AKM AK4490eq DAC chip

[Blizzard]

Hi guys,

Over the last couple of days I've been listening to a new DAC I had custom built using the AKM AK4490eq DAC chip. It's a state of the art design using ultra low phase noise clocks (-114Dbc @ 10hz) and 100% discrete circuity. Not a single IC in the signal path besides the DAC chip, and the output stage runs in pure class A. So far the only interface I have connected to it is a very well implemented Xmos based USB interface. All I can say is this is one hell of a chip when supported by SOTA circuitry! It put's my Mirus to shame, even when it's playing tracks from the SD card transport. The sound is so pure it's astonishing. The PCM is the best I've heard, especially when upsampled to 24/384 with HQplayer. This chip also has a DSD direct bypass mode. This mode bypasses all the internal processing for the purest DSD possible from an IC chip. THE PCM is so good upsampled to 24/384 with HQ player that it's hard to beat. But upsampling to DSD 256 with HQplayer, allows complete bypassing of all the chips internal processing. Is it better? I think it would be a matter of personal taste and the computer used to do the processing. Way more CPU processing power is required to convert on the fly to DSD 256. Where as my broadwell I3 NUC can upsample to 24/384 with only 5% CPU load. So I suppose that is a major factor.

I can't wait to hear this DAC with a SOTA Ravenna interface!!!

 

[NorthStar]

? http://www.ebay.com/itm/Assembled-A...main_0&hash=item339ff24cf1&afsrc=1&rmvSB=true

 

[Blizzard]

? http://www.ebay.com/itm/Assembled-A...main_0&hash=item339ff24cf1&afsrc=1&rmvSB=true

The setup is a bit more elaborate than that.

 

[NorthStar]

? http://www.akm.com/akm/en/product/detail/0054/

The Esoteric K-01 and K-03 use that DAC.

 

[Blizzard]

? http://www.akm.com/akm/en/product/detail/0054/

The Esoteric K-01 and K-03 use that DAC.

I'll tell you right now that it put's ESS's current Sabre offerings to shame Maybe not on paper, but in sound yes.

 

[NorthStar]

I'll tell you right now that it put's ESS's current Sabre offerings to shame Maybe not on paper, but in sound yes.

I bet it does: http://www.theaudiobeat.com/equipment/esoteric_k01.htm

 

[Blizzard]

I bet it does: http://www.theaudiobeat.com/equipment/esoteric_k01.htm

that DAC uses the older and far inferior AK4399 chip

 

[NorthStar]

that DAC uses the older and far inferior AK4399 chip

Eight per side; in the K-01 (older model)... you are right. But it's the configuration of eight of them per channel that helps...a little.

__________

And... http://www.akm.com/akm/en/product/featured/audiomarketvoices/esoteric/ ==> Those use the AK4490EQ DAC. ...And...scroll down.

For fun: [POST]303615[/POST]

I have no doubt...this should be my aim. Solid build, reasonable price (relatively), and company excellence.

________

1. http://www.esoteric.jp/products/esoteric/k01x/indexe.html -> Click on 'Features'
2. http://www.esoteric.jp/products/esoteric/k05x/indexe.html => Click on 'Features'

 

[Blizzard]

Eight per side; in the K-01 (older model)... you are right. But it's the configuration of eight of them per channel that helps...a little.

__________

And... http://www.akm.com/akm/en/product/featured/audiomarketvoices/esoteric/ ==> Those use the AK4490EQ DAC. ...And...scroll down.

For fun: [POST]303615[/POST]

I have no doubt...this should be my aim. Solid build, reasonable price (relatively), and company excellence.

I'm thinking of dedicating 8 of these chips in monoblock mode for my active 4 way speakers. 1 chip per driver. All chips synchronously clocked to -114DBc 10HZ phase noise masters.

 

[NorthStar]

I'm thinking of dedicating 8 of these chips in monoblock mode for my active 4 way speakers. 1 chip per driver. All chips synchronously clocked to -114DBc 10HZ phase noise masters.

Eight DAC chips (stereo) per channel is sixteen DACs per channel (32 outputs | +/- ).
The Esoteric K-01X only uses eight DACs (AK4495SEQ) per channel (four stereo); still sixteen outputs (+/-).

? You should hear a "silent dark black background". ...Your own shadow should be noisier than that. ;-) ...Try not to move while listening.

 

[Blizzard]

Eight DAC chips (stereo) per channel is sixteen DACs per channel (32 outputs | +/- ).
The Esoteric K-01X only uses eight DACs (AK4495SEQ) per channel (four stereo); still sixteen outputs (+/-).

? You should hear a "silent dark black background".

The thing about DAC chips is below 100HZ is much harder to do. You can get far better performance out of a DAC chip if your only sending 100HZ up to it. It will only be the woofers that see the stock specifications of the chip. The midbasses, mids and tweeters will see far greater performance. Same goes with the output stage.

Those DAC's look real nice. But the AK4490 is a better chip than the 4495. The reason the higher end K-01X uses the 4495 is because it was released before the 4490 was. I bet the K05-X is one killer DAC for the price.

http://www.musicdirect.com/p-349026-esoteric-k-05x-sacdcd-player-dac.aspx

 

[NorthStar]

The thing about DAC chips is below 100HZ is much harder to do. You can get far better performance out of a DAC chip if your only sending 100HZ up to it. It will only be the woofers that see the stock specifications of the chip. The midbasses, mids and tweeters will see far greater performance. Same goes with the output stage.

Those DAC's look real nice. But the AK4490 is a better chip than the 4495. The reason the higher end K-01X uses the 4495 is because it was released before the 4490 was.
I bet the K05-X is one killer DAC for the price.

http://www.musicdirect.com/p-349026-esoteric-k-05x-sacdcd-player-dac.aspx

.
...And the K-07X --> http://www.esoteric.jp/products/esoteric/k07x/indexe.html

? http://www.musicdirect.com/p-349027-esoteric-k-07x-sacdcd-player-dac.aspx

 

[audio.bill]

Two new DACs just being released which both use dual AKM AK4490EQ DAC chips (one chip per channel) are the Bryston BDA-3 (US$3,495) and the Hegel HD-30 (US$5,000) which is also a streamer. The Bryston uses a discrete Class A output stage, and the Hegel a new custom discrete low phase noise clock circuit. Interesting times indeed!

 

[Blizzard]

Two new DACs just being released which both use dual AKM AK4490EQ DAC chips (one chip per channel) are the Bryston BDA-3 (US$3,495) and the Hegel HD-30 (US$5,000) which is also a streamer. The Bryston uses a discrete Class A output stage, and the Hegel a new custom discrete low phase noise clock circuit. Interesting times indeed!

Should be excellent DAC's. Yes discrete pure class A is the only way to go. I can't listen to IC opamps anymore after hearing the difference of switching to top quality fully discrete class A circuits. And of course ultra low phase noise clocks are essential.

 

[Ric Schultz]

The latest Schiit Bifrost DAC uses the 4490 and costs $400 and has a discrete output stage. I know their power supplies and output stages are not SOTA but pretty decent. They have a higher cost multibit option that they feel sounds better. The Multibit option uses 16 bit ladder DACs and closed form digital filter.

 

[Blizzard]

The latest Schiit Bifrost DAC uses the 4490 and costs $400 and has a discrete output stage. I know their power supplies and output stages are not SOTA but pretty decent. They have a higher cost multibit option that they feel sounds better. The Multibit option uses 16 bit ladder DACs and closed form digital filter.

Yeah several choices ranging from $30 to $22500 using this chip. I think that just goes to prove there's much more to a great DAC than just the chip. But at the same time as I'm confirming right now, this chip is very good when used in a very well implemented DAC with SOTA circuitry. The raw wholesale parts cost of the class A output stage in the DAC I'm listening to, cost more than $400. And that doesn't include engineering costs.

 

[Ric Schultz]

Blizzard,
We are having rain today....no snow.
What discrete output stage are you using? Burson, Dexa, Forssell, custom? You can buy a whole 4490 DAC with usb from China with coax and usb for $100 and tweak it out. Are you using exotic regulators? Who's clocks? Crystek?
Ric

 

[Ric Schultz]

I see you were replying while I was typing.....maybe we can repeat it again....he he. I use a zero feedback super simple fet buffer on a voltage out DAC. This is the best discrete stage I have ever heard....and the most simple. You use a LSK170 or two in parallel and one or two more as its current source. You use a single pole filter on the output of the DAC (5 k resistor in series and then a 330 pf cap to ground along with a 1meg resistor to ground)...then through the single fet and use a coupling cap on the output. Even one lsk170 will give 50 ohm output impedance...two in parallel will give 25 ohm. No other parts in the circuit. I use discrete shunt regulators....You can see what I do on my website page: http://www.tweakaudio.com/EVS-2/Oppo_105_Mods.html The modified Wima caps with WA Quantum chips make great output caps....I use a cheap polyprop in parallel to get to 2 plus uf. The Wimas are just .33. You can parallel them. The only downside to this buffer is it has no gain. So you get one volt RMS on the output instead of the usual 2. No problem if you are running a preamp but if running directly to amps may not be enough gain.

 

[Blizzard]

Blizzard,
We are having rain today....no snow.
What discrete output stage are you using? Burson, Dexa, Forssell, custom? You can buy a whole 4490 DAC with usb from China with coax and usb for $100 and tweak it out. Are you using exotic regulators? Who's clocks? Crystek?
Ric

It's a custom stage. It uses very high end components and has very high output capabilities in order to drive Hypex NC500 amp modules direct with no other buffer stage. It's capable of 24Db of gain with a noise floor of -140db and THD+N of 0.0003%, running in pure class A. Very high end LDO's are used to power the output stage. It's a SOTA cost no object design, engineered by the best in the business.

I'm using NDK clocks that have been individually sorted and tested. The top 1% of a reel of 500 were used in this DAC. The NDK clocks can be extremely good. But the phase noise can vary +- up to 15db from clock to clock. Very few DAC manufacturers actually test their clocks individually. It's extremely costly and takes 2 hours for each clock, as well as a $100000 machine.

Here's the actual phase noise plot of the clocks that went in this DAC.

View attachment 23251

 

[Blizzard]

I see you were replying while I was typing.....maybe we can repeat it again....he he. I use a zero feedback super simple fet buffer on a voltage out DAC. This is the best discrete stage I have ever heard....and the most simple. You use a LSK170 or two in parallel and one or two more as its current source. You use a single pole filter on the output of the DAC (5 k resistor in series and then a 330 pf cap to ground along with a 1meg resistor to ground)...then through the single fet and use a coupling cap on the output. Even one lsk170 will give 50 ohm output impedance...two in parallel will give 25 ohm. No other parts in the circuit. I use discrete shunt regulators....You can see what I do on my website page: http://www.tweakaudio.com/EVS-2/Oppo_105_Mods.html The modified Wima caps with WA Quantum chips make great output caps....I use a cheap polyprop in parallel to get to 2 plus uf. The Wimas are just .33. You can parallel them. The only downside to this buffer is it has no gain. So you get one volt RMS on the output instead of the usual 2. No problem if you are running a preamp but if running directly to amps may not be enough gain.

I'm not the engineer behind this output/input stage I'm using. So I leave all the details to the pro's. But based on what I'm hearing right now, the pro's know what they are doing. So I'll just be content with what they have done