Caiman Mods

[StanleyB]

For those of you who are wondering which upsampling chip to use in any DAC you are designing for hobby purposes or otherwise, try the SRC4192 from TI. It doesn't need any special drivers.

All I now need is a driverless High Speed Audio USB chip. The only ones I can find details on all need drivers.

[leo]

Or the SRC4392 with built in receiver and ASRC

[leo]

For those of you who are wondering which upsampling chip to use in any DAC you are designing for hobby purposes or otherwise, try the SRC4192 from TI. It doesn't need any special drivers.

All I now need is a driverless High Speed Audio USB chip. The only ones I can find details on all need drivers.

They need to pull their fingers out with the high speed USB chips Stan

[StanleyB]

I have t agree with you Leo. I am very keen to try it out in a new DAC as soon as I can get my hands on any production sample.

[leo]

I have t agree with you Leo. I am very keen to try it out in a new DAC as soon as I can get my hands on any production sample.

Well if I find anything I'll let you know, surely it won't be too long now before somebody releases one

[StanleyB]

I have been receiving notifications of apparent production samples since 2006, but each of them got their limitation. One comes with free drivers, but only works on Windows.

[MartinT]

I have tried one of the TI chips, and found that the 64X oversampling Wolfson chip as used in the Caiman gives a far superior result that I prefer.

Stan, in what way is oversampling significantly different from upsampling? I would have thought the end result would be almost the same?

[StanleyB]

Stan, in what way is oversampling significantly different from upsampling? I would have thought the end result would be almost the same?

You could say that oversampling is equivalent to distilling alcohol, whilst upsampling is the equivalent of adding water to the alcohol until the bottle is full to the brim.

If you upsample a 44.1KHz signal to 192KHz you have to add 192 - 44.1 = 147.9KHz of extra data in the upsampled signal.

[MartinT]

I understand that, but isn't 64x oversampling adding 63 x 44.1kHz = 2.8M more samples?

[StanleyB]

The 64X oversampling is cutting the existing data into smaller sizes. Its the equivalent of modulating an audio signal with a high frequency carrier like in AM or FM. The decoded OS signal is still the same in shape as the original. An upsampled signal is a close approximation of the original, but not the same. The extra 0s added to stretch a 44.1KHz to 192KHz make a big difference. Get a digital storage scope and do some tests with waveforms through both methods of sampling. The theory is getting in the way of the practical outcome.