Class A/B vs Class D amp comparisons

[RichB]

The Stereophile review of the No53 was interesting. I can't stand Michael Fremer, but JA's measurements and listening tests were an enigma, to use his word.

Mark Levinson No.53 Reference monoblock power amplifier | Stereophile.com

Interesting read.
I see what you mean:

I took a listen to the Mark Levinsons driving Wilson Alexandria XLF speakers in his listening room. (Not only did I want to hear for myself if Michael was correct in his description of the No.53's character; as a longtime owner of a pair of the older Mark Levinson No.33H monoblocks, I was interested in hearing how the new amplifiers sounded.) The sound was initially very impressive. It had tremendous dynamic sweep, with superb control of the Wilsons' woofers, tremendous clarity, and nothing identifiably wrong. However, the more I listened, the more the overall sonic picture seemed flat and uninvolving. An enigma.—John Atkinson

That seals the deal. I am definitely not buying a pair of these amps

- Rich

 

[panteragstk]

I would highly recommend an SMSL. Even though you're buying direct from the Asians and therefore support will take a little longer and be a bit less convenient, I would argue that you're getting a lot more amp for your money compared to others sold by PE and the like.

I've got my eye on this one. Pretty decent wattage. I'll use it for something.

 

[fuzz092888]

I've got my eye on this one. Pretty decent wattage. I'll use it for something.

That's the newer version of the one I have. I'm using it for my computer monitors right now and the volume knob is about a quarter turn up, plus I usually only have the computer volume up 2-6 ticks, so it's got plenty of power. With the knob at a 1/4 turn it easily fills my living room with the Mandolins, I think you'll be pretty happy with it if you get it.

 

[macddmac]

All of this discussion makes the delivery of this later this week all the more exciting

 

[fuzz092888]

Looks awesome Makes me that much more determined to try and close my own deal

All of this discussion makes the delivery of this later this week all the more exciting

 

[panteragstk]

That's the newer version of the one I have. I'm using it for my computer monitors right now and the volume knob is about a quarter turn up, plus I usually only have the computer volume up 2-6 ticks, so it's got plenty of power. With the knob at a 1/4 turn it easily fills my living room with the Mandolins, I think you'll be pretty happy with it if you get it.

Awesome. Can't wait.

 

[macddmac]

Looks awesome Makes me that much more determined to try and close my own deal

Thanks, Nao I need to get my deserving speaker project going.. Thinking Tempestas
Cheers, Mac

 

[fuzz092888]

Thanks, Nao I need to get my deserving speaker project going.. Thinking Tempestas
Cheers, Mac

I'm actually mulling over the matching center for Tempestas as a build. Suddenly I find myself in need of a center..........

 

[macddmac]

I'm actually mulling over the matching center for Tempestas as a build. Suddenly I find myself in need of a center..........

Sounds like a magnifico idea

 

[RichB]

All of this discussion makes the delivery of this later this week all the more exciting

Great amp.
Please post your impressions.

- Rich

 

[PENG]

Great amp.
Please post your impressions.

- Rich

If you can't wait for him, check your PM, more to come...

 

[RichB]

If you can't wait for him, check your PM, more to come...

Great. I responded.
Feel free to jump in here. The water is great

- Rich

 

[PENG]

Great. I responded.
Feel free to jump in here. The water is great

- Rich

Thanks for that thoughtful and detailed response. I took a couple of days off for this but has to go out for a while now. Just a quick response to your question, my mains are KEF R900, Veritas 2.3i and Focal 1028 Be. This new toy is hooked up to the R900 to AB with the SM-7. The SM-6 is class A,A/B selectable by a selector switch. I cannot confirm if the SM-7 is A/AB as it does not have that selector so it would have to be done with automatic bias control. It sure runs hot though even idling.

 

[Ampdog]

As to why manufacturers have not largely switched to class D, I cannot help thinking that economy has a lot to do with it. Right - I may be contradicting myself - on the whole it should be rather cheaper to produce class D amps than class AB (analogue). But I would believe firms factor in converting to a new design as well as public opinion (as to the latter: and how!) into - again - profitability.

I am not a businessman and cannot analyse the above accurately, just seems to be an important factor in what should possibly be seen as an over-stocked market. (I doubt that a firm would engage in audio amplifier production to become affluent.)

Perhaps on the technical side, if someone could come up with arguments as to whether/why the one class should be inherently superior to the other? (economical factors excluded)

 

[fuzz092888]

Well look at Rotel. They had a huge following with their class A/B HT amps and switched to class D amps. Deserved or not, they got slammed and promptly switched back to their tried and true class A/B design, all in less than 2 years IIRC. That should tell you something about the market and mentality of the buyers.

As to why manufacturers have not largely switched to class D, I cannot help thinking that economy has a lot to do with it. Right - I may be contradicting myself - on the whole it should be rather cheaper to produce class D amps than class AB (analogue). But I would believe firms factor in converting to a new design as well as public opinion (as to the latter: and how!) into - again - profitability.

I am not a businessman and cannot analyse the above accurately, just seems to be an important factor in what should possibly be seen as an over-stocked market. (I doubt that a firm would engage in audio amplifier production to become affluent.)

Perhaps on the technical side, if someone could come up with arguments as to whether/why the one class should be inherently superior to the other? (economical factors excluded)

 

[AcuDefTechGuy]

I think the key is always price. No way people will switch unless given a significant incentive - if the the price is significantly less than the other A/B amps.

If Rotel had made a class-D 200WPC x 5Ch amp for $1,000, hells yeah I think people would buy that instead of the $900 EMO XPA-5.

 

[fuzz092888]

I think the key is always price. No way people will switch unless given a significant incentive - if the the price is significantly less than the other A/B amps.

If Rotel had made a class-D 200WPC x 5Ch amp for $1,000, hells yeah I think people would buy that instead of the $900 EMO XPA-5.

I understand why they wouldn't though. If they had priced the 1575 at $1000, when the 1095 was priced at $2800, then they would get hit with the quality questions, why is it so much cheaper, it probably isn't as good and on and on. What they needed to do, if they were to go that route (IMHO) is create a 200X5 for $1000, and then a 400X5 for $2800. Market the 200WPC unit as a HT amp and the more expensive model as the Reference HT amp.

 

[AcuDefTechGuy]

I understand why they wouldn't though. If they had priced the 1575 at $1000, when the 1095 was priced at $2800, then they would get hit with the quality questions, why is it so much cheaper, it probably isn't as good and on and on. What they needed to do, if they were to go that route (IMHO) is create a 200X5 for $1000, and then a 400X5 for $2800. Market the 200WPC unit as a HT amp and the more expensive model as the Reference HT amp.

Once everyone gets those amps at the lower price, then they could insidiously jack up the prices.

But most people are just not going to switch from A/B to D without an amazing reason. And the reason is always price.

The only reason people buy Emotiva is because they are cheaper than everyone else. Sure, they are good. But if Emotiva cost the same as everyone else, no one would buy Emotiva IMO.

 

[fuzz092888]

Well, price, weight, efficiency and therefore the dedicated circuits that would or wouldn't be needed could also be factors. Having an amp that can push 200WPC X 5 (1000W total) and only need to draw 1100 watts from the wall, is a pretty big deal when a class A/B would need to draw at least 1500W and require a bump up from a 15 amp dedicated to a 20 amp dedicated to get full power.

Once everyone gets those amps at the lower price, then they could insidiously jack up the prices.

But most people are just not going to switch from A/B to D without an amazing reason. And the reason is always price.

The only reason people buy Emotiva is because they are cheaper than everyone else. Sure, they are good. But if Emotiva cost the same as everyone else, no one would buy Emotiva IMO.

 

[RichB]

Once everyone gets those amps at the lower price, then they could insidiously jack up the prices.

But most people are just not going to switch from A/B to D without an amazing reason. And the reason is always price.

The only reason people buy Emotiva is because they are cheaper than everyone else. Sure, they are good. But if Emotiva cost the same as everyone else, no one would buy Emotiva IMO.

I think we will have that tested soon. Emotiva had a price increase on the XPR-5.
It was on sale for around $1,800 (not sure though). The new price is 2,069.00.

It boasts more power than some of the Alternatives from Outlaw and ATI but not a lot more.
It is possible that some do not buy products for high-end systems when they are perceived as too inexpensive to be good.

- Rich