Transports again

[Mr Peabody]

I am using my Krell 280cd as a transport in my main system. I wanted to take it out and use it in a second system in order to upgrade there and make use of the Krell's DAC. I also wanted to take the upgraded power cable off to use else where. I have an older upper end Denon I was going to use as a transport in the Krell's place. This Denon must weigh 30 lbs. Well to my surprise, with the Denon in place the sound quality wasn't as good. All things were kept the same while listening, the volume didn't even change. With the Denon as a transport the music wasn't as snappy and the bass decreased. So this experience has put me in the camp that maintains there is a difference in sound between different transports. I was really hoping I wouldn't hear a difference. I really did not want to open this can of worms but this experience was quite a revelation for me.

[nightflier]

This may very well be the internal dac of the Denon, especially if its a much older unit. See if you can borrow a good quality dac and it should improve the sound dramatically. I currently use an MSB dac with upgrades, which I bought second hand. This is an excellent dac for the money, but any external dac will work wonders. Check out some of the ones from CAL, Parasound, Arcam, Musical Fidelity, Aragon that are flaoting around eBay & Audiogon for less than half their new prices. My guess is that with even a $100 Parasound dac (used price), the sound will be vastly improved.

[Mr Peabody]

Let me clarify, I use an Audio Note DAC in my main system. I prefer it's sound to the Krell's internal DAC. Using the Denon and Krell's digital out to the AN DAC I could hear a difference between the transports.

There could be something to the fact that the Denon is older, I'm sure there's more to the transport than what I know.

[E-Stat]

There could be something to the fact that the Denon is older, I'm sure there's more to the transport than what I know.

There's something more to the sound of transports that anyone (as yet) knows. Much like those who said that turntables have no effect on sound.

rw

[Woochifer]

There's something more to the sound of transports that anyone (as yet) knows. Much like those who said that turntables have no effect on sound.

rw

Who has ever said THAT? I've certainly never read anything to that effect. Even the most ardent objectivists I know would acknowledge that turntables are much more audibly susceptible to external factors than CD transports.

[E-Stat]

Who has ever said THAT? I've certainly never read anything to that effect. Even the most ardent objectivists I know would acknowledge that turntables are much more audibly susceptible to external factors than CD transports.

Isolation and feedback effects aside, there are / were plenty of folks who denied sonic differences exist of a tonal and/or noise floor nature. I remember first hearing the debate back in the 70s when the Linn Sondek LP-12 was introduced. The notion of a turntable having a "sound"? A Linn Sondek sounds different from a Thorens which sounds different from a VPI which sounds different from a Clearaudio which sounds different from a Kuzma which...

My current VPI Scout has a more neutral (leaner) mid bass and better low bass than the Ariston RD-11s (very similar to the Linn) it replaced. Its noise floor is lower as well improving resolution.

rw

[nightflier]

Mr. Peabody,

Well that does change matters. Typically with old CD players, it's the dacs that are the most audibly different. The AN dac eliminates that factor.

Here's a simple and inexpensive test you should try: put a mouse pad on the Denon player to protect it, and then a heavy object on top (a couple of encyclopedia volumes ought to do it). If the sound improves, then it's probably a vibration issue.

[RGA]

I am in the camp that DACs make a difference but have had less luck hearing transport differences -- that said my experiences with Transports have been smaller and of course just comparing an expensive one to a cheap one is hardly indicative -- lots of very expensive equipment is just not very good. In my case it was a pricey Wadia and Pioneer 300 disc changer both running a Cal Labs Dac and heading through $10k Electrostats.

My experience with the one box Audio Note 3.1 versus - well every other cd replay device I have ever heard over the last 20 years is that it's the only one so far that I enjoy listening to music on -- to that point anyway since I have heard a Dac 4.1 Balanced signature and CD Two Two transport since. The DAC transport combination will be the next thing I do when I get back to Canada.

Bob Neil liked the AN Transports but apparently really really likes the new transports from AN -- but they are pricey -- but not really when comparing to less robust units for more money from some others. I can't say whether they are better -- I have not done testing on the transport differences in isolation so I would advise that first. Being big and hevey is not the only thing that matters -- too much audio jewelry and not enough sonic chops IME from most stuff out there. I would give it a try since it is designed for their DACs http://www.audionoteusa.com/CDtransports.htm

[teledynepost]

Is the transport just the reading of the disc, before any analog conversion? There should be no difference.

[RGA]

There is disagreement among engineers on what the transport does. For Audio Note the set-up is a one time through process and they use no error correction or oversampling or jitter reduction or re-clocking etc because they believe in preservation of the time domain and that music should not be sliced diced and re-corrected and or noise shaped. Thus for that design it could make a lot of sense that a transport plays a very important role. But for a DAC that reformats everything through some sort of buffer then that Digital to anolog device may make all transports sound the same. To me one has to determine if the price paid yields an improvement big enough to be worth it. The Wadia to me was so expensive and the 300 disc changer so cheap and mor euser friendly that even if I really strained and could hear the Wadia was slightly better(or just different) it just wasn't big enough to warrant that 10 times the price difference. If there is one thing above all others that AN does the best IMO is digital replay and just about the only thing that works well in any system not just their own. The rest kind of needs to be together.

The design is different as you can see in this article and Mr. Peabody has this DAC which means the transport MAY play a bigger part than with some other DACs.
http://www.audionotekits.com/agrovedac.html
http://www.dagogo.com/AudioNoteDAC5History.html
(I am no engineer but I go with my ears and my ears tell me that their DACs make music sound right and to be blunt I have heard nothing else sound as good including top players from YBA, Sony, Linn, Arcam, etc.

[Mr Peabody]

Good point that the amount of difference heard between transports could very well depend on the DAC used. In every experience I've done, which really isn't much, I've heard a difference between transports. A friend of mine uses a Levinson DAC and has tried different transports and says he hasn't detected a difference. He also notes that Levinson has a buffer or clock that makes all the signals have the same speed which could even the playing field.

I have a solid state Conrad Johnson DAC that I use the Denon as a transport. I tried to use a TDK CD recorder with this DAC while I made some comps and the TDK using digital out sounded like crap. I thought since the TDK was cheap could be the reason. I think maybe the difference I experienced between the Krell and Denon into the AN DAC may be that the Krell is a few years more modern. But as E-stat mentioned, no one really realizes yet what all a transport does. The difference could be attributed to something else we are not aware of.

I don't know what or why, but all digital is not the same. I also experienced an incapatibility problem between my cable box digital out and my Primare processor. The processor worked fine with satelite box. If digital is the same how can you account for that? That's just a data stream, no transport or other interference.

[hermanv]

The Redbook process (that's the format and details for how to put bits on a CD) has extensive error correction. Several layers. These layers are in the transport not in the DAC. Presumably the reason for extensive error correction is that significant error rates were expected.

If the errors are great enough, the error correction chips fill in or extrapolate missing bits, it is very likely that the mechanical quality of a given transport would influence the number of bit errors.

Having said that, it appears from the small amount of testing I've done that most transports have few enough errors that the error correction circuits do a good job of recovering a relatively error free datastream from the disk. i.e. With my well buffered and re-clocked DAC all the transports I've tested sound the same. Of course there a really only a very few dedicated transport makers, so for all I know the different players I've tried might have had identical mechanicals inside.

So once a low enough error rate is reached further improvemennts may not be audible. I have wondered for years why error rates are never listed on transport reviews or tests, yes its a pain, but it goes to the fundamental question of how well a given piece of hardware recovers a data stream from a CD.

In a computer, CDROM drive errors don't happen becasue the computer software just goes back and re-reads that same track until it gets good data, this is mostly not possible in real time data streams producing music. There are a few players that buffer and re-read bad bits but the acoustic delay has to be small, so the amount of re-reading must also be small.

Any Redbook experts out there? Can you help?

[thepogue]

Hey all hope things are well in the audio world and on the home front as well!! My experience is that the DAC is the major factor…and in fact I've got a Theta Voyager in my system that I'm thinking about picking up for use as a CD transport only but I'm not overly impressed by the $6,500 Theta (even if it can be had for 1,200) I do realize that the lil Adcom DAC isn't really doing the Theta justice but it's all I have on hand…anyone got any thought's?? (sorry for the minor hi jacking) I've just got mixed feeling what I'm going to be gaining for the $1,200…and I'm not at all interested in the DVD/Laser side of the transport…any thoughts would be cool…once again nice to see all you smiling' faces and sorry for the minor detour!
Peace, Pogue

[RGA]

The Redbook process (that's the format and details for how to put bits on a CD) has extensive error correction. Several layers. These layers are in the transport not in the DAC. Presumably the reason for extensive error correction is that significant error rates were expected.

If the errors are great enough, the error correction chips fill in or extrapolate missing bits, it is very likely that the mechanical quality of a given transport would influence the number of bit errors.

Having said that, it appears from the small amount of testing I've done that most transports have few enough errors that the error correction circuits do a good job of recovering a relatively error free datastream from the disk. i.e. With my well buffered and re-clocked DAC all the transports I've tested sound the same. Of course there a really only a very few dedicated transport makers, so for all I know the different players I've tried might have had identical mechanicals inside.

So once a low enough error rate is reached further improvemennts may not be audible. I have wondered for years why error rates are never listed on transport reviews or tests, yes its a pain, but it goes to the fundamental question of how well a given piece of hardware recovers a data stream from a CD.

In a computer, CDROM drive errors don't happen becasue the computer software just goes back and re-reads that same track until it gets good data, this is mostly not possible in real time data streams producing music. There are a few players that buffer and re-read bad bits but the acoustic delay has to be small, so the amount of re-reading must also be small.

Any Redbook experts out there? Can you help?

That's just it the experts don't agree. It would seem to me that if one owns a DAC that buffers everything and reconstructs it then no matter what transport you use the same results will ensue -- and if you like the sound of the DAC then buy a very cheap transport and be happy. The reason over sampling was creted in the first place was because of all the burst errors that occurred in the early players -- so the machine reads the disc samples it over and over to make sure it gets all the information -- Audio Note claims this is is bad because music runs on a time continuum and this method merely slugs the sound down and leaves an interpolated signal that has been created to make the measured results look good... all of that could be complete BS of course but upon hearing it for myself I do not disagree with the results. (well of the DAC because I have not really experimented with the transports -- and like I say it may simply be a different enough design).

Yes there is error correction pre built into the compact disc but not all of it. Much is still carried out by the rest of the player. AUdio Note uses no anti-jitter techniques -- it reads the disc once and only once and it does not go backl and re-read to make sure it got it right becaus eit gets it right the first time and it passes that directly to the Dac without correcting what it read with noise filters and noise shapers and bit fixer uppers and fill in the blank information. No re-clocking to get the dac in sinc with the transport. And in spite of all of that when playing if you go up and hit the machine it does not skip or groan or anything else. These transports are made by one of the big guys - Sony I believe - and the upper one uses the Philips Pro transport with upgraded internals and power supply.

The best way to tell of course is to go out and try it and see or umm hear for yourself if they actually do anything different. I can;t at the current time because I am in Korea.

[Wireworm5]

For me I notice that the source sounds better using optical (Digital) instead of RCA cables (analog). I don't know if this is because it is digital or that my Yamaha DAC is better than any of my sources.

[Woochifer]

For me I notice that the source sounds better using optical (Digital) instead of RCA cables (analog). I don't know if this is because it is digital or that my Yamaha DAC is better than any of my sources.

That could be due to differences in the DAC used, but also any number of other factors. For example, if you connect the analog output from a CD player to a AV receiver, then it might go through a redundant AD/DA conversion in order to route the signal through the DSP, bass management/crossover, and volume controls. Only receivers that use an analog bypass and have the bass management switched off avoid the redundant conversion chain.

Another factor could simply be that the signal is louder when using the digital connection. Try level matching the output, then see what differences you hear.

[Mr Peabody]

Further evidence to my ears of differences in transports. I found an EAD T-1000 and picked it up in hopes it would be close to performing as well as my Krell 280cd's digital out. The T-1000 was used to drive some much more expensive DAC's and got good reviews in tandum with the EAD DAC, which model# escapes me now. Well to the point, with the T-1000 in place, to my amazement I actually preferred it. To some the difference would be a matter of preference. The Krell still projected a more substantial sound, having more weight and slightly larger sound stage. The EAD produced more of a sense of pace, quieter background with more air around instruments and a bit more natural tonal quality. Perhaps the EAD was able to be more neutral or what I hear from Krell is their use of extreme current in everything they build.

These two transports, with everything else being the same, gave quite a bit different presentation. I'm confident that anyone who would be able to hear these could tell the difference. I've done enough playing now with DAC's and transports to be completely convinced there IS, or can be, big differences in transports. I think this knowledge disturbs me more than anything. Now my quest is to hopefully some day understand why there is a difference.

Just as a side note, I find it interesting as I gradually remove pieces of Krell out of my system, that even the slightest of Krell can still influence the sound. This could be said of almost any component in or out of a system but not in the same way as Krell, I really don't have the words to accurately express my thought here. Maybe a better way is to say the influence is not just a change in sound, but a change in almost a dominent way. My conclusion would be if you are going to use Krell components, synergy with the other components in the system will be most critical.