Sujet Modification sur le 20/20 mesa boogie power amp.

Salut,
j'ai vu qu'une modif sur cet ampli de puissance afin de rendre le son moin medium, avec plus de basses était réalisable.
Je voulais savoir si ça marche vraiment, et si l'ampli ne risque rien.
Merci

Guillaume.


MODIF :
Doing this modification will give more low end "oomph", add richness, and open the treble a bit more. I find it gives you a more "modern" mix of vintage EL84 chime and new metal sound. This amp is a little too washed in the mid frequencies as stock. Here's how you do it (if you aren't tech / electronically inclined, find somebody who is!! Amps store high voltages even when unplugged and if you poke or prod the wrong thing, you can be electrocuted)


1. Take off the cover
2. Locate the 12ax7 input tube closest to the input jacks, this will be the farthest tube to the left if standing behing the amp with the tubes pointing to you.
3. Look at the circut board the input tube is mounted on. Slightly below the tube on each side of it, you'll see a series of capacitors / resistors. These are miniture "sausage" looking things about a 1/4" long, running up and down. Some are tan/brown with stripes, some aren't.
4. You'll see one in each grouping per side that is different. They are a bit smaller than the rest, NO STRIPES, and are a yellowish/tan color, and have tapered ends. THESE ARE THE ONES YOU WANT TO REMOVE.
5. One is very easy since its by itself to the left of the input tube. The other one on the opposite side is in between the other "sausage" looking devices (resistors).
6. I removed them by heating the back side of the circut board where its soldered in. Using very long, thin needle nose pliers (or a long thin screw driver). I disconnect on side of the capacitor from the circut board. Gently pry out the connection while applying the heat to the connection.
7. Repeat on the other side. Be careful not to damage the resistors next to it.


Enjoy the sound. If you don't like it, re-solder the connection. Thats why its good to only remove one end, its easier to re-connect.