The AK4497 dac chip is as expensive as the ES9038PRO. So it has to be really really really good to be worth spending money on it.
Some of AK4497 and ES9038pro DAC's available has inferior housekeeping circuit around them. So they are in my opinion not worth the money.
Some of AK4497 and ES9038pro DAC's available has inferior housekeeping circuit around them. So they are in my opinion not worth the money.
Some of you have asked if i have a RIAA stage.
I have a very fine one that can compete with the DAC performance. It is very low noise and we have tried it on a Project turntable with Grado pickup.
I will make a limited series of it. It will be able to use any JE990 / 2520 compatible opamp module with JFET inputs. And it will of course be able to use my modules.
BR
Sonny
I have a very fine one that can compete with the DAC performance. It is very low noise and we have tried it on a Project turntable with Grado pickup.
I will make a limited series of it. It will be able to use any JE990 / 2520 compatible opamp module with JFET inputs. And it will of course be able to use my modules.
BR
Sonny
What is the difference between the PCM and DSD output shield ? Is it just the value of the low pass filter which is higher for the PCM ?
Actually the DSD requires higher filterorder than PCM. Which in turn higher phase shift in the audible range. Phase shift is easy to hear. Just in the same way as phase alignment of the speaker drivers.
Then if I listen both PCM and DSD (upsampled to 256x), should I get the DSD shield ?
But for practical use, the noise level from the AK4490 is okay low to use the PCM filter for DSD playback.
Is it possible to have the discrete shield set for DSD ?
Yes it is. You only have to specify it.
BR
Sonny
Actually the DSD requires higher filterorder than PCM. Which in turn higher phase shift in the audible range. Phase shift is easy to hear. Just in the same way as phase alignment of the speaker drivers.
Then if I listen both PCM and DSD (upsampled to 256x), should I get the DSD shield ?
But for practical use, the noise level from the AK4490 is okay low to use the PCM filter for DSD playback.
Is it possible to have the discrete shield set for DSD ?
Yes it is. You only have to specify it.
BR
Sonny
Ok, I'll take the bait too! Can you give a minimum timeline and approximate cost?
What would be used for powering it - the Linestage supply?
Regards - Steven
What would be used for powering it - the Linestage supply?
Regards - Steven
Thank you very much for your reply Sonny.
Also I have another question which I am pretty sure has already been answered but can't find the info :
Is the frontpanner compatible with the DAC alone (without the preamplifier) ? I guess YES, and so what controls does it permits on the DAC ? Can we select between the different digital filters, the DSD mode (bypass of volume and delta-sigma modulator), and External Digital Filter mode ?
Thanks
So, I've managed to get it hooked up. I have the case opened and I see that the BD139/140 BJTs on the discrete preamp as well as the diodes with the heatsink on the LPS v2 are in the high 70 degree celsius range. Is this a safe temperature to operate at in the long term?
The other parts are maybe in the 50-60 degree celsius range. Ambient temperature is maybe about 28 degrees celsius.
The other parts are maybe in the 50-60 degree celsius range. Ambient temperature is maybe about 28 degrees celsius.
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You wrote:
Also I have another question which I am pretty sure has already been answered but can't find the info :
Is the frontpanner compatible with the DAC alone (without the preamplifier) ? I guess YES, and so what controls does it permits on the DAC ? Can we select between the different digital filters, the DSD mode (bypass of volume and delta-sigma modulator), and External Digital Filter mode ?
Answer:
The frontpanel can be used with the DAC alone.
1) Can we select between the different digital filters - Yes
2) the DSD mode (bypass of volume and delta-sigma modulator) - Yes
3) and External Digital Filter mode ? - No
I have attached the RIAA curve. It looks wavy curve but look at the left scale and you will see it is within 0.2dB.
It uses two of the modules per channel as the one shown below. It is 2520 pin compatible. So the design is safe for several years as there is several modules on the market in 2520 design.
I have one task that I need the help from the forum on.
We need the following caps:
They all have to be better or equal to 5% tolerance.
Per channel
3 x 100nF or 2 x 150nF
1 x 100nF
2 x 15nF (FKP2 2.5% 5mm pitch)
1 x 10nF (FKP2 2.5% 5mm pitch)
---
Power requirement is 160mA and +/-15V +/-1V tolerance
The board alone will without caps cost 107€
The 4 modules when purchased with the board cost 63€ each but a package with the board and 4 of the modules will cost 307€
I can get good claritycaps to a decent price. but i need to make sure that we can order enough. Best prices will be if i could get somewhere near 10 boards.
BR
Sonny
Attachments
Or alternatively i could just use MKP1837/KP1830/FKP2
It will only be a few euros more and i could include it in the price.
BR
Sonny
It will only be a few euros more and i could include it in the price.
BR
Sonny
Okay here is the deal:
we have 15 pcs of RIAA modules:
Quote:
Originally Posted by rogerchou View Post
Hi Sonny,
Would you mind talk about the specifications in detail?
I have attached the RIAA curve. It looks wavy curve but look at the left scale and you will see it is within 0.2dB.
It uses two of the modules per channel as the one shown below. It is 2520 pin compatible. So the design is safe for several years as there is several modules on the market in 2520 design.
Caps are Vishay MKP1837,KP1830 and WIMA FKP2
Power requirement is 160mA and +/-15V +/-1V tolerance
The board alone will with caps cost 111€
The 4 modules when purchased with the board cost 63€ each but a package with the board and 4 of the modules will cost 311€
The RIAA curve with MKP1837/KP1830/FKP2.
we have 15 pcs of RIAA modules:
Quote:
Originally Posted by rogerchou View Post
Hi Sonny,
Would you mind talk about the specifications in detail?
I have attached the RIAA curve. It looks wavy curve but look at the left scale and you will see it is within 0.2dB.
It uses two of the modules per channel as the one shown below. It is 2520 pin compatible. So the design is safe for several years as there is several modules on the market in 2520 design.
Caps are Vishay MKP1837,KP1830 and WIMA FKP2
Power requirement is 160mA and +/-15V +/-1V tolerance
The board alone will with caps cost 111€
The 4 modules when purchased with the board cost 63€ each but a package with the board and 4 of the modules will cost 311€
The RIAA curve with MKP1837/KP1830/FKP2.
