Reaktor5 CPU spikes on a 8x3.2Ghz core MacPro

Hello
I'm getting to grips with Reaktor 5 on an 2xQuad core 3.2Ghz Intel Mac Pro with 16GB RAM.

I create a new instrument from scratch as following the manual, ADSR, Triangle wave gen, f Cutoff, Reson and a 4pole filter. Nice and simple.

The instrument registers 2.2% on the reaktor cpu reg. Play a few bars, all good. I've got a Behringer BCR2000 plugged in for midi control and an a33 midi keyboard.

Sample rate 96Khz, Control rate a reasonable 800Hz.

If I call up the recorder, and go into record mode, Reaktor is flicking between the 2.2-2.8% CPU and OVERLOAD. If I up the sample rate to 384Khz I get a Chernoble geiger counter in my ear. But, ok I think, lower to 24Khz and start from there, but I'm still getting overloads - I surely shouldn't with this CPU power.

Anyone seen this before? Naturally I don't suspect my mac given the CPU palette of the O/S is showing the CPUs are basically bored so why am I getting clicks in my ears when it overloads? ie, why is it overloading? I've checked the setup a couple of times but am new to R5.

Any help gratefully received.
s

 

Welcome =)

1) Update to 5.1.5 if you haven't
2) Reaktor wll only use one core; it (like 95% of the plugins/instruments out there) doesn't multithread due to latency considerations. Core/thread distribution takes time
3) Speedstepping. Macs speedstep, and drastically. You can either wait for Snow Leopard to come out (which addresses speedstepping and HT issues) or use Coolbook, QuietMBP or some other form of kernel extension designed to control CPU speed. Note that using any kernel extension to control speedstepping is an at your own risk solution, due to higher operating temperatures and the like.

ew

 

an important thing to remember here is that the Recorder only records at 44100 Hz,
so there is really no point in having your Sample Rate any higher.

also the Recorder is a bit buggy anyway, so you get glitches when recording but they seem to be better on playback.

my advice, either use the Reaktor Tape Maschine - there is a Stereo File Recorder listed in your Instruments - or record Reaktor's Audio in your DAW.

sowari

 

thanks for the swift replies guys. interesting stuff. i'm on 5.1.5.
i bought my MP souped up to handle video and audio simultaneous and although reaktor using a single core only gives more for other simultaneous apps, it would be nice to be able to have a bit more freedom.

ew - when you say core/thread distribution takes time, are you suggesting the reaktor dev team are looking at or actively developing the app such that it will handle multiple cored boxes?

sowari, cheers for the info; i'll get my 1-cpu hat on and turn everything down - i was only using the recorder as a cheap way to experiment before i got to the bit in the manual about using instruments as plugins to logic pro..

if reaktor standalone only uses 1 core, if i plugged in multiple reaktor instruments into my multi-core handling DAW (say, logic), would that be a way round to getting different reaktor instruments working on different cores, or would it depend on the DAW?

hope that makes sense.
TIA
s
---
i've just turned the sample rate of reaktor down to 24Khz, and the control rate to 25Hz and I'm still hearing glitches on ensembles when i insert any one of the supplied synths into a new ensemble, if i had glitches from operating another instrument at a sample rate too high.

i notice that if i restart reaktor it goes away until i push up the sample freq again. then no matter what i swap the instrument for, i get the glitches hanging around til i restart reaktor.

even on one 3.2GHz core it seems a bit frustrating to have to run it on the bottom rung and hope i don't have to restart. i guess until snow leopard this is the best way?

s

 

Speedstepping was an issue on my Dell laptop, and it caused the problems you describe. The OS, or firmware, or whatever, figured out it didn't need to run at full speed and regularly choked the clock. Instant overload and glitch. I finally found and loaded a utility that forces the CPU to run at full speed all the time, and haven't had a problem since.

If Macs do that too, it may be your problem.

 

I couldn't say if they are or not. I was speaking about processing time; the app would require about 5 ms or more to handle thread distribution; this is in addition to your normal latency. See the problem?

Yeah- use multiple instances. Logic will distribute instances among the cores.

You didn't even need to do that. All you had to do is set your power scheme in Windows to always on (XP)/maximum performance (Vista). Unfortunately, with Macs at the moment, you need the third party kernel extension- unless you're running it as a Windows box.

It almost definitely is...

ew

 

Unfortunately, I'm still getting glitches on playback, so I prefer using my DAW to write, for example, demo sounds for synth or something like that. I'm on Mac Book 2.2 Core Duo.

 

ew I see immediately what you mean. still, with logic pro 8 capable of using all 8 of my cores, i'll use reaktor instruments as plugins and that should help matters (i'd read in the user library that instruments behave better in this environment).

thanks for your help. roll on sept 09 so i can get snow leopard. now all i need to do is work out how to render instruments and ensembles as plugins in logic..