Voici l'article ou plutot la réponse faite par Obiwannabe (http://obiwannabe.co.uk/) sur le forum de puredata.hurleur concernant les différences , quelques différences , commentées par Andy Farnell lui meme entre Csound et Pd...passionnant! (mais en anglais!) qui me conforte dans mon projet personnel de faire "travailler" ensemble plusieurs de ces softs afin de pouvoir utiliser le "meilleur" des uns et des autres! a vous de juger! le voici par simple copier-coller (vous le retrouverez par le lien suivant: http://puredata.hurleur.com/sujet-654-csound):
"I think it would be fairer to say thatl Pd is more 'efficient' than Csound. But to explain why it's necessary to explain why that's comparing screwdrivers to spanners a bit.
Csound was never designed as a real-time language. It came from an old Music V style design. As a very brief summary it's Barry Vercoes take on Max Mathews stuff that came out of a job based paradigm. It kinda got real-time by dint of computers getting faster while Miller took straight to a real-time approach  because Pd came out of early versions of IRCAMS Max patcher which was more midi oriented. Same under the hood but with a subtle difference. In Csound you have i-time as well as two computation times krate and arate. Pd has the same duality but these are the message domain and the signal domain. Pd doesn't have i-time (initial time), but you can make it yourself by precomputing tables and then raising a DSP=1 to start the program going. In Csound these can be part of a "note"  definition that lives in another file called the "score", while the patch is an "instrument" which is part of a collection called an "orchestra" file.. No score in Pd, Pd just sits there and listens for input or produces sounds by virtue of the message domain  program it's running.
Because Csound doesn't have the same time constraints it can take longer and compute in more detail.

Csound has a lot of special functions, it makes use of library things that would be "external" in Pd. What it doesn't have that Pd has is the ability to make "abstractions", so that complex things can be built in terms of lots of simple things and shared, reused and deconstructed easily.

Where Csound triumphs is accuracy and detail of sound quality. You can ask Csound to produce "impossible" scores that would never run in Pd/Max and set it rendering overnight. It's a different approach to composition than the interactive one on which Puredata wins. Think of it as a games engine vs 3D Max. The sense of "Max", whatever that may be,  is inverted.

How Csound achieves this is by design it can take as long as it wants to work something out. How Pd achieves its speed is that it uses practical approximations that will run in a guaranteed time. Pd is less accurate than Csound in most uses because it cuts some corners, but for the mostpart you don't hear these much.

This difference suggests two appropriate kinds of use. For design, interactive and real-time audio you would use Puredata. For final rendering of highly detailed soundscenes for a broadcast media like film you would render your ideas using Csound.

Hmm, so spanners and screwdrivers. But to answer the question, no, Pd is the more efficient, because it has to be, Or to use a car coordinate system Csound is possibly classier like a Merc, Bentley or Jaguar, while Pd is a Lamborghini or Aston Martin without being chavvy like a Lexus (Reaktor)."
Lisez la suite par le lien donné plus haut...carpe diem..Beryann