Purchase advice needed: AVR and stereo power amp

[voodooless]

4K/60 is absolutely fine for me, as long as all HDR modes are supported.
I found in the original documentation, that the X3600H does not support HDR10+ passthrough, but it does support Dolby Vision.
Technically, that seems strange to me, since both do the same thing over HDR10 non-plus... Dynamic metadata.

I was wondering if the X3600H got a firmware upgrade to support HDR10+ passthrough or if it maybe just does it?
Do you know or is there a dedicated X3600H thread I can ask in?
Is Amir's review thread maybe a good place to ask this?

Denon AVR-X3600H AV Receiver Review

This is a review and detailed measurements of the Denon AVR-X3600H 9.2 channel AVR. It was purchased new by a kind member who drop shipped it to me. It costs US $1,099. From outside the AVR-X3600H seems like any other AVR: But the controls feel a lot better than some other AVRs. The...

www.audiosciencereview.com

I have an aging 7 year old Marantz, and it does 4k/60 and Dolby Vision just fine. It also does HDR10 via Amazon Prime. Technically that should be HDR10+, but my TV doesn't support that, so it does without the "+".

 

[ZolaIII]

10+ is HDR10 + metadata (croma +luma...) and a good way to make non HDR broadcast (REC 709) HDR like ( EOTF: SMPTE ST 2084) so useful in short. Didn't see Denon among adopters but best place to ask would be a owners thread. Don't know if even now last year's models would have Dolby Vision hi FPS updates but that is how it goes with standards.

 

[jd17]

Some feedback from my side, it's been a while.

After searching for months, I was finally able to get a used Denon AVR-X3600H.
I have had it for some very busy weeks now, so my conclusion is not final.
Unfortunately, I did not have the time to do some measurements yet.

First of all, the Audyssey implementation is obviously better / flawless.
I no longer have the problems I described with my sub.
After running Audyssey, the Denon preselects a much more realistic crossover (40Hz), which I raised to 80Hz.
I would have liked 70Hz, because that is the sweetspot according to my measurements, but Denon only offers 20Hz steps in the crossovers.

Either way, the sound with sub is very good, far from the mess that the XT32 implementation in my old Onkyo threw at me over and over again.
Once I have more time, I will of course do the according measurements.

I also want to run Audyssey without sub to see if the Denon implementation would harm my speakers too by raising below 30Hz.
Lots of tests still to do.

The MultEQ Editor app works quite well and offers plenty of fine-tuning capabilities.


Even though I am quite happy with the sound, I now want to see if my speakers can do a bit more, so I did just order the Audiophonics Hypex power amp.
Looking forward to testing that too!
I am not expecting miracles, but I think I am happy to keep it just for the peace of mind.

 

[jd17]

I finally had the time for measurements and fine-tuning.
46 measurements in a few days... is that normal?

The Denon AVR-X3600H is a very fine AVR and it's Audyssey implementation is flawless.
None of the issues occur that I faced with my old Onkyo.

Sub:
If you remember - whenever I had the sub embedded in the setup (at any position), the Onkyo did the following:
- set the crossover to 120-150Hz
- raised the sub level massively
- made the fronts unusable below 120Hz

Onkyo TX-NR818:

Red: no Audyssey, best manual sub result at the time, 50Hz crossover, 180° phase
Blue: "best" Audyssey result at 80Hz crossover - 36Hz is 12dB above the bass level at 150Hz!
Teal: Audyssey Fronts without sub, based on measurement with sub - no crossover, fronts in full range - crippled!

Before I show you similar measurements with the Denon, I have to mention that the sub is at a different position and I never saw the need to measure the fronts without a crossover... simply because the Denon makes no mistakes in that regard.
The different sub position however did not change anything on the Onkyo either, it produced the same crap.

Denon AVR-X3600H:

Red: no Audyssey, best manual sub result now (most 100Hz gain), 80Hz crossover, 135° phase
Blue: best Audyssey result at 80Hz crossover - 80-150Hz well covered, trimmed peaks at 72Hz and 33Hz.
Teal: Audyssey Fronts without sub, based on measurement with sub - 80Hz crossover - AVR did exactly as it should.

Beacuse the measurements were based on different runs, I was not able to fully overlay the levels perfectly, but I think it still shows what is going on.

Unfortunately, the subwoofer (a 9 year old SVS SB12-NSD, predecessor of the SB2000) is now starting to "go".
It's amp module is broken, which results in it producing random noises.
However, the measurements are unaffected, I made sure of that.
Because of this defect and that fact that I wanted to test 2.0 anyhow, I am showing you my tuning for the Fronts without sub...


2.0 - no sub:
If you remember - the Audyssey correction of my Fronts without sub was great, but it endangered the speakers massively.

Onkyo TX-NR818:

Red: no Audyssey, fronts in pure direct mode
Blue: Audyssey, it raised 25Hz by 9dB! The speakers roll off naturallyin the 40Hz range and the raise is even much below the 33Hz room mode!

My idea was to use the Audyssey MultEQ Editor App to introduce a subsonic filter directly below the 33Hz mode, in order to protect the speakers' bass drivers.
As it turns out, that would not even be necessary....

Denon AVR-X3600H:

Yellow: no Audyssey, fronts in pure direct mode
Green: Audyssey flat, no App tuning - Audyssey respects the natural rolloffs, especially below the 33Hz mode.

In this measurement, the sub is still placed at the same position as before, but turned off.
Comparing the results, you can see that the 33Hz mode is much more pronounced, since the sub chassis is passively oscillating, amplifying the speakers' response a little bit.
Even with that extra "support", the Denon AVR still respects the rolloffs.

Next step will be removing the sub from the room and doing new measurements and tuning.
However, I am seriously considering keeping it as a passive booster, if I achieve a better result with it there.
Altough I do understand that in "passive mode", the sub must surely introduce delay and subsequently, increased reverberation.

I am showing an absolutely flat result from Audyssey above.
It is fine, but I made the following adjustments to improve the sound - which is now better than ever:

(Mind that I adjusted the Y axis range to better illustrate the adjustments. It looks exaggerated compared to the previous screenshots...)

Adjustments:
- Subsonic below 33Hz (better safe than sorry)
- Raised 33Hz to utilize the natural room gain
- Raised 50-150Hz as peak (because I like. )
- Introduced a light "house curve" between 100Hz and 10kHz
- Limited Audyssey correction to 12kHz, because I like the little extra "air", natural rolloff in the room is enough

The result sounds better than anything I have heard from my speakers before!
Very happy.
If it gets even better without the "passive sub" - brilliant!

Comparing the best 2.1 vs. the best 2.0 results, I actually think I might even be better off without the sub:

- Below 30Hz, there is nothing without the sub. So clearly, advantage sub.
- 30-47Hz is better with sub, however not by a large margin.
- 48-66Hz is clearly better without sub and I believe for music, that range is much more important than the deepest bass...

What do you guys think?

Last but not least, I do have the Audiophonics LPA-S500NC now.
While craftsmanship, terminals and all of that are absolutely perfect, I hear no difference whatsoever with this power amp added.
To make sure it was not simply my subjective limits, I measured the maximum power draw of the amp.
It peaked at 29W when I played really bass-heavy songs very loudly.
Obviously, my speakers are not very power hungry and the internal power amps of the Denon AVR would have sufficed.

I am however keeping the power amp for two reasons:
- Peace of mind that I have 95+dB of SINAD even at the highest levels.
- Maybe I will upgrade my speakers at some point in time...

If anyone really reads all of this - kudos and thank you!

 

[peng]

Thank you, that really helps a lot!


That is great to hear, thank you.

I was worried that the performance of these great power amps somehow would not translate.
Certainly, I would never drive 2,35V - but I was rather concerned the AVRs would limit where it counts if their "range" is capped...?
I do not know if that makes sense but I read about the pre-out sensitivity in an older thread here, which I did not really understand.
Ahh, I found it:

Hypex NC502MP NCore Amplifier 500Wx4 compatability with AVR

I am curious if my AVR preouts have enough amps/voltage to power my future amp. my AVR is the : Integra DRX 3.4 My amp would be the : VTV AMPLIFIER Four Channel Hypex NC502MP NCore Amplifier 500Wx4 Also, could I use this cable to connect my AVR and Amp ??

www.audiosciencereview.com

By any chance, do you understand what the discussion is about?


I do not understand..?
Did the internals of the 3700 change over time in production?


Thank you! That is very kind of you to say.

The Denon avrs such as the 3600, 3700, 3800 can output 4 V before clipping. Amir typically only test up to 2 V on unbalance pre out, but he did test to above 4 V a couple times. Don't worry anout this one.

Also, Audyssey don't boost much than x dB, I forgot the limit, may be 6 to 9 max? If you search hard you will find it. So not much to worry about damaging your sub either.

You seem to like REQ/RC, so I think the 3800 may be a better choice because of the better bass management and RC options

 

[Astrozombie]

Time for a ported sub?

 

[peng]

I finally had the time for measurements and fine-tuning.
46 measurements in a few days... is that normal?

Sure, I used to do much more and still thought that's normal.

The Denon AVR-X3600H is a very fine AVR and it's Audyssey implementation is flawless.
None of the issues occur that I faced with my old Onkyo.

Sub:
If you remember - whenever I had the sub embedded in the setup (at any position), the Onkyo did the following:
- set the crossover to 120-150Hz
- raised the sub level massively
- made the fronts unusable below 120Hz

Onkyo TX-NR818:
View attachment 315856
Red: no Audyssey, best manual sub result at the time, 50Hz crossover, 180° phase
Blue: "best" Audyssey result at 80Hz crossover - 36Hz is 12dB above the bass level at 150Hz!
Teal: Audyssey Fronts without sub, based on measurement with sub - no crossover, fronts in full range - crippled!

The teal curve looks okay but the blue looks crazy, something wasn't right. Did you follow instructions to the letter? Such as disable all bass management features on the subwoofer itelf?

Before I show you similar measurements with the Denon, I have to mention that the sub is at a different position and I never saw the need to measure the fronts without a crossover... simply because the Denon makes no mistakes in that regard.
The different sub position however did not change anything on the Onkyo either, it produced the same crap.

Denon AVR-X3600H:
View attachment 315865
Red: no Audyssey, best manual sub result now (most 100Hz gain), 80Hz crossover, 135° phase
Blue: best Audyssey result at 80Hz crossover - 80-150Hz well covered, trimmed peaks at 72Hz and 33Hz.
Teal: Audyssey Fronts without sub, based on measurement with sub - 80Hz crossover - AVR did exactly as it should.

Beacuse the measurements were based on different runs, I was not able to fully overlay the levels perfectly, but I think it still shows what is going on.

Unfortunately, the subwoofer (a 9 year old SVS SB12-NSD, predecessor of the SB2000) is now starting to "go".
It's amp module is broken, which results in it producing random noises.
However, the measurements are unaffected, I made sure of that.
Because of this defect and that fact that I wanted to test 2.0 anyhow, I am showing you my tuning for the Fronts without sub...

Now this set of curves looked quite normal.

2.0 - no sub:
If you remember - the Audyssey correction of my Fronts without sub was great, but it endangered the speakers massively.

Onkyo TX-NR818:

Red: no Audyssey, fronts in pure direct mode
Blue: Audyssey, it raised 25Hz by 9dB! The speakers roll off naturallyin the 40Hz range and the raise is even much below the 33Hz room mode!

Not sure what you meant by "it raised 25 Hz by 9 dB?? You have no way of knowing just by looking at the curve. Which speaker was the blue curve, front left, right, or left and right, with or without the sub? Regardless, that 9 dB gain in SPL was not due to 9 dB boost by Audyssey and the AVR.

My idea was to use the Audyssey MultEQ Editor App to introduce a subsonic filter directly below the 33Hz mode, in order to protect the speakers' bass drivers.
As it turns out, that would not even be necessary....

Denon AVR-X3600H:
View attachment 315871
Yellow: no Audyssey, fronts in pure direct mode
Green: Audyssey flat, no App tuning - Audyssey respects the natural rolloffs, especially below the 33Hz mode.

This one looks normal.

In this measurement, the sub is still placed at the same position as before, but turned off.
Comparing the results, you can see that the 33Hz mode is much more pronounced, since the sub chassis is passively oscillating, amplifying the speakers' response a little bit.
Even with that extra "support", the Denon AVR still respects the rolloffs.

Next step will be removing the sub from the room and doing new measurements and tuning.
However, I am seriously considering keeping it as a passive booster, if I achieve a better result with it there.
Altough I do understand that in "passive mode", the sub must surely introduce delay and subsequently, increased reverberation.

I am showing an absolutely flat result from Audyssey above.
It is fine, but I made the following adjustments to improve the sound - which is now better than ever:

(Mind that I adjusted the Y axis range to better illustrate the adjustments. It looks exaggerated compared to the previous screenshots...)

View attachment 315880
Adjustments:
- Subsonic below 33Hz (better safe than sorry)
- Raised 33Hz to utilize the natural room gain
- Raised 50-150Hz as peak (because I like. )
- Introduced a light "house curve" between 100Hz and 10kHz
- Limited Audyssey correction to 12kHz, because I like the little extra "air", natural rolloff in the room is enough

The result sounds better than anything I have heard from my speakers before!
Very happy.
If it gets even better without the "passive sub" - brilliant!

Comparing the best 2.1 vs. the best 2.0 results, I actually think I might even be better off without the sub:

View attachment 315913
- Below 30Hz, there is nothing without the sub. So clearly, advantage sub.
- 30-47Hz is better with sub, however not by a large margin.
- 48-66Hz is clearly better without sub and I believe for music, that range is much more important than the deepest bass...

What do you guys think?

No offence, but it is difficult to decipher when you jammed so many curves, questions, and your own answers, some appeared to be based on some misconceptions. Overall, I think you might have been over thinking, misunderstood how Audyssey works and perceived issues that didn't exist, or not as bad as you thought.

I would be better if you post specific curves that you have questions one, or just a few at a time.

Last but not least, I do have the Audiophonics LPA-S500NC now.
While craftsmanship, terminals and all of that are absolutely perfect, I hear no difference whatsoever with this power amp added.
To make sure it was not simply my subjective limits, I measured the maximum power draw of the amp.
It peaked at 29W when I played really bass-heavy songs very loudly.
Obviously, my speakers are not very power hungry and the internal power amps of the Denon AVR would have sufficed.

That's usually the case, though lots of people reported hearing things after adding an external amp, dac, preamp etc., I tend to ignore those reports if they didn't tell how they did their comparison listening.

I am however keeping the power amp for two reasons:
- Peace of mind that I have 95+dB of SINAD even at the highest levels.
- Maybe I will upgrade my speakers at some point in time...

If anyone really reads all of this - kudos and thank you!

You are not going to have 95 dB SINAD all the time as it depends on many things, but yes, I agree it is good to keep that amp for other reasons.
I did read the whole post, could have given me headache but I think the coffee helped.

Again, if you want to discuss potential causes/effects further, please post in a more focused fashion, i.e. quality vs quantity.

 

[jd17]

Also, Audyssey don't boost much than x dB, I forgot the limit, may be 6 to 9 max? If you search hard you will find it. So not much to worry about damaging your sub either.

I believe it is 12dB...
However, I never worried about the sub. This was about the passive mains.
A lot has happened since then...

You seem to like REQ/RC, so I think the 3800 may be a better choice because of the better bass management and RC options

Too late, but I do not regret getting the X3600H.
If I am not mistaken, "Dynamic EQ" does not work in conjunction with Dirac anyhow - and I like Dynamic EQ a lot.
Also, I have yet to see some actual proof that Dirac is truly superior to XT32.

Time for a ported sub?

I am honestly quite happy right now without sub!
If I ever get a new one though, I am open to both...
However, limited output was never a problem, not even now without the sub.

Did you follow instructions to the letter? Such as disable all bass management features on the subwoofer itelf?

I did. I have been using Audyssey in this AVR for 10 years with mostly great results...
I probably repeated these runs 50 times and tried everything I could think of...
The result was always the same - crap.

Not sure what you meant by "it raised 25 Hz by 9 dB?? You have no way of knowing just by looking at the curve. Which speaker was the blue curve, front left, right, or left and right, with or without the sub? Regardless, that 9 dB gain in SPL was not due to 9 dB boost by Audyssey and the AVR.

Both curves are the main speakers together.
Red is without Audyssey, blue is with.
What makes you think the raise is not caused by Audyssey in the Onkyo?
I did exactly the same thing with the Denon and you can see it does not raise below the 33Hz room mode.

No offence, but it is difficult to decipher when you jammed so many curves, questions, and your own answers, some appeared to be based on some misconceptions. Overall, I think you might have been over thinking, misunderstood how Audyssey works and perceived issues that didn't exist, or not as bad as you thought.

I would be better if you post specific curves that you have questions one, or just a few at a time.

None taken!
I was about to post anyhow, explaining that my assumption of the "passive sub" being responsible for the 33Hz gain was simply incorrect.
In this instance, I compared apples to oranges, unfortunately.
The boost was based on both speakers with their ports open vs. one speaker with it's ports closed.

I guess a lot of this is also me documenting what I did rather than asking for much input, sorry.

The one question I actually had was about the comparison with/without sub and how you guys would judge it...

That's usually the case, though lots of people reported hearing things after adding an external amp, dac, preamp etc., I tend to ignore those reports if they didn't tell how they did their comparison listening.

I know, I do the same.
For me it was just another indicator that most of these reports are wishful thinking.
However, I would not interject... let people be happy with their "upgrade" as long as they are not trying to "missionize".

I did read the whole post, could have given me headache but I think the coffee helped.

Thank you and apologies!

Again, if you want to discuss potential causes/effects further, please post in a more focused fashion, i.e. quality vs quantity.

Will do!

 

[peng]

I believe it is 12dB...
However, I never worried about the sub. This was about the passive mains.
A lot has happened since then...

It was 9 dB according to one of the founder, but that's many years ago, as you alluded to, things might have changed, though I did ask Audyssey about that in 2021 and was told 9 dB. Though, it is highly unlikely any of those RC software would go more than 9 dB, (I suspect Dirac probably won't go more than 6 dB (better imo, may be @Flavio could confirm the maximum for DL).

I don't know why Audyssey would allow boost to go as high as 9 dB regardless, as we all know, if it is room mode (nulls) related, boost almost would never work. Audyssey obviously knows that fact, so that 9 dB allowable maximum is likely for dips unrelated to room modes.

Audyssey MultEQ Room Correction Interview With Chris Kyriakakis

The Audioholics interview Chris Kyriakakis in order to learn the ins and outs of Audyssey's MultEQ room correction / auto-calibration system. Bass management, calibration, EQ and more.

www.audioholics.com

Chris Kyriakakis: The MultEQ algorithms can be set to apply any desirable amount of boost or cut depending on the application. For practical considerations in AVR systems, the filters are set to +9 dB max boost and –20 dB max cut.

 

[peng]

What makes you think the raise is not caused by Audyssey in the Onkyo?

In some cases, it would be difficult, or complicated to response to your good question. Having said that, in this case, I can try to explain as follows:

1) Audyssey would know if it was room mode, and so would not apply such a huge boost that is useless (and you obvious know it is useless to boost a null due to room mode).
2) Your graph showed the huge "boost" was at 25 Hz, that's well below your speaker's cut off point. Audyssey will not apply boost to frequencies below the - dB point because they know it would potentially cause damage. MultEQ X apparently allows that (cutoff mode) to be overridden by users, but I might have misunderstood their instructions guide on that topic/feature as I failed to understand they would even allow overriding such a safety feature.

 

[jd17]

Sorry, but neither is a satisfactory explanation for me...

1) Audyssey would know if it was room mode, and so would not apply such a huge boost that is useless (and you obvious know it is useless to boost a null due to room mode).

Audyssey does indeed boost dips and I even disagree that doing that is fundamentally useless, although I know that is not a popular opinion.
A good example would be what Audyssey does at 80-120Hz:

At my listening position (and close to it), that +5dB Audyssey raises between 80Hz and 120Hz is clearly beneficial.
I am aware that other regions of the room might suffer from that raise, but I do not really care.
That important range goes from inaudible to very nice at the main couch. Good enough for me.

I can even successfully enhance that boost by another 2dB in my optimized curve, as mentioned in the neverending story post...

2) Your graph showed the huge "boost" was at 25 Hz, that's well below your speaker's cut off point. Audyssey will not apply boost to frequencies below the - dB point because they know it would potentially cause damage. MultEQ X apparently allows that (cutoff mode) to be overridden by users, but I might have misunderstood their instructions guide on that topic/feature as I failed to understand they would even allow overriding such a safety feature.

I fully agree that Audyssey SHOULD not do that, and it does not do it in the newer Denon AVR.
However, I have multiple measurements confirming that the Onkyo implementation in fact did raise this dangerous frequency.
That eventually brought me to the conclusion that the Onkyo implementation is flawed.

 

[peng]

Sorry, but neither is a satisfactory explanation for me...


Audyssey does indeed boost dips and I even disagree that doing that is fundamentally useless, although I know that is not a popular opinion.
A good example would be what Audyssey does at 80-120Hz:

View attachment 317325

At my listening position (and close to it), that +5dB Audyssey raises between 80Hz and 120Hz is clearly beneficial.
I am aware that other regions of the room might suffer from that raise, but I do not really care.
That important range goes from inaudible to very nice at the main couch. Good enough for me.

I can even successfully enhance that boost by another 2dB in my optimized curve, as mentioned in the neverending story post...

Okay, then how about let me ask you the question instead, what make you think Audyssey did apply 9-10 dB boost at 25 Hz? You already agreed, that was the case with the Denon, why would it be different for the Onkyo implementation, do you think Audyssey would let Onkyo do something so drastically different?

By the way, your original/opening post said "Blue: Audyssey, it raised 25Hz by 9dB! The speakers roll off naturallyin the 40Hz range and the raise is even much below the 33Hz room mode!

That's the part I referred to when I said Audyssey wouldn't do such a useless thing.

Are you sure the conditions were the same when you were using the Onkyo, speakers, placement, furniture, etc.,/whatever? There must be another reason why you had that 9 dB boost at the time. Again, it's not likely a doing of Audyssey, more likely interaction between the speakers, the room, and/or something else not identified yet.

I fully agree that Audyssey SHOULD not do that, and it does not do it in the newer Denon AVR.
However, I have multiple measurements confirming that the Onkyo implementation in fact did raise this dangerous frequency.
That eventually brought me to the conclusion that the Onkyo implementation is flawed.

Might have been a good question for Onkyo at time time. Regardless, I would love to know how they managed to get such a boost at 25 kHz, even if you consider it "flawed".

 

[peng]

Audyssey does indeed boost dips and I even disagree that doing that is fundamentally useless, although I know that is not a popular opinion.
A good example would be what Audyssey does at 80-120Hz:

Of course, it can boost (as mentioned, up to 9 dB max), there is no disagreement there at all. Disagreement is on room mode null kind of dips. That is not the case in the example you use, except perhaps around 87-88 Hz, that could be a null, and it got almost 3 dB, that could be possible when combined with the filter effects in the time domain. When I said useless, obviously I exaggerated it to make a point, ineffective would have been a better word, though in some severe room mode dips, any boost more than attempting a couple dB would be literally useless.

 

[peng]

@jd17, I don't know if you had search for information on how Audyssey, and/or room correction systems work in general on room mode related dips. If not, you may want to try and may find things that you may find interesting. If you have already read lots of such technical articles about Audyssey and REQ/RC then great. I have done a lot of that and have accumulated tons of articles in my archive. There are tons of forum posts based on misinformation, or misconceptions.

AskAudyssey is not a bad place to start either if there specific questions.

https://ask.audyssey.com/hc/en-us

 

[jd17]

Okay, then how about let me ask you the question instead, what make you think Audyssey did apply 9-10 dB boost at 25 Hz?

My measurements confirm it.

You already agreed, that was the case with the Denon, why would it be different for the Onkyo implementation, do you think Audyssey would let Onkyo do something so drastically different?

The Onkyo is more than 10 years old and was an early adopter of MultEQ XT32.
It is surely in the realm of possibilities that the software and/or AVR implementations between then and now are different.

Are you sure the conditions were the same when you were using the Onkyo, speakers, placement, furniture, etc.,/whatever?

Yes.

AskAudyssey is not a bad place to start either if there specific questions.

Before buying the Onkyo in 2012, I have read AskAudyssey up and down.

 

[peng]

My measurements confirm it.

I agree your measurements confirmed there was a boost but we don't know how it was boosted so I guess in that case that graph left us both wondering about the cause, not the effect. To be clear, I never doubted anything about the existing of that "boost" at around 25 kHz. My point is simply that 9 dB was the maximum boost allowed, according to Audyssey at the time, and that it won't do such a boost below F3, and it is unlikely that your speaker's F3 is so low, though it is still possible in-room.

Even then, if the boost was proved to be due to Audyssey, it still would not necessarily mean it would stress the amp, because such a boost would have been mostly due to what the filter did in the time domain that allowed the room gain to work in favor, instead of in opposition. If that's the case, then the dip there was fixed without using the brute force of the amplifier.

Before buying the Onkyo in 2012, I have read AskAudyssey up and down.

I don't know what you might have missed, may be before 2012, AskAudyssey did not have much inquirey on the same or related topics.

Here is one that you might have missed and the example involved the Onkyo 818, I suggest you read all the back and forth between Igor and Audyssey (appeared to be Chris himself at the time):

https://ask.audyssey.com/hc/en-us/articles/212344723-Strange-boost-below-the-lowest-detected-frequency-of-speaker-

In that exchange, Audyssey stood the ground that there is no EQ below the roll off point, though it wasn't a brick wall, and instead was gradual.

The stopping of correction below the roll off frequency is not immediate. It is gradual to match the slope of the speaker roll off. Your graphs are quite typical and I don't see any issues with the low frequency behavior. The level calculation is not easily seen in your graphs. It requires a calculation of the perceived level of loudness (there is a psychoacoustic model involved) to appropriately weight each frequency.

In that case though, it would appear that Chris at least offer a partial explanation:

it looks like the energy below the red curve is being matched to the energy under the black curve (considering the large dip in the midbass). I don't have any other possible explanation.

In the end of that exchange, Chris concluded that:

Hi Igor,

Thanks for your comments. We will study them to understand what's going on. We have been unable to reproduce this.

Since I know very little, compared to Chris, so I am going to move on and let other knowledgeable to continue if they have something interesting to offer.

 

[jd17]

Even then, if the boost was proved to be due to Audyssey, it still would not necessarily mean it would stress the amp, because such a boost would have been mostly due to what the filter did in the time domain that allowed the room gain to work in favor, instead of in opposition. If that's the case, then the dip there was fixed without using the brute force of the amplifier.

I was never worried about stress to the amp. I was worried about stress to the speakers.

In that exchange, Audyssey stood the ground that there is no EQ below the roll off point, though it wasn't a brick wall, and instead was gradual.

The example you are linking is not relatable to my situation.
The person asking Audyssey for help is describing a situation where speakers have a crossover to the sub at 50Hz.
I was describing the speakers running in a 2.0 (or 5.0) setup with no sub, where the fronts did full range.

Since I know very little, compared to Chris, so I am going to move on and let other knowledgeable to continue if they have something interesting to offer.

There is no need to continue this discussion anyhow.
You were the only one doubting my measurements and I myself am happy with the new AVR.
I can clearly reproduce what happened and the Onkyo showed messy behaviour in not only one, but two instances (sub and full range).

 

[peng]

I was never worried about stress to the amp. I was worried about stress to the speakers.

If those boosts are not due to the amp's doing but room gain post Audyssey (that is, the effect of the FIR filters in the time domain), then that boost may not contribute to stressing speakers. That's just one scenario, in addition to the one you cited.

The example you are linking is not relatable to my situation.
The person asking Audyssey for help is describing a situation where speakers have a crossover to the sub at 50Hz.
I was describing the speakers running in a 2.0 (or 5.0) setup with no sub, where the fronts did full range.

It is related, but you seem not willing to consider other possibilities.

There is no need to continue this discussion anyhow.

Absolutely agree, I said that already but that's only because I don't feel you are receptive to my suggested reasons for that boost at all so there is no point wasting each other's time. Now you seem insistence on having you last say (just my feeling so I hope I am wrong on this). So, now I am just trying to clarify that I never doubted your measurements.

You were the only one doubting my measurements and I myself am happy with the new AVR.
I can clearly reproduce what happened and the Onkyo showed messy behaviour in not only one, but two instances (sub and full range).

I don't think that is true at all. I simply suggested the underlying reasons why your graph shows such a big boost in that particular low frequency of 25 Hz.

You are the one who posted about the seemingly inexplicable huge boost in such a low frequency (25 Hz iirc) and appeared to be asking for feedback (?), sorry if I misunderstood the purpose of that post. Unfortunately, I have since been trying my best to think about what could be the cause(s) for that boost shown on that particular graph. What make you think I doubt the measurements itself is beyond me.

Again, I only responded this time to assure you that I never doubted your measurements and in case others are interested on this thread know my position and won't be misled in anyway. I won't bother you with another post or response after this.