harman/kardon HK 3490 Stereo Receiver Review

redboat77

redboat77

Enthusiast
Here is more info about the factory that built the HK3490.... Originally the factory was in China but 6 years ago they moved to Vietnam, Vietnam has lower labor costs and when shipping product to Europe no customs duties. The original plan was also for products shipped to North America to have no customs duties under the TPP but this didn't pass under Trump.. Today a 2nd factory has been added in Vietnam, but there they build mostly smart BT and multi-media speakers. However their 1st factory still builds a wide-range audio components; integrated amplifiers for Marantz, Denon, Onkyo, Pioneer, Arcam, NAD, receivers for Anthem, Arcam, NAD, Audio Control and higher-end separate AV surround processors for JBL, Arcam and Audio Control... To me it is impressive to hear the multiple positive comments for the HK stereo receivers. We did (3) different series of HK stereo receivers starting in 1998 up to 2011, but the last HK stereo receiver series(3700) using the PCM power supply was done by the Harman product development/sourcing team based in Shenzen, China....

Just my $0.02... ;)
There was an earlier post, quoted here on the HK 3490 DAC:

8ch 24bit DAC
- 128x Oversampling
- Sampling Rate up to 192kHz
- 24bit 8 times Digital Filter
- Differential Outputs
- On-chip Switched-Capacitor Filter
- S/(N+D): 94dB
- Dynamic Range, S/N: 114dB
- Individual channel digital volume with 128 levels and 0.5dB step
- Soft mute
- De-emphasis for 32kHz, 44.1kHz, 48kHz
- Zero Detect Function

Can you provide more info on this? What AKM chip was used? Any further details on this would be greatly appreciated.
 
P

PENG

Audioholic Slumlord
Can you provide more info on this? What AKM chip was used? Any further details on this would be greatly appreciated.
It has the AK4589 that is a ADC/DAC combo chip, according to the service manual.
 
M Code

M Code

Audioholic General
There was an earlier post, quoted here on the HK 3490 DAC:

8ch 24bit DAC
- 128x Oversampling
- Sampling Rate up to 192kHz
- 24bit 8 times Digital Filter
- Differential Outputs
- On-chip Switched-Capacitor Filter
- S/(N+D): 94dB
- Dynamic Range, S/N: 114dB
- Individual channel digital volume with 128 levels and 0.5dB step
- Soft mute
- De-emphasis for 32kHz, 44.1kHz, 48kHz
- Zero Detect Function

Can you provide more info on this? What AKM chip was used? Any further details on this would be greatly appreciated.
The DAC in the HK3490 was the AKM 4384...
Here is a link..


Just my $0.02... ;)
 
P

PENG

Audioholic Slumlord
The DAC in the HK3490 was the AKM 4384...
Here is a link..


Just my $0.02... ;)
The 3490 has two DAC chips, the AK4384 is used for the XM Satellite radio only. The AK4589 is the main one that has better S/N specs, as quoted by Redboat77 earlier and the data sheet info backs that up:

AK4589
SINAD: 94 dB
S/N: 114 dB

Vs the AK4384 that you linked:
SINAD: 94 dB
DN: 106 dB

The AK4589 shown in the schematics has the same 94 dB SINAD as the AK4384 but is 8 dB better in S/N (DN) that is a significant difference but I wonder if it is only achievable for differential implementation. The schematics appeared to show HK did wire it in differential mode anyway.

HARMAN KARDON HK3490 SERVICE MANUAL Pdf Download | ManualsLib



1611760381014.png





The two channel AK4384 used for the XM radio:
1611760008046.png
 
redboat77

redboat77

Enthusiast
No need to get upset, just asking questions. I was not confused, you are the one who wrote (in your post#129):



That original statement is the source of confusion. 80 dB SNR is 80 dB SNR, it is not equivalent to 0.01% distortions.

However, you are correct that in you response post#132 to my question, you clarified that it was an assumption you made and explained why, so my apology for missing that part of your explanation though your original statement in post#129 is going to to misleading to some of us, not just me.

It would have been easier to follow if you had qualify the 0.01% with "at least.." and add +noise to "distortions", but again, I do apologize for not re-reading your following up post before responding. We both know that if it was just distortions with noise removed, then it could have been less, or more than 0.01% unless if your assumption was correct that Gene actually measured SINAD.

About your "I clearly stated why I thought it was SINAD. ", I would only say, to me that graph was clearly just for SNR that did not include harmonic distortions. Again, he even specified it was "via AES17". If @gene actually meant SINAD he would have made it clear for us readers. Regardless, since it is your assumption, I have to respect that.., and move on.
You were the only one confused. You failed to understand that the AES17 standard for SNR in the presence of a signal includes distortion and that my original assumptions and conclusions were correct and even conservative, and you raised the whole issue with a snarky remark questioning if I understood the difference between SNR and THD.
 
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P

PENG

Audioholic Slumlord
@PENG, NO you don't, Dude took a typo out of context from one of your post.
Thank you sir.. I absolutely did not mean to be snarky about it, but the way I wrote it, I could see why it was taken that way. As far as who's confused about what, I don't see a need to say anything else. Sorry there is no fight, but don't waste the pop corn, there's some new and good stuff on Netflix, can't wait to see the Snowpiercer season 2 tonight.
 
redboat77

redboat77

Enthusiast
Thank you sir.. I absolutely did not mean to be snarky about it, but the way I wrote it, I could see why it was taken that way. As far as who's confused about what, I don't see a need to say anything else. Sorry there is no fight, but don't waste the pop corn, there's some new and good stuff on Netflix, can't wait to see the Snowpiercer season 2 tonight.
My original post was a happy one about enjoying the music on the HK 3490...You brought the confusion and wasted the popcorn.
 
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G

Gmoney

Audioholic Ninja
Thank you sir.. I absolutely did not mean to be snarky about it, but the way I wrote it, I could see why it was taken that way. As far as who's confused about what, I don't see a need to say anything else. Sorry there is no fight, but don't waste the pop corn, there's some new and good stuff on Netflix, can't wait to see the Snowpiercer season 2 tonight.
PENG, wasn't trying to make fun of you two, AH members like You, Andrew and some of the other that know way more then/than :D me or others about gear, its just fun to watch you guys go at it some, like "Dark" humor so to speak. redboat77 fits right in as a AH member.
 
P

PENG

Audioholic Slumlord
I am ready to watch "Snowpiercer" S02E01 in 4K/ATMOS.

Also "American Gods" S03E03 in 4K. :D
Really, I thought you guys in the US is on S03 Snowpiercer already. I am not sure if American Gods is on the Canadian Netflix, will check shortly.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Really, I thought you guys in the US is on S03 Snowpiercer already. I am not sure if American Gods is on the Canadian Netflix, will check shortly.
Nope. We're just starting S02 for Snowpiercer.
 
P

PENG

Audioholic Slumlord
My original post was a happy one about enjoying the music on the HK 3490...You brought the confusion and wasted the popcorn.
When I accidentally tripped over this thread/topic again, I thought I should try one more time even though I said I would move on before. This is to help avoid others getting mislead by your claim that Gene actually measured SINAD, when afaic he in fact measured SNR. Again, the two are not same, though related to certain extent. SINAD is the inverse of THD+N, that clearly is not the same as SNR.

You first claimed the following in your "original post":

"Yes. I assumed the measurement I quoted actually refers to SINAD, that is to the ratio (signal)/(noise +THD). This is consistent with the AES17 standard that was quoted for this "SNR" measurement, although the standard actually includes ALL distortion, not just harmonic distortion."
(2) harman/kardon HK 3490 Stereo Receiver Review | Page 7 | Audioholics Home Theater Forums

and repeated in other posts as well such as post#129,131,133 and then 137 posting part of the AES17 standard.

You pasted a small part of the standard but not enough to show the difference between the two so I am pasting more below for those interested to see the difference.

Here's the link you provided:
STANDARDS AND (tu-berlin.de)
8.5 Total harmonic distortion and noise (THD + N)

NOTE The characteristic to be specified is the transfer characteristic and dynamic non-linearities in
the EUT. The results are indicative of anomalies in device behavior but may not be indicative of
audible performance.

Harmonic distortion and noise is the ratio of the output noise and distortion level to the output signal level.
Both levels shall include all harmonic, inharmonic and noise components. All components shall be included
because harmonics often alias above the folding frequency and often appear anywhere in the audio band.

8.5.1 Total harmonic distortion and noise versus frequency
The measurement should be conducted with a sine wave at – 1,0 dB FS and repeated with a sine wave at – 20
dB FS.
The test signal present in the output should be removed by means of a standard notch filter and the
remaining signal bandwidth limited to the upper band-edge frequency or 20 kHz, whichever is lower. The
level of the filtered signal should be measured and reported as a ratio to the unfiltered signal level. The
measurement should be repeated at each octave frequency from 20 Hz to one-half the upper band-edge
frequency. Since you mentioned "..in the presence of signal...", I included the sections that I believe are relevant to the discussion.

9 Signal-to-noise measurement

9.3 Signal-to-noise ratio or noise in the presence of signal
NOTE The characteristic to be specified is the ratio of the full-scale amplitude to the weighted r.m.s.
noise and distortion, expressed in decibels, in the presence of signal. It includes all harmonic,
inharmonic, and noise components. It is identical to a measurement of noise in the presence of signal.

The test signal for the measurement shall be a 997-Hz sine wave producing – 60 dB FS at the output of the
EUT. Any 997-Hz test signal present in the output shall be removed by means of a standard notch filter. The
remaining noise shall be filtered with the standard weighting filter. The measurement shall be limited in
bandwidth to the upper band-edge frequency or 20 kHz, whichever is lower. The resulting measurement shall
be read as dB FS and reported as dB FS CCIR-R.M.S.

Anyone who spent time to read carefully would know THD+N and SNR are defined differently. It seems that you are fixated on the words in Section 9.3 where it says "It includes all harmonic, inharmonic, and noise components...." and ignore or neglected the part "It is identical to a measurement of noise in the presence of signal."

The fact is, when you measure the noise, any harmonics included (from distortions) would be very low (I think you mentioned that too) because there is either no signal being applied, or as per the AES17 standard, at -60 dBFS level, so the amp isn't amplifying anything or just a small signal, and then when you applied the "full-scale amplitude" signal, the contribution of the distortions to the max voltage would be naturally low. With SINAD (reciprocal of THD+N), the test signal in the output is removed, so the measured distortions would matter a lot obviously.

Aside from the above, I would like to clarify my point that Gene's graph made reference to AES17, but I believe that merely reference the weighting or bandpass limit filters (if used) for the measurements would be in accordance with that standard, and it does not necessarily mean he following the Section 9 of the standard. My educated guess is that he likely follow the AP procedure as that's the instrument he used and trained on. And in this case he did mention, "no weighting".

Below is from the AP website:
Signal-to-noise Ratio (SNR), Dynamic Range, and Noise - Audio Precision (ap.com)

"In a conventional SNR measurement a device is first stimulated with a signal at full scale with its volume control set to maximum, if present. A level measurement is made to establish the maximum output reference. The stimulus tone is then removed and the inputs of the device are either terminated or shorted. The residual noise is then measured. The SNR value is then the ratio of the full scale output level of the device to the residual noise level of a device."

More about THD+N and THD - Audio Precision (ap.com)
"For THD+N Ratio, the rms level of the measured distortion plus noise (the signal with the stimulus tone removed) is divided by the rms level of the total signal. The result displayed on a bar meter or as a point on an XY sweep graph. THD+N ratio is most often stated in as a percentage or as a decibel value, where 0 dB represents the total signal. "

AP also made the point I am making here on the distortions part:
More about Signal-to-Noise Ratio and Dynamic Range - Audio Precision (ap.com)

"FOR DIGITAL CONVERTER MEASUREMENTS…
We recommend using this AES17 dynamic range measurement. It is intended specifically for ADC (analog-to-digital converter) and DAC (digital-to-analog converter) dynamic range and “noise in the presence of signal” measurements, as described in Section 9.3 of AES17. A similar method is defined in IEC61606.

This method differs from standard signal-to-noise and dynamic range measurements in that it uses a –60 dBFS stimulus during the noise measurement. This method is used for two reasons:

· In both ADCs and DACs, “idle tones” can be produced within the converter in the absence of applied signal. In the method here, a low-level tone is applied to the converter to avoid production of idle channel noise. The low-level tone is removed by a notch filter before measurement.

· In some DACs, the output of the device is switched off when there is no signal, providing an unrealistically quiet measurement. The low-level tone (again, notched out before measurement) defeats this muting mechanism.

"At –60 dBFS, the tone is so low that any distortion products created are below the noise floor."


And of course, THD+N is the reciprocal of SINAD.

It is amazing so much has to be said, when it should have been clear to anyone that THD+N (or SINAD) is not the same as SNR, if they were, people wouldn't be doing both measurements and manufacturers specs would not have included both in any case.
 
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