 220k and leave you with the onboard 47k

that would give you low/hi/mid, out of order but super easy to implement. or you could think of it as marshall/stock/deizel ?

 

[scottosan]

Agreed. I tend to get analysis paralysis. Too many choices means I'm sitting there tweaking knobs to no end. I think either a 2 or 3 position switch would be good. Most tone stack switches I see switch out the cap and the resistor. But I think if I did it, I would keep the cap constant and just switch the resistor between 47K, 39K, and 33K. But I have a feeling I'd keep it in one position all the time.

I've done it in a couple of amps and once I decided on my favorite setting it never changed after that. A trimmer inside doesn't hurt and ime it's easier to dial in if you add a 33k tail to a 25k pot. Then you know '0' is actually right at 33k.

Don't know if you have it or have messed with it much but the NFB resistor is a big contributor to the overall feel/tone. I made my Depth control a pull-pot so I can choose two different values. But ime the NFB resistor will have a more dramatic effect than the slope. I know they are two completely different things, just sayin' there's a lot of tonal tweaking value in NFB.

Yup, I used to have an amp with variable NFB. It was cool at first, but it got to be too much. I could never decide on a position. I'm pretty happy keeping the NFB where it is in this amp, which seems to be the typical hot-rodded Marshall value of 39K/8ohm tap.

I would still consider the depth/resonance a variable NFB

 

[FourT6and2]

you can put a 47k on board, then use a on-off-on toggle to parallel a 120k in left position to give you 33.77k, and 220k in the right position to give you 38.73k, the middle position would disconnect both the 120k and 220k and leave you with the onboard 47k

that would give you low/hi/mid, out of order but super easy to implement. or you could think of it as marshall/stock/deizel ?

That's basically what I did to test it out, sans switch, by paralleling a 120K/150K/220K across the 47K I already have on the board. Seems like the most simple way of doing it.

Hell, could do the same thing with the cap: 470pF/500pF/560pF. That way you actually have complete control over the combos and you have 9 total options from two switches (HEADACHE! lol).

 

[duesentrieb]

Just a guess, but I think Olaf might not like micas because of some people encountering ones that leak DC? I think I'm going to use those Philips KP caps. I seem to recall Larry and Aiken and a few other builders liking those. I have some in 100pF, 510pP, 470pF, and 560pF. I'll use the 100pF as the fizz cap and I haven't decided on treble cap values yet. The clips above are with 500pF treble peaker and 560pF tone stack treble cap.

I had about ten Micas leaking, Mike. In 3-4 amps.
Ever since I'm using the blue Muratas. 2kV.

 

[marcus262]

Yup. So I have a 1nF cap on the board in series with the V1 coupling cap to ground, before the gain control. Which I think does a similar thing. I might try putting the cap on the grid back and removing the one on the board as well. Turns out these amps (not just Ceriatone) usually have one or the other. But I mistakenly used both lol.

yes, if you use both you are cutting allot of stuff, I would go with ceriatone solution 150k/1nf combo on V1b grid because it is tested and works in ceriatone design.
In the grand scheme of things you are just removing high end from the first gain stage, second and third are receiveing a boost with all the cathode bypass caps. If you would remove one cathode cap and left just the resistor you would notice less gain and less fizz.

As far as gain, the clips I posted are with all the EQ/tone controls at 12:00. The gains are also around 12:00 - 1:00.

Second gain pot is already boosting highs with 470k/470pf peaker, but if you turn the first gain pot past 14 o'clock and up you should notice more high end frequencies... that may contribute to fizz. (this is without the diodes, I don't know how diodes shape the sound frequency wise)

But I think if I did it, I would keep the cap constant and just switch the resistor between 47K, 39K, and 33K. But I have a feeling I'd keep it in one position all the time.

you could try the switch that crazynutz posted and see if you like it.
As far as I can see on the schematic DC is blocked by a 220nf capacitor before the diodes and MV, because it is not a good idea to have high DC voltage on a little switch.

 

[CrazyNutz]

because it is not a good idea to have high DC voltage on a little switch.

Actually, they hold up quite well even with high dc voltage, and were talking very small current anyways.

Dave Friedman uses them to bypass voltage drop resistors (in the voltage + - switch on the phil x amp), that has the whole preamp pulling HV through it.

 

[CrazyNutz]

Just a guess, but I think Olaf might not like micas because of some people encountering ones that leak DC? I think I'm going to use those Philips KP caps. I seem to recall Larry and Aiken and a few other builders liking those. I have some in 100pF, 510pP, 470pF, and 560pF. I'll use the 100pF as the fizz cap and I haven't decided on treble cap values yet. The clips above are with 500pF treble peaker and 560pF tone stack treble cap.

I had about ten Micas leaking, Mike. In 3-4 amps.
Ever since I'm using the blue Muratas. 2kV.

Thats disturbing, I have however suspected this, Especially with the common solid black ones. I've pulled those out of the PI fizzy cap location, and replaced them with the brown CDE before and made a big differece in some amps. I'm going to test for leakage on these now.

 

[FourT6and2]

Just a guess, but I think Olaf might not like micas because of some people encountering ones that leak DC? I think I'm going to use those Philips KP caps. I seem to recall Larry and Aiken and a few other builders liking those. I have some in 100pF, 510pP, 470pF, and 560pF. I'll use the 100pF as the fizz cap and I haven't decided on treble cap values yet. The clips above are with 500pF treble peaker and 560pF tone stack treble cap.

I had about ten Micas leaking, Mike. In 3-4 amps.
Ever since I'm using the blue Muratas. 2kV.

Thanks, Olaf. Yeah I've heard of people with similar problems. I'll look into the Muratas. Any reason not to try those blue Philips KP series? I don't see too many people using foil caps in pF values in guitar amps. Usually mica or ceramic. I guess because those are easier to find?

Data sheet: http://www.farnell.com/datasheets/28681.pdf

 

[FourT6and2]

Just a guess, but I think Olaf might not like micas because of some people encountering ones that leak DC? I think I'm going to use those Philips KP caps. I seem to recall Larry and Aiken and a few other builders liking those. I have some in 100pF, 510pP, 470pF, and 560pF. I'll use the 100pF as the fizz cap and I haven't decided on treble cap values yet. The clips above are with 500pF treble peaker and 560pF tone stack treble cap.

I had about ten Micas leaking, Mike. In 3-4 amps.
Ever since I'm using the blue Muratas. 2kV.

Thats disturbing, I have however suspected this, Especially with the common solid black ones. I've pulled those out of the PI fizzy cap location, and replaced them with the brown CDE before and made a big differece in some amps. I'm going to test for leakage on these now.

All of the problems I've heard about are with the black ones.

 

[marcus262]

Actually, they hold up quite well even with high dc voltage, and were talking very small current anyways.

Dave Friedman uses them to bypass voltage drop resistors (in the voltage + - switch on the phil x amp), that has the whole preamp pulling HV through it.

yep, you are probably right.
I personally just don't feel safe touching metal switches with HV DC, especially with those regular small switches ceriatone uses...
if something fails... one finger on metal part the other on guitar which acts as ground and there you go... you would have the opportunity to really feel the amp

 

[FourT6and2]

yes, if you use both you are cutting allot of stuff, I would go with ceriatone solution 150k/1nf combo on V1b grid because it is tested and works in ceriatone design.

To be fair, Ceriatone has done it both ways. My stock Chupacabra 50 has just the cap 1nF cap on the board and no cap on the grid/tube. But mine is an early version. More recent amps have just the 1nF cap on the tube socket (no cap on the board). Seems like either way works.

 

[FourT6and2]

Actually, they hold up quite well even with high dc voltage, and were talking very small current anyways.

Dave Friedman uses them to bypass voltage drop resistors (in the voltage + - switch on the phil x amp), that has the whole preamp pulling HV through it.

yep, you are probably right.
I personally just don't feel safe touching metal switches with HV DC, especially with those regular small switches ceriatone uses...
if something fails... one finger on metal part the other on guitar which acts as ground and there you go... you would have the opportunity to really feel the amp

Those switches Ceriatone uses can be found in Friedman, Bogner, Soldano, Bogner, etc. They're the same ones you can get at Tube Depot, AES/TAM, TAD, Mouser, Digi-Key, etc. The metal bat/switch can not come in contact with any part of the circuit. I've taken them apart. Inside, the switch tip is isolated. There's a thick piece of plastic between it and the terminals. The switch body would have to literally melt and come apart in order for current to get to the switch tip. It's certainly possible. But what would it take for that to happen?

Data Sheet: https://s3.amazonaws.com/tubedepot-com- ... 1400100687

 

[marcus262]

To be fair, Ceriatone has done it both ways. My stock Chupacabra 50 has just the cap 1nF cap on the board and no cap on the grid/tube. But mine is an early version. More recent amps have just the 1nF cap on the tube socket (no cap on the board). Seems like either way works.

Oh, great if they have done it both ways, than for sure it would work

Funny thing is when I looked at your photos of Chupa few months ago I couldn't see 1nf cap on the grid. I thought that it was maybe obscured by something, well that explains it

I've taken them apart. Inside, the switch tip is isolated. There's a thick piece of plastic between it and the terminals. The switch body would have to literally melt and come apart in order for current to get to the switch tip. It's certainly possible. But what would it take for that to happen?

Thank you for that information, i didn't know they were isolated with thick plastic.
I was just going with "better safe than sorry" kind of approach.

 

[scottosan]

Just a guess, but I think Olaf might not like micas because of some people encountering ones that leak DC? I think I'm going to use those Philips KP caps. I seem to recall Larry and Aiken and a few other builders liking those. I have some in 100pF, 510pP, 470pF, and 560pF. I'll use the 100pF as the fizz cap and I haven't decided on treble cap values yet. The clips above are with 500pF treble peaker and 560pF tone stack treble cap.

I had about ten Micas leaking, Mike. In 3-4 amps.
Ever since I'm using the blue Muratas. 2kV.

Thanks, Olaf. Yeah I've heard of people with similar problems. I'll look into the Muratas. Any reason not to try those blue Philips KP series? I don't see too many people using foil caps in pF values in guitar amps. Usually mica or ceramic. I guess because those are easier to find?

Data sheet: http://www.farnell.com/datasheets/28681.pdf

For my BE100 clone, I used WIMA FKP (Polypropylene) for my 100pf, 220pf, 500pf, and 680pf