[slim.a]

Quote:

Originally Posted by Omega17TheTrue /img/forum/go_quote.gif I ordered this converter but i have a stupid question : If the converter and my DAC are on 24/96 and if i play a 16/44.1 song (like 99% of my music) does it apply any kind of upsampling or oversampling ? or does it just play 16/44 without modifications ?

Quote:

Originally Posted by Fujak /img/forum/go_quote.gif Hi Omega17TheTrue, your question is not as stupid as you think: The DAC switches - in most cases/modells automatically - to the correct samplerate/bitrate depending on the samplerate/bitrate of the receiving signal. The same does TeraLink X2. So no need to worry about. However: if there is a switch at your DAC to change samplerate manually and this is switched to 96/24 while your signal is 44.1/16 then it will be upsampled by the DAC to the switched target rate (in this case 96/24) - so in this case it would be better to adapt manually the samplerate to receiving signal in order to avoid loss. I hope this answered your question. All the best Fujak

In the case of the Compass that Omega17TheTrue seems to be using, there is no sample rate change (ie no upconvert nor downcovert).

If you play 16/44 with a bit perfect player, then the DAC will receive 16/44 and will send exactly that to the AD1852 dac chip. (Of course, the AD1852 uses internally oversampling but that is another story).

The same rule apply for 16/48, 24/48, 24/88, 24/96, ...

Having a converter that is capable of 24/192 does not mean that data is processed at 24/192 all the time. It just means that the converter accepts data up to 24/192.

In order for a DAC to upsample by itself you need to install a Sample Rate Converter inside. If there is no SRC inside of the DAC, it will treat whatever bit rate without upsampling or downsampling.

 

[Omega17TheTrue]

Thanks for the answers, so the AD1852 chip internaly already upsample my signal ? Well it does not really matter, i will hear what methods sound best.

Also another question, the teralink have a RJ45 IS2 output but it need a modification of the DAC to be compatible that why there is a diagram on the teralink it is reserved to great DIYer and need a IS2 compatible chip, right ?

Maybe kingwa can make a IS2 input compatible with the teralink.

Theoretically IS2 is better than SPDIF ?

 

[slim.a]

Quote:

Originally Posted by Omega17TheTrue /img/forum/go_quote.gif Thanks for the answers, so the AD1852 chip internaly already upsample my signal ? Well it does not really matter, i will hear what methods sound best.

As I said, the AD1852 does not upsample.

However, as most modern dac chips, the AD1852 uses oversampling in its digital filter. Oversampling is different from the upsampling. If you have the technical knowledge and curiosity you can look at the data sheet here : http://www.analog.com/static/importe...ets/AD1852.pdf).

If you want to upsample data to 24/96 once you get the Teralink-X2 there are a lot of media players that come with upsampling plugins (Foobar, MediaMonkey, cPlay, ...)

But since this is off topic, I will stop here.

 

[Omega17TheTrue]

oh yes i misread oversampling and upsampling it is indeed a different thing, thank for the link that a good reading.

 

[Ciu]

Hello !


Does anyone has experience with Teralink-X2, using a DAC Sabre 9008 ?

The previous version of Teralink was not working (cycling hiss : Terralink-X> Buf24 SPDIF trouble - Buffalo DAC - Twisted Pear Audio Support) with Twisted Pear Audio Sabre DAc, I have asked help from TPA and Teralink Seller, but no one provided any help to this problem !

R.C.

 

[thoppa]

Hi,

I can't help you either - sorry - but I think it's shameful that neither seller will help either. Can you return either for a refund ? I'm very surprised Teradak won't help - they've been very good to me. What did they say ?

cheers,

Tom

 

[Ciu]

This the response from Vintage Audio Lab :
Quote:

Dear Sir: I think it is problem in data format. Your teralink may set to 48k mode and ess dac may not able to decode 48k spdif data. Sincerely, Kevin

I thought it was a joke !!!

I asked :
Quote:

Why do you say "Teralink may set to 48k" ?

Since December 6th, no more message.... inefficient ??? impolite fellow ???

R.C.

 

[thoppa]

Hi,

Well, I must admit I was not at all impressed with Kevin either. It's a shame he's the main seller on Ebay really.

Try contacting Teradak directly. TeraDak Audio Electric Company

I'm sure they'll be much more helpful.

 

[Fujak]

Quote:

Originally Posted by Ciu /img/forum/go_quote.gif This the response from Vintage Audio Lab : I thought it was a joke !!! I asked : Since December 6th, no more message.... inefficient ??? impolite fellow ??? R.C.

Hi,

I just want to tell you, that I have had a similiar experience with Kevin / Vintage Audio Lab. 8 weeks ago I ordered a DAC (Valab 4395 Platinum) via Ebay.com. When the DAC arrived I have to notice, thatt the front glass was broken (probably during shipping). I informed Kevin and offerd him that he just could send a new front glass in order to change it by my self (and of course to avoid further costs for him by sending back and shipping again to me). He begged my pardon and promised me to send a new front glass to me immediately. But I didn't received any front glass til today, and to e-mails, which I sent to him remain without any reaction. So maybe it's time to inform Ebay about that.

Fujak

 

[thoppa]

Hi,

I finished a sigma11 today set for 5V. I connected it into the usb power by cutting a cable. It is much better that the onboard regulator and usb power but only gives a little bit more definition.

I looked up the datasheet for the LT1084 - it seems it has .003% noise for the output voltage, so in this case the noise is 150uV. The sigma11 is around 15uV and I'm pleased to say this makes a difference, although again, it isn't huge. I think it only helps the tcxo, which is why it doesn't make that much difference to the sq.

The onboard 3.3V regulator is an AMS1117 3.3V in sot-223. It also has 0.003%, which is 100uV of noise for a 3.3v output and it seems this is typical for sot223.

So without major surgery, the performance is pretty much fixed at its present level.

cheers

 

[teraguy]

If you have driver issuew either in XP/Win7 OS, you can mail the error messages to the Teradak Michael. He will forward the error messages to the vendor and help you solve the software problem. He should ask the vendor driver engineers to solve the problems if the error messages are very clear and can be reproduced. We hopes the final driver can be robust as well as possible.
Everyone's PC is very different and the environments are also very different. Therefore, the drivers may be modified very often and should take some time to converge.

It is very difficult to solve the bugs without clear error messages. Any released driver is tested OK in the driver engineers's desktop PC. Their testing procedures may not cover all of the real conditions. It then may not be the expected result for some users. Therefore, we should feedback the error messages to the driver engineers if we have the software issues. Otherwise, they always thought their dirvers are OK. It is believed the driver will be very robust finally.

 

[teraguy]

If you have problems, you can mail the Teradak for your experiences. They will help you if they understand how to solve them. They may not have your great DAC experiences. Sometimes it may be difficult to give you the correct suggestion.

They have used their Teradak-X in their previous TDA1543 DAC. It implied the I2S from the TeraDak-X is OK. For the TeraDak-X2, they also used it in their newest Chameleon DAC. It is also no problem for the I2S output.




Quote:

Originally Posted by Ciu /img/forum/go_quote.gif This the response from Vintage Audio Lab : I thought it was a joke !!! I asked : Since December 6th, no more message.... inefficient ??? impolite fellow ??? R.C.

 

[Omega17TheTrue]

I still wait my teradak from vintage audio since the 9 mars ...

I hope it will come soon.

 

[thoppa]

Two weeks is about right - you should get it any day now....

I think I've found an upgrade for the 3.3V reg. It has similar specs but much lower noise; just 40uV noise as opposed to 100uV. Of course, they could have been measured differently.....

The DCY package is sot-223 4-pin but they have different pin connections to the AMS1117. The ams is ground-out-in and tab is in, and the Ti is in-ground-out and the tab is gnd.

Linear Regulators - Single Channel LDO - TL1963A-33 - TI.com

Here I removed the ams regulator. The heatsink pad is not connected to anything so the TL1963 will work.

Here I removed the LT regulator and associated components so I will feed an external regulated 5V into the X2 instead of the 8-12V. I shorted it (pin 3 in and pin 2 out) through a ferrite bead for more noise reduction. The heatsink pad is the connection ffrom pin 2 to the power selector switch.

I'll update this post when the modification is complete.

 

[thoppa]

Quote:

Originally Posted by teraguy /img/forum/go_quote.gif It is believed the driver will be very robust finally.

Where can people download it ? Please post a link.

I think if you are serious about getting 'beta-feedback' to make the driver as good as it can be, then you (or whomever) needs to make it publicly available right ?

I think the X2 should have a slight re-design.

1) The regulation isn't as good as it can be. If the board is redesigned to accept smt regulators, then it could use the Texas Instruments REG113 and TPS793XX regulators.

2) Install a socket for the 12Mhz tcxo so users can try different xo's to find the best one.

Just my ideas. I think it's a great device and I'm very pleased with it.