The dac8812 is 2x16 spdt cmos switches. So it has no gain block! The gain block is discrete here. Pga2310 is no match here.
All inputs are switched through cmos switches. All outputs are switched through discrete SSR's
All resistors are Thin film 0.1%
So there is no cheap solutions here
Sent from my iPhone using Tapatalk
All inputs are switched through cmos switches. All outputs are switched through discrete SSR's
All resistors are Thin film 0.1%
So there is no cheap solutions here
Sent from my iPhone using Tapatalk
Hi Guys, can anyone recommend a high quality volume control or potentiometer for a Valve DAC output signal. That way I can avoid to use a pre-amplifier and control the output right there in a DAC.
Is there anything better than ALPS 27 ?
Many Thanks
Mykhailo
Is there anything better than ALPS 27 ?
Many Thanks
Mykhailo
Please find another place to ask like in the non commercial section. But i would suggest you DACT audio attenuators
BR
Sonny
Hi Sonny
I am reading through the dac8812 data sheet and a little lost to how this preamp works.
Is there any chance you can elaborate, whats happening to the signal?
Cheers
Seb
I am reading through the dac8812 data sheet and a little lost to how this preamp works.
Is there any chance you can elaborate, whats happening to the signal?
Cheers
Seb
Thanks Sonny for the explanation!
This looks like it will be a killer preamplifier!
Any pictures for us? 😀
Ciao!
Do
This looks like it will be a killer preamplifier!
Any pictures for us? 😀
Ciao!
Do
Would someone mind posting the appropriate wire housing plus terminals for use with the 5-position output on the discrete board? Maybe even a Mouser p/n, perhaps? I'd really appreciate it.
Regards,
John
Regards,
John
If you're referring to the audio line out, here it is. Those are Digikey parts but you can cross reference with vendor part #.
2 pin Molex KK .100 plug housing - Digikey : WM2000-ND
3 pin Molex KK .100 plug housing - Digikey : WM2001-ND
Molex KK .100 crimp terminal Tin - Digikey : WM1114-ND
Molex KK .100 crimp terminal Gold - Digikey : WM2312-ND
You cannot use a 5 pin Molex since they're two independent sockets.
Thanks for the part numbers, and thanks for including them in my shipment. I appreciate it.
Regards,
John
Regards,
John
All,
Thinking of getting this DAC but there is 2version of the PCM shield. Not sure which I should get.
What's the difference between the discrete DIFF/SE shield and SE shield? The difference is quite a bit @ 60+euros.
I will mostly use foobar outputting FLAC/APE to the DAC and I will also explore pi2/i2s volumio.
The output of the DAC will be connected to an integrated amp or a passive attenuator/tube amp.
Appreciate your help/advice to a noob.
Thinking of getting this DAC but there is 2version of the PCM shield. Not sure which I should get.
What's the difference between the discrete DIFF/SE shield and SE shield? The difference is quite a bit @ 60+euros.
I will mostly use foobar outputting FLAC/APE to the DAC and I will also explore pi2/i2s volumio.
The output of the DAC will be connected to an integrated amp or a passive attenuator/tube amp.
Appreciate your help/advice to a noob.
Hi, The difference on the DIFF/SE Shield and SE shield, is due to the use of opamps on the SE shield where DIFF/SE is purely discrete. Relays is replaced by Discrete SSR which sound superior to the relays.
I will remove the option DSD filter from by product catalogue. The reason is that the 2. order PCM filter has less impact on the signal than the 3. order DSD filter
You can listen to DSD and PCM (WAV/FLAC/ALAC/AAC/MP3) files with the PCM filter and they will both sound great.
BR
Sonny
Discrete Preamp to be used with DAC and Frontpanel.
Just to give you all an teaser. I will of course make an seperate thread for the Discrete preamp but here is an picture of the PCB.
The board has servo but also in this case we have decided to use an discrete approach. The servo can pull the output with +/-20mV. It is mainly the JFET vgs mismatch that sets the limit here.
The price for this board is 389€. To get it functioning it needs the frontpanel and +5.5V,+15V and -15V supply
Just to give you all an teaser. I will of course make an seperate thread for the Discrete preamp but here is an picture of the PCB.
The board has servo but also in this case we have decided to use an discrete approach. The servo can pull the output with +/-20mV. It is mainly the JFET vgs mismatch that sets the limit here.
- Discrete Servo
- JFET input discrete opamps
- R2R DAC 16 bit.
- +12dB Gain
- 5 channel DIFF/SE input
- Balanced output.
- No relays, only MOSFET switches.
- All stages runs in class A.
- Small size : 140x100mm
The price for this board is 389€. To get it functioning it needs the frontpanel and +5.5V,+15V and -15V supply
Attachments
Hi Sonny this is intrigying now looks like by the time I would be ready to start the assbly you would be offering the full set.
I have tow questions.
Would there be a separate volume control required for the pre amp to work ? If yes, what the impedance should be.
You are saying that pre amp would fit the DAC, meaning AK DAC right ?
On the other hand it has an r2r dac, would there bea n option to choose and external DAC or the internal r2r ?
What chipset would be used in the R2R DAC ?
I have tow questions.
Would there be a separate volume control required for the pre amp to work ? If yes, what the impedance should be.
You are saying that pre amp would fit the DAC, meaning AK DAC right ?
On the other hand it has an r2r dac, would there bea n option to choose and external DAC or the internal r2r ?
What chipset would be used in the R2R DAC ?
I may have made some misleading here.
The Preamp has build in volume control. It is based on an R2R DAC. The R2R attenuator is based on the DAC8812 from TI using discrete opamps.
It is in the same manner as for example Mark Levison has done it.
The Preamp board can be used with the frontpanel only and with the AK4490 USB DAC where the frontpanel can select 1 of 4 different digital filters.
I hope it clarifies some points here.
Thanks for the prompt response.
I see many folks here use exotic Power supply for the DAC but you recommended XP ECL30UT03 Power supply. I read that there is a lot of regulation in the board design, and as a designer yourself, do you see the need for exotics or I should keep it simple for now using simple PSU such as ECL30TU03.
How do I connect pi2 to this DAC?
Thanks again
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