I will build an amp using this schematic

Question

I will build an amp using this schematic.

http://sound.westhost.com/project27.htm

I came across a circuit. Which have Marshall and fender vintage amp simulator.

Details are here.

http://home3.netcarrier.com/~lxh2/marsh.html(With cabinet)

http://home3.netcarrier.com/~lxh2/marshprb.gif( without cabinet)

http://hem.passagen.se/amps

http://home3.netcarrier.com/~lxh2/

So i need merge them. With above schematic of Amp.

So i how can add it. Well its look like preamp. So should use it as an external preamp or just like stomp box. And secondly what must voltage in second circuit because it is not mentioned anywhere.

Any other advice will be appreciated.

Also suggest any Software designing for pcbs and circuit simulation for guitar amp. I currently use livewire and pcb wizard but few thing like power transistor and IC their library lacks.

Sorry for my bad English.

Answer 1

Those simulators should be used as separate pre-amps.  If you use them in-line in an effects loop, or as a stpmp box, then they *might* get over-driven and defeat the purpose.  It may be possible to use them as a stomp box IF they are the first ones in line right after the guitar pickup.

Unfortunately, the voltage to the op-amps must be bi-polar since that is the way the circuits are designed.  Both circuits (marshall and Fender) are the same in that regard.  A single 9V battery will not do.  A minimum of +/- 9V is needed.  It would be better to use +/- 12V or even +/- 15 volts.  If two 9V batteries are used and the results sound OK to you, then you can use two 9V batteries.  But, I suspect there will be a difference in the sound if you increase the supply voltage higer than +/- 9V, but that is only an educated guess.

As for circuit design software -- what you have sounds adequate.  For DIP IC packages you can probably draw your own with the available line and box tools in PCB wizard.

Good luck on your project.  I have a new type of direct-box that I am working on right now.

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