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Do you see Class D being the standard in AVRs to come?

Plcamp

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I suspect that the inherent advantages of higher power density per unit weight, size and efficiency will result in class d dominance.

Perhaps it could follow a similar path of development to that of power converter bricks, which standardized package sizes, footprints and thermal interfaces. Cost per watt would lower considerably I would expect.

Edit…this half inch high by about 2.5” square converter delivers 600W. Kinda shows what might be possible.
 
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Roland68

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I have touched on the difference between the different power classes of ARs and AVRs, understood that Class D seems to be the way to go, for every one, power cost, heat and ultimatley the enviroment. This also seems to be one of my key things in my upcoming AVR purchase since the place it will be in, is not super ventilated. My question to my fellow members here in ASR: Do you think Class D will be more implemented in low and mid tier of AVRs and upper AVRs ? Looking at the IT-sector the rules of how a power supply and its efficency as well as usage has become more strict (Lot9), in Europe. I read some of the pinned post in this section of the forum (....FTC), but was not sure if its the exact same as I am asking for.

Can we see this coming, what do you think?
For the upper/top class, the question comes too late. Pioneer had already installed 82 Ice Power Modules in its two top devices Pioneer SC-LX90 and SC-LX 82 in 2009. Both devices got the best test reports.
But Ice Power Modules are expensive for the manufacturers and other Class D solutions either have to be developed in-house or bought in. So it also depends on costs, benefits, effort (development) and marketing when Class D arrives in all A/V receivers. But in the long run it will arrive everywhere.
Especially in Europe, however, the legislators will also have more and more influence on electricity consumption.
 

JeffS7444

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Interesting, can you please elaborate?
The Tripath TA2022 was what I'd consider a "difficult" amplifier IC, in the sense that, even if you followed manufacturer's guidelines, it could cause audible interference with nearby AM radios, and best I could manage was to reduce the most obvious of it's radio interference to a radius of ~ 1 meter. I can't imagine that it would be easy for products containing a TA2022 to qualify for FCC Class B certification! Too bad, because at the time, Tripath's amplifier ICs were well regarded for their "musicality", and TA2022 was their highest powered offering. So far as I can see, newer IC designs by the likes of Texas Instruments have largely solved the EMI problem, but remember that an AVR could need 11 of the things.

OTOH, since Class AB amplifiers are only operating at audio frequencies, there's far less potential for them to act as radio transmitters.
 
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abdo123

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Price per watt

Really? This is quite shocking cause i always thought that was the greatest hindrance. For someone like Denon that can whip out a class AB amplifier for peanuts because there are no royalties or licensed chips involved i always thought it is cheaper for them not to go class D.
 

wwenze

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In the past we have non-oversampling DACs. Then 1-bit DACs came. Then multibit oversampling DACs became the standard.

Just a matter of time before amps do the same. Rail-switching class D would be analogous to multibit. Charge pumps can be a good voltage adder too.
 

rdenney

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Really? This is quite shocking cause i always thought that was the greatest hindrance. For someone like Denon that can whip out a class AB amplifier for peanuts because there are no royalties or licensed chips involved i always thought it is cheaper for them not to go class D.
Price per watt might come into play if they considered distribution costs as well as production costs, especially given high transport fuel costs. AB amps are heavy and bulky.

But I'll bet most of the cost of an AVR is in the software (including licensing), all those myriad of physical connections, and the pretty case. The amps are just a stock design thrown in. I'll bet the costs for the typical consumer AVR are ten bucks or less per channel for the amplifier. Even the lower-line Hypex UCD amps are much more than that. I suspect that at lower price points, chip amps are the future.

For higher-end AVRs, their price points might justify more care in the selection of the amp.

We are used to excellent Class D amps being cheaper than excellent AB amps because we are buying Class D amps from specialist producers with build-to-order absence of carried inventory, low margins, and a very sparse distribution network. There's no way Dylan's Buckeye amps, for example, could sell at his price points if the exact same product was produced by, say, Denon, who would be expected to float a vast inventory through a range of distribution middlemen covering, say, every Best Buy in the country. I would expect them to cost three times as much, at least.

Rick "software obsolescence begs for separate amps and connection panels instead of integrated AVRs, however, even at low price points" Denney
 
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DrStranger

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No the lower end Chassis 505 and Down are Class AB - the TOTL chassis currently still 704 and 904 are Class D.

They were supposed to release the updated TOTL models (705 / 905) early this year, but it seems like it won't happen till late this year - and by the time the AVR's hit retail it will be 2023
There is so much "lag' with many electronics due to supply issue, I wonder if they will make it. I mentioned before in anoyher thread that I fear that many electronic device manufactors, that are not developing "important" products might solve their planned release with less quality components in order to get something out and not loosing money. I hope your dates are good, I am AVR thirsty, I need my fix...
 

mhardy6647

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The ability for AVR manufacturers to just buy someone else's amplifier solution and drop it into their products, coupled with some perceived superiority of Class D (efficiency) will, I would think, make them ubiquitous very soon.
 
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DrStranger

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The Tripath TA2022 was what I'd consider a "difficult" amplifier IC, in the sense that, even if you followed manufacturer's guidelines, it could cause audible interference with nearby AM radios, and best I could manage was to reduce the most obvious of it's radio interference to a radius of ~ 1 meter. I can't imagine that it would be easy for products containing a TA2022 to qualify for FCC Class B certification! Too bad, because at the time, Tripath's amplifier ICs were well regarded for their "musicality", and TA2022 was their highest powered offering. So far as I can see, newer IC designs by the likes of Texas Instruments have largely solved the EMI problem, but remember that an AVR could need 11 of the things.

OTOH, since Class AB amplifiers are only operating at audio frequencies, there's far less potential for them to act as radio transmitters.
Do you think this would be the case in these "modern times" for Class D? I mean the way things are beeing developed, 'kaizen' seems to be something that many industrys towards. Sure, the HIFI industry is not taking that much room in the tech and power hungry indutry as IT: Server, Networking and Storage , they eat alot and therefor chasing power and cooling cost reduction on a daily basis.
 

AdamG

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Really? This is quite shocking cause i always thought that was the greatest hindrance. For someone like Denon that can whip out a class AB amplifier for peanuts because there are no royalties or licensed chips involved i always thought it is cheaper for them not to go class D.
As @rdenney has elaborated. I was thinking about the whole manufacture to storefront costs per watt of power. But I don’t argue against your point either. It was just a guess anyway as I am simply a spectator and not involved in this business. Drawing upon my purchase experience with big heavy AVR’S with relatively low wattage power per channel when compared to something like the Hypex Ncore Nc502mp amp module. However, jamming 6 or 7 of these into a single case is going to be large and heavy I suspect. But just think of the performance differences here. 500 WPC @4ohms verses what Denon offers in their Flagship 13 channel amp AVR-8500h at 190 WPC @6ohms. Only rates this AVR for @4ohms with 2 channels. This AVR brand new was $5k. Buckeye is offering a 8ch 502 for $2300 delivered. So price parity just looking at WPC favors the class D. Of course the AVR does much more than just being an amplifier. Therefore your argument is valid and until a commercial product of equivalent performance and capability is brought to market this is just a guessing game. I’m talking Denon/Marantz level market here not the High end stuff as that is mostly cost prohibitive for the majority of consumers.
 

Shiva

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I used to have a couple of the Panasonic digital receivers back when they became popular, including their final offering, the Panasonic SA-BX500. My Old Man is still rocking the Pioneer Elite SC-05, with the Class D amps. Bought new and still going strong. That is fairly impressive longevity for a receiver.
 

Roland68

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As @rdenney has elaborated. I was thinking about the whole manufacture to storefront costs per watt of power. But I don’t argue against your point either. It was just a guess anyway as I am simply a spectator and not involved in this business. Drawing upon my purchase experience with big heavy AVR’S with relatively low wattage power per channel when compared to something like the Hypex Ncore Nc502mp amp module. However, jamming 6 or 7 of these into a single case is going to be large and heavy I suspect. But just think of the performance differences here. 500 WPC @4ohms verses what Denon offers in their Flagship 13 channel amp AVR-8500h at 190 WPC @6ohms. Only rates this AVR for @4ohms with 2 channels. This AVR brand new was $5k. Buckeye is offering a 8ch 502 for $2300 delivered. So price parity just looking at WPC favors the class D. Of course the AVR does much more than just being an amplifier. Therefore your argument is valid and until a commercial product of equivalent performance and capability is brought to market this is just a guessing game. I’m talking Denon/Marantz level market here not the High end stuff as that is mostly cost prohibitive for the majority of consumers.
It becomes even clearer in the low-cost or DIY sector.
Order 4 x stereo amplifiers with TPA3255, e.g. the Aiyima A07 and matching Meanwell power supplies. They stay under €/$ 500 and have real 8 x 250 watts into 4 ohms or 8 x 180 watts into 8 ohms, not just 2 x.

You can do the same as a DIY with ready-made DIY boards with TPA3255. 4 x stereo 35 each, plus 600 watts of industrial SMPS and a housing, also stays under €/$ 500.

Or you can get together with 2-3 other users and order 1 box of Ice Power modules with 200, 300 or 400 watts and a housing, complete with small parts, for approx. €/$ 900 - 1100.
Very clean structure with 8 x 200, 300 or 400 watts. It is up to you how many channels you need or how much power (there are also 700 and 1200 watt modules), but each mono module delivers full power, not just for 2 channels.
 

voodooless

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It becomes even clearer in the low-cost or DIY sector.
Order 4 x stereo amplifiers with TPA3255, e.g. the Aiyima A07 and matching Meanwell power supplies. They stay under €/$ 500 and have real 8 x 250 watts into 4 ohms or 8 x 180 watts into 8 ohms, not just 2 x.

You can do the same as a DIY with ready-made DIY boards with TPA3255. 4 x stereo 35 each, plus 600 watts of industrial SMPS and a housing, also stays under €/$ 500.

Or you can get together with 2-3 other users and order 1 box of Ice Power modules with 200, 300 or 400 watts and a housing, complete with small parts, for approx. €/$ 900 - 1100.
Very clean structure with 8 x 200, 300 or 400 watts. It is up to you how many channels you need or how much power (there are also 700 and 1200 watt modules), but each mono module delivers full power, not just for 2 channels.
Don’t forget that these prices are not realistic for a retail AVR. A markup of 3x to 5x must be accounted for before it’s in the store. Even if they buy in bulk, that’s still a significant difference. Your $500 amps are then $1500 to $ 2000…

Even the X8500h uses what looks to be a super cheap single layer PCB with through hole components:
1660070064082.jpeg


Why? Because it works, has been used for many years and is cheap-as-F == more profit!
 
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DrStranger

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Don’t forget that these prices are not realistic for a retail AVR. A markup of 3x to 5x must be accounted for before it’s in the store. Even if they buy in bulk, that’s still a significant difference. Your $500 amps are then $1500 to $ 2000…

Even the X8500h uses what looks to be a super cheap single layer PCB with through hole components:
View attachment 223310

Why? Because it works, has been used for many years and is cheap-as-F == more profit!
One would think a pricey AVR like that would look more fancy that this.... :)
 

Roland68

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This. I would buy a 5 channel Buckeye Amp tomorrow if there was a reasonably priced processor I could pair it with for processing and reliable HDMI switching.
Be careful with your desires
You could take a Canton Smart Connect 5.1 V2, or a used Yamaha RX-V 779 / 781 or RX-A 850 / 860 / 870 / 880, all with preamp outputs and 4K HDMI.
But of course there is something like that from the other manufacturers.

I myself use the RX-V 779 as a processor (ok, it can push 2 effect loudspeakers) and operate it with 2 x Aiyima A07 and 2 x Ice Power. Real 1550 watts without a subwoofer for less than 800,-, including the used Yamaha RX-V 779.
Even at room volume, the difference to the internal amplifier is huge.
 

dlaloum

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As a horn guy, I appreciate the lack of crossover distortion with class D. A CD and horn are about 20dB more sensitive than a cone driver, and correspondingly more sensitive to that sort of thing. Of course us hornies are 0.000001% of the market. Other than that, the best AB amps still have substantial bias current and heat. And require a substantial heat sink for continuous high power operation.
You would have thought so, but my older Onkyo 876 achieved 140W@8ohm for all channels without the power amps warming up - what got hot was the Video & DSP circuits! - The computing parts...

My current Integra DRX 3.4 - also Class AB - the power amp section seems cool at all times (well sometimes slightly warm) - but the HDMI board, clearly gets much warmer (I hesitate to call it HOT - the old models, you could fry an egg on, that is no longer the case).

My Quad 606 140W power amps also only ever get warm to the touch - Class AB need not be very hot to sound decent.
 

DMill

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Yes. Brands will make the change when they have to. Until then they will ride out old tech until it’s irrelevant. Smart companies will be proactive. IMHO
 

JeffS7444

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Do you think this would be the case in these "modern times" for Class D? I mean the way things are beeing developed, 'kaizen' seems to be something that many industrys towards.
Yes of course these problems have been solved in newer products, but whether Class D amplification vs Class AB sells many AVRs is another matter!
 
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