PRODUCTS   HOW TO ORDER   FAQs   COMPANY   PRESS & REVIEWS   DOWNLOADS   CONTACTS   HOME
 

 
FAQs


2015 cheap best swiss rolex,audemars piguet,panerai,iwc,hublot,tag heuer,breitling,patek philippe,omega replica watches,omega Constellation watches,omega DeVille watches,omega Seamaster replica,fake watches for sale,top quality bvlgari,cartier,chopard,corum,franck muller,longines,buy replica watches,tissot,u-boat,ulysse nardin,versace,glashutte,graham jaeger cheap replica watcheslecoutre etc.
 

Which audio formats can be archived
How do I operate the Ti48 CD/HD Transport / Mercury CD/HD Player
What does the Ti48/Mercury digital audio processing software do



Which audio formats can be archived and replayed


1) Can I archive MP3 or other compressed music files ?
The Ti48 was designed to archive only CD quality data (16 bits / 44.1kHz) and then to replay this with upsampling in order to extract the most out of the CD audio format.

2) Can I record from the internet ?
Not directly into the Ti48, which does not have a modem built-in.

3) Can I archive from analogue sources e.g. LP or tuner?
The software upgrade mentioned in (3) will also allow the recording of an analogue signal into the Ti48 using a suitable analogue-to-digital converter .

4) Can I playback SACD ? What about 24/96 or 24/192 PCM discs from the audiophile labels ?
The Ti48 will play back and archive the Red Book CD layer of a SACD. The Ti48 cannot play SACDs due to the hardware configuration mandated by the SACD license (no PC-based device can playback SACDs). Some 24/96 or 24/192 recordings can be played and archived by the Ti48. As audiophile record labels are always offering new types of high-rez recordings, please check with us for compatibility with the Ti48.




How do I operate the Ti48 archiving transport and Ar38 DAC


6) Do I need a monitor or TV plus keyboard to use the Ti48 ?
The Ti48 was designed as an audio-only source. Therefore it is operated using just the supplied remote control and the built-in screen as the user interfaces. A separate computer monitor or TV are not required.

7) Can I plug in a monitor and keyboard to manage my music files ?
Not at the moment though it may be a possibility should enough customers request it. The remote control and built-in screen allow a great deal of hard-disk file management.

8) How do I enter the album and artist names of the CDs that I archive ?
With most mainstream and audiophile music releases, the CDs will be recognised by the Ti48's database and the artist and album names and track titles will be automatically saved when a CD is archived. When a CD is not recognised, text entry can be made in the same way as with a mobile phone, using the alphanumeric keys on the remote control.

9) How does the Ti48 recognise CDs ?
Pre-loaded into the hard-disk drives is a compressed version of the FreeDB database called EmDB. This database, which is constantly being expanded, currently contains the album titles, artists names and track titles of over 2,000,000 CDs submitted and catalogued by the members of the public . You can read about FreeDB here : www.freedb.net

10) How can the CD recognition database be updated ?
A CD-ROM will be available on a quarterly basis from Zero One Audio that will contain the latest updated FreeDB database in a compressed format. This CD-ROM will be self-booting, so the Ti48 will be able to update itself using the disc. In the near future, this website will have a page that will allow the download of the compressed database from Zero One Audio's server into your computer. From your computer, you can then burn your own CD-ROM and load the database into the Ti48.

11) Can I use my own DAC with the Ti48 ?
Yes. The Ti48 also has an S/PDIF digital output. The data sampling rate will be limited to 24 bits/96kHz via S/PDIF as this is the limit of the S/PDIF standard (whereas the Zero One Audio I2S data transfer allows a sampling rate of up to 24 bits/192kHz to be sent to the Ar38).

In order to further improve the performance of a DAC connected by S/PDIF, the Ti48 has 3 user-selectable dither options (see 19 below).

12) Can I use my own transport with the Ar38 ?
Yes. The Ar38 has a digital (S/PDIF) input. The Ar38 can accept digital audio data from any compliant source up to 24 bits/96kHz. It will upsample all acceptable digital audio data to 24 bits/96kHz using its own sampling rate converter.

13) Can I plug another digital source into the Ar38 ?
Yes. See (12) above. This means you can also feed the (stereo only) digital output from a DAB radio or DVD player to the Ar38. The Ti48 can be plugged into the Ar38 using the I2S link at the same time. A switch on the back panel of the Ar38 selects either I2S or S/PDIF input

14) Can I increase the hard-disk capacity of the Ti48 myself ?
The hard-disks are encoded and therefore, they cannot be replaced by off-the-shelf hard-disk drives. WE can supply




What does the Ti48 digital audio processing software do


15) What is upsampling ?
Upsampling and oversampling are forms of sample rate conversion (SRC), where one sampling rate (like the 44.1kHz of CD) is converted to another. With oversampling, the source rate is stretched out to an integer multiple (eg. 4 times to 176.4kHz) by mathematical interpolation. The term upsampling tends to be used when conversion of the audio data is to a non-integer multiple of the source rate (eg. 96kHz). SRC produces more output than input bits, so devices such as the Ti48 increase the bit depth of the data to improve the accuracy of the processing and output.

Neither upsampling nor oversampling adds data that did not already exist on the CD being played back. The benefits of the process mainly result from pushing the digital images that arise as part of all digital sampling processes further away from the audio band. With a sampling frequency of 44.1kHz, digital images of the data would appear directly after the valid audio data (at 22.05kHz). A very steep filter (commonly referred to as a "brick wall") would be required to remove the ultrasonic mirror images perfectly, but the ringing that such filters introduce may affect the sound quality.

By upsampling to for example, 176.4kHz, the digital images of the data would be pushed out beyond 88.2kHz allowing the use of a digital filter with a gentler slope to reduce the ringing and phase changes.

Another possible benefit of having less steep digital filters is that these filters allow some ultrasonic noise to reach the D-to-A conversion chips. The ultrasonic noise may be acting as dither which would help to optimise the performance of the chips.

The Ti48 has a choice of three digital filters ( "upsampling modes") powered by a 2GHz processor. Our custom software computes the audio data with 64-bit double-precision floating point arithmetic for high level accuracy. . Because the Ti48 is not based around a fixed piece of silicon, the digital filters can be upgraded at a later date to offer higher performance as the technology advances.

16) When setting the Ti48, which upsampling frequency should I use
There is no one setting that will suit all preferences, hence the selection available. When paired with the Ar38 via I2S, we would recommend setting the upsampling frequency to 176.4kHz. When paired with a DAC using S/PDIF, it is worthwhile trying a higher sampling frequency, up to a maximum of 96kHz, if your DAC is capable of accepting higher sampling rates. In our tests, we found that 88.2kHz improved the performance of some DACs compared to using standard 44.1kHz.

17) When setting the Ti48, which upsampling mode should I use
The upsampling modes refer to the various user-selectable digital filters available in the Ti48 menu. Digital filters are a standard part of modern digital audio design but the way they are implemented can have a significant effect on the quality of audio reproduction. The four modes : Purist, HQ1, HQ2, HQ3 indicate increasingly more complex, steeper digital filters.

In general, the Purist mode offers better low level ambience, transparency and musicality whilst at the other extreme, HQ3 mode might be more suited to rock music. The actual effect will depend a great deal on the rest of your playback system. We recommend that you run-in the Ti48 using HQ2 and then experiment with the other settings using a number of different styles of music.

18) Which wordlength should I use
The dither wordlength should ideally be set to the maximum wordlength which the DAC can receive and use. In the case of the Ar38, it can be left at 24-bit. If you use a standard 16-bit DAC, the wordlength should be set to 16-bit.

19) Which dither type should I use
Dither is the addition of digital noise to the audio signal in order to improve the linearity and low level resolution of the system. For the technically inclined, the three dither options available in the Ti48 are :
TPDF - traditional triangular distribution dither
Nyquist - high frequency noise at the end of the spectrum
NShape - second order noise shaping tilted toward the high frequencies

The different dither types can be used to tailor the sound and to improve the performance of a DAC when using the S/PDIF connection. We would recommend running in the Ti48 without any dither set and then experimenting with the different dither types till you find a preferred one.
 


Copyright © 2002-2004 www.zerooneaudio.com. All rights reserved.