Sennheiser HDVD800 Headphone Amplifier
Jun 11, 2013 at 9:32 PM Post #901 of 3,016
Quote:
from whatI am gathering there is 2 amplifiers. One for each channel sort of like mono blocks all in one chassis. That is the way a true balanced amplifier would work. One amplifier for each channel.  This is supposed to be a fully balanced design.  The amp does indeed sound good.

 
Actually, I'm pretty sure that there are 4 amplifiers, 2 for each channel. For one channel in a balanced system, a pair of amplifiers work together in split phase. During the positive going phase of the signal, the first amp drives the + line positive while the other amp drives the - line negative. During the negative going phase of the signal, the first amp drives the + line negative while the other amp drives the - line positive. This is how a balanced configuration can double the slew rate of a single ended one since the + and - lines are moving away or toward each other twice as fast than if one were anchored to ground (single ended). This is why some mono-block amplifiers on the market can be reconfigured to run in a standard stereo mode by separating the two internal amplifiers into independently operating single ended amps.
 
Again, I'd like to see some schematics of this thing.
 
- Jeff
 
Jun 11, 2013 at 9:38 PM Post #902 of 3,016
Quote:
 
Actually, I'm pretty sure that there are 4 amplifiers, 2 for each channel. For one channel in a balanced system, a pair of amplifiers work together in split phase. During the positive going phase of the signal, the first amp drives the + line positive while the other amp drives the - line negative. During the negative going phase of the signal, the first amp drives the + line negative while the other amp drives the - line positive. This is how a balanced configuration can double the slew rate of a single ended one since the + and - lines are moving away or toward each other twice as fast than if one were anchored to ground (single ended). This is why some mono-block amplifiers on the market can be reconfigured to run in a standard stereo mode by separating the two internal amplifiers into independently operating single ended amps.
 
Again, I'd like to see some schematics of this thing.
 
- Jeff

Jeff I doubt you can get the schematic. They are saying nothing about the design other than what they published on the website and in the video. I have been pulling teeth to get some information for my review and Sennheiser USA is not getting the answers I need to include everything in the review. I also get no response from the Sennheiser guys here at headfi. I tried but whatever reason they are being evasive, but I will write this review and send it to them for a fact check and then have it published.  It sounds great. I think they would sell more of them if everyone knew what was in the design.   
 
Jun 11, 2013 at 10:31 PM Post #903 of 3,016
Ok, so all of the current advertising literature for the HDVD800's sample rate capabilities that I can find appears to be WRONG (including a couple of notes and brochures I found on Sennheiser's own website)
 
They all basically say the same thing: "All of the digital inputs (i.e., S/PDIF Optical, S/PDIF Coax, AES/BEU, and USB) can handle all of the same sampling rates (i.e., 44.1, 48, 88.2, 96, 176.4, and 192 KHz)"
 
This was one of the reasons I bought the HDVD800 was for flexibility of interfaces and the ability to extend it a ways from my computer if necessary.
 
Well, in the Instruction Manual files that came with the HDVD800, there is a single note in the specification section stating that the S/PDIF Optical has a Maximum rate of 88.2 KHz. It cannot handle 96, 176.4, or 192 KHz sample rates.
 
Hmmm. So I pull out my 2 meter Monoprice.com TOSlink cable (remember, the HDVD800 manual says that I can use up to 5 meters), plug it into my iMac (no adapters here) and the HDVD800, and guess what? Sure enough, at 24/96 KHz the audio stream starts glitching continuously every few seconds! Sometimes multiple times a second, sometimes maybe 10-30 seconds between dropouts. These are very brief, "clicking" like sounds each time.
 
So I set my sample rate to 24/88.2 KHz and...no more glitches/clicking. All lower rates, no problems. Just like the Instruction Manual SAYS it should!
 
Vent on:
I have a real problem with false advertising, especially when it is coming from the actual manufacturer of a given product. You will have a tough time convincing me that the "fine German engineering" referred to in all of the advertising literature and videos for this product somehow didn't get around to fully testing the optical interface. Someone knew enough to put the caveat in the Instruction manual, but didn't put it into any of the rollout advertising.
Vent off:
 
Ok, I feel MUCH better now!
redface.gif

 
On a definitely more POSITIVE note, while glitching over the optical was occurring, I tried comparing the actual sound quality with what I was also getting over the USB interface of the same audio track and speed. I could NOT reliably identify any difference in the audio quality between the solid USB input and the glitching optical input. I could not readily hear any artifacts that might be contributed to jitter. The clock recovery mechanism for the S/PDIF optical section must really be pretty good.
 
This was a real surprise to me (and a pleasant one at that). In my limited experience, as you approach the limitations of a digital interface, you frequently start seeing audio artifacts associated with increases in jitter. I'm still in the burn in mode (80-90 hours) so not sure if this will change much over time.
 
- Jeff
 
Jun 11, 2013 at 10:58 PM Post #904 of 3,016
Jeff I noticed differences for the better after 100 hrs and up to about 150 hrs . I like the dac actually quite a bit. I will be putting all the details in my review which i hope to have finished by next week and up the following week in Dagogo
 
Jun 12, 2013 at 12:57 PM Post #906 of 3,016
Just got my HDVD800 (It does come with a power cable btw, its hidden in the cardboard packaging)
 
I am literally speechless right now. I have never heard something so good over USB in my entire life.
basshead.gif

 
Jun 12, 2013 at 7:55 PM Post #907 of 3,016
Hey guys, so I got the chance to listen to this amp last week on a pair of HD800s at a store and the details of the music just blew me away! 
gs1000.gif
 One thing that caught my attention and made my jaw drop to the floor was the detail it gave to string instruments and how natural the sound was. I listened to a song with a cello (at least I think it was a cello) and I could hear the way the bow was being pulled across the strings and it almost felt like I was right there watching the cellist masterfully play the song.
 
With that said, I am also curious how it compares to a Burson Soloist or even the Soloist SL since the store I went to was not a dealer for Burson. How are the details of the Burson amps compared to the HDVD 800? How is the soundstage and the ambiance between the two amps? Was that detail a result of the amp or is that amount of detail able to be produced on just about any amplifier with the HD800s?
 
Jun 12, 2013 at 8:37 PM Post #908 of 3,016
I have been waiting for my Cardas Clear XLR 4 pin balanced cable for my HD800s & HDVD 800 combo for over a month from my dealer in Toronto but the lads at Cardas made an error and end up sending my dealer the Cardas Clear Light XLR 4 pin balanced cable.
I have been researching on the internet for reviews for the Cardas Clear Light headphone cables for the HD800 with absolutely no luck.
My dealer suggested that I'd be better off getting the Cardas "Clear Light" XLR 4 pin Cable and the Cardas Quadlink Power cable for the same price as the Cardas "Clear" Headphone cable and that it actually will improve the quality of the sound more.
Any suggestions would be greatly appreciated.
 
Thanks gentleman.
 
Jun 12, 2013 at 8:45 PM Post #909 of 3,016
Quote:
I have been waiting for my Cardas Clear XLR 4 pin balanced cable for my HD800s & HDVD 800 combo for over a month from my dealer in Toronto but the lads at Cardas made an error and end up sending my dealer the Cardas Clear Light XLR 4 pin balanced cable.
I have been researching on the internet for reviews for the Cardas Clear Light headphone cables for the HD800 with absolutely no luck.
My dealer suggested that I'd be better off getting the Cardas "Clear Light" XLR 4 pin Cable and the Cardas Quadlink Power cable for the same price as the Cardas "Clear" Headphone cable and that it actually will improve the quality of the sound more.
Any suggestions would be greatly appreciated.
 
Thanks gentleman.

 
rolleyes.gif

 
Jun 12, 2013 at 9:39 PM Post #910 of 3,016
Quote:
I have been waiting for my Cardas Clear XLR 4 pin balanced cable for my HD800s & HDVD 800 combo for over a month from my dealer in Toronto but the lads at Cardas made an error and end up sending my dealer the Cardas Clear Light XLR 4 pin balanced cable.
I have been researching on the internet for reviews for the Cardas Clear Light headphone cables for the HD800 with absolutely no luck.
My dealer suggested that I'd be better off getting the Cardas "Clear Light" XLR 4 pin Cable and the Cardas Quadlink Power cable for the same price as the Cardas "Clear" Headphone cable and that it actually will improve the quality of the sound more.
Any suggestions would be greatly appreciated.
 
Thanks gentleman.

personally i can notice SQ differences between stock and good aftermarket cables but when i tried more expensive higher end cables i couldnt hear any further improvement at all. So for me I would tend to take the power cable and HP cable option as then you will have both bases covered. 
 
With saying that however the only real way of knowing is by having both cardas cables to see if you can hear any improvement yourself - which is probably not possible unless you purchase both and then return one
 
Jun 12, 2013 at 11:14 PM Post #911 of 3,016
Quote:
Just got my HDVD800 (It does come with a power cable btw, its hidden in the cardboard packaging)
 
I am literally speechless right now. I have never heard something so good over USB in my entire life.
basshead.gif

 
I have to say that the USB audio implementation sounds superb, at least to my ears and with my current set-up:
 
MacBook Pro 15 Retina > Pure Music > WireWorld Ultraviolet USB Cable > HDVD800 > HD800
 
Jun 12, 2013 at 11:43 PM Post #912 of 3,016
Quote:
The DAC section is excellent one of the best neutral and musical and gives every bit of information.

I agree. It sounds great. I am liking it more than the Rega DAC and that is saying much. The Rega DAC is an excellent partner to my Rega Apollo-R CD Player/Transport.
 
Jun 13, 2013 at 12:59 AM Post #913 of 3,016
I have been waiting for my Cardas Clear XLR 4 pin balanced cable for my HD800s & HDVD 800 combo for over a month from my dealer in Toronto but the lads at Cardas made an error and end up sending my dealer the Cardas Clear Light XLR 4 pin balanced cable.
I have been researching on the internet for reviews for the Cardas Clear Light headphone cables for the HD800 with absolutely no luck.
My dealer suggested that I'd be better off getting the Cardas "Clear Light" XLR 4 pin Cable and the Cardas Quadlink Power cable for the same price as the Cardas "Clear" Headphone cable and that it actually will improve the quality of the sound more.
Any suggestions would be greatly appreciated.
 
Thanks gentleman
 
---------------------------------------------------------------------------------------------------------------------------------------------
 
I had a single ended Moon Audio Black Dragon V2 Headphone Cable that sounded good. Another Moon Audio Black Dragon V2 headphone cable is on the way, this time terminated with a Neutrik Single 4-Pin Male Gold XLR for the HDVD800. I use a Shunyata Venom 3 Power Cord. This combo comes in under the price of the Cardas Clear Light and Cardas Quadralink Power Cord combo. Something to consider possibly.
 
Jun 13, 2013 at 2:41 AM Post #914 of 3,016
Quote:
 
I have to say that the USB audio implementation sounds superb, at least to my ears and with my current set-up:
 
MacBook Pro 15 Retina > Pure Music > WireWorld Ultraviolet USB Cable > HDVD800 > HD800

 
You know, the HDVD800 just HAS to be using Asynchronous transfer mode for it's USB interface. Although I've not looked real close yet (kinda waiting for break in to be complete), this DAC seems to be extremely insensitive to USB digital cable variances-even for ground loop problems.
 
For systems using synchronous (or in the case of USB, Adaptive) forms of data transfer, I have personally experienced where on highly resolving systems, jitter artifacts can be very noticable and higher grade cables can help control it. However, on lower resolution systems, those artifacts may not even be noticeable and so putting really expensive digital cables on the system is a total waste of money since the resolution of your electronics and transducers just won't let you hear any benefit that the cables might provide anyway.
 
Another benefit of some of the more expensive digital cables is the ability to help reduce jitter and framing loss events due to ground loop noise. This is also quite real but again, with the exception of framing losses, If your system doesn't have the resolution to reveal the artifacts created by the jitter, upgrading from standard digital cables to more expensive cables probably won't get you any noticeable improvements.
 
I'm not trying to turn this into a discussion of cables (heaven forbid!)
eek.gif
 but it is relevant to my current observations. In the case of the HDVD800, if it is indeed running in Asynchronous transfer mode, then there should NOT be a significant difference due to cable. The only thing that I was expecting was potential ground loops that could transfer from a standard shielded cable INTO the DAC section of the HDVD800 and affect the DA converters or framing. For rather complicated reasons, I wound up with a 3meter length of Audioquest Coffee USB (retails about $500) to try out with the DAC/amp combo. As it turns out, in my initial (and brief) comparisons, I could detect no differences between that and a 1meter stock USB cable I got from Other World Computing (came with a hard drive I bought).
 
Now, the location of my gear is in a fairly "quite" area electrically speaking, so I didn't expect any ground loop issues. Again, from past experience with digital cables in an S/PDIF environment, something like the Audioquest Coffee could make a huge difference with some systems, but in an environment with minimal ground loop issues (i.e., MY current environment) a decent $15 USB may be all that is necessary to gain the best sound with the HDVD800. Now I am using the Beyerdynamic T1 in my setup and I'm sure it's not as revealing as the HD800. Once things are broken in, I might try and borrow an HD800 as see if things remain the same (my guess is they will, but that's just me)
 
Anyway, the one thing that seemed rather amazing to me was how well the clock recovery for the S/PDIF Optical seemed to work even when it was being pushed beyond its limit. It was very much like the USB interface (which of course is probably using an internal clock instead of the normally inferior S/PDIF clock recovery). Again, this is all been observed very informally on a partially broken in system. Even though at present my system is very clean and open sounding, there does seem to be a tad bit of congestion in imaging. If this opens up further with break in, then my guess is that any differences between the optical input and the USB input qualities may start to increase. Time will tell, I guess that's the fun of it.
 
- Jeff
 
Jun 13, 2013 at 2:59 AM Post #915 of 3,016
Quote:
I have been waiting for my Cardas Clear XLR 4 pin balanced cable for my HD800s & HDVD 800 combo for over a month from my dealer in Toronto but the lads at Cardas made an error and end up sending my dealer the Cardas Clear Light XLR 4 pin balanced cable.
I have been researching on the internet for reviews for the Cardas Clear Light headphone cables for the HD800 with absolutely no luck.
My dealer suggested that I'd be better off getting the Cardas "Clear Light" XLR 4 pin Cable and the Cardas Quadlink Power cable for the same price as the Cardas "Clear" Headphone cable and that it actually will improve the quality of the sound more.
Any suggestions would be greatly appreciated.
 
Thanks gentleman.

Hi there, I'm not an expert but just in case it helps, I also have the Cardas Clear XLR 4 pin. THINKER also has the Cardas Clear XLR 4 pin, and he's terrific at explaining his impressions. (you'll find some in the earlier posts) In my opinion, I suggest you wait for the clear cable to arrive. IT'S WORTH THE WAIT!
Because I'm not technically versed on it, I can only describe my impression - it sounds smooth and silky. Like bathing your ears in cream!!! Unfortunately, I only have the Cardas Clear Light in 1/4 inch so it's difficult to compare directly with 4 pin Clear. The Light in 1/4 inch sounds really fantastic, but the Clear Balanced is a phenomenal step up. Sorry I can't compare them as both balanced.
 
GET THE CLEAR!!!!!    :)
 

Users who are viewing this thread

Back
Top