It's perfectly possible that you can hear the difference but I can't, though I would doubt that it's because of the op-amp. There's also nothing wrong with preferring the SD player.
Btw, even though I still haven’t had the chance to ABX test SE and BAL outputs, is there any reasonable theory that might explain the great perceived improvements in spaciousness of sound in balanced mode/dual-mono? If not, we would need even stronger conclusions from the listening tests. Perhaps Soren has some potential justifications since the totl Soekris is dual mono?... For the moment I’d be happy to acknowledge that I don’t know whether or how dual mono might bring about audible improvements.
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This is pretty much the hall mark of balanced equipment and connections in general. Ground is no longer a signal carrying conductor, ground currents can no longer interfere with signal and this greatly improves the integrity of transfer.
Interestingly, there are also detractors who reckon the increased spaciousness detracts from the musical message.
Has someone tried two boards parallel yet?I already have two 1121 in dual mono but thinking of paralleling two more. - Besides benefits or downsides caused by complexity:
How should the connection of those look like?
- one board in master mode, the others in slave mode
- clock out from master with three buffers
- outputs just parallel
The thing is, the manual does not say that the i2s output is active when board is salve, so I can not assume that I can hook the slave boards up in series.
And one more thing: TNT (I think you use the 1121 as well) did you remove the HF filter capacitor at the output? Some recommend this mod on the 1021 but I've not heard from someone removing it on the 1121. Is it worth trying?
How should the connection of those look like?
- one board in master mode, the others in slave mode
- clock out from master with three buffers
- outputs just parallel
The thing is, the manual does not say that the i2s output is active when board is salve, so I can not assume that I can hook the slave boards up in series.
And one more thing: TNT (I think you use the 1121 as well) did you remove the HF filter capacitor at the output? Some recommend this mod on the 1021 but I've not heard from someone removing it on the 1121. Is it worth trying?
Paralleling more than 2 is certainly something you can only do with 1121 and the perfectionistic motivation is powerful. But I think the only benefit is lower noise floor and more dynamic range in the 110-120db range, which is still within what we can discern theoretically. You might also get better THD measurements but I'm not sure how much that matters in reality.
I guess it comes down to your budget, which is not easy to fully determine on a personal level. If cost is no object, maybe consider charity?
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I've been through many of the posts here but am a little confused about the 1021 vref mod. I have a rev 5 board. I only see 12 pairs of vias for the caps (c166-c177).
1. Where are the other 4 caps and vias?
2. I read that more capacitance is generally better, is this a decent cap to use? APSG160ELL222MJ20S United Chemi-Con | Mouser
3. Also, is lowering the output resistor value and shorting the feedback cap recommended with the rev 5 board?
Thanks for any help.
1. Where are the other 4 caps and vias?
2. I read that more capacitance is generally better, is this a decent cap to use? APSG160ELL222MJ20S United Chemi-Con | Mouser
3. Also, is lowering the output resistor value and shorting the feedback cap recommended with the rev 5 board?
Thanks for any help.
Maybe you can open up the vias around the shift registers and hang 16 caps there, but in rev4/5 you can easily add 12 caps through the open vias. I believe that's the best place to add caps considering risk/benefit/time cost.
Your choice of caps is excellent. I didn't realize UCC make 2200uF 16v polymers, but apparently they do..
Depending on whose recommendation you're getting. I recommend you learn why one might claim either way. Otherwise you'll find the process unnecessarily confusing. If you reject learning, DIY might not be a really good choice in many cases. If you ask me, leave the caps alone and use the buffer if you need.
OK! Whats the magnitude of the problem? What levels can arise and of how long?
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Depends entirely on the audio source. Worst case would be full level DC - can happen through some glitch in the digital domain. It might wreck your speakers instantly.
On the other hand, if your power amp is AC coupled I see no need for the filter. The DAC sounds much better without it to my ears.
In my studio gear I have long experimented with DC and AC coupling and concluded that, if done correctly, AC coupling works very well. Just use large enough electrolytic coupling caps.
BTW, the music you buy and listen to usually travelled through dozens of standard cheap electrolytic caps already.
This is the output and you can see the wiring scheme. What would be the best way to connect this directly to Soekris board i2s input?
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I found this cable but first it's way way too expensive and secondly I need one end to contact directly to the appropriate pins in the Soekris board
I meant to peace this link there: FS - Supra HDMI Cable (0.5m) I2S | Headphone Reviews and Discussion - Head-Fi.org
Sorry