The Zishan dsd's corner

[Ivan TT]

I don't know if all those are in the audio path, or if they are part of the power circuit.

For the reference:

Audio input caps: 100uF or more, 6.3V (or more), 6.3x11mm (or thereabouts) - remove DC from DACs outs (which is present there by design).

Audio output caps: 220uF or more, 10V (or more), size - not sure - remove DC from audio amp's output AKA "protection" caps protecting earphones from the damage induced by DC that could be introduced by opamps swapping or mods (e.g. one of +/- power rails disconnecting). Earphones resistance + output resistors + capacitance form a High Pass Filter, increasing capacitance MAY improve low frequency response (stock resistors + 220uF caps + 32Ohm earphones give cutoff frequency of 13Hz).

Power caps caps: I would not worry about them, actually. But if there's an itch to replace them I believe EEEFT1C221AP would be a good choice.

 

[Merlin-PT]

@ThanosD
Some "audio input caps" that are available to order in arrows and we can try:
-> To try instead of the 4x 100uf 16V you can use these:
https://www.arrow.com/en/products/ufg1a101mem/nichicon
https://www.arrow.com/en/products/eeu-fc1c101h/panasonic
I prefer the above of the available options in arrow, but If you want some more to try:
https://www.arrow.com/en/products/ufw1e101med/nichicon (these are supposely the same model as stock, but arrow didn't had lower voltage and size to deliver)
https://www.arrow.com/en/products/eeu-fm1e101/panasonic

Some "audio ouput caps" that are available to order in arrows and we can try:
-> Try instead of the 2x 220uF 10V:
https://www.arrow.com/en/products/ufw1e221mpd/nichicon (I'm not sure if this fits, I tried it with the player opened, arrow doesn't have lower voltage in stock now)
https://www.arrow.com/en/products/eeu-fm1a221/panasonic

These are just options from arrow for testing, unfortunately arrow don't sell ELNA models: cerafine, silmic, silmic II, I read everywhere they are very good and there also other brands suggested in this thread.

 

[ThanosD]

Could you post a link to the photo of Ivan circuit you want to do?

Is the last iteration here?
https://www.head-fi.org/threads/the-zishan-dsds-corner.826185/page-114#post-14768537

Or the previous iteration here?
https://www.head-fi.org/threads/the-zishan-dsds-corner.826185/page-105#post-14736631

Unfortunately I can't. He has a pseudo balanced setup, that requires a lot of soldering, mainly with hot air, and I don't have neither much experience with smd, nor a hot air station. He will walk me through some easy steps to just configure the opa1622 as an output buffer (if I understand correctly) to solve the impedance problem at the 3.5 output that can be performed with a simple soldering iron, as I will be soldering mostly jumpers, when I receive my unit. I will leave the balanced out untouched. After all I would used it for driving bigger cans, that would probably have enough impedance that there wouldn't be an issue.

EDIT: damn, you guys are fast. Give me a minute to read your posts

 

[ThanosD]

For the reference:

Audio input caps: 100uF or more, 6.3V (or more), 6.3x11mm (or thereabouts) - remove DC from DACs outs (which is present there by design).

Audio input caps: 220uF or more, 10V (or more), size - not sure - remove DC from audio amp's output AKA "protection" caps protecting earphones from the damage induced by DC that could be introduced by opamps swapping or mods (e.g. one of +/- power rails disconnecting). Earphones resistance + output resistors + capacitance form a High Pass Filter, increasing capacitance MAY improve low frequency response (stock resistors + 220uF caps + 32Ohm earphones give cutoff frequency of 13Hz).

Power caps caps: I would not worry about them, actually. But if there's an itch to replace them I believe EEEFT1C221AP would be a good choice.

Thanks a lot for the heads up. Ok, so I will be changing the power caps with the Panasonic you suggested, and the input caps with one of the suggested ones by Merlin-PT. I will order the replacements for the output caps too, even if I don't end up using them.

@ThanosD
Some "audio input caps" that are available to order in arrows and we can try:
-> To try instead of the 4x 100uf 16V you can use these:
https://www.arrow.com/en/products/ufg1a101mem/nichicon
https://www.arrow.com/en/products/eeu-fc1c101h/panasonic
I prefer the above of the available options in arrow, but If you want some more to try:
https://www.arrow.com/en/products/ufw1e101med/nichicon (these are supposely the same model as stock, but arrow didn't had lower voltage and size to deliver)
https://www.arrow.com/en/products/eeu-fm1e101/panasonic

Some "audio ouput caps" that are available to order in arrows and we can try:
-> Try instead of the 2x 220uF 10V:
https://www.arrow.com/en/products/ufw1e221mpd/nichicon (I'm not sure if this fits, I tried it with the player opened)
https://www.arrow.com/en/products/eeu-fm1a221/panasonic

These are just options from arrow for testing, unfortunately arrow don't sell ELNA models: cerafine, silmic, silmic II, I read everywhere they are very good and there also other brands suggested in this thread.

Ok, so I will order these for the output caps, as well these and these for the input caps. How is that some "similar" capacitors of the same size, have quite different voltage ratings?

Thanks a lot guys for the help.

 

[Merlin-PT]

I like both of those input caps options better than the stock ones.
Regarding the output caps, I also liked the sound of the stock ones (blue color) with some opamps.

 

[HeyManslowdown97]

I order these from a UK site for the
output caps, they are considered warm if that’s what you like. Haven’t got them yet but a few folks on the thread rec’d them! (Link below)

I also orders MUSE nichicons NZ, got them today and they are a little too big. I’m thinking of just expanding the connector on between the Ak4497 DAC and ARM and just make it bigger and exposed for now.

I ordered another Zishan since they are MUCH cheaper now because Ak4499 drops in May and everyone is gunning for that one. Me, I’ll sit it out until Zishan or some other Chinese maker makes a good DIY player

I may just use that new one as a portable player and this one as a just home devise until I figure out how the I’ll case it figured out. My only pet peeve of it being exposed at home is the wire connection to the battery (what a pain in a**).

I might just get an aluminum casing custom made or I’ll design one using a 3D printer and outsource it. I’d also like to find a spinning wheel as a dial like the iPod Classic instead of the buttons and bring back the volume knob on the top of the player if you really need those resistors?! The wheel just needs Springs on top of button, I believe to correspond with the buttons.

At some point some just needs to design a PCB board so we don’t keep pur good specs on a cheap board with fake parts! A quality board cost 3 bucks at most to scheme. I don’t have that knowledge to do it but it just makes sense. Think about guys!

https://www.hificollective.co.uk/catalog/470uf-25v-audio-note-standard-electrolytic.html

Ivan- I saw you took the Power Caps out what are they meant for and what did you replace them with aluminum can ones???

I will probably remove the top 2 (ELNA?) capacitors, like Ivan did, so I am mostly looking for replacements for the other six at the left side of the board, and the 4 near the AK4497 chip. I don't know if all those are in the audio path, or if they are part of the power circuit. But I saw in many pictures that people have changed them, and thought it might be a good idea.

 

[HeyManslowdown97]

I like both of those input caps options better than the stock ones.
Regarding the output caps, I also liked the sound of the stock ones (blue color) with some opamps.

Good point about the hot air iron from China. You’re right, I’d probably burn the house down. Lol.

It is interesting how the Chinese don’t get power supplies to the sockets. It’s like they don’t understand what a ground is used for.

I got a preamp with a power cord from China and the thing was doing all kinds of funky stuff so I ended up replacing it here! And luckily the problem was solved

 

[kookaudio]

As for the 220uf output caps I chose these
https://www.hificollective.co.uk/catalog/220uf-16v-audio-note-standard-electrolytic-capacitor.html

 

[endia]

I order these from a UK site for the
output caps, they are considered warm if that’s what you like. Haven’t got them yet but a few folks on the thread rec’d them! (Link below)

I also orders MUSE nichicons NZ, got them today and they are a little too big. I’m thinking of just expanding the connector on between the Ak4497 DAC and ARM and just make it bigger and exposed for now.

I ordered another Zishan since they are MUCH cheaper now because Ak4499 drops in May and everyone is gunning for that one. Me, I’ll sit it out until Zishan or some other Chinese maker makes a good DIY player

I may just use that new one as a portable player and this one as a just home devise until I figure out how the I’ll case it figured out. My only pet peeve of it being exposed at home is the wire connection to the battery (what a pain in a**).

I might just get an aluminum casing custom made or I’ll design one using a 3D printer and outsource it. I’d also like to find a spinning wheel as a dial like the iPod Classic instead of the buttons and bring back the volume knob on the top of the player if you really need those resistors?! The wheel just needs Springs on top of button, I believe to correspond with the buttons.

At some point some just needs to design a PCB board so we don’t keep pur good specs on a cheap board with fake parts! A quality board cost 3 bucks at most to scheme. I don’t have that knowledge to do it but it just makes sense. Think about guys!

https://www.hificollective.co.uk/catalog/470uf-25v-audio-note-standard-electrolytic.html

Ivan- I saw you took the Power Caps out what are they meant for and what did you replace them with aluminum can ones???

me too using same caps for output in my 4495 dsd. they are kinda warm but not too syrupy. more of analog timbre which is contrary to stock re3s. also they have very well resolution and imaging too .

 

[ThanosD]

I think that I don't prefer warm sound signatures. But I don't have a complete opinion yet. So, do you have any suggestions for a cap that is more, neutral, I guess? I might not use them at all, but they are pretty cheap, and they are not gonna be wasted, so I am ordering them anyways.

I’d also like to find a spinning wheel as a dial like the iPod Classic instead of the buttons and bring back the volume knob on the top of the player if you really need those resistors?! The wheel just needs Springs on top of button, I believe to correspond with the buttons.

At some point some just needs to design a PCB board so we don’t keep pur good specs on a cheap board with fake parts! A quality board cost 3 bucks at most to scheme. I don’t have that knowledge to do it but it just makes sense. Think about guys!

https://www.hificollective.co.uk/catalog/470uf-25v-audio-note-standard-electrolytic.html

I don't know about the iPod wheel, but I think I read a while ago, that it is possible to put a volume knob, but can't recall anything more specific. Maybe the other guys know.

And now, onto the pcb thing. I think that the problem is not the cost of printing such a board. Many of the upgrades that have been done here, come close, if not surpass, the cost of the actual player.
The problem is, that it is not that easy to design an actual board (that is dac-amp combo, has 2 outputs, and needs to be small) without proper knowledge. Electrical engineers take whole classes regarding pcb designing and learning how to use the proper programs. I guess it would be a bit easier for someone like Ivan, that has practically rewired the whole board, and is pretty familiar with the design, to re-design the board from scratch. But still requires a lot of time, that, probably no one, will pay for.

 

[HeyManslowdown97]

me too using same caps for output in my 4495 dsd. they are kinda warm but not too syrupy. more of analog timbre which is contrary to stock re3s. also they have very well resolution and imaging too .

Yea- if they really are “stock re3s” the real Nichicon FG’s used for the Opa275 I have heard are pretty rad sounding.

I replaced Op275 with an Opa2107 and it sounds pretty good to decent with the stock FGs but the stock re3s blow! I was listening with a dual Dip8 dual to mono Opa627; it STILL sounded good b/c of the Opa627 2x but was definitely held back from its potential by the stock “re3s”- They suck and gotta go.

Any advice on the Power caps???

I just wanna replace the caps and be done with upgrade for a bit then I might replace the resistors like Ivan did with 0.1% spec near the Ak4497eq since it’s the brains to entire operation. I’m not do major work on the soldering on the PCB Board it’s just not worth the aggravation !

“Too syrupy” Love it haha

 

[HeyManslowdown97]

I think that I don't prefer warm sound signatures. But I don't have a complete opinion yet. So, do you have any suggestions for a cap that is more, neutral, I guess? I might not use them at all, but they are pretty cheap, and they are not gonna be wasted, so I am ordering them anyways.


I don't know about the iPod wheel, but I think I read a while ago, that it is possible to put a volume knob, but can't recall anything more specific. Maybe the other guys know.

And now, onto the pcb thing. I think that the problem is not the cost of printing such a board. Many of the upgrades that have been done here, come close, if not surpass, the cost of the actual player.
The problem is, that it is not that easy to design an actual board (that is dac-amp combo, has 2 outputs, and needs to be small) without proper knowledge. Electrical engineers take whole classes regarding pcb designing and learning how to use the proper programs. I guess it would be a bit easier for someone like Ivan, that has practically rewired the whole board, and is pretty familiar with the design, to re-design the board from scratch. But still requires a lot of time, that, probably no one, will pay for.

I’m with you to a certain point. I don’t think you have to use software to design it as it can designed on paper. (I don’t how to do it but I would be able to follow a scheme especially if the shapes of the parts are baked on the board)

As far as the engineers are concerned the biggest challenge is design semiconductors. The rest of it A/B testing with endless amount of budgets they can get away with using cheaper components much like the Zishan Dsd since it’s all about the semiconductor. Surprisingly, China can’t beat the West with Designing their own superior chips. If you noticed most if not ALL semiconductors are made Taiwan, Korea, Philippines and Singapore. That’s by design! Not to get too political but that what the TPP was all about. China can’t design them so they cyberattack and hack the companies to steal the IP and then attempt to copy it.

The boards themselves all you need is an understanding of electronics/electricity and basic Principles. There are several people on this thread that already know how to decrypt the datasheets and AKM also opensourced specs to their semiconductors.

It’s companies like Apple, Samsung, Sony, etc that patent their boards so it’s almost impossible to get a diagram of their circuit designs and also illegal. Apple is the worse because they glue parts to circuit boards and use special screws to make it also impossible for third parties to fix their products. Here in the states it’s changing state by state are passing Right To Fix Legislation so you to end electrical waste and more importantly to give people the ability to learn. Coals Miners know basics electronical Principles to design boards. Americans have always been tinkers make stuff in their garages.

Scandinavians are leading the change. In Sweden they actually give you Tax cuts for repair shops and for repairing you own stuff. It needs to happen here! Ok, now I’ll step off my soapbox. As far as selling your PCB boards or products that’s entirely different argument like quality control, scalability and successful ad campaigns. I’m not interested in that just wnnn make a device that I can enjoy and be proud of making. That’s my two cents anyway...

 

[Ivan TT]

Ivan- I saw you took the Power Caps out what are they meant for and what did you replace them with aluminum can ones???

It was part of experiment. SMD Electrolytic power capacitors are VERY tricky to remove and the damage to PCB is very likely.
They are 26uF, so the total capacitance is 78uF but ESR is reduced due to parallel connection and they are known as " bulk capacitors" providing charge when opamps/buffer have to deal with sudden increase of level and need to draw current from the power supply, which may not be able to react quickly enough.
But how much charge is really needs to be available is tricky to estimate (depends on LOTS of factors).
Most datasheets don't go above and beyond 10uF value (as such peaks are usually short-lived), so my 900+ uF on each rail is a bit extravagant

 

[HeyManslowdown97]

It was part of experiment. SMD Electrolytic power capacitors are VERY tricky to remove and the damage to PCB is very likely.
They are 26uF, so the total capacitance is 78uF but ESR is reduced due to parallel connection and they are known as " bulk capacitors" providing charge when opamps/buffer have to deal with sudden increase of level and need to draw current from the power supply, which may not be able to react quickly enough.
But how much charge is really needs to be available is tricky to estimate (depends on LOTS of factors).
Most datasheets don't go above and beyond 10uF value (as such peaks are usually short-lived), so my 900+ uF on each rail is a bit extravagant

Yea they look tricky. What’s also tricky is that you have to do all the calculations ahead of time. If it buffers why isn’t there a buffer amp like on the Z3 or is there?! If not can you put a buff amp to regulate the values so make “act” more predictable??? I think I would approach it based on an opa amp or points of references or hubs so you’d have to first start at where your input power is going to be for the op amp to the lead the circuitry towards that Opa (hub) than you take it from that starting point to the next etc, etc but you first have to start at where your beginning, middle and end points and follow along checking with the multimeter to check if all paths are hitting their metrics based on the datasheets.

The only part I’m a bit confused about is how does the actual paths work with the Akm chip and you’ll need to make sure all paths if each function path is circuit correctly. It’s a lot of meticulous planning every step. But you have the overall concept in mind. Like you basic your PCB on the opa1622. I saw that you read certain paths via wiring terminals and you gotta be careful not mess up the voltages or function to each path.

I’d like to base my PCB on the Opa627 chip with dual mono Channels like the Op275 on the Zishan Dsd. The AKM4497eq chip is 2 channels and the AKM4499 will be 4 channels I’m curious how that would sound. It’s too bad you can split single amps or dual amps of different chips just doesn’t work logically unless the chips operate at close to equal value??!

My goal is to make a two AKM4497 with two independent chips per channel on two boards but that’s gonna take some planning for it to be on a portable sizes unless DIYINHK which would be a bad idea to follow a PCB already schemed to learn how it works but there’s a chance of being passive if it’s all mapped out for you with components that all you need to do is solder them on!

 

[Ivan TT]

I think I would approach it based on

Personally I started small and tried basic stuff, opamp rolling and changing caps that were easy to solder (sometimes experience proved me SOOOOOO wrong!)
Then it escalated from there quickly
Yet I don't think I'm in position to provide any helpful input as you ideas (as great as they are) are way beyond my knowledge and experience, sorry