Comparison and test of CBR and VBR in speex coding broadband

According to the official website speex, in narrow cases, the performance of the speexvbr is equal to that of the speexcbr. As a result, the product test converts the original speex CBR into a speex VBR. But I don't know what the performance will be in the fuse. Compare speexcbr with speexvbr. I would like to share with you the following results. If there is any difference, please correct me.

PS: speexcbr uses the CBR protocol under the implied data.

Speexvbr1 indicates the VBR used in the use of the default value.

Speexvbr2 sets the highest quality and increases the bit rate to 40000bps.

1. For a layer-4 multi-core phonograph model, the audio usage is 16 kHz.

Zookeeper	Real bitrate after successful transfer
Speex CBR	3500*8 BPS
Speex vbr1	1580*8 BPS
Speex vbr2	2561*8 BPS

Comparison result: speexcbr> speexvbr2> speexvbr1

Speexvbr1 is clearly distorted and has a lot of noise.

Speexvbr2 is better than speexvbr1

Speexcbr is the best

2. for a person with more than one Shard, perform the following operations in this tutorial, so that the current sampling rate is 16 kHz.

Zookeeper	Real bitrate after successful transfer
Speex CBR	3500*8 BPS
Speex vbr1	1965*8 BPS
Speex vbr2	3172*8 BPS

Comparison result: speexcbr> = speexvbr2> speexvbr1

Sound quality is similar, VBR noise may be slightly more