Does class D have the Heft of SS

[Munjibunga]

Well I know it's different to a standard class d and it uses a toroidal transformer. And it was designed to be superior to the class d amps out at the time.
It's not just class d renamed so I don't think you understand it actually

You're punching above your weight here.

 

[cfsporn]

Aguilar said in other stuff that it did and together with the class t part made the amp better than the class d amps of the time.

It's Aguilar's job to say it does. That sort of stuff sells amps.

 

[cfsporn]

I can build an amplifier with a toroidal transformer based power supply using this ICEPower 500A (same design as in all the 500 watt Class D amps only lacking the integrated SMPS of the 500ASP module that is actually in those heads).

It wouldn't sound as good as Mr. @agedhorse's Genz Benzes.

 

[BadExample]

I was just playin

Sez the dressed up pug

 

[Brad Johnson]

I see his signiture but does that mean he knows everything. And if he does then why not teach me rather than just saying there isn't any.
I'm not trying to school anyone. I would love to learn more about the differences.
As said from reading there does seem to be differences in the designs. Again Aguilar from reading there literature pointed this out.

Did it ever dawn on you that if he's telling you there aren't fundamental differences he is teaching you?


I typically learn more when I listen. You do not appear to be doing that. I remember reading about class T and what has been mentioned does indeed sound familiar. Why you feel it has to mean something more is a mystery. What is that feeling based on? Hopefully not old data or marketing. What is that something more that you think must be there?

If you do want to bother with some basic research make sure you look at the dates of the info. I just saw on an AVS forum back in 2004 that class T is class D and then someone responded that they must be different because while class T was used for full spectrum amps, class D was only used for subwoofers. Context matters.


So feel free to expound on your knowledge of the subject, challenging him with what you don't appear to know or take advantage of the opportunity to speak directly to a longtime industry expert. The choice is obviously yours.

 

[agedhorse]

May I ask in the case of that amp (ag500) the transformer they used makes a difference to a class d or in this case named class t performance.
My original post in regard to the ag500 using a conventional power supply was to ask if it did make a difference. Aguilar said in other stuff that it did and together with the class t part made the amp better than the class d amps of the time.

Now this is a good question IMO, and one that deserves an "it depends" answer...

IMO, and I am answering this in general terms since this is not an amplifier that I can comment on specifically, my experience in developing amplifiers has shown that it is entirely possible to create an SMPS that has (virtually) the same V/I load curves (meaning that the different supply's output impedances track closely) as a line frequency supply. In this case it was impossible for any of the players conducting listening tests to hear any difference between the two otherwise identical amplifiers. The specific product that this test was carried out with was the NeoPak 3.5, ultimately we decided the SMPS was the best of all worlds and went with that in production.

It all comes down to the design goals of the product and the skill of the designer in achieving the target goals. Some designers are more comfortable with line frequency power supplies, some with SMPS, and with some designers it doesn't matter since they can do both. The same applies to power amplifier topologies.

 

[2manynotes]

Can anyone define "heft" and explain what sense of heft can't be manipulated by eq?

"Heft" is what your wallet has before you buy a 500W Class D amp.

 

[bass151]

What cfsporn said. Wouldn't sound as good as a ----------------

 

[MrCash]

It's Aguilar's job to say it does. That sort of stuff sells amps.

Indeed. But a few people have mentioned or should I say have the theory that part of why some class d amps lack heft compared to older designs is because of the power supply.
My question in mentioning class t was about the Aguilar ag500 design. Which used the toroidal transformer etc. And did it have a benefit? To class d or whatever amps. Did the power supply make a difference.

Then the conversation got skewed slightly as others thought I meant something else.

I'm just trying to learn and ask questions.

 

[MrCash]

You're punching above your weight here.

Once again I need to explain my meaning was taken wrong at the original question. If I knew that I could have explained what I meant and wanted to know better.

 

[Munjibunga]

Once again I need to explain my meaning was taken wrong at the original question. If I knew that I could have explained what I meant and wanted to know better.

Ok then.

 

[bass151]

So $400 to $600 is a lot for 500 watts?

 

[okcrum]

From Aguilar's blurb.
The conventional class AB power amplifier is a tried-and-true design, but one that operates relatively inefficiently, producing enough excess heat to require noisy fans and large heat sinks, which add to an amplifier’s bulk. Class D amps are far more efficient. They produce power by switching transistors on and off at a high frequency using a process called Pulse Width Modulation. The AG 500 is like a Class D amp, but it utilizes switching technology developed by the Tripath Corporation. The Tripath power amp topology, named Class T, modulates the output using a proprietary module that purports to eliminate some of the weaknesses of Class D amps while maintaining the efficiency that’s a hallmark of the technology. Aguilar’s AG 500 uses a Class T output stage and a conventional linear power transformer.

What's different is Tripath took the class D driver circuitry, added a few things (variable switching frequency and the feedback design being the most notable), put it all on one chip, and patented it. Then they called the whole amp class T because of the chip design. These days, every good class D driver does the same things and more than Tripath's chip does. It's the tail end of the technology curve that Tripath is milking.

The state of the art has advanced a fair distance since Tripath developed that chip 20 years ago.

 

[Brad Johnson]

Indeed. But a few people have mentioned or should I say have the theory that part of why some class d amps lack heft compared to older designs is because of the power supply.
My question in mentioning class t was about the Aguilar ag500 design. Which used the toroidal transformer etc. And did it have a benefit? To class d or whatever amps. Did the power supply make a difference.

Then the conversation got skewed slightly as others thought I meant something else.

I'm just trying to learn and ask questions.

Aguilar no longer offers it. There might be an answer in there.

 

[BadExample]

"Heft" is what your wallet has before you buy a 500W Class D amp.

Not so much. Compare the $/watt to anything else. I got mine at about $0.38/watt. If I could get a home stereo amp at that price and quality, I'd be all over a huge amp. Besides, digital money we use weighs about nothing It's all in the physics of an electron.

 

[Brad Johnson]

So $400 to $600 is a lot for 500 watts?

Nowadays? Actually yeah. You can get 1,000w @ 4 ohms for that price.

 

[MrCash]

Now this is a good question IMO, and one that deserves an "it depends" answer...

IMO, and I am answering this in general terms since this is not an amplifier that I can comment on specifically, my experience in developing amplifiers has shown that it is entirely possible to create an SMPS that has (virtually) the same V/I load curves (meaning that the different supply's output impedances track closely) as a line frequency supply. In this case it was impossible for any of the players conducting listening tests to hear any difference between the two otherwise identical amplifiers. The specific product that this test was carried out with was the NeoPak 3.5, ultimately we decided the SMPS was the best of all worlds and went with that in production.

It all comes down to the design goals of the product and the skill of the designer in achieving the target goals. Some designers are more comfortable with line frequency power supplies, some with SMPS, and with some designers it doesn't matter since they can do both. The same applies to power amplifier topologies.

I think I understand you. And thank you for the reply.

Would the tests have shown a difference if conducted not with people but various electronic instruments. I don't know the technical term but as well as the various equipment that records noise levels and frequency, adding and I know this might sound a bit out the box here but an instrument that measures floor or room vibration?
Could it be that's where the differences (heft) that people claim to feel from class d to traditional amp design are not in volume etc but in simple terms vibration, energy in the room?

 

[BadExample]

Nowadays? Actually yeah. You can get 1,000w @ 4 ohms for that price.

$600 will get you 1600 watts into 2 ohms of US made class D. And a Helluvalota features, including a 12ax7 pre and all sorts of tone control.

 

[Handyman]

What's different is Tripath took the class D driver circuitry, added a few things (variable switching frequency and the feedback design being the most notable), put it all on one chip, and patented it. Then they called the whole amp class T because of the chip design. These days, every good class D driver does the same things and more than Tripath's chip does. It's the tail end of the technology curve that Tripath is milking.

The state of the art has advanced a fair distance past Tripath since they developed that chip 20 years ago.

To be fair, Tripath hasn't existed for about 9 years. Its Cirrus Logic, who bought the rights to the Tripath designs after Tripath itself went bankrupt, that's miking the old designs.

Its totally not shocking that outfits like B&O who keep investing in pushing the state of the art manage to do better than a 10+ year old design.

 

[Brad Johnson]