long loop (3:48) hangs Loop Machine in GR3

[enigmacs]

hi, i have looked thro the forum and the knowledge base and haven't found anyone having the same problem, so here goes...

i recorded a 3:48 loop (very long, i know -- it's a full song) on Tape Deck 1. i wanted to use this loop in the Loop Machine to record over it with vocals, etc.

then i tried to open the wave file in the Loop Machine. CPU maxed out, it took awhile, but finally opened. the beginning and the end were there, the middle was missing.

so then i tried to play it from Tape Deck 1 live, recording to the Loop Machine as the first loop. worked great for about 3:20, then the CPU maxed out again, and video seized up intermittently. but it finally finished, and actually sounded alright, too. then i tried to save the loop as an LS file -- CPU maxed out forever and i finally had to force GR3 to close.

i tried the same in the GR4 demo, hoping maybe the Loop Machine had been improved, but exactly the same results.

- i'm using the latest GR3 -- 3.2.1 -- on a Windows XP SP3 machine.
- CPU is a single core Intel Centrino M running at 1.7GHz.
- sound card is Echo Indigo io.
- i had latency set to 1024 samples.
- hard drive has 65GB free.
- 1GB of RAM but with shared video memory, it comes down to 0.99 GB.
- i was monitoring RAM the whole time and it never fell below 400MB available.
- i did all the tweaks for Windows XP -- even more because my hubby is a Flight Simulator X fan (building a cockpit in our family room) and he gave me 14 pages of tweaks to do to reclaim RAM and processing power.

the loop loads fine in the Tape Decks, and i have successfully recorded from one Tape Deck to the other and saved -- no problem at all. it seems to be a glitch with the Loop Machine.

i know my CPU is not fast compared to what's currently out there, but it should be enough -- the minimum required is 1.4GHz. also, my loop is long, i know, but the manual says that "loop duration is only limited by the size of your hard drive."

if anyone can offer suggestions, i would really appreciate it... thanx!

[enigmacs]

here's the response i got from Tech Support:

"The reality is that yes-you-can... but it really won't be smooth. You CPU is
just barley making it, considering how much the system's footprint is on RAM.
Basically anything in Ram must be processed, so with that in mind please
remember that the system will use all the Ram available, then virtual paging
occurs... the CPU spike. I would max out the RAM on your system. Thumb rule is
that the more effects the more RAM is being used for calculations. This can
help. But it will still be a little sluggish opening."

so i'm going to max out my RAM and see how that goes...

[enigmacs]

'kay, so nobody seems to have any help for me still...! am i the only one doing long loops in the Loop Machine?

anyways, i maxed out my RAM to 1.5GB -- an increase of half a gig. that's all my laptop can handle.

and there was no noticeable improvement. Loop Machine behaved EXACTLY the same as before.

if anyone has a clue, please share it with me. all i can think now is that i need a more powerful CPU.

[Fill Brisell]

Hmm - it would / will be interesting to see who is cheating who here. When I bought GuitarRig 2 the Looper was spanking new, and marketing then boasted that you now could have loops as long / large as your harddisk permitted. Yes: hour-long loops. Now tech support says you can't even use minute long loops really. Who inside NI are lying?
I checked and it appears a 3 min long loop at standard 16-bit 44.1 kHz will need about 31 Mb of memory. That shouldn't make your system trip at all, of course. Doing some simple programming myself, I suspect that the Looper application will reserve much more memory for itself than that; perhaps say 8 x the size of the loop loaded. This way it can handle eight layers without caching to disk. In your case 31 mB x 8 = 248 mB. This figure (which is just a suggested number from my side) may be what the Looper really needs as a minimum for itself to run smoothly. This may explain why it hits the limit on your system. On another side, if this is the case, then it isn't very fantastic programming.
I haven't used the Looper much I must admit; I don't use much looping for guitar, and when I do I use the free Moebius Looper.
My laptop specs are even weaker than yours, and I will try it. When GR2 came out my laptop specs were pretty hot, and then NI said you could play hour long loops. Hmm . . .

[enigmacs]

thot i'd try it again (recording my 3:48 loop from Tape Deck 1 to Loop Machine), this time keeping a close eye on my % CPU being used by GR3 in the Windows Task Manager.

here's what i found:

for the first 3:20 (approx.), the Task Manager reported GR3 %CPU fairly steady, wandering about between 19 to 35% CPU. meanwhile, GR3 reported a steady 16% CPU usage (top right corner of GR3).

then around 3:20, there was a very SUDDEN CPU spike right up to 100% -- and it continued up at 100% until i stopped the Loop Machine.

i am not a technical expert here, but i am surprised at the sudden spike -- i would have expected it perhaps to increase gradually until it was overwhelmed. the sudden spike suggests to me that there is some kind of glitch button that gets pushed at 3:20 for some strange reason.

just for info: my 3:48 loop is 128MB at 4608kbps Bit Rate.

and this is from the current official product info for GR4 Pro:

"The loop duration is only limited by the size of your hard disc – theoretically you can layer loops for hours."

it seems to me that the CPU staying around 19 to 35% is the expected behaviour. i see no reason for a sudden spike at 3:20.

(must check out the Moebius Looper...)

[enigmacs]

argh! cannot make head or tail of Mobius Looper!

please, NI, get the Loop Machine working! it's such a beautiful thing!

[enigmacs]

tech support told me they think it might be my front-side-bus -- which is 400 MHz on my Gateway MX3563 laptop.

i tried it on my desktop - Intel Core 2 Duo running at 2.53 GHz with 3 GB RAM.

similar behaviour when i go from Tape Deck 1 into Loop Machine, EXCEPT:

before 3:20 it stays around at 11% CPU
after 3:20 it jumps up to 61% CPU suddenly and is able to finish

also, opening the 3:48 WAV file in the Loop Machine can be done in a matter of seconds with the faster CPU.

so... sadly... it looks like i need a faster laptop...