Try to improve R-2R Holo Spring3 sound quality by HdmiPiPro and FifoPiQ7 (1)
I’m interested in the sound of a NOS R-2R DAC, so I bought a Holo Spring 3 last month. After three weeks break in, I have to say I like the sound more and more.
The output voltages of Spring 3 are RMS 2.9V/RCA and 5.8V/XLR, so the sound levels are a bit higher than standard DAC output levels which are RMS 2V/4V.
Spring 3 is a typical NOS R-2R but with higher accuracy than many others because of the compensation technology.
The sound is very impressive but the style is different from the popular Delta-Sigma DAC, with great transparency, higher density, more details and dynamic, more natural. The 3D image is very solid. The sound is also very clean because of the black background. Those are typical R-2R DAC sound signatures. Spring 3 could be the best R-2R DAC at this price range.
However, when comparing with my well running-in FifoPiQ7/9038Q2M Dual Mono/OPA861I/V DAC system (With 90/98MHz OCXO), What I’m not happy with is that the 3D instrument image of the Spring 3 was pretty big so the whole soundstage was not that pin-point focused and delicate. I will also feel a bit tired after listening to it for a longtime.
Spring 3 uses an internal PLL as the audio MCLK, I believe that could be the reason. Fortunately, Spring 3 has an I2S/DSD over HDMI input option, so I’m wondering if I still have a chance to improve the sound quality of my Spring 3 by feeding better external I2S/DSD signals with higher grade clock to it.
I’m gonna try my new flagship FifoPiQ7 + HdmiPiPro + MonitorPi + PurePi ultra-low jitter network streamer transport solution with my Spring 3.
Somebody said that the R-2R DACs are immune to clock jitter, but it could be not true.
https://github.com/iancanada/DocumentDownload/blob/master/HDMIpi/HdmiPiPro/HdmiPiProManual.pdf
https://github.com/iancanada/DocumentDownload/blob/master/FifoPi/FifoPiQ7/FifoPiQ7Manual.pdf
https://github.com/iancanada/DocumentDownload/blob/master/MonitorPi/MonitorPi.pdf
Spring3HdmiPiPro by Ian, on Flickr
I’m interested in the sound of a NOS R-2R DAC, so I bought a Holo Spring 3 last month. After three weeks break in, I have to say I like the sound more and more.
The output voltages of Spring 3 are RMS 2.9V/RCA and 5.8V/XLR, so the sound levels are a bit higher than standard DAC output levels which are RMS 2V/4V.
Spring 3 is a typical NOS R-2R but with higher accuracy than many others because of the compensation technology.
The sound is very impressive but the style is different from the popular Delta-Sigma DAC, with great transparency, higher density, more details and dynamic, more natural. The 3D image is very solid. The sound is also very clean because of the black background. Those are typical R-2R DAC sound signatures. Spring 3 could be the best R-2R DAC at this price range.
However, when comparing with my well running-in FifoPiQ7/9038Q2M Dual Mono/OPA861I/V DAC system (With 90/98MHz OCXO), What I’m not happy with is that the 3D instrument image of the Spring 3 was pretty big so the whole soundstage was not that pin-point focused and delicate. I will also feel a bit tired after listening to it for a longtime.
Spring 3 uses an internal PLL as the audio MCLK, I believe that could be the reason. Fortunately, Spring 3 has an I2S/DSD over HDMI input option, so I’m wondering if I still have a chance to improve the sound quality of my Spring 3 by feeding better external I2S/DSD signals with higher grade clock to it.
I’m gonna try my new flagship FifoPiQ7 + HdmiPiPro + MonitorPi + PurePi ultra-low jitter network streamer transport solution with my Spring 3.
Somebody said that the R-2R DACs are immune to clock jitter, but it could be not true.
https://github.com/iancanada/DocumentDownload/blob/master/HDMIpi/HdmiPiPro/HdmiPiProManual.pdf
https://github.com/iancanada/DocumentDownload/blob/master/FifoPi/FifoPiQ7/FifoPiQ7Manual.pdf
https://github.com/iancanada/DocumentDownload/blob/master/MonitorPi/MonitorPi.pdf
Spring3HdmiPiPro by Ian, on Flickr
Last edited:
Hello Ian,
Pls could you give me some advice.
I build a Raspberry stack with StationPro, ReceiverPi, Fifo Q7 and some additional boards. I can see the system in Roon and play music. However there is now output/input on de Fifo as you can see on the MonitorPi and ESS controller.
The previous setup with Raspberry and MonoDAC worked fine.
Any idea what could cause the problem?
Thank you!!
rgrds Jan
Pls could you give me some advice.
I build a Raspberry stack with StationPro, ReceiverPi, Fifo Q7 and some additional boards. I can see the system in Roon and play music. However there is now output/input on de Fifo as you can see on the MonitorPi and ESS controller.
The previous setup with Raspberry and MonoDAC worked fine.
Any idea what could cause the problem?
Thank you!!
rgrds Jan
R2R dacs are not immune to clock jitter. With my TDA1541A dac and the R2R dac from Andrea the advantage of a low jitter clock is clearly audible.
R2R dacs sound more natural and analog than delta/sigma dacs.
I hope you can improve the Holo R2R dac and experience the magic of R2R.
regards,
R2R dacs sound more natural and analog than delta/sigma dacs.
I hope you can improve the Holo R2R dac and experience the magic of R2R.
regards,
From the pictures, MonitorPi shows that FifoPiQ7 got wrong XO frequencies. Please read the user's manual troubleshoot section for the solution
https://github.com/iancanada/DocumentDownload/blob/master/FifoPi/FifoPiQ7/FifoPiQ7Manual.pdf
Ian
Hello Ian,
I am building a streamer + DAC and will be using the StationPi Pro + ReceiverPi Pro + Fifopi Q7 + etc… I’d like to implement a selector switch to control the input selection through the StatioPi Pro controller but am not keen to use a screen (like the 4D System GEN4-ULCD-24PT as described in the documentation).
I have a 10-pin selector 5V logic board for a rotary switch (6 selection pins, 2x GND and 2x +5V input). When an output position is selected, it becomes logic high. Is it possible such a selector with the StationPi Pro? If so, could you please help with telling which pins of the J8 connector needs to be linked to the 10-pin selector board for Rpi, RCA, OPT, HDMI and USB (amanero)?
Thanks in advance!
I am building a streamer + DAC and will be using the StationPi Pro + ReceiverPi Pro + Fifopi Q7 + etc… I’d like to implement a selector switch to control the input selection through the StatioPi Pro controller but am not keen to use a screen (like the 4D System GEN4-ULCD-24PT as described in the documentation).
I have a 10-pin selector 5V logic board for a rotary switch (6 selection pins, 2x GND and 2x +5V input). When an output position is selected, it becomes logic high. Is it possible such a selector with the StationPi Pro? If so, could you please help with telling which pins of the J8 connector needs to be linked to the 10-pin selector board for Rpi, RCA, OPT, HDMI and USB (amanero)?
Thanks in advance!
Ian, I’m picking this up again after a while and wanted to confirm a few points:
- Even if using FIFOPI Q3 without a Rasberry Pi, both J3 5V and J2 3.3V on FIFOPI need to be powered? If so, what does J3 5V power?
- When using BridgePi, is there any benefit to providing it separate power at its own J5 power header or fine to omit?
- When using BridgePi, FIFOPI Q3, ReclockerPi + connecting mclk to my Buffalo DAC - should I be using the mclck output of the BridgePi at all or omit? I have mclck running from FIFOPI to receiver pi and then connect mclck and the other u.fl outputs from receiver pi to my DAC.
Thank you.
@stew1234
- Even if using FIFOPI Q3 without a Rasberry Pi, both J3 5V and J2 3.3V on FIFOPI need to be powered? If so, what does J3 5V power?
- Yes, you will need both 5V for dirty side and 3.3V for clean side.
- When using BridgePi, is there any benefit to providing it separate power at its own J5 power header or fine to omit?
- No, no need additional power for BridgePi.
- When using BridgePi, FIFOPI Q3, ReclockerPi + connecting mclk to my Buffalo DAC - should I be using the mclck output of the BridgePi at all or omit? I have mclck running from FIFOPI to receiver pi and then connect mclck and the other u.fl outputs from receiver pi to my DAC.
- No, no need connect MCLK from BridgePi
I second this. I am a big fan of R2R DACs. Their sound is completely dependent on all the usual stuff. Clock, power supplies and output stage. Alone with using your source with a very good clock, I'd guess the DAC would do well with your super cap conditioners on all the power supplies. Reviews suggest the output stage is pretty good as supplied. Could always experiment with triodes as an alternative.
Thank you. As a follow-up, is there any difference running the MCLK out of BridgePi vs. from FIFOPI to the dac or are the outputs identical for MCLK?
Also, I will likely need a two case build due to number of power supplies and transformers. I'm assuming most important is keeping power lines short from UcConditioners to DAC modules which can all be positioned very close. I'll be using various LT3045 power supplies and a linear pi - does the length of power line from the power supplies into the UcConditioner matter (within reason) given they will act as a buffer or still best to keep as short as possible? I'd rather not run ac secondaries from one chassis to another, so would plan to house the transformers + power supplies in one chassis and UcConditioners + DAC and various modules in another but the distance from power supplies to UcConditioner could end up being a foot or more.
Thanks again.
I would not use super caps on the analog side of a dac. They are very good for the streamer and digital side but not for analog.
This is how I have used the super caps with battery supplies, lenearpi on my streamer. the dac is fed with shunt regulators.
Agreed. I use supercaps on the digital side of the TDA1541A to good effect. I use Blackgate N in Super-E configuration plus Blackgate HiQ close to the chip on the -15V analogue. No idea what would work best with Ian's DAC. Point is the power supply impacts sound and is worth experimenting.
Hi Ian,
The Accusilicon pin 1 pull up resistor behaviour caused the problem. Bending this pin solved the problem. You described it in the Fifo-manual.
I'am very impressed by the sound quality!
thanks
@Supersurfer
Your TDA1541 DAX looks very cool! Congratulations!
Are the two mono block TDA1541 in parallel for each channel?
How do you like the sound by comparing with other R-2R DACs?
@JanHD
I'm glad the issue was fixed.
I really like the MonitorPi, it shows all the real status and makes it much easier to debug the system.
StationPi Pro has a manual control port J14, you can figure out how to use it to perform the source selection.
You can reference to the user's manual
https://github.com/iancanada/Docume.../StationPiPro/StationPiProUsersManualV1.1.pdf
As well as the schematic
https://github.com/iancanada/Docume...Adapters/StationPiPro/StationPiProSchV1.0.pdf
