Re: [LAU] another cpu question

On Sat, 13 Sep 2014, Ede Wolf wrote: My guess is that this will be used live then? So you must have an audio interface in mind and a channel count. I am guessing that this will end up rackmount with a MB that has PCI(e) slots? Will it have a gui screen? or be run via MIDI/OSC/custom control surface? (I would recomend something sort of standard as it may be nice to have a MIDI control surface on a desk particularly for EQ use... though a touch notepad Interface might work too) Because you have (I would guess) a set number of channels you have the option of looking at either a multitrack mixer such as non-mixer or a set of stereo racks. I would put all the possible effects in line but have the ones not used bypassed... at least I would try that. This is so that it is easy to set up a midi controller. I suppose I should also ask if you are going to do any of your own coding to glue this together. You will probably at least need some shell scripts to set things up unless you will have some sort of UI that will allow manually setting this up every time. Another question... Will X run? Or will you be running all CLI? Without a track count, it is hard to know. multitrack could be 4 or 24 tracks. Even then, it would be hard to tell as I have found changing parameters within a plugin can change cpu use of that plugin. Of course knowing what latency your IF is capable of and the latency you intend to use is important too. It would be pretty easy to say that a dual xeon board would handle it, but then one of the new 8 core atom boards may work just as well... note: I don't know how far a single audio chain can be split over cores. WRT reverb: Do you really want each track to have it's own reverb? Having one reverb (or two) service a number of tracks through sends is not only done to conserve CPU cycles. It also lets the sounds be in the same virual acoustic space. However, setting up the sasme reverb 5 times does allow each track to be dealt with separately. Another question: will you be mixing the outputs? (sometimes, never) What parts do you already have? What is your budget? What is your reason for wanting to do this in a computer rather than just buying something that has these things. By the time you buy the interface ($500 for 8 i/o), case, MB, CPU, memory, PS, HD, midi controller and PCIe card for the audio IF... you are getting close to the $2000 mark already. (this is noting that you said this is a one use box) You can buy a digital mixer with 16 channels already. You have said that there is not some effect that you want in particular, but generic effects. Look at: http://www.allen-heath.com/ahproducts/qu-16/ ~$2100 http://www.behringer.com/EN/Products/X32-RACK.aspx ~$1200 (Sweetwater) I am sure there are others too. This is not to say your project is not valid. I am just trying to make sure you have some perspective. BTW, the units I pointed out do not use one fast CPU, but a number of ARM and DSP units. If you already have most of the parts on hand... particularly if you have a spare computer even with only two inputs. I would try it out with that for two tracks so you have an idea of what sw is around. You can try more tracks than two by just setting them up, as jack does not care if inputs are physical or not. Playing back *.wav files does not take much cpu. I was able to do quite a lot with just an old P4 even at low latency, The new i5 already makes audio use much less cpu. (even with jack set 16/2) All of todays CPUs are beyond yesterdays super chips. -- Len Ovens www.ovenwerks.net