[Marius]

Hi Everybody,

trying to identify use and effect of the upsampling feature, I find it very difficult to hear substantial difference between cd-rips with or without upsampling. Could you point me to the difference in theory, but most importantly, point me to some recordings that benefit most from the upsampling?

up until now I've had varied advantages: for example, patricia Barber's Cafe Blue, really sounds much better through the BDA/BDP combo, Genesis' Seconds Out is amazing, where Peter Gabriel's Hit sounds rather less impressive, even thinnish on the combo, and far better through the BCD1...

with or without upsampling that is.Still trying to figure out what is the logic behind it all.

Thanks,
Marius

[Mag]

It's difficult to hear what upsampling does with good recordings. But with recordings from older cd's that aren't that good it makes a difference. Basically as I understand it, the Delta-Sigma conversion corrects the wave sample. On your typical cd as it is partially distorted. It won't however fix a bad recording.

Send me a message if interested in a sample cd.

[Phil A]

I would think if you upsample mediocre or crap, it is not going to improve it.  If you have a good source, then the upsample feature is not amplifying/upsampling the faults

[headshrinker2]

I have very mixed feelings about upsampling on the BDA-1.  On most recordings, I find it adds a smooth sonic signature that is slightly rolled off in the upper frequency range.  While not a dramatic change, it is not subtle to my ears.   It is a pleasing signature, but I find that it colors things across most recordings. 

At least to my ears, when I turn off upsampling, I find the air and space in the upper frequency range returns.   

[James Tanner]

UP-SAMPLING in BDP-1

After the input stage, the signal goes to the SYNCHRONOUS up-sampling circuit (sample rate converter). This circuit converts the digital signal from one sample rate and bit depth to another.

In the BDA-1, the sample rate is increased from the input sample frequency (32K, 48K, or 96K up-samples to 192K and 44.1K or 88.2K up-samples to 176.4K). The 16 bits of depth (the CD standard) is increased to 24 bits. The added 8 bits are filled with placeholder information. This up-sampling process provides a digital signal for later conversion to analog by the Crystal 4398 DAC chip. The up-sampling process doesn’t add any new, but does put the data in a form which can better be translated by the DAC as described below.

The advantage of this synchronous up-sampling process is improved processing of the up-sampled signal by the DAC chip, which was designed for higher sample rates and bit depths. There is also a noise shaping process implemented where “noise” within the audible spectrum is shifted up to frequencies above audible limits. An added advantage of this up-sampling process is that a totally new clock signal is applied, which results in significant jitter reduction.

[niels]

The B100 dac also upsamples, right? But it can only be turned on and off with the new remote.
On my old Philips dvd 963SA I couldnt hear a difference whether upsampling was on or off.

[Marius]

Thanks James, thats clear to me I guess...
So far for the technical side of things, but now the musical, audible side. How do I hear the advantages you describe? What kind of recordings benefit most?

Marius

UP-SAMPLING in BDP-1

After the input stage, the signal goes to the SYNCHRONOUS up-sampling circuit (sample rate converter). This circuit converts the digital signal from one sample rate and bit depth to another.

In the BDA-1, the sample rate is increased from the input sample frequency (32K, 48K, or 96K up-samples to 192K and 44.1K or 88.2K up-samples to 176.4K). The 16 bits of depth (the CD standard) is increased to 24 bits. The added 8 bits are filled with placeholder information. This up-sampling process provides a digital signal for later conversion to analog by the Crystal 4398 DAC chip. The up-sampling process doesn’t add any new, but does put the data in a form which can better be translated by the DAC as described below.

The advantage of this synchronous up-sampling process is improved processing of the up-sampled signal by the DAC chip, which was designed for higher sample rates and bit depths. There is also a noise shaping process implemented where “noise” within the audible spectrum is shifted up to frequencies above audible limits. An added advantage of this up-sampling process is that a totally new clock signal is applied, which results in significant jitter reduction.

[James Tanner]

Thanks James, thats clear to me I guess...
So far for the technical side of things, but now the musical, audible side. How do I hear the advantages you describe?

Marius

I like leaving things alone - so I always listen to the NATIVE sample rate - the rest is open to each individual.

james

[James Tanner]

The B100 dac also upsamples, right? But it can only be turned on and off with the new remote.
On my old Philips dvd 963SA I couldnt hear a difference whether upsampling was on or off.

Hi niels,

The B100 up-samples to 96/24 anything that is not native 96/24.  There is no way to turn it on or off.

james

[Marius]

Hi Headshrinker,

On which recordings you feel you can best hear the difference? I've got a feeling that I indeed hear a difference, but find it very hard to pin down as an improvement, and as a quality-of-sound-difference that is always the same, that is repeatable through various recordings. It might even stay a 'feeling', and I am not really sure it is 'better' or not. Not convinced yet.

what I'm trying to find out is whether for example old mono recordings, or 78-transfers as a rule benefit most, or wired radio-transmission (all those live Callas's ...), so that whenever I play something like that I hit the upsample automatically and enjoy.
Bottomline: when to use the upsampling feature?

I tend to stick with James's remark on listening to native formats, but why then did Bryston bother to add a upsample feature? Should be some musical relevance?

Marius

I have very mixed feelings about upsampling on the BDA-1.  On most recordings, I find it adds a smooth sonic signature that is slightly rolled off in the upper frequency range.  While not a dramatic change, it is not subtle to my ears.   It is a pleasing signature, but I find that it colors things across most recordings. 

At least to my ears, when I turn off upsampling, I find the air and space in the upper frequency range returns.

[niels]

I tend to stick with James's remark on listening to native formats, but why then did Bryston bother to add a upsample feature? Should be some musical relevance?

Marius

Hehe, maybe because if they left it out it wouldnt sell? Its a standard these days.

[robb]

Has anyone including Bryston made any measurements showing if the specifications change with and without upsamplinmg? Frequency response, distortion, square wave response, phase???

Rob