Tweaking discoveries. (All I got)

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Reeltarded
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Tweaking discoveries. (All I got)

Post by Reeltarded »

Early Circuit Cut Control

Parts: 250KL pot and a medium small cap, 2500-4000pF

The cap comes off the junction of whatever mixer you want to control to the right lug, the center lug is grounded.

Done. Bigger cap does the obvious. Helen Keller has nothing on you.

Clipping Diode Balance Control

I run clippers from pin 8 of the tube section that is the CF. a Jose without a volume control.

Parts: 5KL pot, 10k resistor, .22-.33u capacitor, and diode pair of choice.

Move the 100k to the tube, pin 8.

10k comes off CF output pin to .22 cap, diodes tail to tail ending at input lug of 5KL pot. Center lug is ground. A wire connects to the diode end of the cap and returns to the junction of the slope/treble to replace the lost connection from moving the 100k to pin 8.

Choose big dropping diodes if you don't use several on a switch for different flavors. Anything works, but with the pot controling clipping you can use a single pair of tiny ones and tilt it for more straight signal, or heavy squash. Check that your 5K reads totally shorted when closed or you don't get good range or extreme squash. 10k will totally dial them out of your path, normally by about 7-8k you can't hear a drop at all.

I am sure this has all been done by someone somewhere before, but I discovered these two ideas for myself trying to solve a simple problem. Discovery rocks!
Last edited by Reeltarded on Tue Nov 27, 2012 11:05 am, edited 3 times in total.
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cbass
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Re: Tweaking discoveries. (All I got)

Post by cbass »

Diagrams? My dyslexia is bad with words
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Reeltarded
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Re: Tweaking discoveries. (All I got)

Post by Reeltarded »

Wait until I am back at an adult computer with a keyboard and applications, not a screen to type on and apps.

Freaking game/phone/txt machines.
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statorvane
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Re: Tweaking discoveries. (All I got)

Post by statorvane »

So where is the output of the cathode follower to the PI? I am guessing the output is from one of the pot lugs? I am thinking you are using the 5KL pot as a voltage divider and no pre PIMV right?

Thank you,
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Reeltarded
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Re: Tweaking discoveries. (All I got)

Post by Reeltarded »

Edited above.

The 5k pot is a variable bleed to ground, a path for the diodes. A wire from the diode/capacitor junction returns to the slope/treble junction to complete the signal path. This does not add a volume control, per se, although the more you raise the resistance the less effect the diodes have, making the amp louder, and the more you shunt the diodes to ground the more attenuation you get with in your face clipping.

I dunno why clipping gets such a bad name. It is a great tool, especially for anyone needing more gain and attenuation at the same time. ;)

Plus it makes your amp sound HUGE at TV volume, period!
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martin manning
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Re: Tweaking discoveries. (All I got)

Post by martin manning »

Reeltard, I'm still not sure how you have the diodes wired when you say "tail to tail." They must be in parallel, no?
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Reeltarded
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Re: Tweaking discoveries. (All I got)

Post by Reeltarded »

Series, opposing pair. Anode to anode. The stripes are away from each other.
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Colossal
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Re: Tweaking discoveries. (All I got)

Post by Colossal »

If they are zeners, then series opposing pair (anode to anode). If standard diodes or LEDs, then parallel.
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Reeltarded
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Re: Tweaking discoveries. (All I got)

Post by Reeltarded »

LEDs don't do it for me, the 20v, 12v, and those 5.1v totally do it for me.
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martin manning
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Re: Tweaking discoveries. (All I got)

Post by martin manning »

Ok, that's the missing info... Zeners and voltage rating.
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Reeltarded
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Re: Tweaking discoveries. (All I got)

Post by Reeltarded »

Anything you have on hand works. These are my choices, but it all works. These are very modern profile. The LED is softer, germanium is softer. The silicon is forward and thumpy. Germanium is good. LED makes me solder again. :)

Mixing them up hasn't found any special magic for me. Maybe it's my choices, but identical opposing pairs let the amp control all the even-odd stuff where you expect it. I think that is a consideration.
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