Strident sound with movies soundtrack

[joblain]

Hi,
I'm sitting 12 feet from my L/C/R and 7 feet from the rear. Using ati at527nc to feed my front towers (raal) and Sierra 2 for the back. All tweeter are pointing on the middle seat of a 3 seats couch. Sometimes movies soundtrack sound a little to strident in the mid/high frequency. When is set my Anthem d2v to dolby volume on cinema reference mode, the sound is much more smooth but have the impression that I'm missing the little punch in the chest from sub and lose some particular effects that I have with usually. I believe the receiver clip the dynamic from the soundtrack. I have room acoustics (GIK) on walls and ceiling all around. You have any recommendations for me to get the high level sound (80db reference) without the strident effect? Thanks

[Bruce Watson]

You have any recommendations for me to get the high level sound (80db reference) without the strident effect?

Listening in a small room (as in, a room in your house) is different than listening in an actual theater (large room). While I enjoy a theater at reference levels, I find that I can't get close to that in my listening room at home. The highest I ever go seems to be around -15 to -12 dB. If I go louder, it becomes strident and oppressive. Probably because of the rapid first reflections you get with small rooms (even treated small rooms).

For context, I'm listening to S2s (L/C/R), S1s (surrounds), and a pair of Rythmik LVX12s, held together through a Denon X4000 with Audyssey. Audyssey does a fine job of alignment and peak/null management for me. And I'm not close to clipping even at reference levels. It's not the equipment, it's the room.

[Blutarsky]

Have you had your hearing checked? There is an phenomena called recruitment.
http://www.nchearingloss.org/recruit.htm
B.

[joblain]

Exactly Bruce, - 12 or sometime - 10 is the maximum I can tolerate.

[jimb]

... but have the impression that I'm missing the little punch in the chest from sub and lose some particular effects that I have...

Have you tried mounting a woofer on your chest? In college, a few of us threatened to do that to an underclassman in our dorm who liked to play his sound system LOUD, with doors and windows open, WHILE WEARING HEADPHONES, because he "could feel the bass better that way".

[davef]

Hi,
I'm sitting 12 feet from my L/C/R and 7 feet from the rear. Using ati at527nc to feed my front towers (raal) and Sierra 2 for the back. All tweeter are pointing on the middle seat of a 3 seats couch. Sometimes movies soundtrack sound a little to strident in the mid/high frequency. When is set my Anthem d2v to dolby volume on cinema reference mode, the sound is much more smooth but have the impression that I'm missing the little punch in the chest from sub and lose some particular effects that I have with usually. I believe the receiver clip the dynamic from the soundtrack. I have room acoustics (GIK) on walls and ceiling all around. You have any recommendations for me to get the high level sound (80db reference) without the strident effect? Thanks


Exactly Bruce, - 12 or sometime - 10 is the maximum I can tolerate.

Hi Joblain,

It is important to understand what "reference" volume is, how loud it can be and how much power is required to get there. Reference volume is 85dB average from each speaker measured at the listening position. The peaks for movie soundtracks will be as high as +20dB. Reference volume calls for 105dB peaks from each speaker.

To be able to cleanly play these peaks at your 11 foot listening distance requires 350 watts of power into each speaker. Your amplifier is capable of a max of 200 watts per channel so at the volume levels you are trying to reach, your amp is far exceeding its capability. Your amp uses class D amplification and your description of how the system sounds at these volume levels is precisely what happens to Class D amplification when it "clips", lots of high frequency distortion and compression.

The reason it sound better at these extreme volume levels with Dolby Volume engaged is that Dolby Volume equalizes volume levels and reduces the peaks that are pushing your amp too hard (this is why you are losing some impact as you mentioned)

My recommendation is to either try and rearrange your positioning so that you are sitting closer to the front L/C/R speakers, upgrade to a more powerful amplifier (you will need ~350 watts per channel for the fronts) or save your hearing and stick with slightly lower volume levels. 110dB spl is damaging to human hearing.

Hope this helps!

[joblain]

Have you tried mounting a woofer on your chest? In college, a few of us threatened to do that to an underclassman in our dorm who liked to play his sound system LOUD, with doors and windows open, WHILE WEARING HEADPHONES, because he "could feel the bass better that way".

Wow haha! never thought of that but seems logic, bass frequencies are vibration so you got full range that way!

[joblain]

Hi Joblain,

It is important to understand what "reference" volume is, how loud it can be and how much power is required to get there. Reference volume is 85dB average from each speaker measured at the listening position. The peaks for movie soundtracks will be as high as +20dB. Reference volume calls for 105dB peaks from each speaker.

To be able to cleanly play these peaks at your 11 foot listening distance requires 350 watts of power into each speaker. Your amplifier is capable of a max of 200 watts per channel so at the volume levels you are trying to reach, your amp is far exceeding its capability. Your amp uses class D amplification and your description of how the system sounds at these volume levels is precisely what happens to Class D amplification when it "clips", lots of high frequency distortion and compression.

The reason it sound better at these extreme volume levels with Dolby Volume engaged is that Dolby Volume equalizes volume levels and reduces the peaks that are pushing your amp too hard (this is why you are losing some impact as you mentioned)

My recommendation is to either try and rearrange your positioning so that you are sitting closer to the front L/C/R speakers, upgrade to a more powerful amplifier (you will need ~350 watts per channel for the fronts) or save your hearing and stick with slightly lower volume levels. 110dB spl is damaging to human hearing.

Hope this helps!

Thanks Dave for responding.
Are you sure that my amp can't push enough? Before buying my ati, i Checked over a couple of sites(ex:http://myhometheater.homestead.com/splcalculator.html) to calculate the max SPL I could get and all seem's to indicate with 200watts RMS it's enough. Also, when amp is clipping, it supposed to advertise me with a yellows led light on front but never got that warning.

[racrawford65]

Per ATI, they rate their amps up to clipping, which is 200 wpc in the case of their hypex ncore models.

[davef]

Thanks Dave for responding.
Are you sure that my amp can't push enough? Before buying my ati, i Checked over a couple of sites(ex:http://myhometheater.homestead.com/splcalculator.html) to calculate the max SPL I could get and all seem's to indicate with 200watts RMS it's enough. Also, when amp is clipping, it supposed to advertise me with a yellows led light on front but never got that warning.

Yes I am sure... Remember, Dolby Reference is 105dB peaks from EACH speaker. In that calculator, you must put in 1 speaker and since your room is treated, you must choose "Away" from walls. You will see you are nearly 3dB short, an additional 3dB of output requires double the amplifier power.

I'd also recommend a class A/B amplifier...

[Ascend0577]

Yes I am sure... Remember, Dolby Reference is 105dB peaks from EACH speaker. In that calculator, you must put in 1 speaker and since your room is treated, you must choose "Away" from walls. You will see you are nearly 3dB short, an additional 3dB of output requires double the amplifier power.

I'd also recommend a class A/B amplifier...

Dave,

I have seen in this thread and, at least another, about what seem to be your misgivings about class-D amplification. What do you see as the most notable differences in behavior and/or clipping between class-D and class A/B that would lead to one being less desirable (accurate?) than the other for use with loudspeakers? I think your insights would be very educational.

David

[joblain]

Dave,

I have seen in this thread and, at least another, about what seem to be your misgivings about class-D amplification. What do you see as the most notable differences in behavior and/or clipping between class-D and class A/B that would lead to one being less desirable (accurate?) than the other for use with loudspeakers? I think your insights would be very educational.

David

I believe that if Morris Kessler from ATI stopped the 2000 series and replaced it with the class D then he was confident in the results of the hypex N-Core model or else the other line would have survived.

[davef]

Dave,

I have seen in this thread and, at least another, about what seem to be your misgivings about class-D amplification. What do you see as the most notable differences in behavior and/or clipping between class-D and class A/B that would lead to one being less desirable (accurate?) than the other for use with loudspeakers? I think your insights would be very educational.

David

Class D amplifiers produce switching noise, it is just how they work. Perfectly fine for most loudspeakers out there as most simply can not produce frequencies up that high. However, RAAL ribbons can and do produce these frequencies and even though we can't actually "hear" them, they can lead to fatigue.

https://en.wikipedia.org/wiki/Class-D_amplifier

[davef]

I believe that if Morris Kessler from ATI stopped the 2000 series and replaced it with the class D then he was confident in the results of the hypex N-Core model or else the other line would have survived.

Class D amplifiers offer rather significant manufacturing savings over class A/B by eliminating the challenge and expense of how to dissipate all of that heat. They absolutely have their place in the market and the technology is indeed getting better and better.

[dfurry]

I believe that if Morris Kessler from ATI stopped the 2000 series and replaced it with the class D then he was confident in the results of the hypex N-Core model or else the other line would have survived.

ATI still offers class A/AB amps. Comparing the cost/watt of the ATI 5 channel class A/AB and class D 200W/Channel offerings:

AT4005 ATI Sig 200W x 5 class A/AB amp = $4795 Cost/Watt ~ .48 Cents/Watt
AT525NC ATI N-Core 200W x 5 calls D amp = $2995 Cost/Watt ~ .30 Cents/Watt

While the power output is the same the N-Core has features that the Sig amp does not have and the Sig amp has features that the N-Core does not have but it can't be denied that the AB amp cost more, runs hotter, weighs more, consumes more energy and rack space.

Distortion in the higher frequency ranges introduced by class D amplifier design has been substantially remediated with N-Core design technologies but if the gap were 100% remediated why would anyone buy Class AB with all of the the deficits noted above? We know that the class AB market space is healthy and we see that ATI has some very fine AB offerings to complement their new class D product lines.

ATI's 200W AT2000 AB has been replaced by 200W AT4000 AB & 200W AT52NC Class D
ATI's 300W AT3000 AB has been replaced by 300W AT6000 AB & 500W AT54NC Class D

ATI's class D offerings tell us N-Core improvements made it possible for them to embrace class D for use with primary hifi amplification. ATI's class AB offerings tell us that N-Core is not for everyone.

[Beave]

Class D amplifiers produce switching noise, it is just how they work. Perfectly fine for most loudspeakers out there as most simply can not produce frequencies up that high. However, RAAL ribbons can and do produce these frequencies and even though we can't actually "hear" them, they can lead to fatigue.

https://en.wikipedia.org/wiki/Class-D_amplifier

The evidence that ultrasonics can be sensed ("heard") and can lead to fatigue is tenuous at best. There's that one Japanese study that used MRIs, but I don't think it has been reproduced by anyone else. I would say that ultrasonics "might" lead to some form of listening fatigue or stress, but the evidence that they really do is thin.

I would think a bigger potential issue with class D amps is their higher output impedance, compared to class A/B amps, which can alter a speaker's frequency response. This is becoming less of an issue with modern class D amps.

[davef]

ATI still offers class A/AB amps. Comparing the cost/watt of the ATI 5 channel class A/AB and class D 200W/Channel offerings:

AT4005 ATI Sig 200W x 5 class A/AB amp = $4795 Cost/Watt ~ .48 Cents/Watt
AT525NC ATI N-Core 200W x 5 calls D amp = $2995 Cost/Watt ~ .30 Cents/Watt

While the power output is the same the N-Core has features that the Sig amp does not have and the Sig amp has features that the N-Core does not have but it can't be denied that the AB amp cost more, runs hotter, weighs more, consumes more energy and rack space.

Distortion in the higher frequency ranges introduced by class D amplifier design has been substantially remediated with N-Core design technologies but if the gap were 100% remediated why would anyone buy Class AB with all of the the deficits noted above? We know that the class AB market space is healthy and we see that ATI has some very fine AB offerings to complement their new class D product lines.

ATI's 200W AT2000 AB has been replaced by 200W AT4000 AB & 200W AT52NC Class D
ATI's 300W AT3000 AB has been replaced by 300W AT6000 AB & 500W AT54NC Class D

ATI's class D offerings tell us N-Core improvements made it possible for them to embrace class D for use with primary hifi amplification. ATI's class AB offerings tell us that N-Core is not for everyone.

Excellent post... Also do not forget the ATI 1800 series, with the 5 channel configuration available for $2395 which equates to ~ .37 per watt.

As I have mentioned, I have nothing against Class D (I was promoting and selling B&O's ICEPower before it even hit the mainstream). Just not a fan of Class D in combination with RAAL ribbons, and that is based on feedback from the designer of these ribbons, many hundreds of customers, and personal experience.

I'll share an interesting story... My father suffered from a horrible case of tinnitus. There was one room in the old house I grew up in that aggravated his condition to such a degree, that he couldn't even be in this room for more than 5 minutes. To the rest of my family, we couldn't sense anything and it became a mystery to me. I set out to determine what was the cause of this (his tinnitus acted up even if we had music playing in the room).

For one of my visits, I brought with me some measurement gear capable of reading up to 40kHz. Sure enough, compared to other rooms in the old house, there was quite a bit of noise in the 30kHz region. Our dog Willie also avoided this room... I quickly realized my father wasn't imagining this, it was indeed measurable.

Turned out the culprit was an old CRT TV that while plugged in behind a mess of wires, was never even used. I am not an audiologist, but the one my father was seeing agreed that this was very likely the cause and he had come across issues like these many times - even though on the surface, with hearing loss, it doesn't make much logical sense.

We ended up throwing that old TV out and sure enough, my father had no more issues in this particular room compared to other rooms in the house...

[Ascend0577]

Excellent post... Also do not forget the ATI 1800 series, with the 5 channel configuration available for $2395 which equates to ~ .37 per watt.

As I have mentioned, I have nothing against Class D (I was promoting and selling B&O's ICEPower before it even hit the mainstream). Just not a fan of Class D in combination with RAAL ribbons, and that is based on feedback from the designer of these ribbons, many hundreds of customers, and personal experience.

I'll share an interesting story... My father suffered from a horrible case of tinnitus. There was one room in the old house I grew up in that aggravated his condition to such a degree, that he couldn't even be in this room for more than 5 minutes. To the rest of my family, we couldn't sense anything and it became a mystery to me. I set out to determine what was the cause of this (his tinnitus acted up even if we had music playing in the room).

For one of my visits, I brought with me some measurement gear capable of up reading to 40kHz. Sure enough, compared to other rooms in the old house, there was quite a bit of noise in the 30kHz region. Our dog Willie also avoided this room... I quickly realized my father wasn't imagining this, it was indeed measurable.

Turned out the culprit was an old CRT TV that while plugged in behind a mess of wires, was never even used. I am not an audiologist, but the one my father was seeing agreed that this was very likely the cause and he had come across issues like these many times even though on the surface, with hearing loss, it doesn't make much logical sense.

We ended up throwing that old TV out and sure enough, my father had no more issues in this particular room compared to other rooms in the house...

Thank you, Dave and everyone else! That RAAL ribbons are a specific case due to their ability in the very high frequencies makes more sense to me than a blanket condemnation of class-D, with the generally very high switching frequencies involved.

David

[joblain]

Class D amplifiers offer rather significant manufacturing savings over class A/B by eliminating the challenge and expense of how to dissipate all of that heat. They absolutely have their place in the market and the technology is indeed getting better and better.

Dave, now I know that ribbon and class d is not a good match, i feel sad that i invest almost 3.5k$ in amp that should not go together. Did you have a chance to listen the ribbon with the ati D model? If would like to have your opinion on this. Maybe the hypex ncore500 doesn't have the issue with your speakers, i think they sound pretty well in my room. Strident sound is felt only with very high references volume. I would like to watch movies with same impact than in theater without to drop down volume offently with friends because it's to loud and missing the bass and surround impact.

[davef]

Dave, now I know that ribbon and class d is not a good match, i feel sad that i invest almost 3.5k$ in amp that should not go together. Did you have a chance to listen the ribbon with the ati D model? If would like to have your opinion on this. Maybe the hypex ncore500 doesn't have the issue with your speakers, i think they sound pretty well in my room. Strident sound is felt only with very high references volume. I would like to watch movies with same impact than in theater without to drop down volume offently with friends because it's to loud and missing the bass and surround impact.

Your situation is different, you are trying to achieve reference levels without having enough power to do so. This is why when you are at these volume levels, when you turn on Dolby Volume, it sounds better because Dolby Volume equalizes volume levels and limits the peaks.

Are you using a subwoofer?

[joblain]

Your situation is different, you are trying to achieve reference levels without having enough power to do so. This is why when you are at these volume levels, when you turn on Dolby Volume, it sounds better because Dolby Volume equalizes volume levels and limits the peaks.

Are you using a subwoofer?

An svs pb 13 ultra. Looking for a second one, same model or a rythmik like you advised.

[davef]

An svs pb 13 ultra. Looking for a second one, same model or a rythmik like you advised.

A second sub will definitely provide performance improvements in the area of impact. What crossover frequency are you using?

[joblain]

A second sub will definitely provide performance improvements in the area of impact. What crossover frequency are you using?

60hz with the tower, 65 hz with the Sierra 2 rears.

[davef]

60hz with the tower, 65 hz with the Sierra 2 rears.

At the volume levels you are trying to achieve, I would recommend crossing over both the towers and S2's at 80Hz. This will free up some additional dynamic power in your amp...