CATHOD CAPS FOR TRAINWRECK EXPRESS

[heisty]

Hi does anyone have ideas on different value cathod caps and the tone interactions with lowering resistor values around cathod stages?

[gearhead]

Go to aikenamps.com and check out his technical section (advanced I believe). Has a writeup on it.

[heisty]

Thanks mate will check that out when i get some time Cheers

[heisty]

what i was really after was if i dropped the cathode resistor down from say 1/2 watt to 1/4 watt and would this wattage handle voltage for the first cathode and what sort of affect would this have on tone and the same with lowering the input 68k resistor wattage down ????

[paddy]

Hi Heisty

Changing the wattage of these resistors won't make any noticeable
difference in tone.It is their resistance value that matters here.
Try it if you like,it is safe to do so.The 1/4 resistors will easily handle
the current flowing in these areas.

Cheers
Paddy

[heisty]

Hi thanks mate,will give it a go,just thought that the lower wattage might make the amp more touch responsive in some sort of way , new to this still learning here ill try and post results
Cheers

[gearhead]

Going with lower wattage resistors -could- potentially increase noise, as per Randall Aiken:

"Larger wattage resistors are quieter than smaller ones, due to the geometry of the part, so you should always use the highest power rating you can find, particularly in carbon composition resistors."

WRT making more touch sensitive, building one to what the trailblazers have discovered and documented throughout this site should get you there.

[heisty]

Thanks gearhead , also with the express there is a 10k resistor on cathode of 2nd preamptube, will using a larger value drop gain and why is there no cathode cap in parrallel with this resistor? can someone help out here?

[heisty]

Thanks gearhead , also with the express there is a 10k resistor on cathode of 2nd preamptube, will using a larger value drop gain and why is there no cathode cap in parrallel with this resistor? can someone help out here?

[Noel Grassy]

Thanks gearhead , also with the express there is a 10k resistor on cathode of 2nd preamptube, will using a larger value drop gain and why is there no cathode cap in parrallel with this resistor? can someone help out here?

The cap paralled with a resistor allows more bottom to pass. In this amp I believe Ken's thought may have been about the degree of "mud" or "flabb" that the next gain stage would be multiplying . Hence the sole R. Check Aiken in the previous suggestions for sure [it's not difficult following that man's descriptions thankfully]. Compare how Fender & Marshall dealt with it in their early designs too. Marshall goes wimpy "out-the-gate" with .68 uf as the cathode cap where Leo sports the chunky 22uf's in successive stages. This is definately where you become the tunist in terms of a complex & rich signal or a farty or anemic signal prior to going into the PI. My summary is longwinded & retarded compared to Mr Aiken's nuggets of amp wisdom. Bank on it, NG

[Johnhenry]

Noel, you said it all in 1 sentence,
Quote : " This is definately where you become the tunist in terms of a complex & rich signal or a farty or anemic signal prior to going into the PI."
If that make's you retarded, then I'm still rubbin 2 stick's together to make fire,
Johnhenry

[heisty]

Thanks guys thats what ive thought , theres so much to be had in the cathodes and different values, if you dont bypass with a cap doesnt that give the signal more punch and headroom so ive heard??
is it better to have large caps in the early stages and drop values down as u move down the line ?
Cheers