Is there a reset button for a Vox Valvetronix 100watt amp AD100VT, if so where is it located?

Cpontact Vox (Korg USA) customer service at this link-

bulbs have tolerance, that means it can work with + or - 6.3v just use the 7.6v which a diffrence of 1.is ok for it to work.

Consider reading the Manual for this amp, it explains how to reset to factory with the VFS5 footpedal. Or with the power off ..hold down CH1 & CH4 then turn power on.. when the Bank & Channel leds start blinking.. then release the Channel buttons. Next press the Tap switch ... the bank & channel leds will change from blinking to lit. with in a few seconds it will enter preset mode.

that is because it is two different output channels. eventually you will blow the speaker or your amp. It wasn't designed to handle the impedance of an external speaker through the stereo
headphone jack. Are you sure that your speaker is hooked up or plugged in?

Hi it could be that the switch has failed if it is something you are not confident with ask an independent electronics repair shop for some help. Sorry I cannot help more but I cannot see how the switch can be seized in the on (Depressed) position.

At this point it sounds like you've done all you can do by yourself. Time to take it to the shop.

i live in mexico and musics stores here sucks I'm an engineer and y started experimenting i think its an IC the TAS5615 im about to order it but does anyone know for sure what it could be??

Yes you could blow the speaker. There is either a problem in the power supply or possibly the power amp chip has shorted to one of the power rails. Some of the vox stuff uses th LM3886 chip as the power amp. While these are supposedly protected, they can go bad. Download A schematic that MIGHT be close to your unit... it is for the VT30 but probably is similar:

http://elektrotanya.com/vox_ad15-30vt_sch.pdf/download.html

Scroll down to "Get Manual" and click on it to download the schematic. Do this test: Adjust the power level control. IF it doesn't vary the level significantly, then check the voltage across the speaker... IF it isn't less than 1 volt DC (bias) replace the LM3886 chip. Use thermal grease and any insulators they are using. Chip about $8 from Digikey.com. Note these come with two different pre-bent leads... make sure to get right ones. IF the output bias is with 1 volt DC of ground, check for bad filter caps and rectifiers.