NVGate DSP computation SPU

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Normal DSP

SPU computation for normal DSP : OR34 V1 - Or35V1 - OR36V1 OR36V22 (normal DSP) - OR38V1 - OR38V2 (Normal DSP).

Because of the linearity of the computation, we consider 1DSP = 12 SPU. This allow a simplification for SPU computation. So we can deduce:

FFT

Computation SPUs:

Bandwidth Fdec Resolution Envelope Zoom SPU/Channel
for Real-time
SPU/Channel
for non Real-time
20k 1 401 No No 1 0,5
10k 1 401 No No 0,5 0,25
Nk 1 401 No No =N/20 =N/40
10k 2 401 No No 1 1
5k 4 401 No No 0,8 0,6
2k 10 401 No No 0,6 0,6
1k 20 401 No No 0,5 0,6
Lower
than 1k
Higher
than 20
401 No No 0,5 0,5
20k 1 401 and
below
No No 1 0,5
20k 1 801 No No 1,25 0,5
20k 1 1601 No No 1,5 0,5
20k 1 3201 No No 2 0,5
20k 1 6401 No No 3 0,5
20k 1 401 No No 1 0,5
20k 1 401 No Yes 2 1,5
20k 1 401 No No 1 0,5
20k 1 401 Yes Yes 3 3



SOA

Computation SPUs:

Bandwidth (Hz) Decimation factor Resolution SPU/Channel
20 k 1 401 3
10 k 1 401 1,5
N k 1 401 =(N*3)/20
10 k 2 401 2
5 k 4 401 1,3
2,5 k 8 401 1,1
1,25 k 16 401 0,9
625 32 401 0,8
313 64 401 0,7
156 128 401 0,6
78 256 401 0,6
20 k 1 401 and below 3
20 k 1 801 3,25


Sampling Frequency: set in Front-End/Inputs settings/Input sampling

FFT Bandwidth: set in FFTx/FFT analysis/range

==

Octave:

Bandwidth Fdec Reso SPU/Channel
for Real-time
25.6k 1 1/3rd 4
20k 1 1/3rd 3
12.8k 1 1/3rd 2
10k 1 1/3rd 1,5
20k 1 1/3rd 3,0
10k 2 1/3rd 2,0
5k 4 1/3rd 1,25
20k 1 1/1 1,5
20k 1 1/3rd 3
20k 1 1/12th 6
20k 1 1/24th 12


Sampling Frequency: set in Front-End/Inputs settings/Input sampling

1/N Oct Bandwidth: set in OCT/FFT analysis/range

OVA

Bandwidth SPU/Channel
for Real-time
25,6k 1,25
20k 1
12,8k 0,75
10k 0,5

The overall acoustic levels analysis requires 1 SPU per channel at 20 kHz bandwidth. The number of required SPUs is directly proportional to the analysis bandwidth (i.e. the sampling frequency divided by 2.56).


Force DSP