Is there a simple way to convert lots of older projects from 44.1 to 48khz?

1. Turn off internet, and any wi fi...(free up irq's)
Make sure you have onboard audio on...but not HD HDMI audio.
 
Setup/Control pannel/Speaker..Default play back device being the Onboard sound card,(share the device with mutilple software if you want to) and select the ins and outs of that device for playback...Play the 44.1 16bit file (Project?..stereo file?..))  through a  Media player, or software, other then Sonar///...Once you got 44.1 16 bit files playing through that onboard sound card, and coming out of the output jack.....Set up sonar to use the other audio device's ASIO? ((Tascam US1641 inputs)), and not share with any other software the ASIO....In Sonar's preference.
 
Then Run the software playing 44.1 file's output of the onboard sound cards play back, into the Audio card of added on ASIO input((Tascam US1641))....and re-record the file at your bit depth of choice/tempo and time signature does not need to change to do this, and....Should do the trick.
 
Do you have a second pc?...Play the file on one PC or Mac...take the output, run it into another PC's input, and record at the new bit rate....use the same tempo and time signaturess.....Should work...could even add eq through a mixer to beef it up...or feed a multi External FXs unit from one audio device...take the output of that fx, and run it into the other audio device, and start recording... to re record...at ...etc
 
Or open a software that renders into multiple formats and rerender to the new bit rate....
 
Going from a lower bit rate to a higher might give you artifacts on the wav file....So I recommend re recording...and perhaps adding some eq if  necessary... 
 
Some say to capture the best sound, others say capture the best performance....I say "" get it done.."" and it is done!
 
Best wishes!

Brundlefly made a nice post a week or two ago on the conversioning. I will not be able to find it on my phone for you though :(

There are so many programs and tools which can batch-convert WAV from 44 kHz to 48 kHz.
Batch-convert ALL files from 44 to 48 kHz OUTSIDE of Sonar.
When you start any Project it is fully converted.
This takes only ten minutes of time to convert ALL wav-files from all your projects.
 
For example:
http://www.fmjsoft.com/awaveaudio.html
http://www.avs4you.com
 

Thanks to all! Whoohoo.
@ Craig     I guess I'm thinking it's "better". I stayed with 44.1 when 48 became an option, because of limited HDD space (10+ years ago), and that isn't the case, now.  If my wife continues making videos, I'd like to do the soundtracks. I've read that 48 kHz is the "norm" in that world. I wouldn't be using all my projects, though, only some. So perhaps I could convert them as needed?
@ Sir Les    I do have 2 of each (PC+I/O), but that seems a PITA with 20-30 tracks per project. It is an option, tho.
@ Beep    That is the same "reading" that is floating around in my thought pool! "Didn't I read that....?"
@ Mettelus. Thanks, I'll look for his post.
@THambrecht    Thanks for those links. I wondered about that possibility.
Michael

I would listen to Beep on this. 

Hi, Les. Yeah... my dum dum understanding of frequency/samplerate stuff is 99% of the time the difference between 44.1 and 48 isn't gonna make any real difference... especially if most of the files were already recorded at 44.1. Upsampling? Well I don't know what can happen there but if I have something sounding good I try not to bounce/export/do anything to it unless necessary. I don't believe there is any benefit at all to increasing the sample.
 
But really I am indeed a dum dum and I work with an overabundance of caution simply out of fear because I don't want to screw something up.

Well, well, well! I didn't think about upsampling causing issues! I'll go with door #1, as Beep pointed out. It's fine as it is and I can do new stuff higher. No one mentioned whether downward conversion causes artifacts.... yes, no?
 
..and going back to video; I guess resampling my master mixes to 48khz wouldn't be a big deal, if I need to do that for a video.
Thanks to all.
Michael

Playing guitar is definitely more fun!
 
Do you hear a big difference at 96khz?
Michael

Well I think I can for certain things but I also think my hairline is exactly where it was when I was 18 and that chicks really dig scrawny, twisted up weirdo cripples.
 
So yeah... could be totally in my head. lol
 
Seriously though I've dropped to 48 and if I've lost anything it's minimal and I mix around it anyway. As I am learning more I may bump it up again for stuff I intend to fully release (for use in movies or whatever) but just for demos or fun stuff 48 is more than fine and what was used (AFAIK) in the ADAT days which was what the industry used for quite some time. No real reason to take the performance hit unless you have a specific need.
 
Bumping up from 44.1 for new projects would likely be a good idea though.
 
Cheers.

Didn't get to catch all of this thread, but Beeps' points are good ones. As I have only done a handful of videos, it is also simpler to work to completion (if in 44.1K) and then convert the master to 48K when the time comes for video work.