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Denon DRA-800H Review (Stereo Receiver)

peng

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If I'm not wrong the price of a AKM4458 chip is less than $4 if you buy a stock of 500 units (https://www.digikey.it/product-deta...K4458VN/974-1082-1-ND/5287011?cur=USD&lang=en), while the PCM5100A sells for less than $2 (https://eu.mouser.com/Texas-Instrum...s/PCM5100A-Series/_/N-4gxke?P=1yye73wZ1z0zls6).
I guess that using a more complex DAC like the AKM4458 has also an impact on the layout (and the cost) of the PCB. Anyway, to save a few Dollars Denon has decided to provide a lower quality audio output to ZONE2. At the end this is also resulting in a really bad advertisement for the DRA-800H considering that Amir in his review could only evaluate the PCM5100A output.
This is an important piece of information, at least for me. I was considering to buy a Class D amplifier based on Hypex NC252MP or NC502MP and to connect it to the ZONE 2 output but at this point it would be a complete wast of money.
Denon, I'm really disappointed...

If you look at the photos of the equally ugly power supply transformers for the DRA-800H and the NR1200, you probably would be turned right off and those very nice AK4458 implemented in differential connections with the also very nice NE5532 (typically not found in AVRs) wouldn't matter any more.:D

I would stick with an AVR regardless of the nice function over form thing. AVR-X3700H+NC502MP seems like a great value based on $, W and SINAD:D, just grab the best RCA to XLR, such as those by March Audio, Benchmark, but the Monolith ones look very good, and cheap.

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peng

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I don't beleive Denon added this crappy Volume Chip (NJU72343) after the DAC. 10%THD at -30dB! What about the quiet details?
Another one is the input selector. :( :( Why they just don't digitize evetything with a good ADC and drive the poweramp without these "detail killers"?
Don't understand them...

Are you reading them right? The NJU72343 are also used in the flagship Denon AVR-A110, and the Marantz AV8805A. Nothing beats the SINAD measurement of the AVR-X8500H's preamp/DAC yet !! All of the Denon AVRs and Marantz AVRs/AVPs on the chart use the same NJU72750 for switches and the NJU72343 for Volume control.

Take a look:

The Denon is still top of the ranking chart as titled AVR/Processor SINAD, if you ignore the NAD M33 and the Minidsp SHD that really are not what everyone would consider to be an AVR or AVP.

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peng

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Today I decided to open my own device, took a lot of close pics and turned to be very disappointed with Denon :(. They seems just replaced the NE5532 OPAs with cheaper mediocre JRC8080. :( Seems that they sent the "premium" version only for listening testers?
They also changed the 2x PCM5101 DAC to the downgraded version of PCM5100. Please seem my photos below.

Thanks to @bloodshoteyed, the service manual seems to indicate there are two versions, the E3 has the NE5532 and the E2 has the NJU8080.
If I were to guess, that I know I shouldn't, E3 seems to be the 120 V version and E2 the 230 V as indicated on sheet 21.

Regarding the PCM5100 and 5101, there is very little difference. The 5102 is the better one, but mainly better in SNR/DR THD+N/SINAD is only 2 dB better than the 5100 and 1 dB better than the 5101.

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ttt

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Thanks to @bloodshoteyed, the service manual seems to indicate there are two versions, the E3 has the NE5532 and the E2 has the NJU8080.
If I were to guess, that I know I shouldn't, E3 seems to be the 120 V version and E2 the 230 V as indicated on sheet 21.

Regarding the PCM5100 and 5101, there is very little difference. The 5102 is the better one, but mainly better in SNR/DR THD+N/SINAD is only 2 dB better than the 5100 and 1 dB better than the 5101.

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@peng : from where do you see it in the service manual? It has nonly 2 pages, block diagrams only what I downloaded here from the attached file by @bloodshoteyed .
The above Hungarian site tested version has 5532, and in EU running on 230V AC. I also bought here, mine has 8080.
So, finally, there is not possible to provide such bad 15bit linearity and SINAD with that 32bit AKM chip and the dual-differential setup. No way, it cannot produce this output. Even goes through the crappy analog switch ICs.
However it is very very likely the PCM5100. There was somewhere here a DAC measurement previosuly with the same PCM chip, with the same 15bit linearity problem, I can find if needed. It is much closer to the results measured.
 

peng

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@peng : from where do you see it in the service manual? It has nonly 2 pages, block diagrams only what I downloaded here from the attached file by @bloodshoteyed .
The above Hungarian site tested version has 5532, and in EU running on 230V AC. I also bought here, mine has 8080.
So, finally, there is not possible to provide such bad 15bit linearity and SINAD with that 32bit AKM chip and the dual-differential setup. No way, it cannot produce this output. Even goes through the crappy analog switch ICs.
However it is very very likely the PCM5100. There was somewhere here a DAC measurement previosuly with the same PCM chip, with the same 15bit linearity problem, I can find if needed. It is much closer to the results measured.

As I said it was on sheet 21 of the service manual. If you cannot access hifiengine.com, you can buy the service manual for about $10 online.

The question is no longer about the AK4458 dac and the NE5532 opa, we agree those should measure well.

The real issue is the fact that it has no main zone pre out and for some reasons the power amp measured poorly.

If you can still return it, you probably should, then buy the Marantz NR1200 and use the pre out with a good power amp.
 

peng

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@peng : from where do you see it in the service manual? It has nonly 2 pages, block diagrams only what I downloaded here from the attached file by @bloodshoteyed .
The above Hungarian site tested version has 5532, and in EU running on 230V AC. I also bought here, mine has 8080.
He did not post the whole service manual, probably just doing the right thing..;)

There are 143 pages (you can buy it for €7.96):


I am not sure exactly what E2 version mean, it may be for only certain countries that use 230 V.

There are many countries outside of Europe that also use 230 V, for example, many in Africa, Asia, Australia, Middle East and South America.

The NE5532's SINAD won't be much better than the NJM8080G, but it is certainly much better in slew rate, though the NJM8080G's slew rate should be more than high enough for the application. I agree with you, that if the preamp/DAC of the main zone can be measured, it would have been good. If our assumption is correct, that we are still missing the reason(s) why the power amp measured so poorly even when using analog input and in pure direct mode. 78 dB SINAD may still be good enough but it should be in the mid 80s like its AVR cousins. Something is not right!!
 

ttt

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He did not post the whole service manual, probably just doing the right thing..;)

There are 143 pages (you can buy it for €7.96):


I am not sure exactly what E2 version mean, it may be for only certain countries that use 230 V.

There are many countries outside of Europe that also use 230 V, for example, many in Africa, Asia, Australia, Middle East and South America.

The NE5532's SINAD won't be much better than the NJM8080G, but it is certainly much better in slew rate, though the NJM8080G's slew rate should be more than high enough for the application. I agree with you, that if the preamp/DAC of the main zone can be measured, it would have been good. If our assumption is correct, that we are still missing the reason(s) why the power amp measured so poorly even when using analog input and in pure direct mode. 78 dB SINAD may still be good enough but it should be in the mid 80s like its AVR cousins. Something is not right!!
Mine is 2y old :( can't return.
Thanks but don't plan to pay for it, if it can be downloaded from hifiengine for free from a right place/network. Probably if something goes wrong.
The SINAD is definitely wrong even with direct modes, where there shouldn't be any digitization, only the above mentioned 1x analog switch + volume chip in signal path. I don't like them, you can't find similar crap silicons in medium or up audiofil amplifiers, because of good reasons.
Anyway, there is no excuse fo this bad SINAD, probably the base idle current is low for the poweramp transistors / or the switching power supply noises the mentined chips? Who knows.
 

GiBo61

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My Denon DRA-800H is not connected to an external TV. Apparently, according to the manual, is it possible to send the audio signal to a TV using the ARC HDMI out (see screenshots below). I've not tried this yet since my TV set is far away from the Denon.
If all this is really working, I'm wondering if it possible to extract from the ARC HDMI out the digital audio signal and "convert it" in an Optical Toslink SPDIF format with a HDMI deembedder like the one shown below. I'm also wondering what is the quality in terms of word length and sample rate of the digital signal extracted (from HDMI specs should be up to 24 bit/192 kHz).
Since the network streamer section of the DRA-800H is complete, works well and is extremely flexible, the idea is to use it as a source and connect it to a decent external DAC (LOXJIE D30) and then to a power amplifier such as the AUDIOPHONICS HPA-S250NC Stereo Class D Amplifier NCore 2x250W 4 Ohm. Alternatively, is there a decent DAC with a HDMI input (possibly cheaper than the Essence HDACC-II4K https://www.essenceelectrostatic.com/product/hdacc-ii-4k/)? ) to use for this purpose?
 

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Rc Lobarniz

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I bought this unit years ago, I find the test results truly shocking. If there is something I like about this unit is how it sounds and the results show that I might be deaf , on the other hand I have always find this unit lacking enough power. I have a pair of Monitor Audio SILVER 100 and this amp provides just the power needed, no more. Completely flabbergasted.
 

GiBo61

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I bought this unit years ago, I find the test results truly shocking. If there is something I like about this unit is how it sounds and the results show that I might be deaf , on the other hand I have always find this unit lacking enough power. I have a pair of Monitor Audio SILVER 100 and this amp provides just the power needed, no more. Completely flabbergasted.
I share the same feeling of being deaf. Maybe I should get a cheap Sonos system and avoid future waste of money on HiFi devices. On the other hand I have never found my DRA-800H lacking in power, it can easily drive my Elac Vela BS403 (less than 86 dB at 2,83 V/m) to a painful volume in a 25 square meter room.
 
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Rc Lobarniz

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I share the same feeling of being deaf. Maybe I should get a cheap Sonos system and avoid future waste of money on HiFi devices. On the other hand I have never found my DRA-800H lacking in power, it can easily drive my Elac Vela BS403 (less than 86 dB at 2,83 V/m) to a painful volume in a 25 square meter room.
Hi, I think it lacks power depending on the source, cd are OK as long as they are not classical music, when it comes to playing movies I have to turn the dial to 0.00 dB, yes you are guessing right I'm deaf :cool:.
I can normally play music at - 20 dB and it's enough, it's the tv/films that this unit struggles with, even if I have set the gain, off the top of my head to +10db.
I thought it needed clarification, FYI other than that super happy with this unit.
I have connected a 1TB hard drive through the front USB and I find this feature over the top.
Regards.
 

GiBo61

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Hi, I think it lacks power depending on the source, cd are OK as long as they are not classical music, when it comes to playing movies I have to turn the dial to 0.00 dB, yes you are guessing right I'm deaf :cool:.
I can normally play music at - 20 dB and it's enough, it's the tv/films that this unit struggles with, even if I have set the gain, off the top of my head to +10db.
I thought it needed clarification, FYI other than that super happy with this unit.
I have connected a 1TB hard drive through the front USB and I find this feature over the top.
Regards.
I guess that the the input signal for some of the sources you are using is for some reasons too low. Even in my case the level of the devices connected with toslink or coaxial digital is much lower than the analog sources. If you play the Denon using one of the various HEOS services available (TuneIn radio, Spotify, Tidal, etc) do you get a high enough sound volume in your listening room?
 

Rc Lobarniz

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I guess that the the input signal for some of the sources you are using is for some reasons too low. Even in my case the level of the devices connected with toslink or coaxial digital is much lower than the analog sources. If you play the Denon using one of the various HEOS services available (TuneIn radio, Spotify, Tidal, etc) do you get a high enough sound volume in your listening room?
Answering your question definitely it is, volume is high when playing e.g. Tunein , no issues there.
I wish I knew how to increase the input signal of the toslink I have connected to the TV, I will remove the need to increase the volume on the receiver that much.
And by the way, I do not think we are deaf this unit is in my humble opinion audibly flawless, the measurement say otherwise but for me it sounds incredible, money for value is unbeatable.
I won't change it until is broken and unrepairable.
 

SoundsGood64

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First post here at ASR. I’ve been enjoying several reviews & discussions here, including this interesting one for DRA-800H. amirm tested the DRA-800H using the Zone 2 Pre-Out, which is downstream of the 7-in/3-out matrix switch. This switch can be seen in the analog and digital block diagram attached to post #117


Inputs into that 7-in/3-out matrix switch include the analog outputs from the following dacs: 1) Main zone dac AKM4458, 2) the “Network / Zone 2” DAC PCM5100A, and 3) “Downmix” DAC PCM5100A.

The label “Zone 2 Pre-out” on the outside case is suggestive but not proof that this pre-out is receiving the analog output from the “Network /Zone 2” DAC PCM5100A. The presence of the switch raises the possibility that this pre-out can be fed from any of the 3 DACS depending on the configuration. amirm stated in post #1 that he set the DRA-800H such that Zone 2 would “mirror the main zone output”.

https://www.audiosciencereview.com/.../denon-dra-800h-review-stereo-receiver.26743/

Perhaps amirm can state what he set on the DRA-800H (ie All Zone Stereo? Another setting?) and based on this setting choice members can comment on which of these DACs was likely feeding the Zone 2 Pre-out in his testing procedure. My guess is that it was probably the Network / Zone 2 DAC PCM5100A, but this is just the simplest explanation based on the probable settings and “Zone 2 Pre-out” label.

This discussion also raised an issue that I’ve been wondering about, which is the purpose of the “non-zone” DACs in many AV receivers. Consider the AVR-X6400H, similar to many receivers reviewed at ASR. In addition to a Main Zone AKM4458 DAC, the AVR-X6400H has a dedicated PCM5100 DAC for Zone 2, and another dedicated PCM5100 DAC for Zone 3. That each zone has a corresponding and dedicated DAC stack (I write “DAC stack” because the main zone actually consists of two AKM4458 chips).

For the AVR-X6400H, any three of these DACs can receive a digital input such as from optical or coax, but also from the Network module. The signal pathway from the Network Module can be observed in the AVR-X6400H service manual going to the respective DAC stacks for the Main Zone (p162), Zone 2 (p165, attached here), and Zone 3 (p.167). That the Network Module can send digital signal to the Main Zone DAC is consistent with statements from Denon posted elsewhere at ASR and also the nearly identical SINAD for AVR-X4700H using a 1khz zone via Heos (network) or coaxial input.


So the Network Module can send digital signal to any one of the 3 DACs serving Zones: Main, 2, and 3. Yet, many AV receivers, including the AVR-X6400H and the DRA-800H have an additional ‘network DAC’. So what is the purpose of this specific ‘network DAC’?

The DRA-800H also has a “downmix DAC PCM5100A” and what is the purpose of this? I’m not sure what the “downmix” could be because the DRA-800H HDMI input accepts only 2ch PCM (p 175 user manual), and not the usual (in AV receivers) 5.1 or 7.1 ch, and not DSD, Dolby True HD or DTS Master Audio.

The AVR-X6400H has 3 zones, each with its corresponding dedicated DAC-stack, yet there is an additional (4th) ‘network dac’. Likewise, the DRA-800H has just 2 zones and three DAC stacks. For ‘n’ zones, there seems to be n + 1 DAC stacks. There must be a reason for this, but it is unknown to me.

In summary, questions I’ve posed here:

1. Which of the three DACs in the DRA-800H was feeding the Zone 2 pre-out for Amir’s testing procedure, the Main Zone AK4458, the Network /Zone 2 PCM5100A, or the “Downmix PCM5100A” ?

2. What is the purpose of having a separate “Network dac” in many AV receivers including the DRA-800H, given that there is a dedicated DAC for each Zone which can process digital signal of network source? Further, why is there an additional ‘downmix dac’ for the DRA-800H? The answer may or may not be related to the observation that for n zones there are n+1 DAC stacks in these receivers.

3. Does anyone have any evidence, such as from a Service Manual or other source including physical testing, of whether for the DRA-800H the network digital signal (HEOS) is sent to the Main Zone AKM4458 DAC, just as it does for the mainline Denon receivers such as AVR-X6400H and AVR-X4700H?

Hope this generates further discussion. Thanks!
 

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SoundsGood64

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@amirm, of the typical measurements you do when assessing a DAC using a digital input and pre-out output, such as on an AVR, are there any that would give a unique ‘fingerprint’ or ‘signature’ of a particular model of DAC chip or even an individual DAC chip?

The reason I ask is because @ttt, @peng, @mike7877, and others on this review thread raised the possibility that when you did your measurements from the DRA-800H Zone 2 Pre-out, it is possible that you were measuring downstream of a (Network/Zone 2 or Downmix) PCM5100A DAC chip, rather than the main zone AKM4458, which has the higher spec. If such a signature exists for at least one of your measurement types, that signature could be used to distinguish which DAC chip is upstream of the Zone 2 pre-out with particular settings, as I suspect the signature would still be present whether you measure from the pre-out or the speaker terminals. This would aid in testing the DRA-800H which doesn’t have main-zone pre-out.

There’s at least a possibility for the DRA-800H that one can switch between the AKM4458 and PCM5100A for the Zone2 Pre-out, depending on a particular setting. There are two ways I know of for the Main Zone and Zone 2 to play the same source. One is to use the “Zone 2 Source” Button on the front panel (second button from left). This button cycles through the possible sources, with the first option being “Source”, which if chosen mirrors in the Zone 2 what is being played in the Main Zone. This first option almost certainly utilizes the “Downmix DAC PCM5100A” upstream of the Zone 2 pre-out (distinct from the Network/Zone 2 DAC also PCM5100A). This is based on my review of the service manual for AVR-X2600H which shares the same Audio PLD and DAC stack, as the DRA-800H, from the block diagrams provided by @bloodshoteyed. So if you used this first option when measuring, it is very likely that indeed, you were testing the PCM5100A DAC, as previously suggested by others on this thread. The second method is to use the “Option” button on the remote control to turn on “All Zone Stereo”. There could be a hint in the AVR-X2600H and DRA-800H block diagrams as to how “All Zone Stereo” is implemented, perhaps others who’ve used the DRA-800H ( @GiBo61, @Rc Lobarniz , @eddantes , @Jakke ) might know for sure. The analog block diagrams show that for the Front L and R the analog output from the AK4458 splits into two paths. One path goes to the amp and speakers. The other path goes to the 7in/3out matrix switch where it could be shunted to the Zone 2 pre out. So I’m guessing that when one turns on “All Zone Stereo” one is telling that 7in/3out switch to direct the AKM4458 Front L and R analog output to Zone 2. It’s a reasonable possibility.

Hence, would it make sense to retest the DRA-800H from the Zone 2 pre-out comparing the first (“Zone 2 Source set to Source”) or second (“All Zone Stereo”) method, also leveraging the potential for a DAC fingerprint to identify the DAC model in use? Maybe it would be the same result, but maybe not! Unsure if amirm, you still have the DRA-800H but if so perhaps worth a try depending on what settings you used to generate your report.
 

peng

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@amirm, of the typical measurements you do when assessing a DAC using a digital input and pre-out output, such as on an AVR, are there any that would give a unique ‘fingerprint’ or ‘signature’ of a particular model of DAC chip or even an individual DAC chip?

The reason I ask is because @ttt, @peng, @mike7877, and others on this review thread raised the possibility that when you did your measurements from the DRA-800H Zone 2 Pre-out, it is possible that you were measuring downstream of a (Network/Zone 2 or Downmix) PCM5100A DAC chip, rather than the main zone AKM4458, which has the higher spec.

If you look at the results of using analog input in pure direct, the results are still only 77 to 78 dB so in that case we have to assume the power amp section is responsible for the poor results and no DAC can help this receiver to do better.

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peng

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Hence, would it make sense to retest the DRA-800H from the Zone 2 pre-out comparing the first (“Zone 2 Source set to Source”) or second (“All Zone Stereo”) method, also leveraging the potential for a DAC fingerprint to identify the DAC model in use? Maybe it would be the same result, but maybe not! Unsure if amirm, you still have the DRA-800H but if so perhaps worth a try depending on what settings you used to generate your report.

I am not sure if I understand what you are suggesting. The problem is, Amir cannot access the main zone pre out because there is none.

There is one thing you can do with this amp to at least take advantage of its nice preamp, that is to use the zone2 pre out to drive an external amp. If Amir had use analog input, direct mode and measured the zone2 pre out, he would most likely be able to get 95 to 100 dB SINAD.

That also mean you can use an external DAC, or CD player with the analog input and use external amp via the zone2 pre out for two channel music listening. That is probably not useful for most users, but it does allow one to avoid the PCM5101 when analog inputs and direct mode are used. Even a cheap DAC will get you much higher SINAD than 86 dB. That's of course on paper only, there may or may not be audible difference as that always depend..
 

SoundsGood64

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Hi @peng, very much appreciate your interest and expertise on this specific DRA-800H thread and the ASR forum overall. A real pleasure to read your posts. Using analog input amirm measured SINAD at 77-78 dB for amp, certainly is not at the top in comparison. I agree completely with what you are saying—it makes sense-- that this 78dB is the ceiling of what the DRA-800H is capable of at the amp; any digital input will cause a further decline due to the additional contribution of THD+N from the DAC. Indeed, for the DRA-800H, we observe with digital input (HDMI or coax, not sure which due to notation but not too impt) SINAD down to 62dB for the amp. I wonder if down in 60-70dB range if the problem is audible? In any case, I believe this steep decline from 78 to 62dB is due to the relatively low SINAD of 85-86 dB for the DAC (measured from Zone 2 pre out). Do you agree? I really am a newbie here so just want to make sure I understand.

"I am not sure if I understand what you are suggesting. The problem is, Amir cannot access the main zone pre out because there is none."

Yes, I definitely acknowledge that there is no Main Zone pre-out on the DRA-800H, and so therefore amirm was not able to take a measurement in that preferred way. Instead, I was suggesting (in post #135) the possibility that the AKM4458 (and not the lower spec PCM5100A) DAC analog output feeds the Zone 2 pre-out if “All Zone Stereo” is selected after pressing the “Option” button on the remote. This concept is based on an analysis of the analog and digital block diagram which shows an electrical connection-- via the 7in/3out matrix switch--between the AKM4458 analog out and the Zone2 pre-out. Just a possibility. As you say, one could utilize the Zone2 pre-out with an external amp, and if that Zone 2 pre-out were being driven upstream by the analog output from a higher performing AKM4458 that hadn’t been measured previously, that could certainly be of interest. If @amirm still has the DRA-800H is it such a crazy idea to do the measurement for objectivity sake, as well as the real potential for gaining practical knowledge?
 

peng

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Hi @peng, very much appreciate your interest and expertise on this specific DRA-800H thread and the ASR forum overall. A real pleasure to read your posts. Using analog input amirm measured SINAD at 77-78 dB for amp, certainly is not at the top in comparison. I agree completely with what you are saying—it makes sense-- that this 78dB is the ceiling of what the DRA-800H is capable of at the amp; any digital input will cause a further decline due to the additional contribution of THD+N from the DAC. Indeed, for the DRA-800H, we observe with digital input (HDMI or coax, not sure which due to notation but not too impt) SINAD down to 62dB for the amp. I wonder if down in 60-70dB range if the problem is audible? In any case, I believe this steep decline from 78 to 62dB is due to the relatively low SINAD of 85-86 dB for the DAC (measured from Zone 2 pre out). Do you agree? I really am a newbie here so just want to make sure I understand.

"I am not sure if I understand what you are suggesting. The problem is, Amir cannot access the main zone pre out because there is none."

Yes, I definitely acknowledge that there is no Main Zone pre-out on the DRA-800H, and so therefore amirm was not able to take a measurement in that preferred way. Instead, I was suggesting (in post #135) the possibility that the AKM4458 (and not the lower spec PCM5100A) DAC analog output feeds the Zone 2 pre-out if “All Zone Stereo” is selected after pressing the “Option” button on the remote. This concept is based on an analysis of the analog and digital block diagram which shows an electrical connection-- via the 7in/3out matrix switch--between the AKM4458 analog out and the Zone2 pre-out. Just a possibility. As you say, one could utilize the Zone2 pre-out with an external amp, and if that Zone 2 pre-out were being driven upstream by the analog output from a higher performing AKM4458 that hadn’t been measured previously, that could certainly be of interest. If @amirm still has the DRA-800H is it such a crazy idea to do the measurement for objectivity sake, as well as the real potential for gaining practical knowledge?

I am not sure if there is a way if the AK4458 could be routed to tbe z2 preout but will take another look. I hope you are right.
 

SoundsGood64

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Hi @peng, Thanks for taking a look.
Referring to the DRA-800H block diagram supplied by @bloodshoteyed.
The AKM4458 analog out L & R goes to the InA/B6 of the 7in/3out matrix switch. The Zone2 would correspond to the OUTA3 and OUTB3 for L and R respectively on the output side of the same matrix switch. For there to be a connection, the user would have to somehow set a connection between InA/B6 and OUT3. My hypothesis is that this connection is set with "All Zone Stereo" but I do not know for sure that this is how to establish the connection. In any case, "All Zone Stereo" means that Zone 2 plays the same source as Main Zone.

The other way for Zone 2 to play the same source as Main Zone is to use the "Zone 2 SOURCE" button on the front panel (button second from left). This button allows cycling though the various sources such as CD, blu-ray, etc. But if you select "Source" this causes Zone 2 to play the same music as Main Zone. Based on the service manual for AVR-S950H/X2600H (similar to DRA-800H with same PLD, DAC stack etc), when set in this way, digital signal goes through the "Downmix DAC PCM5100A" and the resulting analog is routed to Zone 2 via a 7in/3out switch. It is possible that this was the setting for the original measurement which no one was excited about.

Let us know what you think and much appreciate your consideration on this!
 
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