ESS Sabre Reference DAC (8-channel)

[abzug]

http://blog.stereophile.com/ces2008/011008ess/
134 dB SNR and -118 dB THD are impressive, but I find some other things in the white paper more interesting, such as the discussion of dynamic element state space modulation by transients:
http://www.esstech.com/techsupp/sabrewp.pdf
The time domain interpolation for SRC is reminiscent of what Anagram does in their DSP-based solution.
Too bad no mention at all of how they achieve their supposed 100% jitter rejection.
Looks like it should be easy to DIY with because it takes S/PDIF input and doesn't need that much around it on the digital side, and can be used as either voltage or current output due to the medium output impedance.

[abzug]

Waaait a minute! dusfor99 weren't you at ESS? I see a Dustin Foreman nametag in that Stereophile photo! LOL!

[InfiniteGain]

Hi,

Does anybody know where to get hold of a unit or two of the ESS Sabre Reference DAC? The minimum dynamic range is 128dB!! THD better than -112dB any frequency.
http://www.esstech.com/products/digi...italaudio.shtm

Its the worlds best measuring DAC and supposedly the best sounding. The thing is, the DAC handles PCM, DVD Audio, SACD etc with unheard of quality and almost total lack of jitter. I was wondering if anybody may know how we can get our hands on them?

Thanks,
InfiniteGain

[GestaltH]

I was interested in this DAC too, so I hope someone has a resource of where to obtain them. It looks like they will be $29 each (@1000 units) according to a few articles online. Thats pretty pricey for a DAC, but being 100% jitter free (according to them) and some of its other properties make it look worth the money. I think I remember reading something about a voltage out also....

[GestaltH]

Hmm....

Looked it up and ESStech lists their American "Authorized Distributor" as Shaw Electronics (http://www.shawelectronics.com). However, their "request quote" page doesn't have a submit button. The submit button on their "request info" page produces an access denied error. And, when you email the address listed under the "contact us" page, the email gets returned. Also, trying to contact sales at ESStech directly via phone results in no answer and a full message box....

So, I have no idea how to figure out how to get some of these since I can't contact them or their distributor.

[dusfor99]

Hi Abzug,


Yes that is me. hmm, never thought my picture would be linked on this site. I have really not been following the DIY site closly for a long time since ive just been so busy doing derivative parts of the DAC. I will try to keep up with it more often now that people seem to have some interest in the part.


CLD

[InfiniteGain]

The initial article I saw said they were only distributing in batches of 1000 at $29 each! I was hoping somebody re-distributes in smaller quantities. Even if I have to buy 5, it works out quite favourable for me in the UK with the current exchange rate.

[InfiniteGain]

Yeah, I already have noticed. But in answer to your question, his account doesn't accept PMs or email through the website - so unless Dustin chooses to read this thread or the one you started and provide an answer, we cannot ask!

[David Davenport]

Hi Dustin,

I tried contacting you through your tech support but I guess you didn't get the message. Would you please contact me?

Thanks
Dave Davenport

[abzug]

OK I emailed him about it.

[dusfor99]

HI All,


I had no idea that people would be talking about this part on these sites. But it looks like its happening. So here is the scoop. The part is 29$ or something (honestly, that markiting are and I dont get too involved in that) but now that the DAC is officially announced, I was hoping we could give out some boards and get some feedback on them,, Perhaps even some pointers from the experts (you guys) since its obvious there is a ton of experience out there. So basically im saying I will give boards to people that are interested in reviewing the part and want to give me any feedback (posative and/or negative). I dont think Ill be able to send out 50 eval boards, but certainly a few should be no problem. Ross L from this site has the eval board and has pointed out that the sound can be much improved by chaing the el-chepo Xtal on the board, to a low jitter clock. He has said the difference is night and day, this is the kind of feedback I really appreciate. Well if anyone is interested in a eval board, please send me a personal message.

[dusfor99]

I am going to get the DAC page of our website changed. Looks like everyone is having trouble to get any info or contact info for the DAC. I will get the website updated and hopefully sort out this mess.

[Ipanema]

Hi dusfor99,

Your email function is not turn on.

Thanks.

[InfiniteGain]

Same here - I cannot send you email/PMs Dustin!!

I will have to wait until retail or a group buy is under way. I would love a chip now but I am getting married next month and so wedding/honeymoon plans will prevent me tinkering (with the DAC) and providing feedback in a timely manner. But if I can buy one-to-ten at earliest convenience that would be OK for me.

Thanks.

[borisov57]

I would love to try ES9008 dac. I have AK4396, AK4397, CS 4398 and PCM1794 modular dac to compare with.

Best regards

[InfiniteGain]

Originally posted by borisov57
I would love to try ES9008 dac. I have AK4396, AK4397, CS 4398 and PCM1794 modular dac to compare with.

Best regards

Which do you like best so far? What commercial CD players you like with these DACs?

I used to own a Chord DAC64 which was amazing on detail, resolution and tonality, but (with Chord amps too) it was too thin on depth and soundstaging. Yet when changing the amps for a Musical Fidelity KW500 the whole thing sounded jaw-dropping. Cables were Nordost Valhalla and speakers were Wilson Benesch ACT.

The best integrated CD player I ever heard was /is the Linn CD12 which is now supposedly bettered by the Linn Klimax DS wireless mediastreaming DAC. I am quite fond of Naim timing and its raw/live feel, as well as stuff from Accustic Arts, but not much else. In the cheaper stakes, I like late 90s Cyrus, Arcam and Meridian components. Meridian portrays the most bandwith, but Cyrus has the better drive and dynamics (particularly bass) to my ears. Arcam is simply a very good, more affordable all-rounder. Meridian use Crystal DACs, Cyrus use TI/BB and Arcam use Wolfson. I've heard good things about Analog Devices AD1955 but I've never heard a player with an AD DAC. Chord and recording studios have a bit of an affinity with AKM. I also heard a Burmester CD player and I don't know what that had inside, but it was the CD006 going into a Hovland pre-power combo on Eben Acoustic speakers in a Nordost Valhalla demo - that was very very good.

My listening to Musical Fidelity's top-end equipment has given me a slight leaning to tubed outputs in things, and so the Lampizator now intrigues me for using in place of a discrete output stage using op-amps and lots of components. Unfortunately, MF do not like making integrated amps with balanced designs. However, a DAC with on-board volume control into a power amp with balanced inputs could be absolutely stunning.

So the reason for my inquiry into this Sabre DAC is: I am looking at testing the PCM1794 in dual mono into a Lampizator styled tube circuit. If this Sabre Audio DAC is available, I will try and design something to compare the DACs into a tube I/V output stage. Based on my experience with high end components, I cannot imagine anything sounding better. However, I haven't made any complete DIY DAC components and was wondering what you like about each of the DAC chips?

Thanks,
InfiniteGain

[borisov57]

Hi,

All DACs sounds good. But if I must choose only one, it would be PCM1794 with resistor I/V. This is the one, that I listen to the most. Very close was AD1955 ( I blowed one channel ). AD is maybe a bit more transparent and with bit faster bass, but less quantity. Similar to AD is AK4396. It is very detailed. But I prefer PCM and AD, they seems more lively and dynamic. CS4398 is darker than AK4396, maybe more musical. AK4397 is strange, it is very good, it is the only DAC that played more than an hour on speakers and my wife did not turn down the volume.
All dac measures about the same, best SNR has PCM1794 with active I/V and lowest THD AD1955, but I am at limit of my measuring analog to digital converter.

[rossl]

The title of this thread may be a little misleading...

The Sabre is an 8 channel DAC,,, but it doesn't have to be an 8 channel DAC.

The part will configure for stereo and can have 4 channels summed for the left and 4 for the right.

Each channel is differential with a dual DAC. So, there are 16 DAC output pins in total.

I posted these links in another thread, they probably should be included in this thread.

http://blog.stereophile.com/ces2008/011008ess/

http://www.esstech.com/techsupp/sabrewp.pdf

[Dougie085]

If we could get a group buy together for these I would easily be interested in 3-4 chips. Of course that would require actually being able to contact the distributor.

[InfiniteGain]

Yes, it's a bit of a marketing disaster to have umpteen press articles stating how great it is, some in technical audio engineering circles and some in audiophile circles (like Stereophile) and then have nobody able to contact the company, or evaluate one as an engineer, or a consumer.

Whoever planned the marketing on this clearly was under-prepared and needs a slap upside the head!

[abzug]

Originally posted by borisov57
All dac measures about the same, best SNR has PCM1794 with active I/V and lowest THD AD1955, but I am at limit of my measuring analog to digital converter.

Not really. Did you measure linearity? Did you measure settling time? Did you measure jitter rejection?

Anyway, I talked to Dustin on the phone earlier and I have a bit more info: external clock can be used after all, the filter shown on the diagram on the outputs is not switched capacitor but a programmable notch filter, the jitter filter has bandwidth < 0.1 Hz, and the digital filter is 256 tap FIR.

[Dougie085]

Is there a PDF somewhere that shows the pinout of the chip? Can't seem to find one.

[ESS_Blammo]

Pinout of which chip?

[Dougie085]

This new DAC.

[nogoodboyo]

Hi DustFor99,

Please consider me for an eval board.

I currently have: AD1955, PCM1798, WM8740, TDA1543 (Active I/V) and the DAC in PCM2707 for comparison.

My Audio System consists of various SS amps, Tube Amps, SS pre-amps and Tube Pres. Horn, Electrostatic, Full-range and "conventional" speakers.



Thanks

Andrew

[borisov57]

Hi abzug,

SNR results for all DACs were from 116.7 to 118.1 dB and THD 2V RMS into about 500 Ohms were between 0.0004 to 0.0009%.
Did you measure jitter rejection?

Best regards

[abzug]

What frequency did you measure at? THD generally increases when you get above 10 K, and a lot. But I don't see this for this DAC.

Looking at detailed measurements PDF sent to me by ESS, claiming measured by a third party, THD+N vs jitter starts at least 15 dB better than top DACs from the two usual suspects, to 45 dB better, depending on jitter frequencies. It's also flat, unlike the other two DACs which show increasing significantly with frequency. Also, intermodulation is lower and phase response better, and the crosstalk is 15-20 dB lower. For me the best feature in this DAC is the digital filter.

[borisov57]

Yes, measured figures for sabre dac looks very impressive, that is why I would love to try it. My result for THD are for 1 kHz, 2V RMS driving 500E input impedance AD converter. Bandwidth is 20 kHz.

[Dougie085]

[i]PDF sent to me by ESS, claiming measured by a third party[/B]

Anyway you can post that PDF up?

[abzug]

I don't know if I have permission to post the datasheet, but on the comparisons it says I can forward them to other people interested, so if you PM me I'll email it back. However, I think it was mentioned in this thread they intend to post more data on the web anyway.

[Dougie085]

I can't figure out how to pm at all... I have email enabled so just email it to me if you can please.

[dusfor99]

Hi All,


Here is a link to the website, some more data has been posted here, but its still a work in progress.

http://www.esstech.com/techsupp/drivers.shtm

[InfiniteGain]

Originally posted by dusfor99
Hi All,


Here is a link to the website, some more data has been posted here, but its still a work in progress.

http://www.esstech.com/techsupp/drivers.shtm

I have to say, that is a pretty complete collection of stuff there - far better than a basic data sheet. You guys really have considered pretty much everything!

[rossl]

Originally posted by dusfor99
Hi All,


Here is a link to the website, some more data has been posted here, but its still a work in progress.

http://www.esstech.com/techsupp/drivers.shtm

Hi Dustin,

Glad to see all that information is up on the web site.

I wonder if you could clarify something. I have only tried stereo SPDIF on the demo board. But I'm still a little confused.

The White paper mentions setting the part into stereo mode and 8 channel mode. But the white paper and the data sheet are not really clear on the mode setting. How did you do that?

There may be something in the docs that I missed. Looking through the data sheet and it's registers, the data sheet says that it will auto detect PCM and DSD. The only register setting for modes is to set 4-channel mode. There doesn't appear to be a way to use the registers to force stereo or 8-channel mode.

It automatically configures for stereo if I input stereo SPDIF on data 1, which is what I am doing right now. I am OK with this so far.

Will the part automatically configure for 2 channel mode if I input I2S on only the first I2S input? I assume I do not need to input the same data on the 4 I2S inputs? I can just leave them alone, pulled down with the resistors?

It appears that I have to set the register for 4 channel mode and input I2S on the first and third data lines for 4CH.

Will the part automatically configure for 8 channel mode if I input I2S on more than the first I2S input? Then set the registers to 4CH if that is what I want?

Does the same go for stereo and multi-channel DSD?

I suppose I could perform some experiments on the demo board to answer these questions, but I am hoping that you have a quick answer.

[dusfor99]

Hi Ross,

I have a "quick" answer, buyt maybe no the one you wanted. Anyways here it is.

SPDIF input:
automatically goes to @ channel mode, you jsut need to parallel the outputs together on the PCB. Also, you must set the regsiter bit to activate SPDIF mode.

SERAIL/DSD mode.
This is the default mode upon power up, the chip will autodetect between these 2. Now for configuring between 2-8 channel part, there is lots of configureations in there I haven't mentions in the datasheet since the 6 bit noise shaper worked out the best. Register 15 that is not talked about can actually set the quantizer to be of 6/7/8or 9 bits. ( Oh man, Im really opening a HUGE can of worms here I might regret). When making the prototypes I thought that 7 bits was going to be the best tradeoff, however, 6 bits works better for THD+N and DNR. But since I know you guys will want to tinler with it, I might as well tell you what the chip is capable of.

One way to add DAC together is everone on this site is aware if is to simply duplicate the input to many dac's and sum them up. What this buy, well I can get 3dB DNR improvemnt everytime to double the amount of DAC (in theory) Basiaclly uncorrelated noise add RSS and signals add normaly. Antother way woud be to actaully use a larger bit quantizer and route the signals from the quantizer to 2 DAC's, but the noise shaper is actaully now has an extra bit in it. This chip does both. You can simple dupilicate the data input input header and then add up the outputs in an analog circuit on the board, or you can program the chip to use a larger quantizer. Doing this, prevents the need to send the same data in all the inputs since now a certain DAC channel is routed into 2 DAC oututs. (man im already regretting this, ohwell, here goes) The DAC is normally a 6 bit quantizer, with the DACx being the summation of the 6 bits, and DAxB being the summation of the inverse of the SAME 6 bits. This is the best all round perfoamnce mode, and this is why the datasheet say reg15 needs to be set to 8'b00000000. Setting this regsiter to 8'b01010101, which by the way was the mode I thought would work best base on my prototype design, and thats why its the default configuarion, the DAC becomes a 7 bit quantizer (thus reducing out of band noise) and I simple divinded up the 7 bit number coming from the qunatizer into 2 6 bit numbers and inverted 1 of them. Then I send off these new 2 6 bit numbers which the differnce is mathematically identical to the origanal 7 bit number from the quantizer and shipped them off to the analog section. This also results in 8 channels at the input being route to 8 channel at the output. Now, lets go further (were only 1/2 down this road) . if you set the reg 15 to be 8'b10101010 then you get a DAC with an 8 bit quantizer, out of band noise decreses more and so on. Now I shut off 1/2 the internal logic since its not requires, only inputs 1,2,5,6 are now needed since now an 8 bit ouput can be spliced into 4-6 bits numbers. (Channel 1 got merged with channel 3, 2 got mergerd with 4, 5 got merged with 7, 6 got mergerd with 8. This is to keep the mergered channels analog secions as close as possible for device mathing in the chip.) This gobbles up 2 analog sections per input now. That is why 1/2 the figital section is shut off. So this can make you a 4 channel DAC while putting data into only the first 4 channels. Ok, lets goes further, how about a 9 bit quantizer, sure why not, Setting reg 15 to 8'b11111111, now I shut of 6 of the channals internally and only the channels 1 and 2 inputs are routed to about analog sections. Well its probably obvious by now why, but here it is again. 1-9 bit number can be broken into 8-6 bit numbers. Now route the 8-6 bit numbers to the analog sections (remeber that each section is DAC and DACB so there are 2 analog sections per DAC or 16 total in the chip, I think someone already pointed this out in one of the threads on this site) so now with each input taking 8 analog secitons, that is 2 channels.

Alright that was fun. One might ask, why have 8 bits to represent swtiching between 4 states, should that only need 2 bits. Sigh..............., yes. Here goes again. If you set reg 15 to 8'b00000010 something else happens. Now its 7 channel DAC.

Reg 15 is mapped like this

r15 [7:6] q_size_68; //2'b00 => Quantizer = 6 bits
//2'b01 => Quantizer = 7 bits
//2'b10 => Quantizer = 8 bits
//2'b11 => Quantizer = 9 bits

r15 [5:4] q_size_24; //2'b00 => Quantizer = 6 bits
//2'b01 => Quantizer = 7 bits
//2'b10 => Quantizer = 8 bits
//2'b11 => Quantizer = 9 bits

r15 [3:2] q_size_57; //2'b00 => Quantizer = 6 bits
//2'b01 => Quantizer = 7 bits
//2'b10 => Quantizer = 8 bits
//2'b11 => Quantizer = 9 bits

r15 [1:0] q_size_13; //2'b00 => Quantizer = 6 bits
//2'b01 => Quantizer = 7 bits
//2'b10 => Quantizer = 8 bits
//2'b11 => Quantizer = 9 bits

where q_size_xx is the "Quantizer size of the coresponce internal DAC.

so setting reg 15 to 8'b00 00 00 10, sets DAC 1 and 3 into 8 bit mode, this means that channel 1 and 3 are megeges, and all others are independent. So data on input for channel 3 will be ignored. If you set the reg 15 to 8'b00 00 10 00, then channels 5 and 7 are merged. and you again have a "7 channel DAC" Notice that the merging. all happens on the same side of the chip. For example, DAC 1 and 3, 5 and 7 are on the right side of the chip. DAC's 2 and 4, 6 and 8 are on the left. This is for the device matching again. Now what if you want to set all the "Left" DAC's (2/4/6/8) to be 1 mother 9 bit noise shaper, and set the other side of the chip to be 4 indepentdace DAC's, thus making a 5 channel DAC. Well set reg15 to 8'b11 11 00 00, for 1 9 bit DAC + 4-6bit DAC's, or even 8'b11 11 01 01 for 1-9bit DAC, and 4-7 bit dacs. I think im going to stop here.

So all that being said, I found that simple using 6 bit mode and running the same data into the inputs and paralleing the outputs, the THD+N and DNR , for the general case, was better, however there are some modes you can tweak and get better perfomance with the other seting, but were taling same difference of 1dB of so.
With that being said, I bet you all now can appreciate why I just chose to say reg 15 set to 8'b00 00 00 00 and be done with it. But I know you guys will tinker with it, so I wanted to let you know, most of our cusmtoners though, really do not want this kind of detail.

[Russ White]

I would very much like to evaluate the chip. I would be doing my own layout so I just need sample chips, not an eval-board. How can the chips be purchased?

Thanks!
Russ

[rossl]

OK. Thanks for the answer, Dustin. That will give me something to tinker with over the weekend

[finneybear]

Com'n, Dustin, you know what we really want to know, not just those info on the surface...

So how the DEM is done? And the "summation" is done?

[dusfor99]

finneybear,

Sounds like you want the schematic, the GDS database, RTL code, and even a picture of the silicon. You know I cant do that, it may be my design, but its not my money put up to build the chip. So I can answer questions about the general nature, but to say exaclty what inside the chip, there is no way ill be allowed to do that at this point.

Sorry about this, but thats the way it is.


Thanks

Dustin

[finneybear]

No no Dustin, I am not interested in your RTL or behavioral codes.

Cant you talk a bit more about the patterns to do the assignment in DEM or show us a simple diagram about how the outputs are put together? You know, things people can discuss in a conference?

[finneybear]

BTW, dont get too nervous. I am not doing any DAC chips, or even audio/video chips now. Not involved in any audio/video/consumer designs either. I am more than happy to see finally someone would bring out something to beat out TI and ADI, in fact.

[Dougie085]

Be nice if we could get a PCB designed for this for DIY use I'm extremely interested in building a 2 channel DAC using this chip. Or even an 8 channel possibly. How do you pass DSD to the DAC anyways? Is there a firewire input capability?

[dusfor99]

http://patft.uspto.gov/netacgi/nph-P...+Forman&d=PTXT

[finneybear]

Read those patents a few days ago already. Looks like these are all you can reveal now.

[Russ White]

Originally posted by Dougie085
Be nice if we could get a PCB designed for this for DIY use I'm extremely interested in building a 2 channel DAC using this chip.

This is exactly what I want to do, but I need to be able to purchase some samples. Still no answer to my sample question...

I would very much appreciate being able to buy a few samples.

Thanks!
Russ

[dusfor99]

Hi Russ,


I have contacted marketing to find out the process, I will put the into on this thread ASAP.

[Dougie085]

Yes a 2 channel DAC with SMT parts I want to try out populating an SMT board.

[Russ White]

Originally posted by dusfor99
Hi Russ,


I have contacted marketing to find out the process, I will put the into on this thread ASAP.

Thank you. I am clearing out some time to start the layout.

Cheers!
Russ

[rossl]

Originally posted by Russ White



Thank you. I am clearing out some time to start the layout.

Cheers!
Russ

Hi Russ. I am working on a schematic for a layout also. I have been 'experimenting' with the demo board.

How are your skills at the PIC micros? This part will need a I2C controller on board. I am thinking a PIC16F677 at minimum, maybe a PIC16F882 if I want it to do some other processes.

[rossl]

Found this:

http://www.cmoset.com/uploads/4.2.pdf

It looks like Dustin has been giving some seminars !