How did you get the 8V shunts? Tentlabs site lists only 3.3/5/15V versions.
Contact Tentlabs with your requirements and he will make them for you. I have some on order with him.
WaveIO 384KHz Upgrade
So, I've upgraded the WaveIO board to 384KHz capable and changed my LCD logic to display the new rate. Downloaded some 2L sample DXD files and they play OK and LCD shows correct sample rate using JRiver for Mac (with no sample rate conversion).
However, I thought the PCM1794A was limited to 200KHz sample rate max. So what is actually playing ? Or have I mis-interpreted the data sheets ?
Is the WaveIO accepting the higher sample rates but downsampling ?
Is the PCM19794 accepting the higher rates but downsampling?
Or is the DAC actually playing at the 384KHZ sample rate ?
Any clarification gratefully received !
Post amendement - quote as per WaveIO forum:.
"No There are NO sound processing techniques involved here as long as I'm aware off. If you'll play 32/384 KHz music file then WaveIO will output the streams at 32/384 KHz but it depends on your DAC how will handle the extra bits of data. WaveIO's output protocol (I speak about I2S ports) is a standard 64fs I2S one so, for a 24 bit resolution music file, it will output 24 bits starting with MSB first and fill the rest of extra bits with zeroes. Same for 16 bits but I didn't personally test the configuration (so theoretically I can be wrong ). As I said, it all depends on your DAC chip and how it will handle the entire I2S bus signals...
I hope it helps,
Lucian"
So I presume the PCM1794 handles the higher sample rates in some way. Anyone know definitely ?
AudioH
So, I've upgraded the WaveIO board to 384KHz capable and changed my LCD logic to display the new rate. Downloaded some 2L sample DXD files and they play OK and LCD shows correct sample rate using JRiver for Mac (with no sample rate conversion).
However, I thought the PCM1794A was limited to 200KHz sample rate max. So what is actually playing ? Or have I mis-interpreted the data sheets ?
Is the WaveIO accepting the higher sample rates but downsampling ?
Is the PCM19794 accepting the higher rates but downsampling?
Or is the DAC actually playing at the 384KHZ sample rate ?
Any clarification gratefully received !
Post amendement - quote as per WaveIO forum:.
"No There are NO sound processing techniques involved here as long as I'm aware off. If you'll play 32/384 KHz music file then WaveIO will output the streams at 32/384 KHz but it depends on your DAC how will handle the extra bits of data. WaveIO's output protocol (I speak about I2S ports) is a standard 64fs I2S one so, for a 24 bit resolution music file, it will output 24 bits starting with MSB first and fill the rest of extra bits with zeroes. Same for 16 bits but I didn't personally test the configuration (so theoretically I can be wrong ). As I said, it all depends on your DAC chip and how it will handle the entire I2S bus signals...
I hope it helps,
Lucian"
So I presume the PCM1794 handles the higher sample rates in some way. Anyone know definitely ?
AudioH
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WaveIO Upgrade
Thanks for the confirmation Doede. I was hoping that was the case.
Another benefit of the WaveIO upgrade is that DSD files can now be played, as PCM of course. JRiver MC 18 converst DSD to PCM:
"The DSD to PCM conversion process converts from 1-bit DSD to 64-bit PCM at 1/8th of the sample rate. The total amount of data from this conversion grows by 8x, so the process is effectively lossless / perfect.
Once you have PCM, it will be 64bit @ 352.8 kHz for DSD, and 64bit @ 705.6 kHz for DSD 2x. "
Best Regards
Thanks for the confirmation Doede. I was hoping that was the case.
Another benefit of the WaveIO upgrade is that DSD files can now be played, as PCM of course. JRiver MC 18 converst DSD to PCM:
"The DSD to PCM conversion process converts from 1-bit DSD to 64-bit PCM at 1/8th of the sample rate. The total amount of data from this conversion grows by 8x, so the process is effectively lossless / perfect.
Once you have PCM, it will be 64bit @ 352.8 kHz for DSD, and 64bit @ 705.6 kHz for DSD 2x. "
Best Regards
Not 100% certain but I think the full WaveI/O only has SPDIF out. You will need a SPDIF > I2S board. I use the one Doede has on his website here:
DDDAC 1794 NOS DAC - Non Oversampling DAC with PCM1794 - no digital filter - modular design DIY DAC for high resolution audio 192/24 192kHz 24bit
Bas,
The standard Wave io has three outputs: i2s isolated ground and unisolated ground and spdif.
Wave io input is only USB.
Doede sells a lower priced version without the spdif output parts mounted because they will not be used for his dac (and sound not so good as i2s)
So you would need something Ian proposed.
The standard Wave io has three outputs: i2s isolated ground and unisolated ground and spdif.
Wave io input is only USB.
Doede sells a lower priced version without the spdif output parts mounted because they will not be used for his dac (and sound not so good as i2s
)So you would need something Ian proposed.
Thanks surfer. I've sold the guy one of my previous dacs. So I don't need spdif anymore. He'll have to get with the USB program before he is allowed to listen to the real McCoy
That will teach him!
USB and I2S rule You know there are still people who use optical connections. Oh yes; and even those who use these real big black round plates with holes in the middle
Supersize me! - transformer
There is a thread in audio-asylum on experiences with larger than required transformers- see RE: Power Supply Upgrade Results - drlowmu - Tweakers' Asylum.
My power supply arrangement using choke input supply and other enhancements have been detailed in posts 275 and 285.
My curiosity got the better of me and I tried changing my current 30 VA amp rated transformers to the following- USB board supply increased to 120 VA using four identical 30VA txrs in parallel; the dac supply replaced existing one with almost same sec voltage but with 12A current rating ( that is total 300VA rating).
On listening through the same set up another jump in sound quality.
Doede and others, if you have spare transformer, try this out and check for yourselves. There is still unexploited potential in improving sound quality - all this on std CD quality from my laptop.
I am still perplexed why this should be so! With choke input, theoretically this should make no difference.
Encourage others to try with spares in the bin. It will be an interesting journey!
Cheers!
There is a thread in audio-asylum on experiences with larger than required transformers- see RE: Power Supply Upgrade Results - drlowmu - Tweakers' Asylum.
My power supply arrangement using choke input supply and other enhancements have been detailed in posts 275 and 285.
My curiosity got the better of me and I tried changing my current 30 VA amp rated transformers to the following- USB board supply increased to 120 VA using four identical 30VA txrs in parallel; the dac supply replaced existing one with almost same sec voltage but with 12A current rating ( that is total 300VA rating).
On listening through the same set up another jump in sound quality.
Doede and others, if you have spare transformer, try this out and check for yourselves. There is still unexploited potential in improving sound quality - all this on std CD quality from my laptop.
I am still perplexed why this should be so! With choke input, theoretically this should make no difference.
Encourage others to try with spares in the bin. It will be an interesting journey!
Cheers!
Hi Bravi,
Yes this works.
This has all to do with lowering the supply impedance. There are more ways of providing a low power supply impedance that lead to similar sound improvments. I have gone the route of shunt supply (even on the dac boards) with very good results.
In most audio designs there is a lot to gain with improving power supplys, don't forget that the sound you hear comes directly from your wall socked; an amplifier is nothing more than a modulating power supply..................
As power = voltage x current, a tube amplifier has also an advantage over transistors due to the higher voltage present at the anodes. Voltage is always present at the anode, but current has to flow from your wall socket to the amplifier. Think about the impact on dynamics for a moment.
I think in Europe we also have an advantage because of the 230v wall wart voltage.
This is probably also the reason why Doede has upped the voltage to the analog supply on the dac chips from 5 to 8 volts; gaining dynamics.
Regards,
Yes this works.
This has all to do with lowering the supply impedance. There are more ways of providing a low power supply impedance that lead to similar sound improvments. I have gone the route of shunt supply (even on the dac boards) with very good results.
In most audio designs there is a lot to gain with improving power supplys, don't forget that the sound you hear comes directly from your wall socked; an amplifier is nothing more than a modulating power supply..................
As power = voltage x current, a tube amplifier has also an advantage over transistors due to the higher voltage present at the anodes. Voltage is always present at the anode, but current has to flow from your wall socket to the amplifier. Think about the impact on dynamics for a moment.
I think in Europe we also have an advantage because of the 230v wall wart voltage.
This is probably also the reason why Doede has upped the voltage to the analog supply on the dac chips from 5 to 8 volts; gaining dynamics.
Regards,
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Hi Supersurfer,
Do you by any chance have spare transformers in your bin to try an experiment? If you have some with a similar voltage to the one you have powering the shunt regs, try paralleling to them so that you have at least 2 or 3 times the VA and see if you hear any difference.
The suggestion is made since a choke input supply designed for critical current flow should not have any difference just by increasing the current rating of the power transformer ( By the way I was running it at only 35% capacity, well below the possible utilisation for a choke loaded supply). But it seems that even though the sec voltage is the same and the rectified voltages are the same, the improvement in sound quality is quite obvious.
Cheers!
Do you by any chance have spare transformers in your bin to try an experiment? If you have some with a similar voltage to the one you have powering the shunt regs, try paralleling to them so that you have at least 2 or 3 times the VA and see if you hear any difference.
The suggestion is made since a choke input supply designed for critical current flow should not have any difference just by increasing the current rating of the power transformer ( By the way I was running it at only 35% capacity, well below the possible utilisation for a choke loaded supply). But it seems that even though the sec voltage is the same and the rectified voltages are the same, the improvement in sound quality is quite obvious.
Cheers!