Re: [LAD] simulating analog audio devices part II

2007/6/18, porl sheean <porl42(a)gmail.com>om>: Xformers, valves, pots and speaker models courtesy of duncunamps.com: http://www.duncanamps.com/spicemodels.html The ogg I linked to in my previous email has been processed with LADSPA plugins for recreating the speaker filtering a bit more accurately, and to add a bit of reverb and delay. Sorry for not making it clear in my previous email. You should keep in mind though that the speaker models are made out of a simple network of resistors inductors and capacitors that only roughly mimics the interaction or "impedance dance" that exists between a power amp and a speaker. The mechanical aspects, the interaction of the paper cone colliding with air etc. can't be simulated in an ECAD program even though they contribute a lot to the final sound. For the theory behind the speaker models (reactive loads really) have a look at this link: http://www.aikenamps.com/spkrload.html My Carvin Legacy schematic is a bit borked right now since I am messing around and experimenting on it by replacing the power section with the one of an AX84's Firefly "open HW amp" (see http://www.ax84.com under legacy projects). In general there seem to be a lot of problems in simulating the power section of push-pull NFB enabled amps in LTSpice... the NFB starts oscillating producing really high frequencies even at modest volumes eventually inflating the sim duration to infinity... garanted that's also what happen in reality but only when the power section is severely distorting... Also keep in mind that by feeding a large number of high pitched notes simulation times increases... i.e an F# fretted at the 2nd fret/low E string is much quicker to simulate than an F# fretted on the 19th fret/B string, I hope this makes any sense. Cheers, -Giuseppe