The transporter will introduce jitter. Isolation before re-clock, is the place to isolate and I wouldn't be using the TP (or a pair of them) to do it. The primary purpose of TP is LVDS, making it OK for the I2S signals to travel a metre rather than a few cm's. Any isolation provided is secondary.
Hi Clive,
I had not clocked (pardon the pun) how much jitter a Transporter pair would introduce. Russ posts information here:
http://www.diyaudio.com/forums/twisted-pear/201106-introducing-bit-teleporter.html#post2793811
So I hear what you say.
Simon, how I read what you plan to do is that you intended to use the Transporter between the Pi and the Kali. Agreed, the LVDS transformation (to and back) with add jitter, BUT any isolators will too. Either should have minimal effect on the output due to the Kali.
Because the LVDS is a non-ground-referenced signal, it does break the ground connection, but is not 'galvanically isolated' as most isolators are.
Because it would be used before the Kali, I suspect it is a useful and valid option in this setup, especially before there are isolation options available.
Still, the BEST option from a lowest noise and jitter perspective would be to add 3 channels (BCLK, WCLK, DATA) I2S-signal-only (plus whatever channels are needed for control) isolators on the Kali board just after the FPGA and before the reclocking flipflops and the clocks, similar to how Ian's full FIFO setup is configured. Then it would output the 3 I2S channels on the expansion header, along with passing through the other data channels. ***(SEE BELOW)***
On the Kali 2.0, this could be setup with a jumper where the output side is powered from the regulators on the Kali if the jumper is present.. and one would have to provide another power feed if it is not. Do this, but don't put any regulation on the post-isolator side to simplify the setup... anyone who will be setting up the fully isolated version would be able to supply the required 3.3v there.
If you add this configuration PLUS a 3.3v regulator on the Kali to feed the expansion header 3.3v pins, that Kali 2.0 PLUS the TBDefined isolator HAT would provide several options that would trade off the greatest flexibility and highest fidelity. Some include:
1. It could be used alone with 1-2 power supplies (either one for the entire setup or one for the Pi and another for the Kali and DAC), but by adding the 3.3v on the expansion header it would be much more universal than the current one.
2. It could be used alone with 3-4 (or more) power supplies (R-Pi, Kali input, Kali output+DAC HAT or even a DAC HAT or otherwise separate DAC powered separately) for the ultimate in fidelity with this setup for a minimalistic user.
3. It could be used with the TBD isolation HAT for better fidelity (lower noise and jitter) than #1, but not quite as good as #2. This option would likely require a minimum of 2 power supplies, but we'll know more as the design and configuration of the isolation HAT emerges.
Something like this PLUS adding 'DAC as Master' capability as you mentioned before would be very cool!
My latest 2 cents.
Greg in Mississippi
*** Where will one be able to access the MCLK from the Kali? On one of the expansion header pins or elsewhere?
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cdsgames, Clive, Greg,
Have to say, I'm a bit blown away…
In a nutshell, seamless harmonics, subtle pitch, tone, vol changes, speed, flavor type *details*, to the extreme. Detail as in “highs” is too simplistic to describe this. Incredibly quick bass.
I plan to flesh this out a little/tone it down a little, go back to my main Dac, a PSAudio, and new Schiit multibit R2R Dac— The PSAudio is very sensitive to SPDIF quality, also have the new digi+ PRO to try on it.
If you’d like to slog through my brain dump notes, this a bit of audiophile speak I'm uncomfortable with but gotta try to describe what's here!
***Just felt I need to get this out for you guys***! More later
Thanks!!
Imaging, panning effects too the millimeter left to right, front back— space between speakers maxed out, no gaps, outside speakers — it’s a bit odd, that really stuck out.
…making a list of specific tracks
Lorde, Still Sane, listen to her voice pannng, now more precise — also cavernous bass
Deepest bass, amazing subtle tone variation, fast, keeps up w/mids
Female vocals, go beautifully high & wispy
Bebel Gilberto (Inspiracao) 24/96 — stunning, impact, beautiful digital effects, again… panning, cavernous bass, yet details at ease
notes get in, get out, instantly, but sustain… voice on this track more spacious
Immense soundstage, wide, deep, 3d, different shapes album to album, track to track (sure it is anyway, but this is more).
Glass Animals (Hazy 2:16 in - beautiful, Jdnt - fun) -- phasy things come forward
Transients, sooo varied on the same track, not flat, and you can hear though them…
guitars exciting sounding, vibration
newer smashing pumpkins sound amazing, the completeness of sustained tones so interesting
a perfect circle, the noose, 3:06, the bass guitar, wow
fluctuations, more extreme
paul simon, start of song, stranger to stranger
I can get into the volume easily, just sounds good — and yet also seems dynamic at the lowest volume (good for late night)
Think thats a character of the PCM5xxx chip, it’s relentlessly flat & polite, hazy… complete at low volume *BUT*… not like this (add dynamics, clarity, still at low vol.)
Have to say, I'm a bit blown away…
In a nutshell, seamless harmonics, subtle pitch, tone, vol changes, speed, flavor type *details*, to the extreme. Detail as in “highs” is too simplistic to describe this. Incredibly quick bass.
I plan to flesh this out a little/tone it down a little, go back to my main Dac, a PSAudio, and new Schiit multibit R2R Dac— The PSAudio is very sensitive to SPDIF quality, also have the new digi+ PRO to try on it.
If you’d like to slog through my brain dump notes, this a bit of audiophile speak I'm uncomfortable with but gotta try to describe what's here!
***Just felt I need to get this out for you guys***! More later
Thanks!!
Imaging, panning effects too the millimeter left to right, front back— space between speakers maxed out, no gaps, outside speakers — it’s a bit odd, that really stuck out.
…making a list of specific tracks
Lorde, Still Sane, listen to her voice pannng, now more precise — also cavernous bass
Deepest bass, amazing subtle tone variation, fast, keeps up w/mids
Female vocals, go beautifully high & wispy
Bebel Gilberto (Inspiracao) 24/96 — stunning, impact, beautiful digital effects, again… panning, cavernous bass, yet details at ease
notes get in, get out, instantly, but sustain… voice on this track more spacious
Immense soundstage, wide, deep, 3d, different shapes album to album, track to track (sure it is anyway, but this is more).
Glass Animals (Hazy 2:16 in - beautiful, Jdnt - fun) -- phasy things come forward
Transients, sooo varied on the same track, not flat, and you can hear though them…
guitars exciting sounding, vibration
newer smashing pumpkins sound amazing, the completeness of sustained tones so interesting
a perfect circle, the noose, 3:06, the bass guitar, wow
fluctuations, more extreme
paul simon, start of song, stranger to stranger
I can get into the volume easily, just sounds good — and yet also seems dynamic at the lowest volume (good for late night)
Think thats a character of the PCM5xxx chip, it’s relentlessly flat & polite, hazy… complete at low volume *BUT*… not like this (add dynamics, clarity, still at low vol.)
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I stand by my 1st impression thick, focused details top to bottom... through headphones I was also thinking flat, too polite, like the hifiberry-- but have more time on it now, and very different story on speakers!
I'll try the AMP 2.1 this week--
If you liked Piano 2.1 (working as a 2.0) ...just wait to see the 2.1 working as a 2.1
Hi ,
Isolator (before Kali) will have 0 effect on output of Kali
Regarding the isolator placement...I get what you are saying in option 2..but the FPGA (with few gates) is generally speaking less noisy than an arm cpu.
Anyway this week we will check for noise (fpga) on oscilloscope and make a final decision on i2s isolator placement. Its clear that rest of signals will be isolated before Kali.
3.3v we are looking into adding this, using LDO but mA will be severely limited (200mA max)
Master DAC :
We think its the ultimate setup...a master DAC and a FIFO buffer become the ultimate RTOS. OS itself has an influence on sound. I know a lot of audio aps (for RPI) are looking into using RTOS to achieve ultimate audio fidelity...with Kali the RTOS is already there (a few cm from DAC ic) holding s steady 0.x seconds of audio sample. Clocks are a few mm from DAC IC. Fpga is a real time OS so DATA will be on time every time. Architecture wise , its bulletproof.
Isolator (before Kali) will have 0 effect on output of Kali
Regarding the isolator placement...I get what you are saying in option 2..but the FPGA (with few gates) is generally speaking less noisy than an arm cpu.
Anyway this week we will check for noise (fpga) on oscilloscope and make a final decision on i2s isolator placement. Its clear that rest of signals will be isolated before Kali.
3.3v we are looking into adding this, using LDO but mA will be severely limited (200mA max)
Master DAC :
We think its the ultimate setup...a master DAC and a FIFO buffer become the ultimate RTOS. OS itself has an influence on sound. I know a lot of audio aps (for RPI) are looking into using RTOS to achieve ultimate audio fidelity...with Kali the RTOS is already there (a few cm from DAC ic) holding s steady 0.x seconds of audio sample. Clocks are a few mm from DAC IC. Fpga is a real time OS so DATA will be on time every time. Architecture wise , its bulletproof.
Thank you ScKramer for your comments on these boards. I'm very interested in the kali and piano dac hat for the pi. Subscribed as of post #1, on both threads. I hoped and thought that this combination should sound good. Also to have the dsp done in the dac itself is a very good thing, I think. Have experienced bi-amping with 20-100Hz to one amp/woofers and the rest to my monitors/amp. This really made a jump in SQ! Keep up the good work cdsgames and team! Much appreciated!
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new review of Kali and Piano 2.1
A old school reviewer, he prefers vinyl .
Allo Audio Piano DAC for Raspberry Pi - Page 2
My favorite part
"
A old school reviewer, he prefers vinyl .
Allo Audio Piano DAC for Raspberry Pi - Page 2
My favorite part
"
All this was just the DAC. Fitting the Kali brings about further noticeable improvements. I would say you get an extra 10% on top, so it's not night and day but it's wringing the last ounces of performance out of the system"
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I think that a lot of people will be surprised on the improvement that a 2.1 system can make , with the xover on the digital domain
Like I said , we are using a 4 pole xover....
In my opinion its more important (for the sound quality) to use a 2.1 system than anything else.
Just my opinion.
Like I said , we are using a 4 pole xover....
In my opinion its more important (for the sound quality) to use a 2.1 system than anything else.
Just my opinion.
I'm still waiting for SC to chime in on my pig comment after he spent time and money finding that you cannot turn a pig into a prize winning racehorse.
I've not tried the Piano on it's own, and really do not want to... it's slave mode (no on board clocks) into the messy pi i2s-- it'll suffer from that, correct? Don't think a fair assessment could be made.I'm excited by something here
most certainly the Kali!
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Scott,
Thanks for your report. I'm doubly excited now... and even more curious to hear how close the Kali comes to the Ian Reclocker setup.
Just waiting now... and I saw the package with a Kali go the wrong direction (north instead of south), checked, and saw I made a mistake when I gave my zip code. Hopefully the USPS untangles that soon.
In the meantime, based on what I heard comparing my modified HFBD+P to the largely stock Mamboberry and to my highly modified Panasonic S47 DVD player this weekend... and on what Soundcheck reported on his Mamboberry LS.... and the reports here and elsewhere on the Kali, I'm contemplating some mods to my Mamboberry to help maximize its performance on the Kali.
More later on that in Soundcheck's MB LS thread.
Greg in Mississippi
Thanks for your report. I'm doubly excited now... and even more curious to hear how close the Kali comes to the Ian Reclocker setup.
Just waiting now... and I saw the package with a Kali go the wrong direction (north instead of south), checked, and saw I made a mistake when I gave my zip code. Hopefully the USPS untangles that soon.
In the meantime, based on what I heard comparing my modified HFBD+P to the largely stock Mamboberry and to my highly modified Panasonic S47 DVD player this weekend... and on what Soundcheck reported on his Mamboberry LS.... and the reports here and elsewhere on the Kali, I'm contemplating some mods to my Mamboberry to help maximize its performance on the Kali.
More later on that in Soundcheck's MB LS thread.
Greg in Mississippi
Wow Very cool Scott!cdsgames, Clive, Greg,
Have to say, I'm a bit blown away…
In a nutshell, seamless harmonics, subtle pitch, tone, vol changes, speed, flavor type *details*, to the extreme. Detail as in “highs” is too simplistic to describe this. Incredibly quick bass.
I plan to flesh this out a little/tone it down a little, go back to my main Dac, a PSAudio, and new Schiit multibit R2R Dac— The PSAudio is very sensitive to SPDIF quality, also have the new digi+ PRO to try on it.
If you’d like to slog through my brain dump notes, this a bit of audiophile speak I'm uncomfortable with but gotta try to describe what's here!
***Just felt I need to get this out for you guys***! More later
Thanks!!
Imaging, panning effects too the millimeter left to right, front back— space between speakers maxed out, no gaps, outside speakers — it’s a bit odd, that really stuck out.
…making a list of specific tracks
Lorde, Still Sane, listen to her voice pannng, now more precise — also cavernous bass
Deepest bass, amazing subtle tone variation, fast, keeps up w/mids
Female vocals, go beautifully high & wispy
Bebel Gilberto (Inspiracao) 24/96 — stunning, impact, beautiful digital effects, again… panning, cavernous bass, yet details at ease
notes get in, get out, instantly, but sustain… voice on this track more spacious
Immense soundstage, wide, deep, 3d, different shapes album to album, track to track (sure it is anyway, but this is more).
Glass Animals (Hazy 2:16 in - beautiful, Jdnt - fun) -- phasy things come forward
Transients, sooo varied on the same track, not flat, and you can hear though them…
guitars exciting sounding, vibration
newer smashing pumpkins sound amazing, the completeness of sustained tones so interesting
a perfect circle, the noose, 3:06, the bass guitar, wow
fluctuations, more extreme
paul simon, start of song, stranger to stranger
I can get into the volume easily, just sounds good — and yet also seems dynamic at the lowest volume (good for late night)
Think thats a character of the PCM5xxx chip, it’s relentlessly flat & polite, hazy… complete at low volume *BUT*… not like this (add dynamics, clarity, still at low vol.)
Pricing
Kali with 22/24Mhz Oscillators up to 24/192Khz 69$
Kali with 44/48Mhz Oscillators up to 24/382Khz 75$
Piano --27$
Piano 2.1---49$
Volt (shield) ---29$
Volt + (standalone with CM on it) 39$
CM---15$
LLC PSU (with CM on board) the perfect PSU for TPA 3116/18 59$
Pricing might still change, but this is what I got at this point...
Kali with 22/24Mhz Oscillators up to 24/192Khz 69$
Kali with 44/48Mhz Oscillators up to 24/382Khz 75$
Piano --27$
Piano 2.1---49$
Volt (shield) ---29$
Volt + (standalone with CM on it) 39$
CM---15$
LLC PSU (with CM on board) the perfect PSU for TPA 3116/18 59$
Pricing might still change, but this is what I got at this point...