T+A DAC 200

[OE333]

The (optional) HDMI inputs of the DAC 200 are real HDMI inputs according to the HDMI specification. For a detailed description of the HDMI interface see: https://en.wikipedia.org/wiki/HDMI

 

The DAC200 can receive high definition PCM and DSD signals (according to the HDMI specs) over its HDMI inputs. Any DVD, HD-Audio or SACD player with a standard HDMI output can be connected to these inputs.

 

The DAC200 also supports HDMI Video pass-through from such players to a (TV)monitor and the ARC (Audio Return Channel) from TVs.

 

But clearly spoken: The DAC200 HDMI inputs are not just mechanical HDMI sockets (mis)used to receive unencrypted raw I2S signals.

 

[OE333]

On 2/6/2023 at 10:46 PM, camott said:

The specs for the DAC 200 state "High level (RCA) 0...2,5 Veff / 22 Ohms, balanced (XLR) 0...5,0 Veff / 22 Ohms".  i.e. as is common, the output is doubled for balanced output.

 

Apparently this is almost always an indication that the XLR is NOT AES48 compliant. Because, and I am paraphrasing an industry veteran here, it suggests that the pin 2 and pin 3 signals are being generated relative to ground, and out of phase with each other. i.e. effectively two single ended outputs and thus doubling output voltage. Whereas, AES48 outputs are generated relative to each other and ground is ignored .... (pin 1 being the ground as you mentioned).

 

The analog signal circuitry of the DAC200 is referenced to the analog signal ground. This conforms to AES48 (see "REF" ground in figure_3 of draft AES48-20XX).

 

The generation of the balanced audio signal is already done in digital domain - not in analog domain. So this balanced signal is not generated relative to any (analog) ground.

 

To ensure a very high immunity against electromagnetic interference and noise, the DAC200 was tested (by an accredited testing laboratory) to comply with the strict requirements of the following standards:

EN55032:2015+A11:2020, class B

EN55035:2017+A11:2020

EN61000-4-2:2009
EN61000-4-4:2012
EN61000-4-3:2006+A1:2008+A2:2010
EN61000-4-5:2014
EN61000-4-6:2014
EN61000-4-11:2004
EN61000-3-3:2013
EN61000-3-2:2014

 

Where AES48 only gives guidelines for good engineering practice but no measurable performance limits, the above standards contain measurable and verifiable specs and limits for noise immunity. As the DAC200 complies with all requirements of the above standards, it can be assumed, that it will perform well in any home and studio environment.

The DAC200 was mainly constructed to comply with the above EMC rules but of course AES48 is known to its developers and was taken into account as far as possible.

[OE333]

51 minutes ago, linuxprophet said:

I updated my DAC200 and HA200 via the wonderful MP200 and also noticed the relay clicks have stopped. To be honest, I was a little scared of the clicks, even though I believe they are relays (stand to be corrected).

 

The updates are fine and the devices purr like none other. I am simply so pleased to have purchased such delectable units.

 

 

 

Short answer: yes, you are right, the output-mute relay clicks were minimized in the latest firmware.

 

Longer answer: In the older firmware the output was muted (by relay) on every format change.

It has shown, that such muting was unnecessary on many occasions - like when there is only a change of sample rate.

So in the newer firmware the mute relay will only switch (and click) when there is a DSD <--> PCM change.

A click in this case can not be avoided, because here the whole analog signal path changes and to prevent any pops in the output signal a short muting is required.

Btw.: The reason for using a mute relay is that we at T+A believe that this is the best option for muting analog signals. All semiconductor mute circuits would increase the distortion. So we have decided to use an old fashioned (hernetically sealed gold contact) relay and accept the click in favour of lower distortion.

[OE333]

1 minute ago, jrsub said:

My DAC 200 has always only had the solenoid click when switching between PCM and DSD tracks.  Within PCM or DSD a resolution change has no click.

 

... then you already have the new firmware.

[OE333]

11 hours ago, Mist1Fu said:

And the change of intermittent input light when there’s no signal or audio is part of the update as well then?

 

... this seems to be an unintended change in the latest firmware.

The blinking light will come back with the next FW update - promised ;)

[OE333]

2 hours ago, luisma said:

Manual page 43 at the bottom says to use "either balanced XLR or unbalanced RCA connection. Do not use both types of connection at the same time."

 

Then next page 44 says "if the two outputs should be used together the input impedance of both connected devices must be at least 10 kOhm"

 

Does this means the two outputs be used at the same time with the impedance ratio consideration?

 

You can safely use both outputs together at the same time. No problem, nothing will break.

 

The impedance should be >10kOhms, because the RCA output is fed from the positive branch of the balanced output amplifier.

So any device connected to the RCA output will cause a slight imbalance of the XLR load resistance.

As long as the impedance of the device connected to the RCA socket is high enough this effect can be neglected. Hence the 10kOhms recommendation.

 

Even if you connect a RCA device with 1kOhm input resistance, it will not break anything nor will it cause audible effects.

 

 

[OE333]

On 2/10/2023 at 7:07 PM, Allan F said:

 

Any recent news about when this will be available?

 

The programming tool will be available through the T+A webshop from beginning of March. As I heard, the price will be around €100.

 

If there is a urgent need it can be ordered right now directly from the T+A service dept. [ e-service (at) ta-hifi.com ]

[OE333]

On 2/13/2023 at 3:25 AM, lsantista said:

huh, it didn't have to be like that, or did it? I mean, the physical rj45 for a stable internet connection is there. right?

 

 

 

The DAC200 is a USB / S/P-DIF and HDMI DAC. It does not have an ethernet port.

Without having an ethernet port there is no way for a direct FW update through the internet.

 

The RJ45 sockets are used for communicating with other T+A devices (like MP200, A200 etc.).

 

The possible ways for a FW update of the DAC200 are:

1.) Through a T+A MP200 streamer

2.) From a (Windows) PC through the T+A programming tool.

3.) using a MSP430 programmer from Texas Instruments

 

[OE333]

On 2/13/2023 at 3:10 PM, lsantista said:

thank you. Im sure there were other considerations into play when designing the product such that it is "difficult" to update the fw.

to be fair, the original reason I asked was because I was having trouble getting sound from the optical connection, only to find 10 minutes later I that it was disabled - which I understand is a potentially usefull and rare feature among dacs. 

 

 

 

Disabling unused inputs means getting rid of potential noise sources.

[OE333]

12 hours ago, Miska said:

 

Is it the same one I already have for DAC8 DSD, or is it something different?

 

 

No, it is different.

The DAC8DSD used the RS232 control interface for FW update, the 200 devices use the E2Link Interface.

[OE333]

To shed a bit more light on the T+A firmware update procedure:

 

All T+A devices have a proprietary control interface (called "E2Link", "HLink" or "R2Link", depending on the series). Some T+A devices like DAC8DSD, DAC200 and HA200 have an additional RS232 interface labelled "CTRL" which is intended for control of the DAC via RS232 commands.

 

In principle both interfaces can be used for a firmware update.

 

The T+A programming adaptor uses the T+A (X)Link interface for the FW update. This is because this option can be used for all T+A devices, not only for those with RS232 interface.

 

Update of DAC8DSD, HA200 and DAC200 is also possible over RS232. In this case only a SubD-9 to RJ12 cable and a COM port on the PC (or USB to RS232 converter) is required. This is the adaptor mentioned in the post by @Miska.

 

If there is a common interest in the RS232 update, I could write a little guide on this.

[OE333]

22 hours ago, linuxprophet said:

Wow!

 

This is excellent information, which only an insider can provide.

There are RS232 D-SUB to RJ45 cables available (like the ones used for CISCO Routers). Or D_SUB to USB as stated earlier.

 

I think a step-by-step guide for those who may not be too familiar with the cables or process might be handy.

 

Thank you OE333.

 

Ok, I will write a step-by-step guide on the update process.

Please wait for this guide before trying to do the update --- there are differences between DAC8DSD, HA200 and DAC200.

Especially the HA200 is a bit tricky because its RS232 interface is shared between the CTRL and the E2Link.

 

I will post some more detail here as soon as I find the time to write the guide. Please give me a couple of days.

[OE333]

9 hours ago, e.Latte said:

On 3/3/2023 at 8:44 PM, 1125FPS said:

As a happy owner of the DAC 200 I can answer some of the questions you asked. I left some unanswered. 
 

Hope this helps.

 

I respectfully request your kind and generous help for a friend GH considering DAC 200 for GH's 2nd system primarily for TV (may stream Qobuz via M-Connect.)  DAC 200 price is irrelevant to this conversation.   

 

Most of the below Qs relate to labels on DAC 200's rear panel:

 

What is SYS IN?

This is used if you have the MP 200. It allows for the MP 200 to communicate with the DAC 200

What is USB SYS?  

I have the MP 200 and in the manual it says to connect the sys in and the usb sys in. It doesn’t explain it further in the manual. I have been using my MP 200 with just the EZ link cable and not the usb.

What is HDMI OUT (ARC?)  

I believe ARC stands for áudio return channel. 

What is CTRL?  

 

What is CHARGE?  
I’m pretty sure this is to charge remotes or other devices 

 

Is there ethernet connector (appears not)?

No ethernet for streaming.

 

Is TV HDMI > DAC 200 OK?  Ditto TV optical > DAC 200?  Which performs better?  

 

Describe the method for firmware/software updates.

 

Another friend says DAC 200's DSD decoding is "unique."  If possible, please comment.

 

Thank you in advance for your kind help.  

 

 

Most questions were answered nicely and correctly by @e.Latte - thanks !

 

Here are missing answers:

SYS In is a combined digital audio and control interface for the connection of MP200 to DAC200. Audio data is transmitted from the MP200 to the DAC. Control signals are sent bi-directionally between both devices - this for example makes it possible to control both devices with just one remote control.

 

USB-SYS : same as SYS but with (future) support for higher sample rates.

 

CTRL: This is a RS232 (with 5V logic level) interface. It can be used to control the DAC from a Computer or home-automation system.

 

CHARGE: correct - this socket is used to charge the IR remote control

 

HDMI vs. optical TV connection:

HDMI-ARC and optical both use the S/P-DIF format for the audio data. So there is no difference in supported audio resolution or sample rates.

The optical connection isolates the TV from the DAC which might be an advantage in some cases (depending on your installation).

The HDMI connections is convenient if you have a SACD or HD audio BluRay player. You can play high definition audio via DAC200 and pass on the video to the TV in case you want to watch a movie. Furthermore you can use the DAC for your TV sound via the HDMI-ARC (Audio Return Channel) connection.

(*) Please note: the HDMI module is an optional extra !

 

Unique DSD DAC

The DAC200 has separate DACs for PCM and DSD. The DSD DAC is not an off-the-shelf integrated DAC chip, it is a "discrete" T+A proprietary DAC. This DAC is specially constructed for the demands of DSD signals and makes no compromises as normally PCM/DSD combi-DACs do. It has an outstanding resolution and jitter performance. 

 

Firmware Updates

Firmware updates will normally not be necessary but It is possible to update the FW through a MP200 (via the "SYS" connection). This is the easiest and most convenient way.

If no MP200 is available the FW can also be updated from a PC with the help of a T+A programming tool. This will normally be done by your T+A dealer. But the programming tool will be available through the T+A webshop in the near future for all users who want to do the update themselves.

 

[OE333]

On 3/2/2023 at 7:29 PM, Tihon said:

@OE333 would you be so kind to tell a little bit about difference between DAC200 and it's more expensive brother SDV 3100 HV?

 

I mean, it's very obvious that SDV 3100 HV has more bells and whistles built in, but I'm interested in DAC for HQPlayer only. Is 3100 really much better than 200 when it comes to converters and/or analog stage? I've noticed different output voltages and higher SNR of DAC200, which is strange. Besides this, the information on the site does little to help understand the advantages of the 3100 series.

 

By the way, SDV 3100 HV has a built-in NAA (sad that there is no such thing for MP200 or MP 2500R). How do you think, is it the best possible solution for HQP, or external high-end USB source might improve on it?

 

In principle the architecture of DAC 200 and SDV3100 are very similar and the same technology is used - like separate PCM and DSD DACs, T+A's unique true-1-bit converter, galvanic isolation between digital and analog, all discrete analog stages, etc. etc.

The differences are in the details:

• The SDV 3100 HV includes additional audio sources (like streaming client, FM/DAB tuner, bluetooth audio). In case of the DAC200 you will need the MP200 for these functions.
• The SDV3100HV has a built in NAA for streaming audio signals in highest quality from HQ Player
• Massive case design of the HV series made from up to 4cm thick aluminum plates
• Much higher weight of the SDV3100HV means better mechanical stability and vibration damping
• The SDV's case is divided into 5 different compartments for digital power supply, analog pwr-supply, control section, digital signal processing section and analog section. All these sections are heavily shielded against each other to eliminate electromagnetic interference
• The T+A 1 bit converter in the SDV3100HV has double the number of converter elements giving even better noise performance
• Both devices use the T+A "high voltage" technology  for the analog stages but the supply voltage in the HV series is still higher than in the DAC200 making the stages even more linear.
• The analog output stages in the SDV3100HV run on a much higher bias current giving an extended class-A operation range
• The SDV has a better headphone amplifier
• SDV3100HV has a special T+A proprietary connection for PDT3100HV SACD player. This connection transfers audio and clocking signals in highest possible quality and with extremely low jitter.
• SDV3100HV has higher power mains power supplies with highly sophisticated mains filtering and separate analog and digital mains inlets to connect analog and digital parts with separate mains cords to the mains minimizing coupling of electromagnetic noise from digital to the analog side.

 

All the above differences make a difference and the sound quality of a SDV3100HV is still a bit higher than the already excellent quality of a DAC200.

 

SNR performance

The measured noise performance of the DAC200 on the first look seems to be 2 dB better than that of the SDV3100HV. This difference is a consequence of the higher bandwidth of 300 kHz in the SDV compared to 200 kHz in case of the DAC200.  If the bandwidth of the SDV3100HV would also be limited to 200kHz it would give the SDV3100HV an advantage in noise over the DAC200 but we wanted to have the higher bandwidth because this improves the dynamic response and gives a more linear phase at high frequencies.

But the measured differences between DAC200 and SDV3100HV are really extremely small !

 

 

[OE333]

@Tihon

The idea behind the SDV3100HV is to make all kinds of audio sources available to the user (S/P-DIF, HDMI, USB, network, disc player etc) at the highest possible quality.

 

The SDV (and also the DAC200) incorporates an extremely precise clock which is used to re-synchronize all incoming audio data streams  - no matter of which input is used. This ensures a top of the notch jitter performance for all sources connected to the DAC.

 

Also a complete galvanic isolation is included in our DACs which guarantees that no digital noise from any source can invade into the analog section.

 

[OE333]

On 3/5/2023 at 8:38 PM, Tihon said:

@OE333 oh, and I've almost forgotten another question. Do T+A dads have same output level for PCM and DSD? Some DACs are playing DSD at lower levels than PCM.

 

Precise answer: DSD is 0.1dB louder than PCM with standard FIR Oversampling.

 

But the PCM output level slightly depends on the chosen oversampling filter (FIR, Bezier, NOS).

Generally speaking the output level differences between the different input formats and oversampling algorithms are always less than +/- 0.2 dB.

 

 

 

[OE333]

5 hours ago, Nkam said:

does the DAC 200 play true NOS in PCM mode? 
I’ve heard that it isn’t due to the nature of the ΣΔ chips.   BB I think. 
Are the first 6 bits NOS and the rest ΣΔ?

 

Asking if it is a good DAC to use with HQplayer in PCM. 

Thank you 

 

 

This is indeed an intersting question.

 

First: the facts:

The DAC200 uses 4 PCM1795 converter chips for converting PCM signals to analog. The PCM1795 consists of a 8x oversampling filter followed by a ΣΔ DAC.

In case of the T+A devices the 8x oversampling inside the PCM1795 is completely bypassed and the digital signal is directly fed to the ΣΔ  modulator.

If one of the DAC200's PCM oversampling filters (FIR1, FIR2, Bezier1, Bezier2) is selected, the oversampling is done in an external DSP (using T+A's own oversampling algorithms) , the internal filters of the PCM1795 are never used.

 

If the oversampling is switched OFF and NOS1 or NOS2 mode is selected, the external DSP is also bypassed and the incoming PCM stream is directly routed to the ΣΔ  modulator stage of the DACs without any signal processing before the modulator stage.

 

So, as a first result we can state that in the DAC200 all PCM oversampling filters are bypassed in case of NOS mode.

 

The question now is: does the ΣΔ  modulator stage perform oversampling or not ?

 

This question is a bit philosophical and the answer depends on weather you regard the output signal of the ΣΔ  modulator as a highly oversampled 1 bit digital signal (in this case it performs a kind of oversampling), or if you regard the modulators output signal as an analog signal having an average value representing the analog output value - in this case the modulator is DAC delivering an analog output voltage which only needs some averaging (analog low-pass filtering) to get rid of the unwanted high frequency noise and to deliver the wanted analog signal average.

 

Some more details about this topic are given in this paper: https://www.beis.de/Elektronik/DeltaSigma/DeltaSigma.html

 

 

More than this consideration it might be interesting to look at the output signal of the DAC200 and find out if it behaves as would be expected from a NOS DAC.

 

 

1.) Outut signal from the I/V stage in NOS2 mode when the DAC200 is fed with a digital step signal @fs=44.1 kHz (blue trace):

 

 

 

The output signal after the I/V stage of the DAC. It rises instantly at the digital signal step, without any trace of interpolation. A NOS R2R converter would behave exactly the same way.

 

Please note: This signal is the signal before the final analog reconstruction filter. It is an internal signal and can not be measured at the output jacks of the DAC200.

 

----------------------------------------------------------------------------------------------------------

 

2.) The same signal after the analog reconstruction filter, as it appears at the DAC200 output:

 

 

The output signal after the analog output filter slews a bit slower than the signal in the first measurement. This slower slew corersponds to the 120 kHz cut-off frequency of the DAC200's analog output filter (in "WIDE" mode) - it is NOT a consequence of digital interpolation.

 

----------------------------------------------------------------------------------------------------------

 

For comparison:

This is the DAC200 output signal with the same digital step input signal with oversampling filter "FIR1":

 

 

 

This output waveform shows the much slower response due to the interpolation performed by the digital FIR oversampling filter.

 

 

 

The presented step measurements clearly show the Non Oversampling behaviour of the DAC200.

The output is exactly what would be expected from a NOS DAC and the presented output signals are indistinguishable from the output signals of a NOS  R2R DAC fed with the same digital input signal.

 

Imho the DAC200 is very well suited to operate with high quality external oversamplers such as HQ player, because inside of the DAC200 no oversampling/interpolation takes place and the quality of the externally oversampled signal is preserved in all detail.

 

 

[OE333]

Just now, Nkam said:

I just don’t know why, but every op amp analog output DAC I’ve tried doesn’t sound as good as discreet.  
why is that?
 

https://audiophilestyle.com/forums/topic/67752-someone-please-explain-is-a-discreet-analog-output-stage-better-or-op-amps/

 

To say it with the words of  Ludwig Mies van der Rohe: Less is More

 

or

 

in an integrated OP-Amp there is no choice - all components have to made from silicon. In a discrete amplifier the designer can choose the best possible type of component for each part of his circuit He can also tailor the circuit exactly to the specific needs and requirements of the device he is designing.

Very often this results in less complex circuits with fewer but higher quality parts and less chances for errors and imperfections.

So in many cases an experienced analog designer can tweak a discrete circuit to higher performance levels than a universal-to-use  off-the-shelf integrated standard part can deliver.

[OE333]

10 hours ago, Nkam said:

what do you say to them? 

 

Listen !   😉

[OE333]

4 hours ago, Nkam said:

Why did you choose that much older DAC chip over the newer ones?  
Don’t the newer ones offer any advantages in technology for a ‘ better sound’?

 

We have a long experience with the PCM1795 knowing how to make best use of it (including completely a discrete I/V stage). The converter stage of the PCM1995 is a very good design - and that's all we use from this chip. The rest (oversampling/filtering etc.) is completely bypassed.

 

 

 

4 hours ago, Nkam said:

ah also.  Does the older model DAC8 have the same exact PCM architecture as the 200 and same analog output stage?

 

 

The PCM circuit design of DAC8DSD and DAC200 is similar but not identical.

For example the DAC200 uses newer clock circuits having much lower jitter. Furthermore a new DSP and new improved upsampling algorithms are used.

 

The analog stages are completely different. DAC200 uses fully discrete analog circuits derived from the T+A "HV" series.

An other big difference is the analog volume control. In DAC8DSD the volume control used integrated circuits, in DAC200 the volume control is by hermetically sealed gold-contact relays and audiophile high precision resistors.

 

[OE333]

On 4/11/2023 at 7:47 AM, Nkam said:

Does the DAC 200 have extra headroom for intersample overs? 
To avoid clipping internally ?

 

Yes. There is no clipping no matter of which upsampling method used.

[OE333]

2 hours ago, Nkam said:

Any measurements of the T+A?

 

... anything special you are interested in ?

 

[OE333]

4 hours ago, Nkam said:

any FFT to show which harmonics are dominant?

 

... no problem: I will post a few FFTs when I'm back in office.

[OE333]

On 4/12/2023 at 5:15 PM, pavi said:

 

does the t+a dac200 perform equally well at dsd512 & dsd1024? 
 

 

Miska has already brilliantly answered your questions - I personally use DSD512.

DSD1024 would give a still better out-of-band noise performance but at the price of a very high work-load on the HQP server...

[OE333]

On 4/12/2023 at 11:01 AM, Nkam said:

... any FFT to show which harmonics are dominant?

I saw the specs and the THD is low enough.  
just which harmonics are there.  
 

thanks in advance! 

 

Here some FFT measurements showing the harmonics of the DAC200 at the RCA and XLR outputs.

 

The PCM measurement was taken with a 192/24 bit input stream, the DSD measurement with a DSD256 stream.

The harmonics do not change significantly with the data rate, just the out-of-band noise decreases with increasing sample rate.

 

The absolute THD value for PCM is 0.0015%, and for DSD it is 0.0006%.

 

Measurement1:  THD for PCM 192/24

 

 

 

 

 

Measurement 2:  THD for DSD256

 

 

 

 

 

And here a measurement of the in-band noise floor: