AVGURU, please see my answers below,
Denon uses their famed ALU processing (an arithmetic logarithm) to "interpolate" a word length of 24 bits from a standard 16 bit redbook cd. They've been using this technology for the last 10 years in everything from their recievers to their dvd players to their cd players.
>>> Denon has refined their algorithm for the 24 bit expansion. There are many other companies using similar techniques. Philips SACD1000 and even the little Pioneer 563a are also expanding to 24 bit. Of course, the engine incorporated to do the job is really important. In the Denon 3910 case, as I mentioned earlier, this is done by Worlds best hands down Analog Devices SHARC Audio DSP.
This is a proprietary process that Denon has developed. Other more "hi-fi" companies such as Ayre, Cary, Arcam etc accomplish the same feat through a different process that I'm not technical enough to explain. But the results speak for themselves and I don't think most people reading this post feel that Denon's sound is anywhere close to the performance levels of the companies mentioned above. And to be honest, there are great 1 bit cd players on the market today that sound incredibly good. So I'm not even sure if interpolating data to a larger bit stream is critical to obtaining great sound.
>>> See the above answer. The Bitstream conversion has nothing to do with the bit rate expansion.
Regarding upsampling (atually there's no such thing and it should be referred to as oversampling)your comment "there's no theoretical or practical advantadge to upsampling the cd" is not true. While Denon may have come to this decision after reviewing the overall design and performance criteria of their units, there are many other companies (including Marantz which is now owned by Denon) that are very high on the concept and use it with regularity. Ayre, Arcam, Cary, Musical Fidelity, Esoteric, etc are but a few of the companies that routinely use oversampling in their cd players and with GREAT RESULTS! All of the above companies are much more highly respected than Denon when it comes to their engineering design and "know how".
>>> Oversampling and Upsampling (actually Re-sampling) are two different things. It does not matter to me what the other companies do with GREAT RESULTS because whatever they do does not sound right. The Re-sampling to any rate does not improve the quality of a CD. This can be clearly seen in a Spectral Analysis after Re-sampling which I have done using the best CD/DVD mastering program available in the World. It is also clearly stated in their instruction manual that re-sampling the CD will NOT improve the audio quality. Further more, when CD is re-sampled to 96 KHz or 192 KHz there is actual loss of information because these frequencies do not divide by 44.1KHZ but to 48 KHz. So mathematical truncation is used for the conversion. Re-sampling to 96 or 192 makes it actually worse than just keeping it as 44.1 but is really good marketing bringing a lot of money.
I agree that oversampling is not always necessary to achieve good sounding cd playback. But I just want to make it clear to everyone reading your comments that was a decision Denon made and reasons could be varied...anywhere from cost concerns to the design of their unit not being compatible with oversampling. You will note that on Esoterics's UX1 player they decided not provide all of the oversampling options available on the DV 50. One of the primary reasons for this was the design of their transport made it unnecessary to do so.
>>> That was a wise decision for Teac. Again, oversampling is something different that happens in the Digital Filter for PCM and uses LINEAR interpolation. The transport has nothing to do with that.
Regarding the DV-50's transport being the same as the Pioneers, please do not understate the importance/impact of adding the clamping mechanism...which reduces jitter and allows the laser mechanism to track the disc in a more linear and accurate fashion. In my mind this modification alone puts the Esoteric transport on a higher level above the Pioneer. Furthermore, the laser tracking mechanism and the laser wavelengths (which are adjustable) help by determining how far the player is capable of digging in to the "cd pits" and obtaining the recorded information.
>>> The clamper is nicer, I agree, but this is not necessarily removing the jitter from the transport. Also the clamper has nothing to do with the Laser tracking. The Laser tracking mechanism and laser wavelengths (which can not be adjustable) remain untouched and original to the Pioneer transport found in the DV-50.
As you know, many laser tracking mechanisms travel on a thin wire that in itself is subject to vibration. The better companies such as Esoteric do not use this method..or they use a better version. In my mind the outer housing,laser mechansim, etc are all part of the transport and in this regard the Esoteric does have a better transport than the Denon. You are free to disagree as I'm sure you will.
>>> There is no Laser mechanism that travels on thin wires. If you are referring to the actual top lens of the Laser pick up then yes it is suspended in thin wires in 99% of the cases including DV-50. The ONLY laser pick up in the World to date using pure magnetic field for the top lens suspension in the Laser pick up and radial primary tracking is Philips. As I mentioned above, the Laser tracking mechanism in the DV-50 is not upgraded in any way from its original Pioneer state.
Regarding comparing the DSP (Digital Surround processing)chips in both units that really doesn't concern me as I'm much more interested in analog audio performance (op amps, DAC's and their associated filtering processes) than I am with digital processing..most of which is associated with video and digital processing speed. Is the Denon the better DVD player? Probably.
Do I care? NO!
Is HDCD a nice feature to have? Maybe to some but not to me since the in my listening tests the use of the three oversampling filters can bring a level of resolution to cd's that's better than HDCD.
>>> DSP stands for Digital Signal Processing and I was referring strictly to the AUDIO DSP in the Denon which, again, is superior to the one in DV-50. As for the HDCD decoding, you really need to hear how HDCD sounds with the Denon 3910 compared to other HDCD or non HDCD machines. The Analog Devices DSP is practically unbeatable.
Alex, 711 has given me several extended listening auditions of your units and I think they sound incredible..much better than the DV 50 in terms of musicality. And if you are successful in bringing the DV 50 to a level of performance on par with your APL 3910 I will gladly be one of your next customers requesting an upgrade. But I just had to respond to your comments and imho the build quality, transport and overall engineering found in the DV 50 is on a much higher level than the 3910. To be able to use the lesser Denon platform and take it to a level of performance that surpasses the DV 50 is high praise indeed and a testament to your modding skills!
>>> I am glad that you liked my 3910. It is actually not modded, it is my own machine. All I use from it is its transport and DSP just like many other companies like Krell, Musical Fidelity (Philips). Marantz (Philips, Sony, Pioneer). Teac (Pioneer), etc. The digital information from the transport is taken to my own DAC board then to my own tubed Analog stage which are powered by my own power supply.
The only better thing about DV-50 compared the Denon is its much nicer enclosure, nothing else. Of course, the DV-50 DACs, Analog stage and Power supply might be and I am sure are much better than the Denon, but I do not have any reasons to care about that because I completely bypass and disable them with my re-design. Since ALL I care is the transport and DSP of a given machine, the Denon 3910 makes better platform than the DV-50 at least theoretically. I do have DV-50 coming in for evaluation so the results will be announced soon.
Now, if you ask me which machine in current production features the best transport, I will say it is Teac VRDS in the UX-1 and X-01. There is nothing better currently available. I can not comment on their DSP though. It would be nice to use one of these for a platform but their price tag is really high. Who knows, I might be able to do it some day.
Regards,
Alex
