Oh Krell, my Krell

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Originally Posted by JohnMichael

... One day I need to listen to another Class D amp to see if what troubles me about the Onkyo is typical with Class D designs. I have even been thinking about a budget integrated amp as a back up for the Krell and selling the Onkyo. ...

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What qualifies as 'budget', JM?

The Peachtree nova65SE looks kind of interesting to me, and it's presently only $800. It's a class D with tube buffered input; it has a built in Sabre DAC but no phono. See HERE.

http://www.peachtreeaudio.com/media/...e-rw-angle.jpg

Teac has some nice integrated amps like this one for $699

AX-501 | TEAC

Dagogo has given some of their gear nice reviews.

I was just trying to listen to the Onkyo for a few hours of music when it became fatiguing. I certainly do not want another Class D amp. I just need to be patient for the Krell.

I hope all goes well with your Krell.It depends which class D amplifier you listen to.I think the sound I get from my custom class A amplifier and from my Pioneer SC-LX87 av receiver (class d power amp section) is superior to ANY class AB amplifier. I can't stand the crossover distortion of class AB amplifiers.

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Originally Posted by Kursun

I hope all goes well with your Krell.It depends which class D amplifier you listen to.I think the sound I get from my custom class A amplifier and from my Pioneer SC-LX87 av receiver (class d power amp section) is superior to ANY class AB amplifier. I can't stand the crossover distortion of class AB amplifiers.

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I haven't noticed any distortion. Maybe that's because I keep mine in class A.

No distortion with my Pass either. Never heard it with my Parasound A21 either.

Some of the worst amps that I heard were NCores. A friend brought his NC monoblocks over to my house and we compared them to my Pass. He bought a new amp that week.

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Originally Posted by Kursun

I hope all goes well with your Krell.It depends which class D amplifier you listen to.I think the sound I get from my custom class A amplifier and from my Pioneer SC-LX87 av receiver (class d power amp section) is superior to ANY class AB amplifier. I can't stand the crossover distortion of class AB amplifiers.

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I am surprised that the switching distortion of Class D does not bother you if Class A/B crossover distortion does.

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Originally Posted by JohnMichael

I am surprised that the switching distortion of Class D does not bother you if Class A/B crossover distortion does.

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Switching occurs at ultrasonic frequencies at which even my dog can't hear. Class AB amplifiers distort the wave at every frequency within human hearing range.Pass Labs amps of course are class A.

My Pass is Class A up to about 20wpc, maybe more, maybe less depending upon what you read. The Parasound was Class A up to 8-10wpc. Maybe my hearing is not good enough to hear it.

20W per channel is probably all you need most of the time.My thesis is that class D amplifiers have matured now and a properly designed and built class D amplifier is superior to class AB designs.

Just because something is happening in the frequencies above human hearing does not mean it does not interfere with the music.

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Originally Posted by JohnMichael

Just because something is happening in the frequencies above human hearing does not mean it does not interfere with the music.

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Theoretically you may be correct.But my judgement is based on what I hear, not theories.

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Originally Posted by Kursun

20W per channel is probably all you need most of the time.My thesis is that class D amplifiers have matured now and a properly designed and built class D amplifier is superior to class AB designs.

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No, I don't acceot the global assertion that class D amps are now superior to class AB amps.

There are two things I do believe however: (1) class D amps don't all sound the same, and (2) some class D amp sound better than some class AB amps.

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Originally Posted by Kursun

20W per channel is probably all you need most of the time.My thesis is that class D amplifiers have matured now and a properly designed and built class D amplifier is superior to class AB designs.

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If you can get one of the major audio publications ( Stereophile or The Absolute Sound for example) to agree with you, then your theory might hold water. It doesn't sound like those of us with AB amps who have previously owned class D agree.

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Originally Posted by Jack in Wilmington

If you can get one of the major audio publications ( Stereophile or The Absolute Sound for example) to agree with you, then your theory might hold water. It doesn't sound like those of us with AB amps who have previously owned class D agree.

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““…previously” might be the key Word here. Class D has evolved. Once it was only good for subwoofers. I am not a circuit design guru but higher switching frequencies may have helped a lot.______“A lot of times, people don't know what they want until you show it to them.” – Steve Jobs______A lot of people aren’t aware of the virtues of class A. But they do have their drawbacks. People believe class D is just not good enough…So manufacturers shovel class AB through consumers’ throats. Because it is practical to design and sell class AB.I had been blessed/cursed with a pair of Yamaha NS1000M speakers. Like my AKG K701 headphones they let you hear tiniest amount of defect in the source. For me they are the best speakers in the world regardless of price. For those of you not familiar with these speakers here is a short glimpse: Yamaha NS-1000M | I have used several class AB amplifiers to drive the Yamaha NS1000Ms with disastrous results. Midrange and highs were much too bright and hard, too little bass. I decided to build a solid state class A power amplifier to drive it. Postimage.org / Pure Class A Power Amplifier II Result was unbelievable. Midrange and highs are now transparent as pure water and bass is deep with great authority (although power is only a 2x30W./that'a 500W torodidal power transformer inside).Later when it was time to replace my AV receiver I looked at the top of the line Pioneer receivers, I was disappointed to see that all of their higher models were class D. I didn’t think fondly of class D at the time. Well I bought Pioneer SC-LX87 anyway. When I hooked it up, WOW! Its sound is almost close to the class A power amplifier! Class A amplifier on steroids!The truth is Class AB is practical for the industry to build and the consumer to buy. Both the industry and the consumer is happy. I don’t know why Stereophile or other publications investigate the matter. Though they do their listening evaluation I think one problem lies with the labs measuring THD and IM while the amplifier is connected to purely resistive 8 ohm dummy loads. The general public starts to think their amplifier is totally distortion free, while class B/AB crossover distortion grind their ears.

Sorry,I don't know why my paragraphs are garbled.

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Originally Posted by Kursun

““…previously” might be the key Word here. Class D has evolved. Once it was only good for subwoofers. I am not a circuit design guru but higher switching frequencies may have helped a lot.______“A lot of times, people don't know what they want until you show it to them.” – Steve Jobs______A lot of people aren’t aware of the virtues of class A. But they do have their drawbacks. People believe class D is just not good enough…So manufacturers shovel class AB through consumers’ throats. Because it is practical to design and sell class AB.I had been blessed/cursed with a pair of Yamaha NS1000M speakers. Like my AKG K701 headphones they let you hear tiniest amount of defect in the source. For me they are the best speakers in the world regardless of price. For those of you not familiar with these speakers here is a short glimpse: Yamaha NS-1000M | I have used several class AB amplifiers to drive the Yamaha NS1000Ms with disastrous results. Midrange and highs were much too bright and hard, too little bass. I decided to build a solid state class A power amplifier to drive it. Postimage.org / Pure Class A Power Amplifier II Result was unbelievable. Midrange and highs are now transparent as pure water and bass is deep with great authority (although power is only a 2x30W./that'a 500W torodidal power transformer inside).Later when it was time to replace my AV receiver I looked at the top of the line Pioneer receivers, I was disappointed to see that all of their higher models were class D. I didn’t think fondly of class D at the time. Well I bought Pioneer SC-LX87 anyway. When I hooked it up, WOW! Its sound is almost close to the class A power amplifier! Class A amplifier on steroids!The truth is Class AB is practical for the industry to build and the consumer to buy. Both the industry and the consumer is happy. I don’t know why Stereophile or other publications investigate the matter. Though they do their listening evaluation I think one problem lies with the labs measuring THD and IM while the amplifier is connected to purely resistive 8 ohm dummy loads. The general public starts to think their amplifier is totally distortion free, while class B/AB crossover distortion grind their ears.

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I just know that I've had 2 class D amps in my system, a tube amp and a solid state and neither could drive my speakers like my Pass Labs amp can drive them. The class D's just seem to fall apart when the music got complex and didn't take the highs to their apex and instead rolled them off. If you're right I'd expect to see some class D amps rated in the Class "A" or even "B" when Stereophile does their annual best of the best article. I'll look for that this year when the article hits the news stand. I'll also read closely the articles on class D amps and see if they mention being better now than class AB.

If you have a Pass Labs amplifier, anything by Nelson Pass, I frankly think you don't need to look any further.

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Originally Posted by Kursun

If you have a Pass Labs amplifier, anything by Nelson Pass, I frankly think you don't need to look any further.

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I agree, I didn't feel like I had to, but then you got me thinking that maybe I missed something in my two class D amps. Maybe with a speaker that is an easier load like an 8 ohm 90 sensitivity speaker.

Class D is popular now, almost every large manufacturer has something Class D to offer and several Class D only brands like Red Dragon, NuForce, Channel Island etc. I just had in my system a great set of Class D monoblocks from Merrill Audio. In evaluating it is good to have another good amp to compare with like the Pass. In short, the Veritas were smooth, clear, detailed, quick and powerful. In comparing the two brands there were some trades. I didn't notice this before but have been told Class D lacks in dynamics. It took me a while to notice this in the Veritas due to the fast transients but on a particular song it became apparent. The song starts soft then swells with intensity on the Pass, the same song on the Veritas the music didn't swell. Once I became aware of the difference I could hear it in voices and other areas. Despite this nature in the Veritas they were still musical and had good timing.

In the end I still preferred my Pass for what I already mentioned plus I enjoy the warmer midrange and fuller bass.

It's to the point now that you can't stereotype Class D any more and that's a good thing. The Veritas has pristine tones on things like bells, cymbals etc. that were not fatiguing at all. It will really depend on what one likes to listen to and you are going for. If you wanted max detail from a recording the Veritas would be hard to beat. They also had good bass it was super controlled.

I just checked emails and a notice from UPS states that my Krell will be home tomorrow. Tonight I am working my seventh night in a row but I think I will have the energy to put it back in the system. I do not know what they repaired until I read the packing slip. Sounds like no sleep tomorrow. Thanks Krell!

JM will be a happy camper :)

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Originally Posted by Mr Peabody

Class D is popular now, almost every large manufacturer has something Class D to offer and several Class D only brands like Red Dragon, NuForce, Channel Island etc. I just had in my system a great set of Class D monoblocks from Merrill Audio. In evaluating it is good to have another good amp to compare with like the Pass. In short, the Veritas were smooth, clear, detailed, quick and powerful. In comparing the two brands there were some trades. I didn't notice this before but have been told Class D lacks in dynamics. It took me a while to notice this in the Veritas due to the fast transients but on a particular song it became apparent. The song starts soft then swells with intensity on the Pass, the same song on the Veritas the music didn't swell. Once I became aware of the difference I could hear it in voices and other areas. Despite this nature in the Veritas they were still musical and had good timing.

In the end I still preferred my Pass for what I already mentioned plus I enjoy the warmer midrange and fuller bass.

It's to the point now that you can't stereotype Class D any more and that's a good thing. The Veritas has pristine tones on things like bells, cymbals etc. that were not fatiguing at all. It will really depend on what one likes to listen to and you are going for. If you wanted max detail from a recording the Veritas would be hard to beat. They also had good bass it was super controlled.

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Ha! Remarkable: this is pretty close to how I would describe the difference between my Pass Labs X150.5 and my Class D Audio SDS-258. I would only add that the Pass has not exactly more detail, but more palpable 3D imaging and soundstage depth.

One difference between the CLD SDS-258 and the Merrill Veritas though: the former cost $650 while the latter cost $12,000.

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Originally Posted by Feanor

Ha! Remarkable: this is pretty close to how I would describe the difference between my Pass Labs X150.5 and my Class D Audio SDS-258. I would only add that the Pass has not exactly more detail, but more palpable 3D imaging and soundstage depth.

One difference between the CLD SDS-258 and the Merrill Veritas though: the former cost $650 while the latter cost $12,000.

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The Merrill had more detail in laying bare what was in the track, it was musical, I just find Pass a very satisfying balance of all aspects to my taste.

I auditioned the Class D amp Harley had, not sure where your amp is in the line compared to his. The Class D doesn't compare to the Merrill, whether it's worth the many times more in price only the listener could say. Merrill has taken best of show at a couple of the audio shows.

I'm curious what these Red Dragon amps sound like, made in the U.S. and also reasonably priced.

My Krell is home and sounding good. So much more instrumental texture than with the Onkyo. Cheers to a long life.