Denon DRA-800H Review (Stereo Receiver)

[peng]

I only checked the digital input Coaxial. Unfortunately PCM5100A used to output in ZONE 2. SINAD 93-94 dB. The Best SINAD in ZONE 2 is 100-102 dB from analog input.

You are really lucky to get 93-94 dB based on the specs of the PCM5100A IC itself.

 

[User_22]

One way to play the same digital source in both Main Zone and Zone 2 is to do what User_22 did:
DIGITAL AUDIO IN: Coaxial
MAIN ZONE: CD
ZONE 2 Source: Source, Signal via PCM5100A, SINAD -94dB

In other words, by selecting the Zone 2 source as "Source" the same digital audio signal (in this case CD via coaxial) can be played in both the Main Zone (presumably by the Main Zone DAC, PCM1690 in the revised model User_22 has), and in Zone 2 (via PCM5100A).

There is different way to play the same digital source in both Main Zone and Zone 2. While playing a source (such as CD via a coaxial digital audio in) in the Main Zone, a person can press the OPTION button on the remote control and select "All Zone Stereo" from the onscreen menu. Doing this causes the CD audio to be played in both the Main Zone and Zone 2. The manual states that the sound mode for All Zone Stereo is restricted to STEREO only (DIRECT not allowed).

When playing a digital audio source in both the Main Zone and Zone 2 using All Zone Stereo, it would be interesting to know which DAC chip, PCM1690 or PCM5100A, is upstream of the Zone2 pre-out, and further, what the measurements, such as SINAD, are obtained from the Zone 2 pre-out. On the one hand, the SINAD might be better if the (higher spec) PCM1690 is being used rather than the (lower spec) PCM5100A. But on the other hand, the SINAD might be worse because of the required use of STEREO rather than DIRECT sound mode. The block diagram shows two physically possible pathways for the analog output of the PCM1690 (or AKM4458 as the original version of DRA-800H) connecting to the Zone 2 pre-out, and that is the key motivation for raising this question.

I hope User_22 also finds this an interesting question, and would be willing to test, measure, and report the findings when using All Zone Stereo to produce output at the Zone 2 pre-out.

All Zone Stereo There is no option for me. There is "Video Select", "Tone", "Balance" in sound mode STEREO. In other sound modes is "Video Select" only.

 

[GiBo61]

I only checked the digital input Coaxial. Unfortunately PCM5100A used to output in ZONE 2. SINAD 93-94 dB. The Best SINAD in ZONE 2 is 100-102 dB from analog input.

Both SINAD values you measure are much better than the ones obtained by Amir (I'm still wondering why...). If this is the reality we cannot complain about it, at least we have the possibility to use Zone2 output as a pre-out with a clean enough signal for an external power amplifier. I'm now wondering in the unit tested by Amir was somehow faulty and also the internal amplifier section has better measurements than the ones he published.

 

[peng]

Both SINAD values you measure are much better than the ones obtained by Amir (I'm still wondering why...). If this is the reality we cannot complain about it, at least we have the possibility to use Zone2 output as a pre-out with a clean enough signal for an external power amplifier. I'm now wondering in the unit tested by Amir was somehow faulty and also the internal amplifier section has better measurements than the ones he published.

I seem to remember @SoundsGood64 (if I remember right that it was him) posted some signal path block diagrams before, you can look them up and see if under certain conditions, zone 2 pre outs are not connected to the internal power amp. In that case it would explain the much higher SINAD.

 

[User_22]

Both SINAD values you measure are much better than the ones obtained by Amir (I'm still wondering why...). If this is the reality we cannot complain about it, at least we have the possibility to use Zone2 output as a pre-out with a clean enough signal for an external power amplifier. I'm now wondering in the unit tested by Amir was somehow faulty and also the internal amplifier section has better measurements than the ones he published.

Amir wrote the amp is very hot. Thermal Protection works and the user is unaware of it. The amplifier works in ECO mode. Sound quality is poorer. The amplifier needs to be turned off and on. I had this situation. Technically, this is done by reducing the supply voltage from + -60V to + -24V.

 

[SoundsGood64]

All Zone Stereo There is no option for me. There is "Video Select", "Tone", "Balance" in sound mode STEREO. In other sound modes is "Video Select" only.

When pressing the OPTION button on remote, there is no All Zone Stereo for User_22 to select. This feature is described in the DRA-800H user manual. I can only think of two possibilities right now to explain the absence of this feature, and will list others if they come to mind.

Possibility 1) User_22 has a revised DRA-800H which does not have the All Zone Stereo feature, or the firmware update that User_22 performed recently removed the feature.
Possibility 2) HDMI Audio Out is set to "TV". From remote, press SETUP. Then, Video-->HDMI Setup-->HDMI Audio Out. Select "Stereo Receiver" rather than "TV" to enable the All Zone Stereo feature.

 

[SoundsGood64]

You are really lucky to get 93-94 dB based on the specs of the PCM5100A IC itself.

User_22 confirmed that the PCM5100A was upstream of the Zone2 Pre-out using a method (see User_22's earlier post) that physically identified the specific IC in the board using an electrical contact with pin 6 or pin 7 (output pins) in the IC. This was under the specific condition of the Zone 2 source selection as "Source".

"Lucky" may very well be the correct term here. I wonder if there is some kind of statistical distribution, perhaps a normal distribution, of THD+N for these DAC ICs and the spec sheet reports the average, which for PCM5100A is -90dB. Perhaps User_22 did indeed get *Lucky* by getting a unit on the right tail of that distribution.

 

[User_22]

You are really lucky to get 93-94 dB based on the specs of the PCM5100A IC itself.

Thank you very much for the question. I decided to check again.

The result surprised me. The amplifier housing is still open. I shorted the chip PCM5100A pin 6 to ground. The signal at the ZONE 2 output has not changed! The signal to ZONE 2 went through chip PCM1690.
My DRA-800H is connected to the internet all the time. Apparently the firmware has been updated. If so, thanks to the DENON team. I checked Setup / General / Information / Firmware. Version: 5300-3000-6003-1000. Maybe you have other versions?

Congratulations to all for purchasing a good network receiver as a signal source.

 

[SoundsGood64]

Thank you very much for the question. I decided to check again.

The result surprised me. The amplifier housing is still open. I shorted the chip PCM5100A pin 6 to ground. The signal at the ZONE 2 output has not changed! The signal to ZONE 2 went through chip PCM1690.
My DRA-800H is connected to the internet all the time. Apparently the firmware has been updated. If so, thanks to the DENON team. I checked Setup / General / Information / Firmware. Version: 5300-3000-6003-1000. Maybe you have other versions?View attachment 177239

Congratulations to all for purchasing a good network receiver as a signal source.

@User_22, thanks for sharing and repeating these valuable measurements. Did you confirm that PCM1690 was upstream of the Zone 2 pre-out by shorting the PCM1690 analog output pin and then detecting the drop in signal at the Z2 pre-out? If so, I wonder why in one case it was PCM5100A and the other case it was PCM1690. Any ideas? Power cycle allowing the switch maybe?

Also, if it was the PCM1690 here, the IC spec for THD+N is -94dB and here you are measuring -100 dB. The IC spec for THD+N for PCM5100A is -90dB, and since you also measured a very good SINAD number for PCM5100A in situ of -94dB, is it possible that you have a systematic characteristic in your setup that consistently produces lower (more negative, better) SINAD?

 

[peng]

Thank you very much for the question. I decided to check again.

The result surprised me. The amplifier housing is still open. I shorted the chip PCM5100A pin 6 to ground. The signal at the ZONE 2 output has not changed! The signal to ZONE 2 went through chip PCM1690.
My DRA-800H is connected to the internet all the time. Apparently the firmware has been updated. If so, thanks to the DENON team. I checked Setup / General / Information / Firmware. Version: 5300-3000-6003-1000. Maybe you have other versions?View attachment 177239

Congratulations to all for purchasing a good network receiver as a signal source.

So now you are getting 98-99 dB at pre out voltage up to 5.62-5.64 V assuming your 0 dBV is 1 V?

I don't have one, but it probably is a decent network receiver if used as a preamp/dac via zone2. The power amp performance is ok but not that good, just comparable to that of the old entry level AVR-X2200W.

​

 

[GiBo61]

Amir wrote the amp is very hot. Thermal Protection works and the user is unaware of it. The amplifier works in ECO mode. Sound quality is poorer. The amplifier needs to be turned off and on. I had this situation. Technically, this is done by reducing the supply voltage from + -60V to + -24V.

I never had this problem. I guess I never stressed my DRA-800H enough.

 

[User_22]

So now you are getting 98-99 dB at pre out voltage up to 5.62-5.64 V assuming your 0 dBV is 1 V?

Not right. Amplitude is dBV rms. 5.62-5.64 dBV or 1,91- 1,914 Vrms. dBV to V Calkulator

 

[peng]

Not right. Amplitude is dBV rms. 5.62-5.64 dBV or 1,91- 1,914 Vrms. dBV to V Calkulator

Thank you, I don't know why I typed 5.62+5.64 V, I don't even need that calculator to know that it should be about 1.9 V.

Yep, so at 1.9 V you are getting 98-99 dB SINAD, that is fantastic, just look too good to be true but being differentially connected, that is possible for the PCM1690. Too bad Denon/Marantz failed to put in some decent power amps.

 

[SoundsGood64]

The truth is there is something I don’t like. Amplifier channel on the left. Its distortions are even 17 dB higher than the right channel. I still don't know where the problem is?

User_22 has now found that the SINAD on the L&R Z2 pre-out is about -100 dB on both channels using a digital coax input in direct mode, and has attributed this to an upstream PCM1690 when Z2 source is set to source. Yet, at the (Main Zone) speaker terminals the L amp channel had a 17dB distortion higher than the R amp channel. We know the problem can't be the PCM1690 DAC or the analog connection immediately output from the DAC due to the updated Z2 pre-out measurements User_22 posted earlier today. So the distortion might be arising from the L amp or the L speaker relay. The speaker relay can be easily tested because the DRA-800H has an A speaker relay and a B speaker relay. User_22 can simply use the other speaker relay and see if the L sided 17dB distortion persists. If this distortion persists, then the problem is likely related to the L amp. If the 17dB distortion goes away, then the distortion was arising from the A speaker relay (if that's the relay that was used in the initial measurement). There's a reasonable chance that it is the speaker relay. Speaker relays have moving parts that are subject to corrosion on the electrical contacts. Worth a try at least.

 

[User_22]

User_22 has now found that the SINAD on the L&R Z2 pre-out is about -100 dB on both channels using a digital coax input in direct mode, and has attributed this to an upstream PCM1690 when Z2 source is set to source. Yet, at the (Main Zone) speaker terminals the L amp channel had a 17dB distortion higher than the R amp channel. We know the problem can't be the PCM1690 DAC or the analog connection immediately output from the DAC due to the updated Z2 pre-out measurements User_22 posted earlier today. So the distortion might be arising from the L amp or the L speaker relay. The speaker relay can be easily tested because the DRA-800H has an A speaker relay and a B speaker relay. User_22 can simply use the other speaker relay and see if the L sided 17dB distortion persists. If this distortion persists, then the problem is likely related to the L amp. If the 17dB distortion goes away, then the distortion was arising from the A speaker relay (if that's the relay that was used in the initial measurement). There's a reasonable chance that it is the speaker relay. Speaker relays have moving parts that are subject to corrosion on the electrical contacts. Worth a try at least.

Thanks for the suggestion. Speaker relays checked. Is good. The problem is final transistors. In ECO mode the difference is smaller, about 10 dB. There are actually transistors other than those written on the PCB.

 

[peng]

Thanks for the suggestion. Speaker relays checked. Is good. The problem is final transistors. In ECO mode the difference is smaller, about 10 dB. There are actually transistors other than those written on the PCB.

I also think it is the power amp. Relay may add noise but from the graph it seems clear the culprit is the 3rd harmonic spike. How about at higher output, such as at 20 V-25 V? Also, did anything change if you let the amp warm up first?

It could be the left channel's bias not adjusted correctly, at the factory I mean.

 

[User_22]

I also think it is the power amp. Relay may add noise but from the graph it seems clear the culprit is the 3rd harmonic spike. How about at higher output, such as at 20 V-25 V? Also, did anything change if you let the amp warm up first?

It could be the left channel's bias not adjusted correctly, at the factory I mean.

Bias its OK! According to the service manual 36 mA. I did 45 mA, didn't do better. ECO mode only 11 mA. Normally outputs 150W without any problems. Amplifier cold, 8 ohms is hot. At output 5W, the amplifier is hot and 8 ohms is cold. One of the transistors has low gain. The result is little feedback for a good SINAD.

 

[ttt]

Bias its OK! According to the service manual 36 mA. I did 45 mA, didn't do better. ECO mode only 11 mA. Normally outputs 150W without any problems. Amplifier cold, 8 ohms is hot. At output 5W, the amplifier is hot and 8 ohms is cold. One of the transistors has low gain. The result is little feedback for a good SINAD.

Can you please measure the poweramp's THD+N?

 

[GiBo61]

Can you please measure the poweramp's THD+N?

Yes, that would be great!

 

[User_22]

Can you please measure the poweramp's THD+N?

Post 202, shown power at a load of 8 ohms 5 W. At a load of 4 ohms it goes over 150 W. In ECO mode, about 40 W.