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Step 4Inserting the circuit
Exactly where should the clipping circuit be added? Well... first, where NOT to place it...
--Don't insert at the input circuit (before the preamp.) Guitar signals are quite weak, and even if the circuit functions partially with a really hot pickup, it likely won't work at all with other guitars.
--Don't insert in the driver portion of the power amp (output transformer primary.)
--Don't insert in the output transformer secondary / speaker loop.
The last two examples will greatly attenuate (lessen) the volume of the amp, probably "fry" the diodes, and possibly ruin the power tubes or the output transformer.
So, where should it go?
--Within, or just after the preamp circuit. The red line illustrates the signal path between the preamp and the output stages. This amp has a single preamp stage, so this is the only acceptable place (in this case.)
The points B and C are all possible places to connect the clipping circuit. I chose C, since this amp is never too loud, and turning down the volume will change the character slightly. Connection point B are probably better if you wish to retain the full clipping effect when the volume control is turned down. Point A is unsuitable, due to the DC plate voltage.
Amps with a dual-tube preamp are ideal--any signal attenuation lost in the clipping can be recovered by increasing the gain of the second preamp stage. (Of course, that pre-supposes that you have the expertise to do so...)
There will be some attenuation with diode clipping--some signal will be lost. This isn't really tragic, however. Most players would prefer to get "that sound" at lower volumes.
--Don't insert at the input circuit (before the preamp.) Guitar signals are quite weak, and even if the circuit functions partially with a really hot pickup, it likely won't work at all with other guitars.
--Don't insert in the driver portion of the power amp (output transformer primary.)
--Don't insert in the output transformer secondary / speaker loop.
The last two examples will greatly attenuate (lessen) the volume of the amp, probably "fry" the diodes, and possibly ruin the power tubes or the output transformer.
So, where should it go?
--Within, or just after the preamp circuit. The red line illustrates the signal path between the preamp and the output stages. This amp has a single preamp stage, so this is the only acceptable place (in this case.)
The points B and C are all possible places to connect the clipping circuit. I chose C, since this amp is never too loud, and turning down the volume will change the character slightly. Connection point B are probably better if you wish to retain the full clipping effect when the volume control is turned down. Point A is unsuitable, due to the DC plate voltage.
Amps with a dual-tube preamp are ideal--any signal attenuation lost in the clipping can be recovered by increasing the gain of the second preamp stage. (Of course, that pre-supposes that you have the expertise to do so...)
There will be some attenuation with diode clipping--some signal will be lost. This isn't really tragic, however. Most players would prefer to get "that sound" at lower volumes.
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The coupling cap will remove any DC bias.