DEQX users ...

[PeterSt]

One of the disadvantages IMO of the DEQX is that its digital input determines the number of bits it uses for its internal processing. Thus, where it seems that CDPlayer -> DigIn-DEQX(DAC) -> AnOut-DEQX is best, Analogue-In really should be better for overall results because then it uses maximum bits for its internal processing.

Of course, both internal 16 bit processing and DCPlayer -> DAC -> (ADC)AnIn-DEQX(DAC) -> AnOut-DEQX come down to a huge compromise.

Now please keep in mind that when you set XXHighEnd to "DAC needs" to 32 bits and you feed that DigIn to the DEQX, it will apply internal 32 bit processing.

Peter

[Telstar]

Agreed.

I think in the future the way to go is to use the computer for EQ purposes
And the good part is that there are free programs that do that.

[modmix]

Hi Peter,

I use a DEQX since quite a while (sources so far: various sw player, media player and sat-receiver; all connected via AES/EBU through 10 MHz sync-ed MC-3+ re-clocker - quite happy with that ,-)

I just discovered these page while looking around for some information related to perceived SQ differences.

Now please keep in mind that when you set XXHighEnd to "DAC needs" to 32 bits and you feed that DigIn to the DEQX, it will apply internal 32 bit processing.

Would you pls kindly explain this a bit more?
DEQX digitally receives SPDIF or AES/EBU, only. Both signals may carry up to 24 bit per sample, as far as I know.

Thank you in advance
Ulli

As a side remark: A/D conversion inside DEQX uses an internal oscillator with some limited spec - SQ has been improved by a friend by changing this device.

[PeterSt]

Hi there Ulli,

SPDIF/EAS can just "transport" 32 bits all right.
So what I recall further (but this is a LONG time ago !) is that the internal processing of the DEQX relies on the received bit depth. And, as I can derive from my original post, when you'd use a CD player for source (or any software player for that matter) which outputs in 16 bits, the DEQX will process with 16 bits as well. Not the best ...

But please notice, this is from such a long time ago that I can imagine that the modern DEQX works all differently.
But of course you can easily try : just use a software player that outputs in 32 bits and compare with one that outputs in 16 bits.

I hope this helps and best regards,
Peter

[modmix]

Hi Peter,

SPDIF/EAS can just "transport" 32 bits all right.

Not all SPDIF bits may carry audio bits...
BR
Ulli


From http://en.wikipedia.org/wiki/S/PDIF :

S/PDIF is meant to be used for transmitting 20-bit audio data streams plus other related information. To transmit sources with less than 20 bits of sample accuracy, the superfluous bits will be set to zero. S/PDIF can also transport 24-bit samples by way of four extra bits; however, not all equipment supports this, and these extra bits may be ignored.

More details eg. on http://en.wikipedia.org/wiki/AES3:

At the highest level, data is issued as consecutive audio blocks; each audio block consists of 192 consecutive frames. Data contained in each frame is collated into metadata for every audio block.

A 64-time-slot frame is issued each sample time; this fact determining the clock rate. The frame is divided into two 32-time-slot subframes each containing one sample; the subframes are used for the channels: A (left) and B (right). Each subframe consists of 32 time slots each of 2 symbols comprising either 1 bit encoded with biphase mark code or synchronisation preamble. In each subframe, audio data may use up to 24 bits.

The 32 time slots of each subframe are used as following:
...
8–27, or 4–27    Audio sample
...

[PeterSt]

Hi Ulli,

SPDIF/EAS can just "transport" 32 bits all right.

You didn't understand, or maybe better to say : you look in too much detail while you should be in a helicopter.

When I, as a software player developer, send 24 bit audio data or 32 bit audio data, I am not interested what any hardware layer is going to make of it. In other words, what you showed in those pictures is not necessary to know for me at all. I just send 2x 32 bits for stereo. Or for example 8x DTS encoded channels. And yes, over SPDIF.
Notice that DACs almost always work with 32 bit audio words per channel, hence 64 bit for stereo. This is because i2s is like that.

It is only since USB that DACs started to work with 24 bit words as well because of bandwidth limitations.

Btw, did you try it ?
Regards,
Peter

[modmix]

Hi Peter,

I don't like helicopters...
I'm pretty sure that the hardware layer does have some impact on SQ.
So we agree not to agree, I hope ,-)

Of course I've done several experiments with 16 or 24 bit coded music. Results as expected. No 32 bit available, though.

Cheers
Ulli