The only analog inputs that are guaranteed not to be digitized are the multichannel (7.1) analog inputs.
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Review and Measurements of Marantz AV8805 AV Processor
- Thread starter amirm
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Pretty sure the other analog inputs are not digitized (based on the schematics) too if you engage pure direct, not sure about direct.
Perhaps. I have had some conflicting comments and test results regarding the XLRs.
I suppose the reticence comes from the difference that is observable in some AVR/HT processors between "Pure/Direct" (and similar named functions) and Stereo (presumably with additional circuitry enabled). I have had many AVR/Processors where switching between Pure/Direct and Stereo (all settings flat) the alters the sound. No DBT (sorry). Try it sometime
Here are the specifications for the XMC-1 analog Reference Stereo and analog with DSP's engaged:
-THD: <0.0005% @ 1 kHz.
-THD: < 0.002% (20 Hz to 20 kHz).
- IMD: < 0.004% @ 1 kHz.
-S/N ratio: > 123 dB (A weighted).
-Frequency Response: 5 Hz to 80 kHz (+0 / -0.1 dB).
-Crosstalk: <100 dB.
Analog Inputs to Analog Outputs via Digital Signal Path
(modes that include processing or bass management):
-THD: <0.0007% @ 1 kHz.
-THD: < 0.0007% (20 Hz to 20 kHz).
-IMD: < 0.005% @ 1 kHz.
-S/N ratio: > 106 dB (A weighted).
The distortion numbers are very low in both cases but the S/N increases by 17dB (A weighted).
I can do a SBT on this but there are observations that are so obvious, even SBT is not required.
There may be products that are transparent with DSP's engaged but I suspect many are not.
The choice then becomes a cost/benefit which still favors processing in most environments.
Also included in the easily recognizable is engaging Dirac with the curtain set to 25hz (meaning little or no alteration).
None of this is conclusive, but I do believe that folks can and should try these products at home and make up their own mind.
- Rich
I don't know if I should post the schematics but they are available at hifiengine.com. As mentioned before, it is selectable via the NJU IC switch.
I think you have to look at the available functions and which are available by input for clues.
All Channel Stereo, double-bass, bass management (in many cases), etc. are not available for the 7.1 analog inputs but are available for other analog inputs.
- Rich
That's exactly why I said it was most likely the case only if pure direct is selected. In the older Denon, such as my AVR-3805 and the 4308 too I think, you can also select "analog". By the way, I just try direct, it looks like it goes straight too because all audio functions are lost except volume, only when analog inputs are used obviously.
Pure Direct selected limit intentionally limits functions but that may not indicate there is no A/D in all cases.
It is only when those functions are never available that there is no A/D conversion possible.
Pure Direct on my AV8801 XLR in's was more of a suggestion because other functions like double-bass could be set and worked in Pure Direct. So, you can get A/D but it is unclear which functions trigger it. I suspect this is the reason that it difficult to get a straight answer from manufacturers concerning A/D with Pure Direct.
Emotiva has Reference Stereo that does not do A/D conversion on the XLR inputs.
- Rich
I suppose the reticence comes from the difference that is observable in some AVR/HT processors between "Pure/Direct" (and similar named functions) and Stereo (presumably with additional circuitry enabled). I have had many AVR/Processors where switching between Pure/Direct and Stereo (all settings flat) the alters the sound. No DBT (sorry). Try it sometime
Here are the specifications for the XMC-1 analog Reference Stereo and analog with DSP's engaged:
-THD: <0.0005% @ 1 kHz.
-THD: < 0.002% (20 Hz to 20 kHz).
- IMD: < 0.004% @ 1 kHz.
-S/N ratio: > 123 dB (A weighted).
-Frequency Response: 5 Hz to 80 kHz (+0 / -0.1 dB).
-Crosstalk: <100 dB.
Analog Inputs to Analog Outputs via Digital Signal Path
(modes that include processing or bass management):
-THD: <0.0007% @ 1 kHz.
-THD: < 0.0007% (20 Hz to 20 kHz).
-IMD: < 0.005% @ 1 kHz.
-S/N ratio: > 106 dB (A weighted).
The distortion numbers are very low in both cases but the S/N increases by 17dB (A weighted).
I can do a SBT on this but there are observations that are so obvious, even SBT is not required.
There may be products that are transparent with DSP's engaged but I suspect many are not.
The choice then becomes a cost/benefit which still favors processing in most environments.
Also included in the easily recognizable is engaging Dirac with the curtain set to 25hz (meaning little or no alteration).
None of this is conclusive, but I do believe that folks can and should try these products at home and make up their own mind.
- Rich
I have, and am well aware that it alters the sound. For better or worse depends... Not sure I could hear the difference between 123 and 106 dB in my system but I tend to look at unweighted noise and the spectral content more so than A-weighted ratings. Many times I suspect the biggest difference is what room correction does (or does not do) to the sound. People used to their room and the sound it creates may not like any change.
Whatever - Don
Processors *should* be capable of no audible difference with between processed flat and Pure Direct.
The higher end processors are removing analog inputs or digitizing them so comparison is difficult.
An external reference is required.
Dirac on the XMC-1 or the DSP processing engaged is definitely altering the sound stage and not something I liked. However, I was able to use PEQ to smooth out some bass frequencies without the same changes. I don't know if the change was due to Dirac, the XMC-1, or both.
Many are running this REQ software until they like the sound. Not very scientific. Predicted response is bias generating.
I use REW to measure the before and after and to listen to unprocessed versus processed. My room is pretty good so, thus far, I have selected unprocessed.
- Rich
Different strokes... I like Dirac Live but tweaked the curve via ears and measurements to something I liked. It will "always" alter the sound when engaged so I expected that; I never imagined it would not since even with a flat curve it is altering things to make it flat as well as tweaking amplitude and phase. Sounds like you are a good example of an audiophile who does not like any processing and that's a personal preference.
I certainly have not heard/measured all AVRs/processors. I have barely listened to my XMC-1 in its reference pure or whatever mode -- my room needs correction. Most AVRs have different gain (level, volume) in their "pure direct" mode and that may account for some of the difference. I don;t really care, just going for something I like, and this discussion like many others is probably off-topic w.r.t. the 8805 review.
One thing I try to remember is that, below a certain level, specs don't matter much anymore since artifacts are inaudible. E.g. 140 dB SNR is 100x better than 120 dB but in the real world I couldn't tell the difference. Marketing. The problem is when folk don't know when a spec matters and at what level -- that is where buying by numbers falls down. Features and other things may swap the aforementioned SNR difference but your average consumer may not know and the salesman, who may or may not understand, does know how to sell the numbers.
I certainly have not heard/measured all AVRs/processors. I have barely listened to my XMC-1 in its reference pure or whatever mode -- my room needs correction. Most AVRs have different gain (level, volume) in their "pure direct" mode and that may account for some of the difference. I don;t really care, just going for something I like, and this discussion like many others is probably off-topic w.r.t. the 8805 review.
One thing I try to remember is that, below a certain level, specs don't matter much anymore since artifacts are inaudible. E.g. 140 dB SNR is 100x better than 120 dB but in the real world I couldn't tell the difference. Marketing. The problem is when folk don't know when a spec matters and at what level -- that is where buying by numbers falls down. Features and other things may swap the aforementioned SNR difference but your average consumer may not know and the salesman, who may or may not understand, does know how to sell the numbers.
Just to be clear, I am not comparing Pure/Direct to an REQ "Flat" curve. I am comparing Pure/Direct to Direct will all tone-controls flat which should produce an inaudible difference even with the 17 dB loss in S/N. I'll check the gain to make sure it is the same.
I keep holding out the hope that as DSP's improve, perhaps there will indeed be an inaudible difference with DSP engaged.
I much prefer PEQ to REQ with XMC-1.
- Rich
I had to dig up my XMC-1 manual. It looks like "Reference Stereo" is purely analog and "Direct" goes through ADCs and processing to handle bass management. "Stereo" adds tone controls and such, thus additional processing. So, different signal paths, different results. Whenever you stick processing in there is the potential for changing something, even if it is just levels. When you add bass management you add crossovers (now implemented digitally) and there is probably gain-ranging going through the processor.
I have no idea what the Marantz does.
I have no idea what the Marantz does.
As I mentioned before, if the analog inputs are used, the signal would not go to the ADCs in pure direct and direct modes. You can have the subwoofer on but you won't be able to use dsp surround modes, audsyssey, or graphic EQ.
Use "Direct" mode to bypass ADC/DAC processing. Use "Pure direct mode" not only to avoid ADC/DAC but to get less interference from digital electronics as display, video switcher and processor will be disabled. In these 2 modes your AV8805 will act as an analog preamp as signal passes only through volume control.
http://manuals.marantz.com/AV8805/NA/EN/DRDZSYyrtgycpw.php
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On pretty much all AVRs I have seen multi channel inputs always bypasses ADC/DAC stage and are routed directly to volume control.
I don't want to belabor this point, but there are other settings, such as double-bass, available in pure direct mode. I doubt there is additional analog circuitry to accomplish this. Therefore, Pure Direct *may* perform an A/D conversion based on other settings.
On these processors, the 7.1 analog inputs are the only ones guaranteed to remain analog, there is no A/D hardware for them.
- Rich
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My biggest complaint on the 7701 and 7703 is the remotes el-cheapo LCD display. Barely readable from any angle, LCD displays were better back in the 1990s. From what I can see on the internet the 880X uses the same remote. On such expensive PrePro's can't Marantz spend a bit more for a better display?
Agreed, that does seem to be the case.
BTW, @Blumlein 88 measured the 7701 to be exactly the same in the Direct mode and Pure Direct mode???
https://www.audiosciencereview.com/...tz-avr-7701-dac-measurements.3485/#post-84100
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