Hi,
thanks for the suggestions.
Julf wrote:
I have 2 motivations for my integrated I2S streamer:
1. Get an additional digital input
I need the coax and optical in for other devices
2. Get a directly I2S integration with high quality
I thought
Pi-I2S out -> Najda I2S in -> Najda ASRC
is to be preferred against my other Pi/Hifiberry Digi based solution which is
PI-I2S out -> Hifiberry Digi I2S in -> SPDIF encoding -> SPDIF transformer/optocoupler -> SPDIF cable -> SPDIF receiver -> SPDIF decoding -> Najda ASRC
but obviously simpler does not automatically result in better. The Pi/Hifiberry Digi measures with less jitter.
By the way: The Hifiberry Digi has two SPDIF outputs: optical with of course isolation but also coax with a transformer, so also isolating. So you desribe somehow this Pi/Hifiberry Digi variant.
chaparK wrote:
Immediately after the Firmware update I disabled bass/treble and adjusted the analog output to the previous value. You can see in the measurement diagrams that the 12kHz peaks have the same level. So at least these two possible effects I can rule out.
chaparK wrote:
chaparK wrote:
It would be great, if you could adjust the FIFO length of the ASRC.
palmito wrote:
I powered the direct I2S connected Raspeberry PI with
a) the Najda 5V supply
b) a cheap smart phone switcher
c) a low ripple lab linear power supply
There was no change in the jitter measurements between a), b) and c).
For the Raspberry/Hifiberry Digi I tried both: coax and optical. No difference in measurement between them.
palmito wrote:
Nick: Is there a possibility to roll back to a previous Firmware version? Then I could make again a check if I can reproduce the previous measurements.
Cheers
Uwe
thanks for the suggestions.
Julf wrote:
I have 2 motivations for my integrated I2S streamer:
1. Get an additional digital input
I need the coax and optical in for other devices
2. Get a directly I2S integration with high quality
I thought
Pi-I2S out -> Najda I2S in -> Najda ASRC
is to be preferred against my other Pi/Hifiberry Digi based solution which is
PI-I2S out -> Hifiberry Digi I2S in -> SPDIF encoding -> SPDIF transformer/optocoupler -> SPDIF cable -> SPDIF receiver -> SPDIF decoding -> Najda ASRC
but obviously simpler does not automatically result in better. The Pi/Hifiberry Digi measures with less jitter.
By the way: The Hifiberry Digi has two SPDIF outputs: optical with of course isolation but also coax with a transformer, so also isolating. So you desribe somehow this Pi/Hifiberry Digi variant.
chaparK wrote:
Immediately after the Firmware update I disabled bass/treble and adjusted the analog output to the previous value. You can see in the measurement diagrams that the 12kHz peaks have the same level. So at least these two possible effects I can rule out.
chaparK wrote:
I measured with USB connected and pulled off: no change
chaparK wrote:
I tried and twisted the ground and signal cables closely. This made a slight improvement. Thanks for the suggestion. But still the Pi/Hifiberry Digi solution measures better than the direct I2S.
It would be great, if you could adjust the FIFO length of the ASRC.
palmito wrote:
I powered the direct I2S connected Raspeberry PI with
a) the Najda 5V supply
b) a cheap smart phone switcher
c) a low ripple lab linear power supply
There was no change in the jitter measurements between a), b) and c).
For the Raspberry/Hifiberry Digi I tried both: coax and optical. No difference in measurement between them.
palmito wrote:
Thanks, I will check the links.
Nick: Is there a possibility to roll back to a previous Firmware version? Then I could make again a check if I can reproduce the previous measurements.
Cheers
Uwe
Uwe,
Just wanted to say "well done" for actually measuring the alternatives instead of just taking something like this on faith.
Hi Ulf! Very simple! First I used FrontDesigner software FrontDesigner After designing front panel, I printed it on on self-adhesive laser film. To protect lettering, I painted it with clearcoat. If you need, I can send my file for FrontDesigner Regards, Mike
Although I understand your aim, I'm not too crazy about letting you or anyone downgrade the firmware, you had probably guessed it
I'm the one who writes the code and makes the release. I certify the only difference between V.1.2 and V.1.3 is the procedure writing to the display. It cannot impact audio and this part of code is not even accessed if the display is not being refreshed.
As you have noticed an improvement by tightening the ground and signal wires together, I'd suggest you try now to make the lines shorter, possibly with shielded cable. An isolator would also be worth trying, as you were indeed right when you noticed that SPDIF actually isolates the 2 devices.
Hi Nick,
I guess your priority is to complete the analog expansion and control boards.
And that is also a priority for me
Can they be already ordered?
Back to cabling:
My I2S cables are already quite short (abput 8cm). I twisted them, so I need the length. I will try with some shielded cable. I have some 3 wire shielded analog mic cable lying around. But probably I won't have the time before weekend.
Would the following make sense?
Using two short pieces of the mic cable:
PI ------------------------------------- Najda
first cable:
wire 1: pin 3 PCM_CLK=BCK_______________pin 23 I2S_CKR
wire 2: pin 4 PCM_FS=LRCK_______________pin 25 I2S_FSR
wire 3: pin 7 GND_______________________pin 24 and pin 26 for DGND (Y cable)
shield to housing
second cable:
wire 1: pin 6 PCM_DOUT=DATA____________pin 1 I2S_Line1
wire 2: unused
wire 3: pin 8 GND_______________________pin 2 for DGND
shield to housing
Regards,
Uwe
I guess your priority is to complete the analog expansion and control boards.
And that is also a priority for me
Can they be already ordered?
Back to cabling:
My I2S cables are already quite short (abput 8cm). I twisted them, so I need the length. I will try with some shielded cable. I have some 3 wire shielded analog mic cable lying around. But probably I won't have the time before weekend.
Would the following make sense?
Using two short pieces of the mic cable:
PI ------------------------------------- Najda
first cable:
wire 1: pin 3 PCM_CLK=BCK_______________pin 23 I2S_CKR
wire 2: pin 4 PCM_FS=LRCK_______________pin 25 I2S_FSR
wire 3: pin 7 GND_______________________pin 24 and pin 26 for DGND (Y cable)
shield to housing
second cable:
wire 1: pin 6 PCM_DOUT=DATA____________pin 1 I2S_Line1
wire 2: unused
wire 3: pin 8 GND_______________________pin 2 for DGND
shield to housing
Regards,
Uwe
Uwe,
Another alternative you could try is Cat5 data cable if you have some spare, the cable is very thin and the pairs are twisted tightly together, because the wire is solid it is easy to put in place. After all it is designed to carry data. You could use two pairs for your connections.
BTW 10cm is considered maximum for good I2S transmission, so 8cm is not that short in this context.
Hope this helps
Duncan
Another alternative you could try is Cat5 data cable if you have some spare, the cable is very thin and the pairs are twisted tightly together, because the wire is solid it is easy to put in place. After all it is designed to carry data. You could use two pairs for your connections.
BTW 10cm is considered maximum for good I2S transmission, so 8cm is not that short in this context.
Hope this helps
Duncan
Hi,
I'd like to get some advice concerning the "best" way to feed audio stream into Najda.
I'd like to play audio flac files and Deezer mp3 via Najda and a mini PC with Volumio.
First solution is to use a mini PC with a SPDIF out,the second is to use I2S out.
Both are available for Rpi, SPDIF with an extension card.
One advantage could be the cable lengt for the SPDIF if i use it.
Can we ear the diffrence with the two kind of inputs ?
I'd like to get some advice concerning the "best" way to feed audio stream into Najda.
I'd like to play audio flac files and Deezer mp3 via Najda and a mini PC with Volumio.
First solution is to use a mini PC with a SPDIF out,the second is to use I2S out.
Both are available for Rpi, SPDIF with an extension card.
One advantage could be the cable lengt for the SPDIF if i use it.
Can we ear the diffrence with the two kind of inputs ?
There's a difference, but I doubt it will be audible. Technically I2S is preferred as long as you keep your wires short and clean with proper grounding (to keep jitter to a minimum). If you need wires longer than ~10-15cm (and especially if you don't plan to mount your RPi in the same enclosure as your Najda) you might be better off using usb-spdif or some other GPIO based spdif out.
Well it's been well over a year since I first got and tried Najda and then built it into a proper case use and it's been absolutely excellent.
These days I am playing much more computer based audio having ripped all of my CD's and a few records that you can't easily buy or get on CD at all... I am using a lowly UCA-202 usb to SPDIF and that limits the resolution. I have some fairly high res files too now. No optical out on my laptop.
So thoughts are turning to I2S. I've had a trawl back a bit on this thread but I am still no really wise as to what I need.
I want something cheap that sounds good and is mounted in the Najda box (important to keep the wires to the I2S input short I understand.
This is tempting but would it be any good?
http://www.ebay.co.uk/itm/New-USB-TO...item2c87539e71
I read here way back of Tenor or Amanero based and has tested.
Amanero Technologies
http://www.ebay.co.uk/itm/LJM-Audio-...item19dde66b0c
Or are there others with better bang for buck?
I find the pin out and in designations in the specs and how they relate to Najda a bit baffling - Is it a case of having the thing in my hand and all will be obvious to an electronics numpty?
These days I am playing much more computer based audio having ripped all of my CD's and a few records that you can't easily buy or get on CD at all... I am using a lowly UCA-202 usb to SPDIF and that limits the resolution. I have some fairly high res files too now. No optical out on my laptop.
So thoughts are turning to I2S. I've had a trawl back a bit on this thread but I am still no really wise as to what I need.
I want something cheap that sounds good and is mounted in the Najda box (important to keep the wires to the I2S input short I understand.
This is tempting but would it be any good?
http://www.ebay.co.uk/itm/New-USB-TO...item2c87539e71
I read here way back of Tenor or Amanero based and has tested.
Amanero Technologies
http://www.ebay.co.uk/itm/LJM-Audio-...item19dde66b0c
Or are there others with better bang for buck?
I find the pin out and in designations in the specs and how they relate to Najda a bit baffling - Is it a case of having the thing in my hand and all will be obvious to an electronics numpty?
Hi speedysteve7,
I'm in the same process, thinking to buy a waveIO USB to I2S card :
Luckit | Audiophile grade DIY products
Maybe this link could interrest you :
ES9018 USB DAC - Hi-Resolution System*
I'm in the same process, thinking to buy a waveIO USB to I2S card :
Luckit | Audiophile grade DIY products
Maybe this link could interrest you :
ES9018 USB DAC - Hi-Resolution System*
Was told by a couple of digital 'techs' that this one was the one go to for:
Xmos DSD 384 kHz 32bit Multi Format USB to I2S SPDIF | eBay
Xmos DSD 384 kHz 32bit Multi Format USB to I2S SPDIF | eBay
Hi Pascal and Steve
That's the WaveIO board I am using, USB in and I2S out, built in the same case as the Najda. Outstanding sound, excellent support from Lucian if needed, and a diyaudio thread
BR
Jean-Louis
BR
Hi Nick!
I checked all connections and all is fine. Also I checked capacitor with my LCR-meter. The capacitance is the same as the others. No idea what to check more.
Mike
I'd suggest you make 3 cables, one for each signal. I know it's a bit of a pain because there are only 2 ground pins on the rPi header but you can probably manage something.
The next step would be a bus isolator. One of those chips would do the job nicely: ADUM1310BWRZ or IL715 if you intend to play 192 kHz sample rate files on the rPi.
Don't worry about capacitors, they're here only for debouncing the push.
Well that leaves only one thing: the pin of the micro.
Please inspect visually pin 36 of the STM8S207, the Mute button is tied to that pin. See if there's a short with the surrounding pins or a bad contact to the pad on the PCB.
You can also do a continuity test to that pin: it must be pulled to GND when you press the Mute button (do that after you have switched the unit off and pulled off the power chord).
I have got something strange going on with my Nadja...
Connecting up my phonostage via the analogue in i get the AD clipping and the bass and treble clipping lights coming on. When i attenuate the input signal (max 24db) i still get the same clipping, even though the output from the Nadja is just audible (via the speakers).
Now for the strange bit, if i remove the 10:1 SUT from the circuit, then the problem with clipping goes away. I need to add 18db of gain to the input to get it to AD clip, which knowing the cartridge sensitivity and the phonostage gain is ~ 1v, which makes sense.
Anyone got any ideas of whats wrong, as its obviously not a gain problem. My throughts are that it must be a ringing issue, but clipping at both extremes doesn't seem to support this.
( I have been using my phonostage SUT combination with my Ortofon K's for many years without issue)
Connecting up my phonostage via the analogue in i get the AD clipping and the bass and treble clipping lights coming on. When i attenuate the input signal (max 24db) i still get the same clipping, even though the output from the Nadja is just audible (via the speakers).
Now for the strange bit, if i remove the 10:1 SUT from the circuit, then the problem with clipping goes away. I need to add 18db of gain to the input to get it to AD clip, which knowing the cartridge sensitivity and the phonostage gain is ~ 1v, which makes sense.
Anyone got any ideas of whats wrong, as its obviously not a gain problem. My throughts are that it must be a ringing issue, but clipping at both extremes doesn't seem to support this.
( I have been using my phonostage SUT combination with my Ortofon K's for many years without issue)
Is it the first time you are using it?
I had this and I think others / many have.
If it is, with Najda connected disable the bass/treble setting in the appropriate front screen. I can't remember exactly where and can't connect just now...
It's in the manual and has a keyboard shortcut of Alt T. If you are to use bass and treble adjusting the headroom dB setting should do it.
If you have had Najda working fine and this suddenly happened then I don't know.
I had this and I think others / many have.
If it is, with Najda connected disable the bass/treble setting in the appropriate front screen. I can't remember exactly where and can't connect just now...
It's in the manual and has a keyboard shortcut of Alt T. If you are to use bass and treble adjusting the headroom dB setting should do it.
If you have had Najda working fine and this suddenly happened then I don't know.
Last edited:
It the first time i have tried the T/T since using the Nadja.
I don't have any bass or treble settings set all at 0db, so am not sure if that will help.
I am going to introduce some 8 order pre-fillters on the input cutting off at 20hz (rumble filter) and another to cut off everything above 40Khz to see if thats the issue. (Approach not logical though, as SUT's decay at the extremes of frequency .)
I don't have any bass or treble settings set all at 0db, so am not sure if that will help.
I am going to introduce some 8 order pre-fillters on the input cutting off at 20hz (rumble filter) and another to cut off everything above 40Khz to see if thats the issue. (Approach not logical though, as SUT's decay at the extremes of frequency .)
