Rotel HT receiver and RCD-1072 users....

[gianni]

Sorry this is so long, but I want to paint an accurate picture.

A little over a month ago I purchased a RCD-1072 to add to my RSX-1055. Prior to the 1072, I had been using a roughly 15 year old Denon DCD-1520 which at the time was one of their top of the line CD players...this thing weighs about 25 pounds, and a relatively inexpensive Sony NS500V DVD/SACD player.

After spending considerable time with speaker placement and addressing the most glaring of room problems, I did achieve pretty good sound. That is, a fairly well defined soundstage with good instrument placement and focus and fairly even bass response. With this setup, not unexpectedly, I got the best results by using the digital output from both players using the RSX-1055's DAC.

The RCD-1072 was then connected to the 1055's multi-input as I believe this is the only analog pass-thru with this receiver. This was a good setup for comparing players, as switching from multi-input to a digital source is fast, not requiring the digital input to re-acquire the digital feed. This allows for instantaneous comparison elimnating memory effect while comparing sources.
Also, I have 2 copies of 5 different high quality CD's eliminating the possibility of a "burned" CD affecting performance.

Initially the 1072 through the multi-inputs using it's own DAC's did sound different than the other players thru the digital feed. The 1072 was ever so slightly brighter and the midrange was slighty more forward in the sound stage. Strikes to cymbals, cowbells and claves seemed to have more body. However, after a month and a half of burn in, the 1072 is no longer brighter than the 1055's DAC. In fact, after several sessions consisting of many hours of A/B/A testing, the 1072 via analog and the other two thru digital feed are basically indistinguishable.

Now according to commonly held beliefs around here and from everything I've ever read on this subject, the 1072 with a torroid transformer and two quality Burr Brown DACs should produce better, if even though slightly, sound than the compromised setup in the 1055. What gives?

I have completly checked sytem setup and tried different cables and interconnects. Besides, if something was amiss, I do not think I would get the sound staging I do.

I can arrive at the following possibilities:

A- The 1055 though sounding good for a receiver, is coloring the music to a point that it is masking the differences between the 1072 and it's onboard DAC's. Perhaps either the preamp section or the amp section inside this big busy box is not clean enough.

B- Induction somewhere is blurring the signal.

C- Todays DACs have gotten good to the point that they are difficult to distinguish. But, you would think the 1072 superior analog section would prevail.

D- Rotel hit a home run and the 1055, which many have compared its preamp section to the 1066, is just better as a DAC than most people realize. Having a DAC next to the amp does eliminate interconnects and some outside noise sources.

E- The 1072 just isn't that good.

F- My room acoustics are bad enough to hide the differences. I doubt it though as I would not get any sound staging at all. It would sound more like a 2D kiosk cut out.

G- My ears are Lo-Fi.

Anyone have any thoughts? In any case, unless I get this resolved, It puts a BIG HURT on the argument for upgrading electronics for better performance.
DVD player and a digital connection and you are good to go. I am going to consult my dealer and then Rotel if need be. However, I do not get a warm fuzzy feeling.

[phuz]

If you are using the digital output from the other players into your 1055, then you are using the DACs in the 1055... which are very simmilar to the DACs in the RCD-1072. This might be why you are not hearing much of a difference, you are getting Rotel sound quality either way!

You'll need to use the analog output from your other players if you want to do a more reliable comparison, using the 1055 just as a pre.

[Aussie Geoff]

Hi,

Some thoughts. I had the same issue with my RCD-1072 and RSP-1098 and it started me thinking the same things as you.... My dealer said "what cables are you using".... Bottom line it started me on a journey which is documented in this thread... I found that with good digital cables I could get way better sound digitally... After a lot of trying I then found some analgue cables where the superiority of the RCD-1072 just shone through...

Worth a try

Geoff

[thyname]

If you are using the digital output from the other players into your 1055, then you are using the DACs in the 1055... which are very simmilar to the DACs in the RCD-1072.

Does this mean that if one owns a Rotel receiver with digital input you will not need a nice cd player at all and any universal player will do for redbook cd? Did I waste my money for my RCD-1072? Does not sound right!

[rick c]

From my understanding if you use the digital connection you will be using the dacs of the receiver,if you use the analogs you will be using the players dacs.I may be wrong on this but this was my understanding.There may be some variances but not much.

[thyname]

I understand it Rick, thanks a lot! Let me rephrase my question: Are the RSX-1056 receiver's DACs identical with RCD-1072 DACs? So if you already have a RSX-1056, any cheap universal player connected to the receiver through digital cable would be equal to the RCD-1072 connected to the receiver through analog cables, regarding redbook cd playback? Strange!!

[gianni]

Hi,

Some thoughts. I had the same issue with my RCD-1072 and RSP-1098 and it started me thinking the same things as you.... My dealer said "what cables are you using".... Bottom line it started me on a journey which is documented in this thread... I found that with good digital cables I could get way better sound digitally... After a lot of trying I then found some analgue cables where the superiority of the RCD-1072 just shone through...

Worth a try

Geoff

Geoff,

Thanks for the reply. At least its nice to know I'm not the only one who has experienced this. I'll read that thread. Also will see what my dealer has to say.

[gianni]

Does this mean that if one owns a Rotel receiver with digital input you will not need a nice cd player at all and any universal player will do for redbook cd? Did I waste my money for my RCD-1072? Does not sound right!

I'm really hoping this is not the case.

[gianni]

I understand it Rick, thanks a lot! Let me rephrase my question: Are the RSX-1056 receiver's DACs identical with RCD-1072 DACs? So if you already have a RSX-1056, any cheap universal player connected to the receiver through digital cable would be equal to the RCD-1072 connected to the receiver through analog cables, regarding redbook cd playback? Strange!!

No, they are not the same. The 1055 at least uses an AK DAC while the 1072 uses dual Burr Brown DACS. The question is - is the difference audilble when run through the receiver's multi-inputs?

[Aussie Geoff]

Gianni,

This is quite a complex situation. Two other key components affecting the analogue sound are the quality of the Op-Amps in both the RSX-1055 and also the RCD-1072.

The Op-amps are used to amplify the analog signal coming out of the DA in the RCD-1072 and then again in the RSX-1055 to process the signal. Again the RCD-1072 has better op-amps than the RSX-1055 but you won't fully hear that because it will be partially masked by the "not quite so good" op-amps in the RSX-1055.

Equally the quality of the regulation of the power supply is important as tiny noises and ripples transfer onto the sound, especially low level sounds such as line inputs. The RSX-1055, having to also do duties as a power amplifier is inherently compromised, as the power draws from the amplifier can interfere with the low level power supply to the pre-amp section (that's why people like separates). The RCD-1072 has high quality dedicated power supplies will much lower ripple and noise than the RSX-1055. Again this will be masked to some extend by the RSX-1055...

There is also the question of cables. I have found that a high quality digital cable made (for me) the digital sound much better than the anolog connection. But when I moved to an equally high quality analog connection, the superiority of the RCD-1072's DACs shone out... Of course all of this was on my RSP-1098 which has higher quality power supply, op-amps amps and DACs than the RSX-1055 - but I would expect the same effect to apply.

However, further complicating things, even if you decide to mostly use the RSX-1055 DACs and go digital - I have found (as have many others) that all digital signals are not the same. For example the digital signal from my RCD-1072 sounds way better than my older Sony ES series CD player, and incomparably better than my DVD player... There are lots of reasons for this, particularly varying degrees of digital jitter which affect the sound and good players spend a lot of effort on low jitter.

So what does all this mean:

• For the best possible stereo sound you need a dedicated stereo system with as few as possible components in the way of the sound.
• However your RCD-1072 will be delivering superior sound to the RSX-1055 when compaired to lesser CD players.
• The sound will be better over both analog and digital connections.
• A proportion of that superiority will be masked by the limitations of your RSX-1055 and the cables you use.
• You can partially address this by using higher quality cables. and often get remarkable improvements.
• Ultimately though, the RSX-1055 will be a limiting factor for stereo sound from the RCD-1072.

I hope this helps!

Geoff

[thyname]

Thanks a lot Geoff for the detailed and informative reply!!

My current setup (stereo only) is: Rotel RB-1080/RC-1070 and RCD-1072 with Axiom M60ti speakers (no sub). Sooner or later I am building my HT and am thinking of purchasing a RSX-1056, sell my RC-1070, as I cannot afford separates for HT. Again, I would be very interested in keeping the high stereo quality I have now with my current setup. Do you think that I would loose a lot replacing RC-1070/RB-1080 combo with RSX-1056/RB-1080 (at receiver preouts) for 2 channel redbook cd playback? Or, will I be better off keeping my stereo as it is now, probably in a living room, and just building a totally new HT in a different room? That will require a new pair of floorstanders, but is it worth it?

Thank you Geoff for your input, it will be greately appreciated! Anybody, please welcome to chime in!!

[RebelMan]

Initially the 1072 through the multi-inputs using it's own DAC's did sound different than the other players thru the digital feed. The 1072 was ever so slightly brighter and the midrange was slighty more forward in the sound stage. Strikes to cymbals, cowbells and claves seemed to have more body. However, after a month and a half of burn in, the 1072 is no longer brighter than the 1055's DAC. In fact, after several sessions consisting of many hours of A/B/A testing, the 1072 via analog and the other two thru digital feed are basically indistinguishable.

Now according to commonly held beliefs around here and from everything I've ever read on this subject, the 1072 with a torroid transformer and two quality Burr Brown DACs should produce better, if even though slightly, sound than the compromised setup in the 1055. What gives?

I am a little skeptical about Geoff's cable suggestion as a possible breakdown in sound quality. As you stated above the sound quality you heard initially seemed to diminish over time. Assuming all else being equal, I doubt your cables oxidized or deteriorated to the point where you noticed no difference between inputs a month and a half later.

It does seem rather unusual that now things sound the same, again assuming NOTHING else has changed with your system. There are two plausible possibilities here. One, the improvements you thought you heard from the outset really were not there. Two, you have grown so accustomed to both configurations from repetitive A/B/A testing that the sounds you hear now are the effects of mental smearing, perhaps a mild form of psychoacoustics.

Needless to say, your early observations of the RCD-1072 are consistent with mine with the exception that what I noticed still hasn't changed. While equipment that goes through a break-in period will adjust and acclimate to the surrounding atmosphere, changes to sound is generally insignificant. This of course assumes the equipment has reach normal operating temperatures before critical listening is conducted.

To reassure the doubtful mind, the RSX-1055 is a good receiver and coloration of the signal is possible but unlikely a change to what you hear and yes, the RCD-1072 is that good.

There is another possibility, but this assumes that something HAS changed with your setup. Digital signals are notorious for crosstalk interference with analog signals. I suggest that you completely isolate ANY and ALL digital IC's from analog ones. I suspect if anything would make a difference to the quality of your input signal, and ultimately the sound you hear, this would be it.

[RebelMan]

thyname, you seem really uncertain about what to do regarding your delima. I suggest you make arrangements with your local dealer for an in home demonstration of the RSX-1056 to help you determine what decisions you should make.

Usually a dedicated stereo system will perform better than a mixed two-channel and multi-channel system will, but there are exceptions. The RC-1070 is a fine product but so is the RSX-1056. I believe the RSX-1056 will give the RC-1070 a run for the money and I don't believe you will lose much if anything. Ultimately, only you can decide if it (RSX-1056) is worth it. :wink:

[Aussie Geoff]

I am a little sceptical about Geoff's cable suggestion as a possible breakdown in sound quality. As you stated above the sound quality you heard initially seemed to diminish over time. Assuming all else being equal, I doubt your cables oxidized or deteriorated to the point where you noticed no difference between inputs a month and a half later.

Just for clarity - I am not trying to say the cables have oxidised causing differences over short time. Indeed I support your theory that the reduced differences over time will be due to a combination of equipment break in and the "ear" adjusting to the new sound. What I was trying to focus on is why there was now little or no difference between the sound via digital and analog connections from the very good RCD-1072. I gave a whole raft of factors that will help mask differences and offered that one of them, that I found surprisingly beneficial, was the quality of the cables. For example a better digital cable than analog made the digital connection from the RCD-1072 sound better until I upgraded the analog cable to a sufficient quality to reveal the differences... Other things like power conditioners helped clean up the sound from both...

Try it and see. Borrow a really good digital coax cable and compare it to a cheap one and see what you can hear... I was amazed as were by family...

Geoff